| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Dave Airlie | 10827 | 40.71% | 17 | 6.83% |
| Stephen Chandler Paul | 9495 | 35.70% | 61 | 24.50% |
| Sean Paul | 1152 | 4.33% | 7 | 2.81% |
| Ville Syrjälä | 854 | 3.21% | 12 | 4.82% |
| Imre Deak | 745 | 2.80% | 30 | 12.05% |
| Wayne Lin | 569 | 2.14% | 16 | 6.43% |
| Sam McNally | 492 | 1.85% | 1 | 0.40% |
| David Francis | 468 | 1.76% | 4 | 1.61% |
| Mikita Lipski | 446 | 1.68% | 5 | 2.01% |
| Dhinakaran Pandiyan | 438 | 1.65% | 6 | 2.41% |
| Jani Nikula | 136 | 0.51% | 6 | 2.41% |
| Benjamin Gaignard | 134 | 0.50% | 2 | 0.80% |
| Mykola Lysenko | 107 | 0.40% | 5 | 2.01% |
| Jim Bride | 99 | 0.37% | 1 | 0.40% |
| Eryk Brol | 88 | 0.33% | 1 | 0.40% |
| Hersen Wu | 58 | 0.22% | 2 | 0.80% |
| Bhawanpreet Lakha | 45 | 0.17% | 2 | 0.80% |
| Thierry Reding | 42 | 0.16% | 2 | 0.80% |
| Libin Yang | 39 | 0.15% | 1 | 0.40% |
| Daniel Vetter | 36 | 0.14% | 9 | 3.61% |
| Nikola Cornij | 29 | 0.11% | 2 | 0.80% |
| Chris Wilson | 22 | 0.08% | 4 | 1.61% |
| Ben Skeggs | 21 | 0.08% | 7 | 2.81% |
| Joe Perches | 21 | 0.08% | 1 | 0.40% |
| Harry Wentland | 18 | 0.07% | 3 | 1.20% |
| Hamza Mahfooz | 18 | 0.07% | 1 | 0.40% |
| Rickard Strandqvist | 18 | 0.07% | 1 | 0.40% |
| Pankaj Bharadiya | 17 | 0.06% | 2 | 0.80% |
| Maarten Lankhorst | 15 | 0.06% | 1 | 0.40% |
| Ramalingam C | 14 | 0.05% | 1 | 0.40% |
| José Roberto de Souza | 13 | 0.05% | 4 | 1.61% |
| Colin Ian King | 12 | 0.05% | 1 | 0.40% |
| Dingchen Zhang | 9 | 0.03% | 1 | 0.40% |
| Shawn C Lee | 9 | 0.03% | 1 | 0.40% |
| Lukasz Majczak | 8 | 0.03% | 1 | 0.40% |
| Anshuman Gupta | 8 | 0.03% | 1 | 0.40% |
| Andrey Grodzovsky | 8 | 0.03% | 1 | 0.40% |
| Andy Shevchenko | 7 | 0.03% | 1 | 0.40% |
| Simon Ser | 6 | 0.02% | 1 | 0.40% |
| Joe Moriarty | 5 | 0.02% | 1 | 0.40% |
| Hangyu Hua | 5 | 0.02% | 1 | 0.40% |
| Matt Roper | 4 | 0.02% | 1 | 0.40% |
| Thomas Zimmermann | 4 | 0.02% | 3 | 1.20% |
| Rajkumar Subbiah | 4 | 0.02% | 1 | 0.40% |
| Damien Lespiau | 4 | 0.02% | 1 | 0.40% |
| Jesse Barnes | 4 | 0.02% | 2 | 0.80% |
| Rob Clark | 3 | 0.01% | 1 | 0.40% |
| Vlastimil Babka | 3 | 0.01% | 1 | 0.40% |
| Hans Verkuil | 3 | 0.01% | 1 | 0.40% |
| Wambui Karuga | 2 | 0.01% | 2 | 0.80% |
| Baoyou Xie | 1 | 0.00% | 1 | 0.40% |
| Azeem Shaikh | 1 | 0.00% | 1 | 0.40% |
| Maya Rashish | 1 | 0.00% | 1 | 0.40% |
| Bagas Sanjaya | 1 | 0.00% | 1 | 0.40% |
| Alex Deucher | 1 | 0.00% | 1 | 0.40% |
| Khan, Imran | 1 | 0.00% | 1 | 0.40% |
| Manasi D Navare | 1 | 0.00% | 1 | 0.40% |
| Chenwandun | 1 | 0.00% | 1 | 0.40% |
| Francisco Jerez | 1 | 0.00% | 1 | 0.40% |
| Total | 26593 | 249 |
/* * Copyright © 2014 Red Hat * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that * the above copyright notice appear in all copies and that both that copyright * notice and this permission notice appear in supporting documentation, and * that the name of the copyright holders not be used in advertising or * publicity pertaining to distribution of the software without specific, * written prior permission. The copyright holders make no representations * about the suitability of this software for any purpose. It is provided "as * is" without express or implied warranty. * * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE * OF THIS SOFTWARE. */ #include <linux/bitfield.h> #include <linux/delay.h> #include <linux/errno.h> #include <linux/i2c.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/random.h> #include <linux/sched.h> #include <linux/seq_file.h> #include <linux/iopoll.h> #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) #include <linux/stacktrace.h> #include <linux/sort.h> #include <linux/timekeeping.h> #include <linux/math64.h> #endif #include <drm/display/drm_dp_mst_helper.h> #include <drm/drm_atomic.h> #include <drm/drm_atomic_helper.h> #include <drm/drm_drv.h> #include <drm/drm_edid.h> #include <drm/drm_fixed.h> #include <drm/drm_print.h> #include <drm/drm_probe_helper.h> #include "drm_dp_helper_internal.h" #include "drm_dp_mst_topology_internal.h" /** * DOC: dp mst helper * * These functions contain parts of the DisplayPort 1.2a MultiStream Transport * protocol. The helpers contain a topology manager and bandwidth manager. * The helpers encapsulate the sending and received of sideband msgs. */ struct drm_dp_pending_up_req { struct drm_dp_sideband_msg_hdr hdr; struct drm_dp_sideband_msg_req_body msg; struct list_head next; }; static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, char *buf); static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port); static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, int id, u8 start_slot, u8 num_slots); static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int offset, int size, u8 *bytes); static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int offset, int size, u8 *bytes); static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb); static void drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb); static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *port); static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, u8 *guid); static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port); static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port); static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr); static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, struct drm_dp_mst_branch *branch); #define DBG_PREFIX "[dp_mst]" #define DP_STR(x) [DP_ ## x] = #x static const char *drm_dp_mst_req_type_str(u8 req_type) { static const char * const req_type_str[] = { DP_STR(GET_MSG_TRANSACTION_VERSION), DP_STR(LINK_ADDRESS), DP_STR(CONNECTION_STATUS_NOTIFY), DP_STR(ENUM_PATH_RESOURCES), DP_STR(ALLOCATE_PAYLOAD), DP_STR(QUERY_PAYLOAD), DP_STR(RESOURCE_STATUS_NOTIFY), DP_STR(CLEAR_PAYLOAD_ID_TABLE), DP_STR(REMOTE_DPCD_READ), DP_STR(REMOTE_DPCD_WRITE), DP_STR(REMOTE_I2C_READ), DP_STR(REMOTE_I2C_WRITE), DP_STR(POWER_UP_PHY), DP_STR(POWER_DOWN_PHY), DP_STR(SINK_EVENT_NOTIFY), DP_STR(QUERY_STREAM_ENC_STATUS), }; if (req_type >= ARRAY_SIZE(req_type_str) || !req_type_str[req_type]) return "unknown"; return req_type_str[req_type]; } #undef DP_STR #define DP_STR(x) [DP_NAK_ ## x] = #x static const char *drm_dp_mst_nak_reason_str(u8 nak_reason) { static const char * const nak_reason_str[] = { DP_STR(WRITE_FAILURE), DP_STR(INVALID_READ), DP_STR(CRC_FAILURE), DP_STR(BAD_PARAM), DP_STR(DEFER), DP_STR(LINK_FAILURE), DP_STR(NO_RESOURCES), DP_STR(DPCD_FAIL), DP_STR(I2C_NAK), DP_STR(ALLOCATE_FAIL), }; if (nak_reason >= ARRAY_SIZE(nak_reason_str) || !nak_reason_str[nak_reason]) return "unknown"; return nak_reason_str[nak_reason]; } #undef DP_STR #define DP_STR(x) [DRM_DP_SIDEBAND_TX_ ## x] = #x static const char *drm_dp_mst_sideband_tx_state_str(int state) { static const char * const sideband_reason_str[] = { DP_STR(QUEUED), DP_STR(START_SEND), DP_STR(SENT), DP_STR(RX), DP_STR(TIMEOUT), }; if (state >= ARRAY_SIZE(sideband_reason_str) || !sideband_reason_str[state]) return "unknown"; return sideband_reason_str[state]; } static int drm_dp_mst_rad_to_str(const u8 rad[8], u8 lct, char *out, size_t len) { int i; u8 unpacked_rad[16]; for (i = 0; i < lct; i++) { if (i % 2) unpacked_rad[i] = rad[i / 2] >> 4; else unpacked_rad[i] = rad[i / 2] & BIT_MASK(4); } /* TODO: Eventually add something to printk so we can format the rad * like this: 1.2.3 */ return snprintf(out, len, "%*phC", lct, unpacked_rad); } /* sideband msg handling */ static u8 drm_dp_msg_header_crc4(const uint8_t *data, size_t num_nibbles) { u8 bitmask = 0x80; u8 bitshift = 7; u8 array_index = 0; int number_of_bits = num_nibbles * 4; u8 remainder = 0; while (number_of_bits != 0) { number_of_bits--; remainder <<= 1; remainder |= (data[array_index] & bitmask) >> bitshift; bitmask >>= 1; bitshift--; if (bitmask == 0) { bitmask = 0x80; bitshift = 7; array_index++; } if ((remainder & 0x10) == 0x10) remainder ^= 0x13; } number_of_bits = 4; while (number_of_bits != 0) { number_of_bits--; remainder <<= 1; if ((remainder & 0x10) != 0) remainder ^= 0x13; } return remainder; } static u8 drm_dp_msg_data_crc4(const uint8_t *data, u8 number_of_bytes) { u8 bitmask = 0x80; u8 bitshift = 7; u8 array_index = 0; int number_of_bits = number_of_bytes * 8; u16 remainder = 0; while (number_of_bits != 0) { number_of_bits--; remainder <<= 1; remainder |= (data[array_index] & bitmask) >> bitshift; bitmask >>= 1; bitshift--; if (bitmask == 0) { bitmask = 0x80; bitshift = 7; array_index++; } if ((remainder & 0x100) == 0x100) remainder ^= 0xd5; } number_of_bits = 8; while (number_of_bits != 0) { number_of_bits--; remainder <<= 1; if ((remainder & 0x100) != 0) remainder ^= 0xd5; } return remainder & 0xff; } static inline u8 drm_dp_calc_sb_hdr_size(struct drm_dp_sideband_msg_hdr *hdr) { u8 size = 3; size += (hdr->lct / 2); return size; } static void drm_dp_encode_sideband_msg_hdr(struct drm_dp_sideband_msg_hdr *hdr, u8 *buf, int *len) { int idx = 0; int i; u8 crc4; buf[idx++] = ((hdr->lct & 0xf) << 4) | (hdr->lcr & 0xf); for (i = 0; i < (hdr->lct / 2); i++) buf[idx++] = hdr->rad[i]; buf[idx++] = (hdr->broadcast << 7) | (hdr->path_msg << 6) | (hdr->msg_len & 0x3f); buf[idx++] = (hdr->somt << 7) | (hdr->eomt << 6) | (hdr->seqno << 4); crc4 = drm_dp_msg_header_crc4(buf, (idx * 2) - 1); buf[idx - 1] |= (crc4 & 0xf); *len = idx; } static bool drm_dp_decode_sideband_msg_hdr(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_hdr *hdr, u8 *buf, int buflen, u8 *hdrlen) { u8 crc4; u8 len; int i; u8 idx; if (buf[0] == 0) return false; len = 3; len += ((buf[0] & 0xf0) >> 4) / 2; if (len > buflen) return false; crc4 = drm_dp_msg_header_crc4(buf, (len * 2) - 1); if ((crc4 & 0xf) != (buf[len - 1] & 0xf)) { drm_dbg_kms(mgr->dev, "crc4 mismatch 0x%x 0x%x\n", crc4, buf[len - 1]); return false; } hdr->lct = (buf[0] & 0xf0) >> 4; hdr->lcr = (buf[0] & 0xf); idx = 1; for (i = 0; i < (hdr->lct / 2); i++) hdr->rad[i] = buf[idx++]; hdr->broadcast = (buf[idx] >> 7) & 0x1; hdr->path_msg = (buf[idx] >> 6) & 0x1; hdr->msg_len = buf[idx] & 0x3f; idx++; hdr->somt = (buf[idx] >> 7) & 0x1; hdr->eomt = (buf[idx] >> 6) & 0x1; hdr->seqno = (buf[idx] >> 4) & 0x1; idx++; *hdrlen = idx; return true; } void drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req, struct drm_dp_sideband_msg_tx *raw) { int idx = 0; int i; u8 *buf = raw->msg; buf[idx++] = req->req_type & 0x7f; switch (req->req_type) { case DP_ENUM_PATH_RESOURCES: case DP_POWER_DOWN_PHY: case DP_POWER_UP_PHY: buf[idx] = (req->u.port_num.port_number & 0xf) << 4; idx++; break; case DP_ALLOCATE_PAYLOAD: buf[idx] = (req->u.allocate_payload.port_number & 0xf) << 4 | (req->u.allocate_payload.number_sdp_streams & 0xf); idx++; buf[idx] = (req->u.allocate_payload.vcpi & 0x7f); idx++; buf[idx] = (req->u.allocate_payload.pbn >> 8); idx++; buf[idx] = (req->u.allocate_payload.pbn & 0xff); idx++; for (i = 0; i < req->u.allocate_payload.number_sdp_streams / 2; i++) { buf[idx] = ((req->u.allocate_payload.sdp_stream_sink[i * 2] & 0xf) << 4) | (req->u.allocate_payload.sdp_stream_sink[i * 2 + 1] & 0xf); idx++; } if (req->u.allocate_payload.number_sdp_streams & 1) { i = req->u.allocate_payload.number_sdp_streams - 1; buf[idx] = (req->u.allocate_payload.sdp_stream_sink[i] & 0xf) << 4; idx++; } break; case DP_QUERY_PAYLOAD: buf[idx] = (req->u.query_payload.port_number & 0xf) << 4; idx++; buf[idx] = (req->u.query_payload.vcpi & 0x7f); idx++; break; case DP_REMOTE_DPCD_READ: buf[idx] = (req->u.dpcd_read.port_number & 0xf) << 4; buf[idx] |= ((req->u.dpcd_read.dpcd_address & 0xf0000) >> 16) & 0xf; idx++; buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff00) >> 8; idx++; buf[idx] = (req->u.dpcd_read.dpcd_address & 0xff); idx++; buf[idx] = (req->u.dpcd_read.num_bytes); idx++; break; case DP_REMOTE_DPCD_WRITE: buf[idx] = (req->u.dpcd_write.port_number & 0xf) << 4; buf[idx] |= ((req->u.dpcd_write.dpcd_address & 0xf0000) >> 16) & 0xf; idx++; buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff00) >> 8; idx++; buf[idx] = (req->u.dpcd_write.dpcd_address & 0xff); idx++; buf[idx] = (req->u.dpcd_write.num_bytes); idx++; memcpy(&buf[idx], req->u.dpcd_write.bytes, req->u.dpcd_write.num_bytes); idx += req->u.dpcd_write.num_bytes; break; case DP_REMOTE_I2C_READ: buf[idx] = (req->u.i2c_read.port_number & 0xf) << 4; buf[idx] |= (req->u.i2c_read.num_transactions & 0x3); idx++; for (i = 0; i < (req->u.i2c_read.num_transactions & 0x3); i++) { buf[idx] = req->u.i2c_read.transactions[i].i2c_dev_id & 0x7f; idx++; buf[idx] = req->u.i2c_read.transactions[i].num_bytes; idx++; memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); idx += req->u.i2c_read.transactions[i].num_bytes; buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 4; buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); idx++; } buf[idx] = (req->u.i2c_read.read_i2c_device_id) & 0x7f; idx++; buf[idx] = (req->u.i2c_read.num_bytes_read); idx++; break; case DP_REMOTE_I2C_WRITE: buf[idx] = (req->u.i2c_write.port_number & 0xf) << 4; idx++; buf[idx] = (req->u.i2c_write.write_i2c_device_id) & 0x7f; idx++; buf[idx] = (req->u.i2c_write.num_bytes); idx++; memcpy(&buf[idx], req->u.i2c_write.bytes, req->u.i2c_write.num_bytes); idx += req->u.i2c_write.num_bytes; break; case DP_QUERY_STREAM_ENC_STATUS: { const struct drm_dp_query_stream_enc_status *msg; msg = &req->u.enc_status; buf[idx] = msg->stream_id; idx++; memcpy(&buf[idx], msg->client_id, sizeof(msg->client_id)); idx += sizeof(msg->client_id); buf[idx] = 0; buf[idx] |= FIELD_PREP(GENMASK(1, 0), msg->stream_event); buf[idx] |= msg->valid_stream_event ? BIT(2) : 0; buf[idx] |= FIELD_PREP(GENMASK(4, 3), msg->stream_behavior); buf[idx] |= msg->valid_stream_behavior ? BIT(5) : 0; idx++; } break; } raw->cur_len = idx; } EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_encode_sideband_req); /* Decode a sideband request we've encoded, mainly used for debugging */ int drm_dp_decode_sideband_req(const struct drm_dp_sideband_msg_tx *raw, struct drm_dp_sideband_msg_req_body *req) { const u8 *buf = raw->msg; int i, idx = 0; req->req_type = buf[idx++] & 0x7f; switch (req->req_type) { case DP_ENUM_PATH_RESOURCES: case DP_POWER_DOWN_PHY: case DP_POWER_UP_PHY: req->u.port_num.port_number = (buf[idx] >> 4) & 0xf; break; case DP_ALLOCATE_PAYLOAD: { struct drm_dp_allocate_payload *a = &req->u.allocate_payload; a->number_sdp_streams = buf[idx] & 0xf; a->port_number = (buf[idx] >> 4) & 0xf; WARN_ON(buf[++idx] & 0x80); a->vcpi = buf[idx] & 0x7f; a->pbn = buf[++idx] << 8; a->pbn |= buf[++idx]; idx++; for (i = 0; i < a->number_sdp_streams; i++) { a->sdp_stream_sink[i] = (buf[idx + (i / 2)] >> ((i % 2) ? 0 : 4)) & 0xf; } } break; case DP_QUERY_PAYLOAD: req->u.query_payload.port_number = (buf[idx] >> 4) & 0xf; WARN_ON(buf[++idx] & 0x80); req->u.query_payload.vcpi = buf[idx] & 0x7f; break; case DP_REMOTE_DPCD_READ: { struct drm_dp_remote_dpcd_read *r = &req->u.dpcd_read; r->port_number = (buf[idx] >> 4) & 0xf; r->dpcd_address = (buf[idx] << 16) & 0xf0000; r->dpcd_address |= (buf[++idx] << 8) & 0xff00; r->dpcd_address |= buf[++idx] & 0xff; r->num_bytes = buf[++idx]; } break; case DP_REMOTE_DPCD_WRITE: { struct drm_dp_remote_dpcd_write *w = &req->u.dpcd_write; w->port_number = (buf[idx] >> 4) & 0xf; w->dpcd_address = (buf[idx] << 16) & 0xf0000; w->dpcd_address |= (buf[++idx] << 8) & 0xff00; w->dpcd_address |= buf[++idx] & 0xff; w->num_bytes = buf[++idx]; w->bytes = kmemdup(&buf[++idx], w->num_bytes, GFP_KERNEL); if (!w->bytes) return -ENOMEM; } break; case DP_REMOTE_I2C_READ: { struct drm_dp_remote_i2c_read *r = &req->u.i2c_read; struct drm_dp_remote_i2c_read_tx *tx; bool failed = false; r->num_transactions = buf[idx] & 0x3; r->port_number = (buf[idx] >> 4) & 0xf; for (i = 0; i < r->num_transactions; i++) { tx = &r->transactions[i]; tx->i2c_dev_id = buf[++idx] & 0x7f; tx->num_bytes = buf[++idx]; tx->bytes = kmemdup(&buf[++idx], tx->num_bytes, GFP_KERNEL); if (!tx->bytes) { failed = true; break; } idx += tx->num_bytes; tx->no_stop_bit = (buf[idx] >> 5) & 0x1; tx->i2c_transaction_delay = buf[idx] & 0xf; } if (failed) { for (i = 0; i < r->num_transactions; i++) { tx = &r->transactions[i]; kfree(tx->bytes); } return -ENOMEM; } r->read_i2c_device_id = buf[++idx] & 0x7f; r->num_bytes_read = buf[++idx]; } break; case DP_REMOTE_I2C_WRITE: { struct drm_dp_remote_i2c_write *w = &req->u.i2c_write; w->port_number = (buf[idx] >> 4) & 0xf; w->write_i2c_device_id = buf[++idx] & 0x7f; w->num_bytes = buf[++idx]; w->bytes = kmemdup(&buf[++idx], w->num_bytes, GFP_KERNEL); if (!w->bytes) return -ENOMEM; } break; case DP_QUERY_STREAM_ENC_STATUS: req->u.enc_status.stream_id = buf[idx++]; for (i = 0; i < sizeof(req->u.enc_status.client_id); i++) req->u.enc_status.client_id[i] = buf[idx++]; req->u.enc_status.stream_event = FIELD_GET(GENMASK(1, 0), buf[idx]); req->u.enc_status.valid_stream_event = FIELD_GET(BIT(2), buf[idx]); req->u.enc_status.stream_behavior = FIELD_GET(GENMASK(4, 3), buf[idx]); req->u.enc_status.valid_stream_behavior = FIELD_GET(BIT(5), buf[idx]); break; } return 0; } EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_decode_sideband_req); void drm_dp_dump_sideband_msg_req_body(const struct drm_dp_sideband_msg_req_body *req, int indent, struct drm_printer *printer) { int i; #define P(f, ...) drm_printf_indent(printer, indent, f, ##__VA_ARGS__) if (req->req_type == DP_LINK_ADDRESS) { /* No contents to print */ P("type=%s\n", drm_dp_mst_req_type_str(req->req_type)); return; } P("type=%s contents:\n", drm_dp_mst_req_type_str(req->req_type)); indent++; switch (req->req_type) { case DP_ENUM_PATH_RESOURCES: case DP_POWER_DOWN_PHY: case DP_POWER_UP_PHY: P("port=%d\n", req->u.port_num.port_number); break; case DP_ALLOCATE_PAYLOAD: P("port=%d vcpi=%d pbn=%d sdp_streams=%d %*ph\n", req->u.allocate_payload.port_number, req->u.allocate_payload.vcpi, req->u.allocate_payload.pbn, req->u.allocate_payload.number_sdp_streams, req->u.allocate_payload.number_sdp_streams, req->u.allocate_payload.sdp_stream_sink); break; case DP_QUERY_PAYLOAD: P("port=%d vcpi=%d\n", req->u.query_payload.port_number, req->u.query_payload.vcpi); break; case DP_REMOTE_DPCD_READ: P("port=%d dpcd_addr=%05x len=%d\n", req->u.dpcd_read.port_number, req->u.dpcd_read.dpcd_address, req->u.dpcd_read.num_bytes); break; case DP_REMOTE_DPCD_WRITE: P("port=%d addr=%05x len=%d: %*ph\n", req->u.dpcd_write.port_number, req->u.dpcd_write.dpcd_address, req->u.dpcd_write.num_bytes, req->u.dpcd_write.num_bytes, req->u.dpcd_write.bytes); break; case DP_REMOTE_I2C_READ: P("port=%d num_tx=%d id=%d size=%d:\n", req->u.i2c_read.port_number, req->u.i2c_read.num_transactions, req->u.i2c_read.read_i2c_device_id, req->u.i2c_read.num_bytes_read); indent++; for (i = 0; i < req->u.i2c_read.num_transactions; i++) { const struct drm_dp_remote_i2c_read_tx *rtx = &req->u.i2c_read.transactions[i]; P("%d: id=%03d size=%03d no_stop_bit=%d tx_delay=%03d: %*ph\n", i, rtx->i2c_dev_id, rtx->num_bytes, rtx->no_stop_bit, rtx->i2c_transaction_delay, rtx->num_bytes, rtx->bytes); } break; case DP_REMOTE_I2C_WRITE: P("port=%d id=%d size=%d: %*ph\n", req->u.i2c_write.port_number, req->u.i2c_write.write_i2c_device_id, req->u.i2c_write.num_bytes, req->u.i2c_write.num_bytes, req->u.i2c_write.bytes); break; case DP_QUERY_STREAM_ENC_STATUS: P("stream_id=%u client_id=%*ph stream_event=%x " "valid_event=%d stream_behavior=%x valid_behavior=%d", req->u.enc_status.stream_id, (int)ARRAY_SIZE(req->u.enc_status.client_id), req->u.enc_status.client_id, req->u.enc_status.stream_event, req->u.enc_status.valid_stream_event, req->u.enc_status.stream_behavior, req->u.enc_status.valid_stream_behavior); break; default: P("???\n"); break; } #undef P } EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_dp_dump_sideband_msg_req_body); static inline void drm_dp_mst_dump_sideband_msg_tx(struct drm_printer *p, const struct drm_dp_sideband_msg_tx *txmsg) { struct drm_dp_sideband_msg_req_body req; char buf[64]; int ret; int i; drm_dp_mst_rad_to_str(txmsg->dst->rad, txmsg->dst->lct, buf, sizeof(buf)); drm_printf(p, "txmsg cur_offset=%x cur_len=%x seqno=%x state=%s path_msg=%d dst=%s\n", txmsg->cur_offset, txmsg->cur_len, txmsg->seqno, drm_dp_mst_sideband_tx_state_str(txmsg->state), txmsg->path_msg, buf); ret = drm_dp_decode_sideband_req(txmsg, &req); if (ret) { drm_printf(p, "<failed to decode sideband req: %d>\n", ret); return; } drm_dp_dump_sideband_msg_req_body(&req, 1, p); switch (req.req_type) { case DP_REMOTE_DPCD_WRITE: kfree(req.u.dpcd_write.bytes); break; case DP_REMOTE_I2C_READ: for (i = 0; i < req.u.i2c_read.num_transactions; i++) kfree(req.u.i2c_read.transactions[i].bytes); break; case DP_REMOTE_I2C_WRITE: kfree(req.u.i2c_write.bytes); break; } } static void drm_dp_crc_sideband_chunk_req(u8 *msg, u8 len) { u8 crc4; crc4 = drm_dp_msg_data_crc4(msg, len); msg[len] = crc4; } static void drm_dp_encode_sideband_reply(struct drm_dp_sideband_msg_reply_body *rep, struct drm_dp_sideband_msg_tx *raw) { int idx = 0; u8 *buf = raw->msg; buf[idx++] = (rep->reply_type & 0x1) << 7 | (rep->req_type & 0x7f); raw->cur_len = idx; } static int drm_dp_sideband_msg_set_header(struct drm_dp_sideband_msg_rx *msg, struct drm_dp_sideband_msg_hdr *hdr, u8 hdrlen) { /* * ignore out-of-order messages or messages that are part of a * failed transaction */ if (!hdr->somt && !msg->have_somt) return false; /* get length contained in this portion */ msg->curchunk_idx = 0; msg->curchunk_len = hdr->msg_len; msg->curchunk_hdrlen = hdrlen; /* we have already gotten an somt - don't bother parsing */ if (hdr->somt && msg->have_somt) return false; if (hdr->somt) { memcpy(&msg->initial_hdr, hdr, sizeof(struct drm_dp_sideband_msg_hdr)); msg->have_somt = true; } if (hdr->eomt) msg->have_eomt = true; return true; } /* this adds a chunk of msg to the builder to get the final msg */ static bool drm_dp_sideband_append_payload(struct drm_dp_sideband_msg_rx *msg, u8 *replybuf, u8 replybuflen) { u8 crc4; memcpy(&msg->chunk[msg->curchunk_idx], replybuf, replybuflen); msg->curchunk_idx += replybuflen; if (msg->curchunk_idx >= msg->curchunk_len) { /* do CRC */ crc4 = drm_dp_msg_data_crc4(msg->chunk, msg->curchunk_len - 1); if (crc4 != msg->chunk[msg->curchunk_len - 1]) print_hex_dump(KERN_DEBUG, "wrong crc", DUMP_PREFIX_NONE, 16, 1, msg->chunk, msg->curchunk_len, false); /* copy chunk into bigger msg */ memcpy(&msg->msg[msg->curlen], msg->chunk, msg->curchunk_len - 1); msg->curlen += msg->curchunk_len - 1; } return true; } static bool drm_dp_sideband_parse_link_address(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; int i; memcpy(repmsg->u.link_addr.guid, &raw->msg[idx], 16); idx += 16; repmsg->u.link_addr.nports = raw->msg[idx] & 0xf; idx++; if (idx > raw->curlen) goto fail_len; for (i = 0; i < repmsg->u.link_addr.nports; i++) { if (raw->msg[idx] & 0x80) repmsg->u.link_addr.ports[i].input_port = 1; repmsg->u.link_addr.ports[i].peer_device_type = (raw->msg[idx] >> 4) & 0x7; repmsg->u.link_addr.ports[i].port_number = (raw->msg[idx] & 0xf); idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.link_addr.ports[i].mcs = (raw->msg[idx] >> 7) & 0x1; repmsg->u.link_addr.ports[i].ddps = (raw->msg[idx] >> 6) & 0x1; if (repmsg->u.link_addr.ports[i].input_port == 0) repmsg->u.link_addr.ports[i].legacy_device_plug_status = (raw->msg[idx] >> 5) & 0x1; idx++; if (idx > raw->curlen) goto fail_len; if (repmsg->u.link_addr.ports[i].input_port == 0) { repmsg->u.link_addr.ports[i].dpcd_revision = (raw->msg[idx]); idx++; if (idx > raw->curlen) goto fail_len; memcpy(repmsg->u.link_addr.ports[i].peer_guid, &raw->msg[idx], 16); idx += 16; if (idx > raw->curlen) goto fail_len; repmsg->u.link_addr.ports[i].num_sdp_streams = (raw->msg[idx] >> 4) & 0xf; repmsg->u.link_addr.ports[i].num_sdp_stream_sinks = (raw->msg[idx] & 0xf); idx++; } if (idx > raw->curlen) goto fail_len; } return true; fail_len: DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_remote_dpcd_read(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.remote_dpcd_read_ack.port_number = raw->msg[idx] & 0xf; idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.remote_dpcd_read_ack.num_bytes = raw->msg[idx]; idx++; if (idx > raw->curlen) goto fail_len; memcpy(repmsg->u.remote_dpcd_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_dpcd_read_ack.num_bytes); return true; fail_len: DRM_DEBUG_KMS("link address reply parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_remote_dpcd_write(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.remote_dpcd_write_ack.port_number = raw->msg[idx] & 0xf; idx++; if (idx > raw->curlen) goto fail_len; return true; fail_len: DRM_DEBUG_KMS("parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_remote_i2c_read_ack(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.remote_i2c_read_ack.port_number = (raw->msg[idx] & 0xf); idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.remote_i2c_read_ack.num_bytes = raw->msg[idx]; idx++; /* TODO check */ memcpy(repmsg->u.remote_i2c_read_ack.bytes, &raw->msg[idx], repmsg->u.remote_i2c_read_ack.num_bytes); return true; fail_len: DRM_DEBUG_KMS("remote i2c reply parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_enum_path_resources_ack(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.path_resources.port_number = (raw->msg[idx] >> 4) & 0xf; repmsg->u.path_resources.fec_capable = raw->msg[idx] & 0x1; idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.path_resources.full_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); idx += 2; if (idx > raw->curlen) goto fail_len; repmsg->u.path_resources.avail_payload_bw_number = (raw->msg[idx] << 8) | (raw->msg[idx+1]); idx += 2; if (idx > raw->curlen) goto fail_len; return true; fail_len: DRM_DEBUG_KMS("enum resource parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_allocate_payload_ack(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.allocate_payload.port_number = (raw->msg[idx] >> 4) & 0xf; idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.allocate_payload.vcpi = raw->msg[idx]; idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.allocate_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx+1]); idx += 2; if (idx > raw->curlen) goto fail_len; return true; fail_len: DRM_DEBUG_KMS("allocate payload parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_query_payload_ack(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.query_payload.port_number = (raw->msg[idx] >> 4) & 0xf; idx++; if (idx > raw->curlen) goto fail_len; repmsg->u.query_payload.allocated_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); idx += 2; if (idx > raw->curlen) goto fail_len; return true; fail_len: DRM_DEBUG_KMS("query payload parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_power_updown_phy_ack(struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { int idx = 1; repmsg->u.port_number.port_number = (raw->msg[idx] >> 4) & 0xf; idx++; if (idx > raw->curlen) { DRM_DEBUG_KMS("power up/down phy parse length fail %d %d\n", idx, raw->curlen); return false; } return true; } static bool drm_dp_sideband_parse_query_stream_enc_status( struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *repmsg) { struct drm_dp_query_stream_enc_status_ack_reply *reply; reply = &repmsg->u.enc_status; reply->stream_id = raw->msg[3]; reply->reply_signed = raw->msg[2] & BIT(0); /* * NOTE: It's my impression from reading the spec that the below parsing * is correct. However I noticed while testing with an HDCP 1.4 display * through an HDCP 2.2 hub that only bit 3 was set. In that case, I * would expect both bits to be set. So keep the parsing following the * spec, but beware reality might not match the spec (at least for some * configurations). */ reply->hdcp_1x_device_present = raw->msg[2] & BIT(4); reply->hdcp_2x_device_present = raw->msg[2] & BIT(3); reply->query_capable_device_present = raw->msg[2] & BIT(5); reply->legacy_device_present = raw->msg[2] & BIT(6); reply->unauthorizable_device_present = raw->msg[2] & BIT(7); reply->auth_completed = !!(raw->msg[1] & BIT(3)); reply->encryption_enabled = !!(raw->msg[1] & BIT(4)); reply->repeater_present = !!(raw->msg[1] & BIT(5)); reply->state = (raw->msg[1] & GENMASK(7, 6)) >> 6; return true; } static bool drm_dp_sideband_parse_reply(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_reply_body *msg) { memset(msg, 0, sizeof(*msg)); msg->reply_type = (raw->msg[0] & 0x80) >> 7; msg->req_type = (raw->msg[0] & 0x7f); if (msg->reply_type == DP_SIDEBAND_REPLY_NAK) { memcpy(msg->u.nak.guid, &raw->msg[1], 16); msg->u.nak.reason = raw->msg[17]; msg->u.nak.nak_data = raw->msg[18]; return false; } switch (msg->req_type) { case DP_LINK_ADDRESS: return drm_dp_sideband_parse_link_address(mgr, raw, msg); case DP_QUERY_PAYLOAD: return drm_dp_sideband_parse_query_payload_ack(raw, msg); case DP_REMOTE_DPCD_READ: return drm_dp_sideband_parse_remote_dpcd_read(raw, msg); case DP_REMOTE_DPCD_WRITE: return drm_dp_sideband_parse_remote_dpcd_write(raw, msg); case DP_REMOTE_I2C_READ: return drm_dp_sideband_parse_remote_i2c_read_ack(raw, msg); case DP_REMOTE_I2C_WRITE: return true; /* since there's nothing to parse */ case DP_ENUM_PATH_RESOURCES: return drm_dp_sideband_parse_enum_path_resources_ack(raw, msg); case DP_ALLOCATE_PAYLOAD: return drm_dp_sideband_parse_allocate_payload_ack(raw, msg); case DP_POWER_DOWN_PHY: case DP_POWER_UP_PHY: return drm_dp_sideband_parse_power_updown_phy_ack(raw, msg); case DP_CLEAR_PAYLOAD_ID_TABLE: return true; /* since there's nothing to parse */ case DP_QUERY_STREAM_ENC_STATUS: return drm_dp_sideband_parse_query_stream_enc_status(raw, msg); default: drm_err(mgr->dev, "Got unknown reply 0x%02x (%s)\n", msg->req_type, drm_dp_mst_req_type_str(msg->req_type)); return false; } } static bool drm_dp_sideband_parse_connection_status_notify(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_req_body *msg) { int idx = 1; msg->u.conn_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; idx++; if (idx > raw->curlen) goto fail_len; memcpy(msg->u.conn_stat.guid, &raw->msg[idx], 16); idx += 16; if (idx > raw->curlen) goto fail_len; msg->u.conn_stat.legacy_device_plug_status = (raw->msg[idx] >> 6) & 0x1; msg->u.conn_stat.displayport_device_plug_status = (raw->msg[idx] >> 5) & 0x1; msg->u.conn_stat.message_capability_status = (raw->msg[idx] >> 4) & 0x1; msg->u.conn_stat.input_port = (raw->msg[idx] >> 3) & 0x1; msg->u.conn_stat.peer_device_type = (raw->msg[idx] & 0x7); idx++; return true; fail_len: drm_dbg_kms(mgr->dev, "connection status reply parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_resource_status_notify(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_req_body *msg) { int idx = 1; msg->u.resource_stat.port_number = (raw->msg[idx] & 0xf0) >> 4; idx++; if (idx > raw->curlen) goto fail_len; memcpy(msg->u.resource_stat.guid, &raw->msg[idx], 16); idx += 16; if (idx > raw->curlen) goto fail_len; msg->u.resource_stat.available_pbn = (raw->msg[idx] << 8) | (raw->msg[idx + 1]); idx++; return true; fail_len: drm_dbg_kms(mgr->dev, "resource status reply parse length fail %d %d\n", idx, raw->curlen); return false; } static bool drm_dp_sideband_parse_req(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_rx *raw, struct drm_dp_sideband_msg_req_body *msg) { memset(msg, 0, sizeof(*msg)); msg->req_type = (raw->msg[0] & 0x7f); switch (msg->req_type) { case DP_CONNECTION_STATUS_NOTIFY: return drm_dp_sideband_parse_connection_status_notify(mgr, raw, msg); case DP_RESOURCE_STATUS_NOTIFY: return drm_dp_sideband_parse_resource_status_notify(mgr, raw, msg); default: drm_err(mgr->dev, "Got unknown request 0x%02x (%s)\n", msg->req_type, drm_dp_mst_req_type_str(msg->req_type)); return false; } } static void build_dpcd_write(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes, u8 *bytes) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_REMOTE_DPCD_WRITE; req.u.dpcd_write.port_number = port_num; req.u.dpcd_write.dpcd_address = offset; req.u.dpcd_write.num_bytes = num_bytes; req.u.dpcd_write.bytes = bytes; drm_dp_encode_sideband_req(&req, msg); } static void build_link_address(struct drm_dp_sideband_msg_tx *msg) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_LINK_ADDRESS; drm_dp_encode_sideband_req(&req, msg); } static void build_clear_payload_id_table(struct drm_dp_sideband_msg_tx *msg) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_CLEAR_PAYLOAD_ID_TABLE; drm_dp_encode_sideband_req(&req, msg); msg->path_msg = true; } static int build_enum_path_resources(struct drm_dp_sideband_msg_tx *msg, int port_num) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_ENUM_PATH_RESOURCES; req.u.port_num.port_number = port_num; drm_dp_encode_sideband_req(&req, msg); msg->path_msg = true; return 0; } static void build_allocate_payload(struct drm_dp_sideband_msg_tx *msg, int port_num, u8 vcpi, uint16_t pbn, u8 number_sdp_streams, u8 *sdp_stream_sink) { struct drm_dp_sideband_msg_req_body req; memset(&req, 0, sizeof(req)); req.req_type = DP_ALLOCATE_PAYLOAD; req.u.allocate_payload.port_number = port_num; req.u.allocate_payload.vcpi = vcpi; req.u.allocate_payload.pbn = pbn; req.u.allocate_payload.number_sdp_streams = number_sdp_streams; memcpy(req.u.allocate_payload.sdp_stream_sink, sdp_stream_sink, number_sdp_streams); drm_dp_encode_sideband_req(&req, msg); msg->path_msg = true; } static void build_power_updown_phy(struct drm_dp_sideband_msg_tx *msg, int port_num, bool power_up) { struct drm_dp_sideband_msg_req_body req; if (power_up) req.req_type = DP_POWER_UP_PHY; else req.req_type = DP_POWER_DOWN_PHY; req.u.port_num.port_number = port_num; drm_dp_encode_sideband_req(&req, msg); msg->path_msg = true; } static int build_query_stream_enc_status(struct drm_dp_sideband_msg_tx *msg, u8 stream_id, u8 *q_id) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_QUERY_STREAM_ENC_STATUS; req.u.enc_status.stream_id = stream_id; memcpy(req.u.enc_status.client_id, q_id, sizeof(req.u.enc_status.client_id)); req.u.enc_status.stream_event = 0; req.u.enc_status.valid_stream_event = false; req.u.enc_status.stream_behavior = 0; req.u.enc_status.valid_stream_behavior = false; drm_dp_encode_sideband_req(&req, msg); return 0; } static bool check_txmsg_state(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_tx *txmsg) { unsigned int state; /* * All updates to txmsg->state are protected by mgr->qlock, and the two * cases we check here are terminal states. For those the barriers * provided by the wake_up/wait_event pair are enough. */ state = READ_ONCE(txmsg->state); return (state == DRM_DP_SIDEBAND_TX_RX || state == DRM_DP_SIDEBAND_TX_TIMEOUT); } static int drm_dp_mst_wait_tx_reply(struct drm_dp_mst_branch *mstb, struct drm_dp_sideband_msg_tx *txmsg) { struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; unsigned long wait_timeout = msecs_to_jiffies(4000); unsigned long wait_expires = jiffies + wait_timeout; int ret; for (;;) { /* * If the driver provides a way for this, change to * poll-waiting for the MST reply interrupt if we didn't receive * it for 50 msec. This would cater for cases where the HPD * pulse signal got lost somewhere, even though the sink raised * the corresponding MST interrupt correctly. One example is the * Club 3D CAC-1557 TypeC -> DP adapter which for some reason * filters out short pulses with a duration less than ~540 usec. * * The poll period is 50 msec to avoid missing an interrupt * after the sink has cleared it (after a 110msec timeout * since it raised the interrupt). */ ret = wait_event_timeout(mgr->tx_waitq, check_txmsg_state(mgr, txmsg), mgr->cbs->poll_hpd_irq ? msecs_to_jiffies(50) : wait_timeout); if (ret || !mgr->cbs->poll_hpd_irq || time_after(jiffies, wait_expires)) break; mgr->cbs->poll_hpd_irq(mgr); } mutex_lock(&mgr->qlock); if (ret > 0) { if (txmsg->state == DRM_DP_SIDEBAND_TX_TIMEOUT) { ret = -EIO; goto out; } } else { drm_dbg_kms(mgr->dev, "timedout msg send %p %d %d\n", txmsg, txmsg->state, txmsg->seqno); /* dump some state */ ret = -EIO; /* remove from q */ if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED || txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || txmsg->state == DRM_DP_SIDEBAND_TX_SENT) list_del(&txmsg->next); } out: if (unlikely(ret == -EIO) && drm_debug_enabled(DRM_UT_DP)) { struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP, DBG_PREFIX); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); } mutex_unlock(&mgr->qlock); drm_dp_mst_kick_tx(mgr); return ret; } static struct drm_dp_mst_branch *drm_dp_add_mst_branch_device(u8 lct, u8 *rad) { struct drm_dp_mst_branch *mstb; mstb = kzalloc(sizeof(*mstb), GFP_KERNEL); if (!mstb) return NULL; mstb->lct = lct; if (lct > 1) memcpy(mstb->rad, rad, lct / 2); INIT_LIST_HEAD(&mstb->ports); kref_init(&mstb->topology_kref); kref_init(&mstb->malloc_kref); return mstb; } static void drm_dp_free_mst_branch_device(struct kref *kref) { struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, malloc_kref); if (mstb->port_parent) drm_dp_mst_put_port_malloc(mstb->port_parent); kfree(mstb); } /** * DOC: Branch device and port refcounting * * Topology refcount overview * ~~~~~~~~~~~~~~~~~~~~~~~~~~ * * The refcounting schemes for &struct drm_dp_mst_branch and &struct * drm_dp_mst_port are somewhat unusual. Both ports and branch devices have * two different kinds of refcounts: topology refcounts, and malloc refcounts. * * Topology refcounts are not exposed to drivers, and are handled internally * by the DP MST helpers. The helpers use them in order to prevent the * in-memory topology state from being changed in the middle of critical * operations like changing the internal state of payload allocations. This * means each branch and port will be considered to be connected to the rest * of the topology until its topology refcount reaches zero. Additionally, * for ports this means that their associated &struct drm_connector will stay * registered with userspace until the port's refcount reaches 0. * * Malloc refcount overview * ~~~~~~~~~~~~~~~~~~~~~~~~ * * Malloc references are used to keep a &struct drm_dp_mst_port or &struct * drm_dp_mst_branch allocated even after all of its topology references have * been dropped, so that the driver or MST helpers can safely access each * branch's last known state before it was disconnected from the topology. * When the malloc refcount of a port or branch reaches 0, the memory * allocation containing the &struct drm_dp_mst_branch or &struct * drm_dp_mst_port respectively will be freed. * * For &struct drm_dp_mst_branch, malloc refcounts are not currently exposed * to drivers. As of writing this documentation, there are no drivers that * have a usecase for accessing &struct drm_dp_mst_branch outside of the MST * helpers. Exposing this API to drivers in a race-free manner would take more * tweaking of the refcounting scheme, however patches are welcome provided * there is a legitimate driver usecase for this. * * Refcount relationships in a topology * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Let's take a look at why the relationship between topology and malloc * refcounts is designed the way it is. * * .. kernel-figure:: dp-mst/topology-figure-1.dot * * An example of topology and malloc refs in a DP MST topology with two * active payloads. Topology refcount increments are indicated by solid * lines, and malloc refcount increments are indicated by dashed lines. * Each starts from the branch which incremented the refcount, and ends at * the branch to which the refcount belongs to, i.e. the arrow points the * same way as the C pointers used to reference a structure. * * As you can see in the above figure, every branch increments the topology * refcount of its children, and increments the malloc refcount of its * parent. Additionally, every payload increments the malloc refcount of its * assigned port by 1. * * So, what would happen if MSTB #3 from the above figure was unplugged from * the system, but the driver hadn't yet removed payload #2 from port #3? The * topology would start to look like the figure below. * * .. kernel-figure:: dp-mst/topology-figure-2.dot * * Ports and branch devices which have been released from memory are * colored grey, and references which have been removed are colored red. * * Whenever a port or branch device's topology refcount reaches zero, it will * decrement the topology refcounts of all its children, the malloc refcount * of its parent, and finally its own malloc refcount. For MSTB #4 and port * #4, this means they both have been disconnected from the topology and freed * from memory. But, because payload #2 is still holding a reference to port * #3, port #3 is removed from the topology but its &struct drm_dp_mst_port * is still accessible from memory. This also means port #3 has not yet * decremented the malloc refcount of MSTB #3, so its &struct * drm_dp_mst_branch will also stay allocated in memory until port #3's * malloc refcount reaches 0. * * This relationship is necessary because in order to release payload #2, we * need to be able to figure out the last relative of port #3 that's still * connected to the topology. In this case, we would travel up the topology as * shown below. * * .. kernel-figure:: dp-mst/topology-figure-3.dot * * And finally, remove payload #2 by communicating with port #2 through * sideband transactions. */ /** * drm_dp_mst_get_mstb_malloc() - Increment the malloc refcount of a branch * device * @mstb: The &struct drm_dp_mst_branch to increment the malloc refcount of * * Increments &drm_dp_mst_branch.malloc_kref. When * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb * will be released and @mstb may no longer be used. * * See also: drm_dp_mst_put_mstb_malloc() */ static void drm_dp_mst_get_mstb_malloc(struct drm_dp_mst_branch *mstb) { kref_get(&mstb->malloc_kref); drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref)); } /** * drm_dp_mst_put_mstb_malloc() - Decrement the malloc refcount of a branch * device * @mstb: The &struct drm_dp_mst_branch to decrement the malloc refcount of * * Decrements &drm_dp_mst_branch.malloc_kref. When * &drm_dp_mst_branch.malloc_kref reaches 0, the memory allocation for @mstb * will be released and @mstb may no longer be used. * * See also: drm_dp_mst_get_mstb_malloc() */ static void drm_dp_mst_put_mstb_malloc(struct drm_dp_mst_branch *mstb) { drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->malloc_kref) - 1); kref_put(&mstb->malloc_kref, drm_dp_free_mst_branch_device); } static void drm_dp_free_mst_port(struct kref *kref) { struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, malloc_kref); drm_dp_mst_put_mstb_malloc(port->parent); kfree(port); } /** * drm_dp_mst_get_port_malloc() - Increment the malloc refcount of an MST port * @port: The &struct drm_dp_mst_port to increment the malloc refcount of * * Increments &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref * reaches 0, the memory allocation for @port will be released and @port may * no longer be used. * * Because @port could potentially be freed at any time by the DP MST helpers * if &drm_dp_mst_port.malloc_kref reaches 0, including during a call to this * function, drivers that which to make use of &struct drm_dp_mst_port should * ensure that they grab at least one main malloc reference to their MST ports * in &drm_dp_mst_topology_cbs.add_connector. This callback is called before * there is any chance for &drm_dp_mst_port.malloc_kref to reach 0. * * See also: drm_dp_mst_put_port_malloc() */ void drm_dp_mst_get_port_malloc(struct drm_dp_mst_port *port) { kref_get(&port->malloc_kref); drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref)); } EXPORT_SYMBOL(drm_dp_mst_get_port_malloc); /** * drm_dp_mst_put_port_malloc() - Decrement the malloc refcount of an MST port * @port: The &struct drm_dp_mst_port to decrement the malloc refcount of * * Decrements &drm_dp_mst_port.malloc_kref. When &drm_dp_mst_port.malloc_kref * reaches 0, the memory allocation for @port will be released and @port may * no longer be used. * * See also: drm_dp_mst_get_port_malloc() */ void drm_dp_mst_put_port_malloc(struct drm_dp_mst_port *port) { drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->malloc_kref) - 1); kref_put(&port->malloc_kref, drm_dp_free_mst_port); } EXPORT_SYMBOL(drm_dp_mst_put_port_malloc); #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) #define STACK_DEPTH 8 static noinline void __topology_ref_save(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_ref_history *history, enum drm_dp_mst_topology_ref_type type) { struct drm_dp_mst_topology_ref_entry *entry = NULL; depot_stack_handle_t backtrace; ulong stack_entries[STACK_DEPTH]; uint n; int i; n = stack_trace_save(stack_entries, ARRAY_SIZE(stack_entries), 1); backtrace = stack_depot_save(stack_entries, n, GFP_KERNEL); if (!backtrace) return; /* Try to find an existing entry for this backtrace */ for (i = 0; i < history->len; i++) { if (history->entries[i].backtrace == backtrace) { entry = &history->entries[i]; break; } } /* Otherwise add one */ if (!entry) { struct drm_dp_mst_topology_ref_entry *new; int new_len = history->len + 1; new = krealloc(history->entries, sizeof(*new) * new_len, GFP_KERNEL); if (!new) return; entry = &new[history->len]; history->len = new_len; history->entries = new; entry->backtrace = backtrace; entry->type = type; entry->count = 0; } entry->count++; entry->ts_nsec = ktime_get_ns(); } static int topology_ref_history_cmp(const void *a, const void *b) { const struct drm_dp_mst_topology_ref_entry *entry_a = a, *entry_b = b; if (entry_a->ts_nsec > entry_b->ts_nsec) return 1; else if (entry_a->ts_nsec < entry_b->ts_nsec) return -1; else return 0; } static inline const char * topology_ref_type_to_str(enum drm_dp_mst_topology_ref_type type) { if (type == DRM_DP_MST_TOPOLOGY_REF_GET) return "get"; else return "put"; } static void __dump_topology_ref_history(struct drm_device *drm, struct drm_dp_mst_topology_ref_history *history, void *ptr, const char *type_str) { struct drm_printer p = drm_dbg_printer(drm, DRM_UT_DP, DBG_PREFIX); char *buf = kzalloc(PAGE_SIZE, GFP_KERNEL); int i; if (!buf) return; if (!history->len) goto out; /* First, sort the list so that it goes from oldest to newest * reference entry */ sort(history->entries, history->len, sizeof(*history->entries), topology_ref_history_cmp, NULL); drm_printf(&p, "%s (%p) topology count reached 0, dumping history:\n", type_str, ptr); for (i = 0; i < history->len; i++) { const struct drm_dp_mst_topology_ref_entry *entry = &history->entries[i]; u64 ts_nsec = entry->ts_nsec; u32 rem_nsec = do_div(ts_nsec, 1000000000); stack_depot_snprint(entry->backtrace, buf, PAGE_SIZE, 4); drm_printf(&p, " %d %ss (last at %5llu.%06u):\n%s", entry->count, topology_ref_type_to_str(entry->type), ts_nsec, rem_nsec / 1000, buf); } /* Now free the history, since this is the only time we expose it */ kfree(history->entries); out: kfree(buf); } static __always_inline void drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) { __dump_topology_ref_history(mstb->mgr->dev, &mstb->topology_ref_history, mstb, "MSTB"); } static __always_inline void drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) { __dump_topology_ref_history(port->mgr->dev, &port->topology_ref_history, port, "Port"); } static __always_inline void save_mstb_topology_ref(struct drm_dp_mst_branch *mstb, enum drm_dp_mst_topology_ref_type type) { __topology_ref_save(mstb->mgr, &mstb->topology_ref_history, type); } static __always_inline void save_port_topology_ref(struct drm_dp_mst_port *port, enum drm_dp_mst_topology_ref_type type) { __topology_ref_save(port->mgr, &port->topology_ref_history, type); } static inline void topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr) { mutex_lock(&mgr->topology_ref_history_lock); } static inline void topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr) { mutex_unlock(&mgr->topology_ref_history_lock); } #else static inline void topology_ref_history_lock(struct drm_dp_mst_topology_mgr *mgr) {} static inline void topology_ref_history_unlock(struct drm_dp_mst_topology_mgr *mgr) {} static inline void drm_dp_mst_dump_mstb_topology_history(struct drm_dp_mst_branch *mstb) {} static inline void drm_dp_mst_dump_port_topology_history(struct drm_dp_mst_port *port) {} #define save_mstb_topology_ref(mstb, type) #define save_port_topology_ref(port, type) #endif struct drm_dp_mst_atomic_payload * drm_atomic_get_mst_payload_state(struct drm_dp_mst_topology_state *state, struct drm_dp_mst_port *port) { struct drm_dp_mst_atomic_payload *payload; list_for_each_entry(payload, &state->payloads, next) if (payload->port == port) return payload; return NULL; } EXPORT_SYMBOL(drm_atomic_get_mst_payload_state); static void drm_dp_destroy_mst_branch_device(struct kref *kref) { struct drm_dp_mst_branch *mstb = container_of(kref, struct drm_dp_mst_branch, topology_kref); struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; drm_dp_mst_dump_mstb_topology_history(mstb); INIT_LIST_HEAD(&mstb->destroy_next); /* * This can get called under mgr->mutex, so we need to perform the * actual destruction of the mstb in another worker */ mutex_lock(&mgr->delayed_destroy_lock); list_add(&mstb->destroy_next, &mgr->destroy_branch_device_list); mutex_unlock(&mgr->delayed_destroy_lock); queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** * drm_dp_mst_topology_try_get_mstb() - Increment the topology refcount of a * branch device unless it's zero * @mstb: &struct drm_dp_mst_branch to increment the topology refcount of * * Attempts to grab a topology reference to @mstb, if it hasn't yet been * removed from the topology (e.g. &drm_dp_mst_branch.topology_kref has * reached 0). Holding a topology reference implies that a malloc reference * will be held to @mstb as long as the user holds the topology reference. * * Care should be taken to ensure that the user has at least one malloc * reference to @mstb. If you already have a topology reference to @mstb, you * should use drm_dp_mst_topology_get_mstb() instead. * * See also: * drm_dp_mst_topology_get_mstb() * drm_dp_mst_topology_put_mstb() * * Returns: * * 1: A topology reference was grabbed successfully * * 0: @port is no longer in the topology, no reference was grabbed */ static int __must_check drm_dp_mst_topology_try_get_mstb(struct drm_dp_mst_branch *mstb) { int ret; topology_ref_history_lock(mstb->mgr); ret = kref_get_unless_zero(&mstb->topology_kref); if (ret) { drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref)); save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET); } topology_ref_history_unlock(mstb->mgr); return ret; } /** * drm_dp_mst_topology_get_mstb() - Increment the topology refcount of a * branch device * @mstb: The &struct drm_dp_mst_branch to increment the topology refcount of * * Increments &drm_dp_mst_branch.topology_refcount without checking whether or * not it's already reached 0. This is only valid to use in scenarios where * you are already guaranteed to have at least one active topology reference * to @mstb. Otherwise, drm_dp_mst_topology_try_get_mstb() must be used. * * See also: * drm_dp_mst_topology_try_get_mstb() * drm_dp_mst_topology_put_mstb() */ static void drm_dp_mst_topology_get_mstb(struct drm_dp_mst_branch *mstb) { topology_ref_history_lock(mstb->mgr); save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_GET); WARN_ON(kref_read(&mstb->topology_kref) == 0); kref_get(&mstb->topology_kref); drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref)); topology_ref_history_unlock(mstb->mgr); } /** * drm_dp_mst_topology_put_mstb() - release a topology reference to a branch * device * @mstb: The &struct drm_dp_mst_branch to release the topology reference from * * Releases a topology reference from @mstb by decrementing * &drm_dp_mst_branch.topology_kref. * * See also: * drm_dp_mst_topology_try_get_mstb() * drm_dp_mst_topology_get_mstb() */ static void drm_dp_mst_topology_put_mstb(struct drm_dp_mst_branch *mstb) { topology_ref_history_lock(mstb->mgr); drm_dbg(mstb->mgr->dev, "mstb %p (%d)\n", mstb, kref_read(&mstb->topology_kref) - 1); save_mstb_topology_ref(mstb, DRM_DP_MST_TOPOLOGY_REF_PUT); topology_ref_history_unlock(mstb->mgr); kref_put(&mstb->topology_kref, drm_dp_destroy_mst_branch_device); } static void drm_dp_destroy_port(struct kref *kref) { struct drm_dp_mst_port *port = container_of(kref, struct drm_dp_mst_port, topology_kref); struct drm_dp_mst_topology_mgr *mgr = port->mgr; drm_dp_mst_dump_port_topology_history(port); /* There's nothing that needs locking to destroy an input port yet */ if (port->input) { drm_dp_mst_put_port_malloc(port); return; } drm_edid_free(port->cached_edid); /* * we can't destroy the connector here, as we might be holding the * mode_config.mutex from an EDID retrieval */ mutex_lock(&mgr->delayed_destroy_lock); list_add(&port->next, &mgr->destroy_port_list); mutex_unlock(&mgr->delayed_destroy_lock); queue_work(mgr->delayed_destroy_wq, &mgr->delayed_destroy_work); } /** * drm_dp_mst_topology_try_get_port() - Increment the topology refcount of a * port unless it's zero * @port: &struct drm_dp_mst_port to increment the topology refcount of * * Attempts to grab a topology reference to @port, if it hasn't yet been * removed from the topology (e.g. &drm_dp_mst_port.topology_kref has reached * 0). Holding a topology reference implies that a malloc reference will be * held to @port as long as the user holds the topology reference. * * Care should be taken to ensure that the user has at least one malloc * reference to @port. If you already have a topology reference to @port, you * should use drm_dp_mst_topology_get_port() instead. * * See also: * drm_dp_mst_topology_get_port() * drm_dp_mst_topology_put_port() * * Returns: * * 1: A topology reference was grabbed successfully * * 0: @port is no longer in the topology, no reference was grabbed */ static int __must_check drm_dp_mst_topology_try_get_port(struct drm_dp_mst_port *port) { int ret; topology_ref_history_lock(port->mgr); ret = kref_get_unless_zero(&port->topology_kref); if (ret) { drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref)); save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET); } topology_ref_history_unlock(port->mgr); return ret; } /** * drm_dp_mst_topology_get_port() - Increment the topology refcount of a port * @port: The &struct drm_dp_mst_port to increment the topology refcount of * * Increments &drm_dp_mst_port.topology_refcount without checking whether or * not it's already reached 0. This is only valid to use in scenarios where * you are already guaranteed to have at least one active topology reference * to @port. Otherwise, drm_dp_mst_topology_try_get_port() must be used. * * See also: * drm_dp_mst_topology_try_get_port() * drm_dp_mst_topology_put_port() */ static void drm_dp_mst_topology_get_port(struct drm_dp_mst_port *port) { topology_ref_history_lock(port->mgr); WARN_ON(kref_read(&port->topology_kref) == 0); kref_get(&port->topology_kref); drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref)); save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_GET); topology_ref_history_unlock(port->mgr); } /** * drm_dp_mst_topology_put_port() - release a topology reference to a port * @port: The &struct drm_dp_mst_port to release the topology reference from * * Releases a topology reference from @port by decrementing * &drm_dp_mst_port.topology_kref. * * See also: * drm_dp_mst_topology_try_get_port() * drm_dp_mst_topology_get_port() */ static void drm_dp_mst_topology_put_port(struct drm_dp_mst_port *port) { topology_ref_history_lock(port->mgr); drm_dbg(port->mgr->dev, "port %p (%d)\n", port, kref_read(&port->topology_kref) - 1); save_port_topology_ref(port, DRM_DP_MST_TOPOLOGY_REF_PUT); topology_ref_history_unlock(port->mgr); kref_put(&port->topology_kref, drm_dp_destroy_port); } static struct drm_dp_mst_branch * drm_dp_mst_topology_get_mstb_validated_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_branch *to_find) { struct drm_dp_mst_port *port; struct drm_dp_mst_branch *rmstb; if (to_find == mstb) return mstb; list_for_each_entry(port, &mstb->ports, next) { if (port->mstb) { rmstb = drm_dp_mst_topology_get_mstb_validated_locked( port->mstb, to_find); if (rmstb) return rmstb; } } return NULL; } static struct drm_dp_mst_branch * drm_dp_mst_topology_get_mstb_validated(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) { struct drm_dp_mst_branch *rmstb = NULL; mutex_lock(&mgr->lock); if (mgr->mst_primary) { rmstb = drm_dp_mst_topology_get_mstb_validated_locked( mgr->mst_primary, mstb); if (rmstb && !drm_dp_mst_topology_try_get_mstb(rmstb)) rmstb = NULL; } mutex_unlock(&mgr->lock); return rmstb; } static struct drm_dp_mst_port * drm_dp_mst_topology_get_port_validated_locked(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *to_find) { struct drm_dp_mst_port *port, *mport; list_for_each_entry(port, &mstb->ports, next) { if (port == to_find) return port; if (port->mstb) { mport = drm_dp_mst_topology_get_port_validated_locked( port->mstb, to_find); if (mport) return mport; } } return NULL; } static struct drm_dp_mst_port * drm_dp_mst_topology_get_port_validated(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { struct drm_dp_mst_port *rport = NULL; mutex_lock(&mgr->lock); if (mgr->mst_primary) { rport = drm_dp_mst_topology_get_port_validated_locked( mgr->mst_primary, port); if (rport && !drm_dp_mst_topology_try_get_port(rport)) rport = NULL; } mutex_unlock(&mgr->lock); return rport; } static struct drm_dp_mst_port *drm_dp_get_port(struct drm_dp_mst_branch *mstb, u8 port_num) { struct drm_dp_mst_port *port; int ret; list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { ret = drm_dp_mst_topology_try_get_port(port); return ret ? port : NULL; } } return NULL; } /* * calculate a new RAD for this MST branch device * if parent has an LCT of 2 then it has 1 nibble of RAD, * if parent has an LCT of 3 then it has 2 nibbles of RAD, */ static u8 drm_dp_calculate_rad(struct drm_dp_mst_port *port, u8 *rad) { int parent_lct = port->parent->lct; int shift = 4; int idx = (parent_lct - 1) / 2; if (parent_lct > 1) { memcpy(rad, port->parent->rad, idx + 1); shift = (parent_lct % 2) ? 4 : 0; } else rad[0] = 0; rad[idx] |= port->port_num << shift; return parent_lct + 1; } static bool drm_dp_mst_is_end_device(u8 pdt, bool mcs) { switch (pdt) { case DP_PEER_DEVICE_DP_LEGACY_CONV: case DP_PEER_DEVICE_SST_SINK: return true; case DP_PEER_DEVICE_MST_BRANCHING: /* For sst branch device */ if (!mcs) return true; return false; } return true; } static int drm_dp_port_set_pdt(struct drm_dp_mst_port *port, u8 new_pdt, bool new_mcs) { struct drm_dp_mst_topology_mgr *mgr = port->mgr; struct drm_dp_mst_branch *mstb; u8 rad[8], lct; int ret = 0; if (port->pdt == new_pdt && port->mcs == new_mcs) return 0; /* Teardown the old pdt, if there is one */ if (port->pdt != DP_PEER_DEVICE_NONE) { if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { /* * If the new PDT would also have an i2c bus, * don't bother with reregistering it */ if (new_pdt != DP_PEER_DEVICE_NONE && drm_dp_mst_is_end_device(new_pdt, new_mcs)) { port->pdt = new_pdt; port->mcs = new_mcs; return 0; } /* remove i2c over sideband */ drm_dp_mst_unregister_i2c_bus(port); } else { mutex_lock(&mgr->lock); drm_dp_mst_topology_put_mstb(port->mstb); port->mstb = NULL; mutex_unlock(&mgr->lock); } } port->pdt = new_pdt; port->mcs = new_mcs; if (port->pdt != DP_PEER_DEVICE_NONE) { if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { /* add i2c over sideband */ ret = drm_dp_mst_register_i2c_bus(port); } else { lct = drm_dp_calculate_rad(port, rad); mstb = drm_dp_add_mst_branch_device(lct, rad); if (!mstb) { ret = -ENOMEM; drm_err(mgr->dev, "Failed to create MSTB for port %p", port); goto out; } mutex_lock(&mgr->lock); port->mstb = mstb; mstb->mgr = port->mgr; mstb->port_parent = port; /* * Make sure this port's memory allocation stays * around until its child MSTB releases it */ drm_dp_mst_get_port_malloc(port); mutex_unlock(&mgr->lock); /* And make sure we send a link address for this */ ret = 1; } } out: if (ret < 0) port->pdt = DP_PEER_DEVICE_NONE; return ret; } /** * drm_dp_mst_dpcd_read() - read a series of bytes from the DPCD via sideband * @aux: Fake sideband AUX CH * @offset: address of the (first) register to read * @buffer: buffer to store the register values * @size: number of bytes in @buffer * * Performs the same functionality for remote devices via * sideband messaging as drm_dp_dpcd_read() does for local * devices via actual AUX CH. * * Return: Number of bytes read, or negative error code on failure. */ ssize_t drm_dp_mst_dpcd_read(struct drm_dp_aux *aux, unsigned int offset, void *buffer, size_t size) { struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); return drm_dp_send_dpcd_read(port->mgr, port, offset, size, buffer); } /** * drm_dp_mst_dpcd_write() - write a series of bytes to the DPCD via sideband * @aux: Fake sideband AUX CH * @offset: address of the (first) register to write * @buffer: buffer containing the values to write * @size: number of bytes in @buffer * * Performs the same functionality for remote devices via * sideband messaging as drm_dp_dpcd_write() does for local * devices via actual AUX CH. * * Return: number of bytes written on success, negative error code on failure. */ ssize_t drm_dp_mst_dpcd_write(struct drm_dp_aux *aux, unsigned int offset, void *buffer, size_t size) { struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); return drm_dp_send_dpcd_write(port->mgr, port, offset, size, buffer); } static int drm_dp_check_mstb_guid(struct drm_dp_mst_branch *mstb, u8 *guid) { int ret = 0; memcpy(mstb->guid, guid, 16); if (!drm_dp_validate_guid(mstb->mgr, mstb->guid)) { if (mstb->port_parent) { ret = drm_dp_send_dpcd_write(mstb->mgr, mstb->port_parent, DP_GUID, 16, mstb->guid); } else { ret = drm_dp_dpcd_write(mstb->mgr->aux, DP_GUID, mstb->guid, 16); } } if (ret < 16 && ret > 0) return -EPROTO; return ret == 16 ? 0 : ret; } static void build_mst_prop_path(const struct drm_dp_mst_branch *mstb, int pnum, char *proppath, size_t proppath_size) { int i; char temp[8]; snprintf(proppath, proppath_size, "mst:%d", mstb->mgr->conn_base_id); for (i = 0; i < (mstb->lct - 1); i++) { int shift = (i % 2) ? 0 : 4; int port_num = (mstb->rad[i / 2] >> shift) & 0xf; snprintf(temp, sizeof(temp), "-%d", port_num); strlcat(proppath, temp, proppath_size); } snprintf(temp, sizeof(temp), "-%d", pnum); strlcat(proppath, temp, proppath_size); } /** * drm_dp_mst_connector_late_register() - Late MST connector registration * @connector: The MST connector * @port: The MST port for this connector * * Helper to register the remote aux device for this MST port. Drivers should * call this from their mst connector's late_register hook to enable MST aux * devices. * * Return: 0 on success, negative error code on failure. */ int drm_dp_mst_connector_late_register(struct drm_connector *connector, struct drm_dp_mst_port *port) { drm_dbg_kms(port->mgr->dev, "registering %s remote bus for %s\n", port->aux.name, connector->kdev->kobj.name); port->aux.dev = connector->kdev; return drm_dp_aux_register_devnode(&port->aux); } EXPORT_SYMBOL(drm_dp_mst_connector_late_register); /** * drm_dp_mst_connector_early_unregister() - Early MST connector unregistration * @connector: The MST connector * @port: The MST port for this connector * * Helper to unregister the remote aux device for this MST port, registered by * drm_dp_mst_connector_late_register(). Drivers should call this from their mst * connector's early_unregister hook. */ void drm_dp_mst_connector_early_unregister(struct drm_connector *connector, struct drm_dp_mst_port *port) { drm_dbg_kms(port->mgr->dev, "unregistering %s remote bus for %s\n", port->aux.name, connector->kdev->kobj.name); drm_dp_aux_unregister_devnode(&port->aux); } EXPORT_SYMBOL(drm_dp_mst_connector_early_unregister); static void drm_dp_mst_port_add_connector(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *port) { struct drm_dp_mst_topology_mgr *mgr = port->mgr; char proppath[255]; int ret; build_mst_prop_path(mstb, port->port_num, proppath, sizeof(proppath)); port->connector = mgr->cbs->add_connector(mgr, port, proppath); if (!port->connector) { ret = -ENOMEM; goto error; } if (port->pdt != DP_PEER_DEVICE_NONE && drm_dp_mst_is_end_device(port->pdt, port->mcs) && drm_dp_mst_port_is_logical(port)) port->cached_edid = drm_edid_read_ddc(port->connector, &port->aux.ddc); drm_connector_register(port->connector); return; error: drm_err(mgr->dev, "Failed to create connector for port %p: %d\n", port, ret); } /* * Drop a topology reference, and unlink the port from the in-memory topology * layout */ static void drm_dp_mst_topology_unlink_port(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { mutex_lock(&mgr->lock); port->parent->num_ports--; list_del(&port->next); mutex_unlock(&mgr->lock); drm_dp_mst_topology_put_port(port); } static struct drm_dp_mst_port * drm_dp_mst_add_port(struct drm_device *dev, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb, u8 port_number) { struct drm_dp_mst_port *port = kzalloc(sizeof(*port), GFP_KERNEL); if (!port) return NULL; kref_init(&port->topology_kref); kref_init(&port->malloc_kref); port->parent = mstb; port->port_num = port_number; port->mgr = mgr; port->aux.name = "DPMST"; port->aux.dev = dev->dev; port->aux.is_remote = true; /* initialize the MST downstream port's AUX crc work queue */ port->aux.drm_dev = dev; drm_dp_remote_aux_init(&port->aux); /* * Make sure the memory allocation for our parent branch stays * around until our own memory allocation is released */ drm_dp_mst_get_mstb_malloc(mstb); return port; } static int drm_dp_mst_handle_link_address_port(struct drm_dp_mst_branch *mstb, struct drm_device *dev, struct drm_dp_link_addr_reply_port *port_msg) { struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; struct drm_dp_mst_port *port; int old_ddps = 0, ret; u8 new_pdt = DP_PEER_DEVICE_NONE; bool new_mcs = 0; bool created = false, send_link_addr = false, changed = false; port = drm_dp_get_port(mstb, port_msg->port_number); if (!port) { port = drm_dp_mst_add_port(dev, mgr, mstb, port_msg->port_number); if (!port) return -ENOMEM; created = true; changed = true; } else if (!port->input && port_msg->input_port && port->connector) { /* Since port->connector can't be changed here, we create a * new port if input_port changes from 0 to 1 */ drm_dp_mst_topology_unlink_port(mgr, port); drm_dp_mst_topology_put_port(port); port = drm_dp_mst_add_port(dev, mgr, mstb, port_msg->port_number); if (!port) return -ENOMEM; changed = true; created = true; } else if (port->input && !port_msg->input_port) { changed = true; } else if (port->connector) { /* We're updating a port that's exposed to userspace, so do it * under lock */ drm_modeset_lock(&mgr->base.lock, NULL); old_ddps = port->ddps; changed = port->ddps != port_msg->ddps || (port->ddps && (port->ldps != port_msg->legacy_device_plug_status || port->dpcd_rev != port_msg->dpcd_revision || port->mcs != port_msg->mcs || port->pdt != port_msg->peer_device_type || port->num_sdp_stream_sinks != port_msg->num_sdp_stream_sinks)); } port->input = port_msg->input_port; if (!port->input) new_pdt = port_msg->peer_device_type; new_mcs = port_msg->mcs; port->ddps = port_msg->ddps; port->ldps = port_msg->legacy_device_plug_status; port->dpcd_rev = port_msg->dpcd_revision; port->num_sdp_streams = port_msg->num_sdp_streams; port->num_sdp_stream_sinks = port_msg->num_sdp_stream_sinks; /* manage mstb port lists with mgr lock - take a reference for this list */ if (created) { mutex_lock(&mgr->lock); drm_dp_mst_topology_get_port(port); list_add(&port->next, &mstb->ports); mstb->num_ports++; mutex_unlock(&mgr->lock); } /* * Reprobe PBN caps on both hotplug, and when re-probing the link * for our parent mstb */ if (old_ddps != port->ddps || !created) { if (port->ddps && !port->input) { ret = drm_dp_send_enum_path_resources(mgr, mstb, port); if (ret == 1) changed = true; } else { port->full_pbn = 0; } } ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs); if (ret == 1) { send_link_addr = true; } else if (ret < 0) { drm_err(dev, "Failed to change PDT on port %p: %d\n", port, ret); goto fail; } /* * If this port wasn't just created, then we're reprobing because * we're coming out of suspend. In this case, always resend the link * address if there's an MSTB on this port */ if (!created && port->pdt == DP_PEER_DEVICE_MST_BRANCHING && port->mcs) send_link_addr = true; if (port->connector) drm_modeset_unlock(&mgr->base.lock); else if (!port->input) drm_dp_mst_port_add_connector(mstb, port); if (send_link_addr && port->mstb) { ret = drm_dp_send_link_address(mgr, port->mstb); if (ret == 1) /* MSTB below us changed */ changed = true; else if (ret < 0) goto fail_put; } /* put reference to this port */ drm_dp_mst_topology_put_port(port); return changed; fail: drm_dp_mst_topology_unlink_port(mgr, port); if (port->connector) drm_modeset_unlock(&mgr->base.lock); fail_put: drm_dp_mst_topology_put_port(port); return ret; } static int drm_dp_mst_handle_conn_stat(struct drm_dp_mst_branch *mstb, struct drm_dp_connection_status_notify *conn_stat) { struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; struct drm_dp_mst_port *port; int old_ddps, ret; u8 new_pdt; bool new_mcs; bool dowork = false, create_connector = false; port = drm_dp_get_port(mstb, conn_stat->port_number); if (!port) return 0; if (port->connector) { if (!port->input && conn_stat->input_port) { /* * We can't remove a connector from an already exposed * port, so just throw the port out and make sure we * reprobe the link address of it's parent MSTB */ drm_dp_mst_topology_unlink_port(mgr, port); mstb->link_address_sent = false; dowork = true; goto out; } /* Locking is only needed if the port's exposed to userspace */ drm_modeset_lock(&mgr->base.lock, NULL); } else if (port->input && !conn_stat->input_port) { create_connector = true; /* Reprobe link address so we get num_sdp_streams */ mstb->link_address_sent = false; dowork = true; } old_ddps = port->ddps; port->input = conn_stat->input_port; port->ldps = conn_stat->legacy_device_plug_status; port->ddps = conn_stat->displayport_device_plug_status; if (old_ddps != port->ddps) { if (port->ddps && !port->input) drm_dp_send_enum_path_resources(mgr, mstb, port); else port->full_pbn = 0; } new_pdt = port->input ? DP_PEER_DEVICE_NONE : conn_stat->peer_device_type; new_mcs = conn_stat->message_capability_status; ret = drm_dp_port_set_pdt(port, new_pdt, new_mcs); if (ret == 1) { dowork = true; } else if (ret < 0) { drm_err(mgr->dev, "Failed to change PDT for port %p: %d\n", port, ret); dowork = false; } if (port->connector) drm_modeset_unlock(&mgr->base.lock); else if (create_connector) drm_dp_mst_port_add_connector(mstb, port); out: drm_dp_mst_topology_put_port(port); return dowork; } static struct drm_dp_mst_branch *drm_dp_get_mst_branch_device(struct drm_dp_mst_topology_mgr *mgr, u8 lct, u8 *rad) { struct drm_dp_mst_branch *mstb; struct drm_dp_mst_port *port; int i, ret; /* find the port by iterating down */ mutex_lock(&mgr->lock); mstb = mgr->mst_primary; if (!mstb) goto out; for (i = 0; i < lct - 1; i++) { int shift = (i % 2) ? 0 : 4; int port_num = (rad[i / 2] >> shift) & 0xf; list_for_each_entry(port, &mstb->ports, next) { if (port->port_num == port_num) { mstb = port->mstb; if (!mstb) { drm_err(mgr->dev, "failed to lookup MSTB with lct %d, rad %02x\n", lct, rad[0]); goto out; } break; } } } ret = drm_dp_mst_topology_try_get_mstb(mstb); if (!ret) mstb = NULL; out: mutex_unlock(&mgr->lock); return mstb; } static struct drm_dp_mst_branch *get_mst_branch_device_by_guid_helper( struct drm_dp_mst_branch *mstb, const uint8_t *guid) { struct drm_dp_mst_branch *found_mstb; struct drm_dp_mst_port *port; if (!mstb) return NULL; if (memcmp(mstb->guid, guid, 16) == 0) return mstb; list_for_each_entry(port, &mstb->ports, next) { found_mstb = get_mst_branch_device_by_guid_helper(port->mstb, guid); if (found_mstb) return found_mstb; } return NULL; } static struct drm_dp_mst_branch * drm_dp_get_mst_branch_device_by_guid(struct drm_dp_mst_topology_mgr *mgr, const uint8_t *guid) { struct drm_dp_mst_branch *mstb; int ret; /* find the port by iterating down */ mutex_lock(&mgr->lock); mstb = get_mst_branch_device_by_guid_helper(mgr->mst_primary, guid); if (mstb) { ret = drm_dp_mst_topology_try_get_mstb(mstb); if (!ret) mstb = NULL; } mutex_unlock(&mgr->lock); return mstb; } static int drm_dp_check_and_send_link_address(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) { struct drm_dp_mst_port *port; int ret; bool changed = false; if (!mstb->link_address_sent) { ret = drm_dp_send_link_address(mgr, mstb); if (ret == 1) changed = true; else if (ret < 0) return ret; } list_for_each_entry(port, &mstb->ports, next) { if (port->input || !port->ddps || !port->mstb) continue; ret = drm_dp_check_and_send_link_address(mgr, port->mstb); if (ret == 1) changed = true; else if (ret < 0) return ret; } return changed; } static void drm_dp_mst_link_probe_work(struct work_struct *work) { struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, work); struct drm_device *dev = mgr->dev; struct drm_dp_mst_branch *mstb; int ret; bool clear_payload_id_table; mutex_lock(&mgr->probe_lock); mutex_lock(&mgr->lock); clear_payload_id_table = !mgr->payload_id_table_cleared; mgr->payload_id_table_cleared = true; mstb = mgr->mst_primary; if (mstb) { ret = drm_dp_mst_topology_try_get_mstb(mstb); if (!ret) mstb = NULL; } mutex_unlock(&mgr->lock); if (!mstb) { mutex_unlock(&mgr->probe_lock); return; } /* * Certain branch devices seem to incorrectly report an available_pbn * of 0 on downstream sinks, even after clearing the * DP_PAYLOAD_ALLOCATE_* registers in * drm_dp_mst_topology_mgr_set_mst(). Namely, the CableMatters USB-C * 2x DP hub. Sending a CLEAR_PAYLOAD_ID_TABLE message seems to make * things work again. */ if (clear_payload_id_table) { drm_dbg_kms(dev, "Clearing payload ID table\n"); drm_dp_send_clear_payload_id_table(mgr, mstb); } ret = drm_dp_check_and_send_link_address(mgr, mstb); drm_dp_mst_topology_put_mstb(mstb); mutex_unlock(&mgr->probe_lock); if (ret > 0) drm_kms_helper_hotplug_event(dev); } static bool drm_dp_validate_guid(struct drm_dp_mst_topology_mgr *mgr, u8 *guid) { u64 salt; if (memchr_inv(guid, 0, 16)) return true; salt = get_jiffies_64(); memcpy(&guid[0], &salt, sizeof(u64)); memcpy(&guid[8], &salt, sizeof(u64)); return false; } static void build_dpcd_read(struct drm_dp_sideband_msg_tx *msg, u8 port_num, u32 offset, u8 num_bytes) { struct drm_dp_sideband_msg_req_body req; req.req_type = DP_REMOTE_DPCD_READ; req.u.dpcd_read.port_number = port_num; req.u.dpcd_read.dpcd_address = offset; req.u.dpcd_read.num_bytes = num_bytes; drm_dp_encode_sideband_req(&req, msg); } static int drm_dp_send_sideband_msg(struct drm_dp_mst_topology_mgr *mgr, bool up, u8 *msg, int len) { int ret; int regbase = up ? DP_SIDEBAND_MSG_UP_REP_BASE : DP_SIDEBAND_MSG_DOWN_REQ_BASE; int tosend, total, offset; int retries = 0; retry: total = len; offset = 0; do { tosend = min3(mgr->max_dpcd_transaction_bytes, 16, total); ret = drm_dp_dpcd_write(mgr->aux, regbase + offset, &msg[offset], tosend); if (ret != tosend) { if (ret == -EIO && retries < 5) { retries++; goto retry; } drm_dbg_kms(mgr->dev, "failed to dpcd write %d %d\n", tosend, ret); return -EIO; } offset += tosend; total -= tosend; } while (total > 0); return 0; } static int set_hdr_from_dst_qlock(struct drm_dp_sideband_msg_hdr *hdr, struct drm_dp_sideband_msg_tx *txmsg) { struct drm_dp_mst_branch *mstb = txmsg->dst; u8 req_type; req_type = txmsg->msg[0] & 0x7f; if (req_type == DP_CONNECTION_STATUS_NOTIFY || req_type == DP_RESOURCE_STATUS_NOTIFY || req_type == DP_CLEAR_PAYLOAD_ID_TABLE) hdr->broadcast = 1; else hdr->broadcast = 0; hdr->path_msg = txmsg->path_msg; if (hdr->broadcast) { hdr->lct = 1; hdr->lcr = 6; } else { hdr->lct = mstb->lct; hdr->lcr = mstb->lct - 1; } memcpy(hdr->rad, mstb->rad, hdr->lct / 2); return 0; } /* * process a single block of the next message in the sideband queue */ static int process_single_tx_qlock(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_tx *txmsg, bool up) { u8 chunk[48]; struct drm_dp_sideband_msg_hdr hdr; int len, space, idx, tosend; int ret; if (txmsg->state == DRM_DP_SIDEBAND_TX_SENT) return 0; memset(&hdr, 0, sizeof(struct drm_dp_sideband_msg_hdr)); if (txmsg->state == DRM_DP_SIDEBAND_TX_QUEUED) txmsg->state = DRM_DP_SIDEBAND_TX_START_SEND; /* make hdr from dst mst */ ret = set_hdr_from_dst_qlock(&hdr, txmsg); if (ret < 0) return ret; /* amount left to send in this message */ len = txmsg->cur_len - txmsg->cur_offset; /* 48 - sideband msg size - 1 byte for data CRC, x header bytes */ space = 48 - 1 - drm_dp_calc_sb_hdr_size(&hdr); tosend = min(len, space); if (len == txmsg->cur_len) hdr.somt = 1; if (space >= len) hdr.eomt = 1; hdr.msg_len = tosend + 1; drm_dp_encode_sideband_msg_hdr(&hdr, chunk, &idx); memcpy(&chunk[idx], &txmsg->msg[txmsg->cur_offset], tosend); /* add crc at end */ drm_dp_crc_sideband_chunk_req(&chunk[idx], tosend); idx += tosend + 1; ret = drm_dp_send_sideband_msg(mgr, up, chunk, idx); if (ret) { if (drm_debug_enabled(DRM_UT_DP)) { struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP, DBG_PREFIX); drm_printf(&p, "sideband msg failed to send\n"); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); } return ret; } txmsg->cur_offset += tosend; if (txmsg->cur_offset == txmsg->cur_len) { txmsg->state = DRM_DP_SIDEBAND_TX_SENT; return 1; } return 0; } static void process_single_down_tx_qlock(struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_sideband_msg_tx *txmsg; int ret; WARN_ON(!mutex_is_locked(&mgr->qlock)); /* construct a chunk from the first msg in the tx_msg queue */ if (list_empty(&mgr->tx_msg_downq)) return; txmsg = list_first_entry(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); ret = process_single_tx_qlock(mgr, txmsg, false); if (ret < 0) { drm_dbg_kms(mgr->dev, "failed to send msg in q %d\n", ret); list_del(&txmsg->next); txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; wake_up_all(&mgr->tx_waitq); } } static void drm_dp_queue_down_tx(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_sideband_msg_tx *txmsg) { mutex_lock(&mgr->qlock); list_add_tail(&txmsg->next, &mgr->tx_msg_downq); if (drm_debug_enabled(DRM_UT_DP)) { struct drm_printer p = drm_dbg_printer(mgr->dev, DRM_UT_DP, DBG_PREFIX); drm_dp_mst_dump_sideband_msg_tx(&p, txmsg); } if (list_is_singular(&mgr->tx_msg_downq)) process_single_down_tx_qlock(mgr); mutex_unlock(&mgr->qlock); } static void drm_dp_dump_link_address(const struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_link_address_ack_reply *reply) { struct drm_dp_link_addr_reply_port *port_reply; int i; for (i = 0; i < reply->nports; i++) { port_reply = &reply->ports[i]; drm_dbg_kms(mgr->dev, "port %d: input %d, pdt: %d, pn: %d, dpcd_rev: %02x, mcs: %d, ddps: %d, ldps %d, sdp %d/%d\n", i, port_reply->input_port, port_reply->peer_device_type, port_reply->port_number, port_reply->dpcd_revision, port_reply->mcs, port_reply->ddps, port_reply->legacy_device_plug_status, port_reply->num_sdp_streams, port_reply->num_sdp_stream_sinks); } } static int drm_dp_send_link_address(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) { struct drm_dp_sideband_msg_tx *txmsg; struct drm_dp_link_address_ack_reply *reply; struct drm_dp_mst_port *port, *tmp; int i, ret, port_mask = 0; bool changed = false; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) return -ENOMEM; txmsg->dst = mstb; build_link_address(txmsg); mstb->link_address_sent = true; drm_dp_queue_down_tx(mgr, txmsg); /* FIXME: Actually do some real error handling here */ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret < 0) { drm_err(mgr->dev, "Sending link address failed with %d\n", ret); goto out; } if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { drm_err(mgr->dev, "link address NAK received\n"); ret = -EIO; goto out; } reply = &txmsg->reply.u.link_addr; drm_dbg_kms(mgr->dev, "link address reply: %d\n", reply->nports); drm_dp_dump_link_address(mgr, reply); ret = drm_dp_check_mstb_guid(mstb, reply->guid); if (ret) { char buf[64]; drm_dp_mst_rad_to_str(mstb->rad, mstb->lct, buf, sizeof(buf)); drm_err(mgr->dev, "GUID check on %s failed: %d\n", buf, ret); goto out; } for (i = 0; i < reply->nports; i++) { port_mask |= BIT(reply->ports[i].port_number); ret = drm_dp_mst_handle_link_address_port(mstb, mgr->dev, &reply->ports[i]); if (ret == 1) changed = true; else if (ret < 0) goto out; } /* Prune any ports that are currently a part of mstb in our in-memory * topology, but were not seen in this link address. Usually this * means that they were removed while the topology was out of sync, * e.g. during suspend/resume */ mutex_lock(&mgr->lock); list_for_each_entry_safe(port, tmp, &mstb->ports, next) { if (port_mask & BIT(port->port_num)) continue; drm_dbg_kms(mgr->dev, "port %d was not in link address, removing\n", port->port_num); list_del(&port->next); drm_dp_mst_topology_put_port(port); changed = true; } mutex_unlock(&mgr->lock); out: if (ret < 0) mstb->link_address_sent = false; kfree(txmsg); return ret < 0 ? ret : changed; } static void drm_dp_send_clear_payload_id_table(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb) { struct drm_dp_sideband_msg_tx *txmsg; int ret; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) return; txmsg->dst = mstb; build_clear_payload_id_table(txmsg); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0 && txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) drm_dbg_kms(mgr->dev, "clear payload table id nak received\n"); kfree(txmsg); } static int drm_dp_send_enum_path_resources(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *port) { struct drm_dp_enum_path_resources_ack_reply *path_res; struct drm_dp_sideband_msg_tx *txmsg; int ret; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) return -ENOMEM; txmsg->dst = mstb; build_enum_path_resources(txmsg, port->port_num); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0) { ret = 0; path_res = &txmsg->reply.u.path_resources; if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { drm_dbg_kms(mgr->dev, "enum path resources nak received\n"); } else { if (port->port_num != path_res->port_number) DRM_ERROR("got incorrect port in response\n"); drm_dbg_kms(mgr->dev, "enum path resources %d: %d %d\n", path_res->port_number, path_res->full_payload_bw_number, path_res->avail_payload_bw_number); /* * If something changed, make sure we send a * hotplug */ if (port->full_pbn != path_res->full_payload_bw_number || port->fec_capable != path_res->fec_capable) ret = 1; port->full_pbn = path_res->full_payload_bw_number; port->fec_capable = path_res->fec_capable; } } kfree(txmsg); return ret; } static struct drm_dp_mst_port *drm_dp_get_last_connected_port_to_mstb(struct drm_dp_mst_branch *mstb) { if (!mstb->port_parent) return NULL; if (mstb->port_parent->mstb != mstb) return mstb->port_parent; return drm_dp_get_last_connected_port_to_mstb(mstb->port_parent->parent); } /* * Searches upwards in the topology starting from mstb to try to find the * closest available parent of mstb that's still connected to the rest of the * topology. This can be used in order to perform operations like releasing * payloads, where the branch device which owned the payload may no longer be * around and thus would require that the payload on the last living relative * be freed instead. */ static struct drm_dp_mst_branch * drm_dp_get_last_connected_port_and_mstb(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb, int *port_num) { struct drm_dp_mst_branch *rmstb = NULL; struct drm_dp_mst_port *found_port; mutex_lock(&mgr->lock); if (!mgr->mst_primary) goto out; do { found_port = drm_dp_get_last_connected_port_to_mstb(mstb); if (!found_port) break; if (drm_dp_mst_topology_try_get_mstb(found_port->parent)) { rmstb = found_port->parent; *port_num = found_port->port_num; } else { /* Search again, starting from this parent */ mstb = found_port->parent; } } while (!rmstb); out: mutex_unlock(&mgr->lock); return rmstb; } static int drm_dp_payload_send_msg(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int id, int pbn) { struct drm_dp_sideband_msg_tx *txmsg; struct drm_dp_mst_branch *mstb; int ret, port_num; u8 sinks[DRM_DP_MAX_SDP_STREAMS]; int i; port_num = port->port_num; mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); if (!mstb) { mstb = drm_dp_get_last_connected_port_and_mstb(mgr, port->parent, &port_num); if (!mstb) return -EINVAL; } txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { ret = -ENOMEM; goto fail_put; } for (i = 0; i < port->num_sdp_streams; i++) sinks[i] = i; txmsg->dst = mstb; build_allocate_payload(txmsg, port_num, id, pbn, port->num_sdp_streams, sinks); drm_dp_queue_down_tx(mgr, txmsg); /* * FIXME: there is a small chance that between getting the last * connected mstb and sending the payload message, the last connected * mstb could also be removed from the topology. In the future, this * needs to be fixed by restarting the * drm_dp_get_last_connected_port_and_mstb() search in the event of a * timeout if the topology is still connected to the system. */ ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0) { if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) ret = -EINVAL; else ret = 0; } kfree(txmsg); fail_put: drm_dp_mst_topology_put_mstb(mstb); return ret; } int drm_dp_send_power_updown_phy(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, bool power_up) { struct drm_dp_sideband_msg_tx *txmsg; int ret; port = drm_dp_mst_topology_get_port_validated(mgr, port); if (!port) return -EINVAL; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { drm_dp_mst_topology_put_port(port); return -ENOMEM; } txmsg->dst = port->parent; build_power_updown_phy(txmsg, port->port_num, power_up); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(port->parent, txmsg); if (ret > 0) { if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) ret = -EINVAL; else ret = 0; } kfree(txmsg); drm_dp_mst_topology_put_port(port); return ret; } EXPORT_SYMBOL(drm_dp_send_power_updown_phy); int drm_dp_send_query_stream_enc_status(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, struct drm_dp_query_stream_enc_status_ack_reply *status) { struct drm_dp_mst_topology_state *state; struct drm_dp_mst_atomic_payload *payload; struct drm_dp_sideband_msg_tx *txmsg; u8 nonce[7]; int ret; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) return -ENOMEM; port = drm_dp_mst_topology_get_port_validated(mgr, port); if (!port) { ret = -EINVAL; goto out_get_port; } get_random_bytes(nonce, sizeof(nonce)); drm_modeset_lock(&mgr->base.lock, NULL); state = to_drm_dp_mst_topology_state(mgr->base.state); payload = drm_atomic_get_mst_payload_state(state, port); /* * "Source device targets the QUERY_STREAM_ENCRYPTION_STATUS message * transaction at the MST Branch device directly connected to the * Source" */ txmsg->dst = mgr->mst_primary; build_query_stream_enc_status(txmsg, payload->vcpi, nonce); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mgr->mst_primary, txmsg); if (ret < 0) { goto out; } else if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { drm_dbg_kms(mgr->dev, "query encryption status nak received\n"); ret = -ENXIO; goto out; } ret = 0; memcpy(status, &txmsg->reply.u.enc_status, sizeof(*status)); out: drm_modeset_unlock(&mgr->base.lock); drm_dp_mst_topology_put_port(port); out_get_port: kfree(txmsg); return ret; } EXPORT_SYMBOL(drm_dp_send_query_stream_enc_status); static int drm_dp_create_payload_at_dfp(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_atomic_payload *payload) { return drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, payload->time_slots); } static int drm_dp_create_payload_to_remote(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_atomic_payload *payload) { int ret; struct drm_dp_mst_port *port = drm_dp_mst_topology_get_port_validated(mgr, payload->port); if (!port) return -EIO; ret = drm_dp_payload_send_msg(mgr, port, payload->vcpi, payload->pbn); drm_dp_mst_topology_put_port(port); return ret; } static void drm_dp_destroy_payload_at_remote_and_dfp(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state, struct drm_dp_mst_atomic_payload *payload) { drm_dbg_kms(mgr->dev, "\n"); /* it's okay for these to fail */ if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_REMOTE) { drm_dp_payload_send_msg(mgr, payload->port, payload->vcpi, 0); payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_DFP; } if (payload->payload_allocation_status == DRM_DP_MST_PAYLOAD_ALLOCATION_DFP) drm_dp_dpcd_write_payload(mgr, payload->vcpi, payload->vc_start_slot, 0); } /** * drm_dp_add_payload_part1() - Execute payload update part 1 * @mgr: Manager to use. * @mst_state: The MST atomic state * @payload: The payload to write * * Determines the starting time slot for the given payload, and programs the VCPI for this payload * into the DPCD of DPRX. After calling this, the driver should generate ACT and payload packets. * * Returns: 0 on success, error code on failure. */ int drm_dp_add_payload_part1(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state, struct drm_dp_mst_atomic_payload *payload) { struct drm_dp_mst_port *port; int ret; /* Update mst mgr info */ if (mgr->payload_count == 0) mgr->next_start_slot = mst_state->start_slot; payload->vc_start_slot = mgr->next_start_slot; mgr->payload_count++; mgr->next_start_slot += payload->time_slots; payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_LOCAL; /* Allocate payload to immediate downstream facing port */ port = drm_dp_mst_topology_get_port_validated(mgr, payload->port); if (!port) { drm_dbg_kms(mgr->dev, "VCPI %d for port %p not in topology, not creating a payload to remote\n", payload->vcpi, payload->port); return -EIO; } ret = drm_dp_create_payload_at_dfp(mgr, payload); if (ret < 0) { drm_dbg_kms(mgr->dev, "Failed to create MST payload for port %p: %d\n", payload->port, ret); goto put_port; } payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_DFP; put_port: drm_dp_mst_topology_put_port(port); return ret; } EXPORT_SYMBOL(drm_dp_add_payload_part1); /** * drm_dp_remove_payload_part1() - Remove an MST payload along the virtual channel * @mgr: Manager to use. * @mst_state: The MST atomic state * @payload: The payload to remove * * Removes a payload along the virtual channel if it was successfully allocated. * After calling this, the driver should set HW to generate ACT and then switch to new * payload allocation state. */ void drm_dp_remove_payload_part1(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state, struct drm_dp_mst_atomic_payload *payload) { /* Remove remote payload allocation */ bool send_remove = false; mutex_lock(&mgr->lock); send_remove = drm_dp_mst_port_downstream_of_branch(payload->port, mgr->mst_primary); mutex_unlock(&mgr->lock); if (send_remove) drm_dp_destroy_payload_at_remote_and_dfp(mgr, mst_state, payload); else drm_dbg_kms(mgr->dev, "Payload for VCPI %d not in topology, not sending remove\n", payload->vcpi); payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_LOCAL; } EXPORT_SYMBOL(drm_dp_remove_payload_part1); /** * drm_dp_remove_payload_part2() - Remove an MST payload locally * @mgr: Manager to use. * @mst_state: The MST atomic state * @old_payload: The payload with its old state * @new_payload: The payload with its latest state * * Updates the starting time slots of all other payloads which would have been shifted towards * the start of the payload ID table as a result of removing a payload. Driver should call this * function whenever it removes a payload in its HW. It's independent to the result of payload * allocation/deallocation at branch devices along the virtual channel. */ void drm_dp_remove_payload_part2(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state, const struct drm_dp_mst_atomic_payload *old_payload, struct drm_dp_mst_atomic_payload *new_payload) { struct drm_dp_mst_atomic_payload *pos; /* Remove local payload allocation */ list_for_each_entry(pos, &mst_state->payloads, next) { if (pos != new_payload && pos->vc_start_slot > new_payload->vc_start_slot) pos->vc_start_slot -= old_payload->time_slots; } new_payload->vc_start_slot = -1; mgr->payload_count--; mgr->next_start_slot -= old_payload->time_slots; if (new_payload->delete) drm_dp_mst_put_port_malloc(new_payload->port); new_payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_NONE; } EXPORT_SYMBOL(drm_dp_remove_payload_part2); /** * drm_dp_add_payload_part2() - Execute payload update part 2 * @mgr: Manager to use. * @payload: The payload to update * * If @payload was successfully assigned a starting time slot by drm_dp_add_payload_part1(), this * function will send the sideband messages to finish allocating this payload. * * Returns: 0 on success, negative error code on failure. */ int drm_dp_add_payload_part2(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_atomic_payload *payload) { int ret = 0; /* Skip failed payloads */ if (payload->payload_allocation_status != DRM_DP_MST_PAYLOAD_ALLOCATION_DFP) { drm_dbg_kms(mgr->dev, "Part 1 of payload creation for %s failed, skipping part 2\n", payload->port->connector->name); return -EIO; } /* Allocate payload to remote end */ ret = drm_dp_create_payload_to_remote(mgr, payload); if (ret < 0) drm_err(mgr->dev, "Step 2 of creating MST payload for %p failed: %d\n", payload->port, ret); else payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_REMOTE; return ret; } EXPORT_SYMBOL(drm_dp_add_payload_part2); static int drm_dp_send_dpcd_read(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int offset, int size, u8 *bytes) { int ret = 0; struct drm_dp_sideband_msg_tx *txmsg; struct drm_dp_mst_branch *mstb; mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); if (!mstb) return -EINVAL; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { ret = -ENOMEM; goto fail_put; } build_dpcd_read(txmsg, port->port_num, offset, size); txmsg->dst = port->parent; drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret < 0) goto fail_free; if (txmsg->reply.reply_type == 1) { drm_dbg_kms(mgr->dev, "mstb %p port %d: DPCD read on addr 0x%x for %d bytes NAKed\n", mstb, port->port_num, offset, size); ret = -EIO; goto fail_free; } if (txmsg->reply.u.remote_dpcd_read_ack.num_bytes != size) { ret = -EPROTO; goto fail_free; } ret = min_t(size_t, txmsg->reply.u.remote_dpcd_read_ack.num_bytes, size); memcpy(bytes, txmsg->reply.u.remote_dpcd_read_ack.bytes, ret); fail_free: kfree(txmsg); fail_put: drm_dp_mst_topology_put_mstb(mstb); return ret; } static int drm_dp_send_dpcd_write(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int offset, int size, u8 *bytes) { int ret; struct drm_dp_sideband_msg_tx *txmsg; struct drm_dp_mst_branch *mstb; mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); if (!mstb) return -EINVAL; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { ret = -ENOMEM; goto fail_put; } build_dpcd_write(txmsg, port->port_num, offset, size, bytes); txmsg->dst = mstb; drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0) { if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) ret = -EIO; else ret = size; } kfree(txmsg); fail_put: drm_dp_mst_topology_put_mstb(mstb); return ret; } static int drm_dp_encode_up_ack_reply(struct drm_dp_sideband_msg_tx *msg, u8 req_type) { struct drm_dp_sideband_msg_reply_body reply; reply.reply_type = DP_SIDEBAND_REPLY_ACK; reply.req_type = req_type; drm_dp_encode_sideband_reply(&reply, msg); return 0; } static int drm_dp_send_up_ack_reply(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_branch *mstb, int req_type, bool broadcast) { struct drm_dp_sideband_msg_tx *txmsg; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) return -ENOMEM; txmsg->dst = mstb; drm_dp_encode_up_ack_reply(txmsg, req_type); mutex_lock(&mgr->qlock); /* construct a chunk from the first msg in the tx_msg queue */ process_single_tx_qlock(mgr, txmsg, true); mutex_unlock(&mgr->qlock); kfree(txmsg); return 0; } /** * drm_dp_get_vc_payload_bw - get the VC payload BW for an MST link * @mgr: The &drm_dp_mst_topology_mgr to use * @link_rate: link rate in 10kbits/s units * @link_lane_count: lane count * * Calculate the total bandwidth of a MultiStream Transport link. The returned * value is in units of PBNs/(timeslots/1 MTP). This value can be used to * convert the number of PBNs required for a given stream to the number of * timeslots this stream requires in each MTP. * * Returns the BW / timeslot value in 20.12 fixed point format. */ fixed20_12 drm_dp_get_vc_payload_bw(const struct drm_dp_mst_topology_mgr *mgr, int link_rate, int link_lane_count) { int ch_coding_efficiency = drm_dp_bw_channel_coding_efficiency(drm_dp_is_uhbr_rate(link_rate)); fixed20_12 ret; if (link_rate == 0 || link_lane_count == 0) drm_dbg_kms(mgr->dev, "invalid link rate/lane count: (%d / %d)\n", link_rate, link_lane_count); /* See DP v2.0 2.6.4.2, 2.7.6.3 VCPayload_Bandwidth_for_OneTimeSlotPer_MTP_Allocation */ ret.full = DIV_ROUND_DOWN_ULL(mul_u32_u32(link_rate * link_lane_count, ch_coding_efficiency), (1000000ULL * 8 * 5400) >> 12); return ret; } EXPORT_SYMBOL(drm_dp_get_vc_payload_bw); /** * drm_dp_read_mst_cap() - Read the sink's MST mode capability * @aux: The DP AUX channel to use * @dpcd: A cached copy of the DPCD capabilities for this sink * * Returns: enum drm_dp_mst_mode to indicate MST mode capability */ enum drm_dp_mst_mode drm_dp_read_mst_cap(struct drm_dp_aux *aux, const u8 dpcd[DP_RECEIVER_CAP_SIZE]) { u8 mstm_cap; if (dpcd[DP_DPCD_REV] < DP_DPCD_REV_12) return DRM_DP_SST; if (drm_dp_dpcd_readb(aux, DP_MSTM_CAP, &mstm_cap) != 1) return DRM_DP_SST; if (mstm_cap & DP_MST_CAP) return DRM_DP_MST; if (mstm_cap & DP_SINGLE_STREAM_SIDEBAND_MSG) return DRM_DP_SST_SIDEBAND_MSG; return DRM_DP_SST; } EXPORT_SYMBOL(drm_dp_read_mst_cap); /** * drm_dp_mst_topology_mgr_set_mst() - Set the MST state for a topology manager * @mgr: manager to set state for * @mst_state: true to enable MST on this connector - false to disable. * * This is called by the driver when it detects an MST capable device plugged * into a DP MST capable port, or when a DP MST capable device is unplugged. */ int drm_dp_mst_topology_mgr_set_mst(struct drm_dp_mst_topology_mgr *mgr, bool mst_state) { int ret = 0; struct drm_dp_mst_branch *mstb = NULL; mutex_lock(&mgr->lock); if (mst_state == mgr->mst_state) goto out_unlock; mgr->mst_state = mst_state; /* set the device into MST mode */ if (mst_state) { WARN_ON(mgr->mst_primary); /* get dpcd info */ ret = drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd); if (ret < 0) { drm_dbg_kms(mgr->dev, "%s: failed to read DPCD, ret %d\n", mgr->aux->name, ret); goto out_unlock; } /* add initial branch device at LCT 1 */ mstb = drm_dp_add_mst_branch_device(1, NULL); if (mstb == NULL) { ret = -ENOMEM; goto out_unlock; } mstb->mgr = mgr; /* give this the main reference */ mgr->mst_primary = mstb; drm_dp_mst_topology_get_mstb(mgr->mst_primary); ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); if (ret < 0) goto out_unlock; /* Write reset payload */ drm_dp_dpcd_write_payload(mgr, 0, 0, 0x3f); queue_work(system_long_wq, &mgr->work); ret = 0; } else { /* disable MST on the device */ mstb = mgr->mst_primary; mgr->mst_primary = NULL; /* this can fail if the device is gone */ drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, 0); ret = 0; mgr->payload_id_table_cleared = false; memset(&mgr->down_rep_recv, 0, sizeof(mgr->down_rep_recv)); memset(&mgr->up_req_recv, 0, sizeof(mgr->up_req_recv)); } out_unlock: mutex_unlock(&mgr->lock); if (mstb) drm_dp_mst_topology_put_mstb(mstb); return ret; } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_set_mst); static void drm_dp_mst_topology_mgr_invalidate_mstb(struct drm_dp_mst_branch *mstb) { struct drm_dp_mst_port *port; /* The link address will need to be re-sent on resume */ mstb->link_address_sent = false; list_for_each_entry(port, &mstb->ports, next) if (port->mstb) drm_dp_mst_topology_mgr_invalidate_mstb(port->mstb); } /** * drm_dp_mst_topology_mgr_suspend() - suspend the MST manager * @mgr: manager to suspend * * This function tells the MST device that we can't handle UP messages * anymore. This should stop it from sending any since we are suspended. */ void drm_dp_mst_topology_mgr_suspend(struct drm_dp_mst_topology_mgr *mgr) { mutex_lock(&mgr->lock); drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, DP_MST_EN | DP_UPSTREAM_IS_SRC); mutex_unlock(&mgr->lock); flush_work(&mgr->up_req_work); flush_work(&mgr->work); flush_work(&mgr->delayed_destroy_work); mutex_lock(&mgr->lock); if (mgr->mst_state && mgr->mst_primary) drm_dp_mst_topology_mgr_invalidate_mstb(mgr->mst_primary); mutex_unlock(&mgr->lock); } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_suspend); /** * drm_dp_mst_topology_mgr_resume() - resume the MST manager * @mgr: manager to resume * @sync: whether or not to perform topology reprobing synchronously * * This will fetch DPCD and see if the device is still there, * if it is, it will rewrite the MSTM control bits, and return. * * If the device fails this returns -1, and the driver should do * a full MST reprobe, in case we were undocked. * * During system resume (where it is assumed that the driver will be calling * drm_atomic_helper_resume()) this function should be called beforehand with * @sync set to true. In contexts like runtime resume where the driver is not * expected to be calling drm_atomic_helper_resume(), this function should be * called with @sync set to false in order to avoid deadlocking. * * Returns: -1 if the MST topology was removed while we were suspended, 0 * otherwise. */ int drm_dp_mst_topology_mgr_resume(struct drm_dp_mst_topology_mgr *mgr, bool sync) { int ret; u8 guid[16]; mutex_lock(&mgr->lock); if (!mgr->mst_primary) goto out_fail; if (drm_dp_read_dpcd_caps(mgr->aux, mgr->dpcd) < 0) { drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n"); goto out_fail; } ret = drm_dp_dpcd_writeb(mgr->aux, DP_MSTM_CTRL, DP_MST_EN | DP_UP_REQ_EN | DP_UPSTREAM_IS_SRC); if (ret < 0) { drm_dbg_kms(mgr->dev, "mst write failed - undocked during suspend?\n"); goto out_fail; } /* Some hubs forget their guids after they resume */ ret = drm_dp_dpcd_read(mgr->aux, DP_GUID, guid, 16); if (ret != 16) { drm_dbg_kms(mgr->dev, "dpcd read failed - undocked during suspend?\n"); goto out_fail; } ret = drm_dp_check_mstb_guid(mgr->mst_primary, guid); if (ret) { drm_dbg_kms(mgr->dev, "check mstb failed - undocked during suspend?\n"); goto out_fail; } /* * For the final step of resuming the topology, we need to bring the * state of our in-memory topology back into sync with reality. So, * restart the probing process as if we're probing a new hub */ queue_work(system_long_wq, &mgr->work); mutex_unlock(&mgr->lock); if (sync) { drm_dbg_kms(mgr->dev, "Waiting for link probe work to finish re-syncing topology...\n"); flush_work(&mgr->work); } return 0; out_fail: mutex_unlock(&mgr->lock); return -1; } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_resume); static bool drm_dp_get_one_sb_msg(struct drm_dp_mst_topology_mgr *mgr, bool up, struct drm_dp_mst_branch **mstb) { int len; u8 replyblock[32]; int replylen, curreply; int ret; u8 hdrlen; struct drm_dp_sideband_msg_hdr hdr; struct drm_dp_sideband_msg_rx *msg = up ? &mgr->up_req_recv : &mgr->down_rep_recv; int basereg = up ? DP_SIDEBAND_MSG_UP_REQ_BASE : DP_SIDEBAND_MSG_DOWN_REP_BASE; if (!up) *mstb = NULL; len = min(mgr->max_dpcd_transaction_bytes, 16); ret = drm_dp_dpcd_read(mgr->aux, basereg, replyblock, len); if (ret != len) { drm_dbg_kms(mgr->dev, "failed to read DPCD down rep %d %d\n", len, ret); return false; } ret = drm_dp_decode_sideband_msg_hdr(mgr, &hdr, replyblock, len, &hdrlen); if (ret == false) { print_hex_dump(KERN_DEBUG, "failed hdr", DUMP_PREFIX_NONE, 16, 1, replyblock, len, false); drm_dbg_kms(mgr->dev, "ERROR: failed header\n"); return false; } if (!up) { /* Caller is responsible for giving back this reference */ *mstb = drm_dp_get_mst_branch_device(mgr, hdr.lct, hdr.rad); if (!*mstb) { drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr.lct); return false; } } if (!drm_dp_sideband_msg_set_header(msg, &hdr, hdrlen)) { drm_dbg_kms(mgr->dev, "sideband msg set header failed %d\n", replyblock[0]); return false; } replylen = min(msg->curchunk_len, (u8)(len - hdrlen)); ret = drm_dp_sideband_append_payload(msg, replyblock + hdrlen, replylen); if (!ret) { drm_dbg_kms(mgr->dev, "sideband msg build failed %d\n", replyblock[0]); return false; } replylen = msg->curchunk_len + msg->curchunk_hdrlen - len; curreply = len; while (replylen > 0) { len = min3(replylen, mgr->max_dpcd_transaction_bytes, 16); ret = drm_dp_dpcd_read(mgr->aux, basereg + curreply, replyblock, len); if (ret != len) { drm_dbg_kms(mgr->dev, "failed to read a chunk (len %d, ret %d)\n", len, ret); return false; } ret = drm_dp_sideband_append_payload(msg, replyblock, len); if (!ret) { drm_dbg_kms(mgr->dev, "failed to build sideband msg\n"); return false; } curreply += len; replylen -= len; } return true; } static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_sideband_msg_tx *txmsg; struct drm_dp_mst_branch *mstb = NULL; struct drm_dp_sideband_msg_rx *msg = &mgr->down_rep_recv; if (!drm_dp_get_one_sb_msg(mgr, false, &mstb)) goto out_clear_reply; /* Multi-packet message transmission, don't clear the reply */ if (!msg->have_eomt) goto out; /* find the message */ mutex_lock(&mgr->qlock); txmsg = list_first_entry_or_null(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); mutex_unlock(&mgr->qlock); /* Were we actually expecting a response, and from this mstb? */ if (!txmsg || txmsg->dst != mstb) { struct drm_dp_sideband_msg_hdr *hdr; hdr = &msg->initial_hdr; drm_dbg_kms(mgr->dev, "Got MST reply with no msg %p %d %d %02x %02x\n", mstb, hdr->seqno, hdr->lct, hdr->rad[0], msg->msg[0]); goto out_clear_reply; } drm_dp_sideband_parse_reply(mgr, msg, &txmsg->reply); if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { drm_dbg_kms(mgr->dev, "Got NAK reply: req 0x%02x (%s), reason 0x%02x (%s), nak data 0x%02x\n", txmsg->reply.req_type, drm_dp_mst_req_type_str(txmsg->reply.req_type), txmsg->reply.u.nak.reason, drm_dp_mst_nak_reason_str(txmsg->reply.u.nak.reason), txmsg->reply.u.nak.nak_data); } memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx)); drm_dp_mst_topology_put_mstb(mstb); mutex_lock(&mgr->qlock); txmsg->state = DRM_DP_SIDEBAND_TX_RX; list_del(&txmsg->next); mutex_unlock(&mgr->qlock); wake_up_all(&mgr->tx_waitq); return 0; out_clear_reply: memset(msg, 0, sizeof(struct drm_dp_sideband_msg_rx)); out: if (mstb) drm_dp_mst_topology_put_mstb(mstb); return 0; } static inline bool drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_pending_up_req *up_req) { struct drm_dp_mst_branch *mstb = NULL; struct drm_dp_sideband_msg_req_body *msg = &up_req->msg; struct drm_dp_sideband_msg_hdr *hdr = &up_req->hdr; bool hotplug = false, dowork = false; if (hdr->broadcast) { const u8 *guid = NULL; if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) guid = msg->u.conn_stat.guid; else if (msg->req_type == DP_RESOURCE_STATUS_NOTIFY) guid = msg->u.resource_stat.guid; if (guid) mstb = drm_dp_get_mst_branch_device_by_guid(mgr, guid); } else { mstb = drm_dp_get_mst_branch_device(mgr, hdr->lct, hdr->rad); } if (!mstb) { drm_dbg_kms(mgr->dev, "Got MST reply from unknown device %d\n", hdr->lct); return false; } /* TODO: Add missing handler for DP_RESOURCE_STATUS_NOTIFY events */ if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) { dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat); hotplug = true; } drm_dp_mst_topology_put_mstb(mstb); if (dowork) queue_work(system_long_wq, &mgr->work); return hotplug; } static void drm_dp_mst_up_req_work(struct work_struct *work) { struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, up_req_work); struct drm_dp_pending_up_req *up_req; bool send_hotplug = false; mutex_lock(&mgr->probe_lock); while (true) { mutex_lock(&mgr->up_req_lock); up_req = list_first_entry_or_null(&mgr->up_req_list, struct drm_dp_pending_up_req, next); if (up_req) list_del(&up_req->next); mutex_unlock(&mgr->up_req_lock); if (!up_req) break; send_hotplug |= drm_dp_mst_process_up_req(mgr, up_req); kfree(up_req); } mutex_unlock(&mgr->probe_lock); if (send_hotplug) drm_kms_helper_hotplug_event(mgr->dev); } static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_pending_up_req *up_req; if (!drm_dp_get_one_sb_msg(mgr, true, NULL)) goto out; if (!mgr->up_req_recv.have_eomt) return 0; up_req = kzalloc(sizeof(*up_req), GFP_KERNEL); if (!up_req) return -ENOMEM; INIT_LIST_HEAD(&up_req->next); drm_dp_sideband_parse_req(mgr, &mgr->up_req_recv, &up_req->msg); if (up_req->msg.req_type != DP_CONNECTION_STATUS_NOTIFY && up_req->msg.req_type != DP_RESOURCE_STATUS_NOTIFY) { drm_dbg_kms(mgr->dev, "Received unknown up req type, ignoring: %x\n", up_req->msg.req_type); kfree(up_req); goto out; } drm_dp_send_up_ack_reply(mgr, mgr->mst_primary, up_req->msg.req_type, false); if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) { const struct drm_dp_connection_status_notify *conn_stat = &up_req->msg.u.conn_stat; bool handle_csn; drm_dbg_kms(mgr->dev, "Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n", conn_stat->port_number, conn_stat->legacy_device_plug_status, conn_stat->displayport_device_plug_status, conn_stat->message_capability_status, conn_stat->input_port, conn_stat->peer_device_type); mutex_lock(&mgr->probe_lock); handle_csn = mgr->mst_primary->link_address_sent; mutex_unlock(&mgr->probe_lock); if (!handle_csn) { drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it."); kfree(up_req); goto out; } } else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) { const struct drm_dp_resource_status_notify *res_stat = &up_req->msg.u.resource_stat; drm_dbg_kms(mgr->dev, "Got RSN: pn: %d avail_pbn %d\n", res_stat->port_number, res_stat->available_pbn); } up_req->hdr = mgr->up_req_recv.initial_hdr; mutex_lock(&mgr->up_req_lock); list_add_tail(&up_req->next, &mgr->up_req_list); mutex_unlock(&mgr->up_req_lock); queue_work(system_long_wq, &mgr->up_req_work); out: memset(&mgr->up_req_recv, 0, sizeof(struct drm_dp_sideband_msg_rx)); return 0; } /** * drm_dp_mst_hpd_irq_handle_event() - MST hotplug IRQ handle MST event * @mgr: manager to notify irq for. * @esi: 4 bytes from SINK_COUNT_ESI * @ack: 4 bytes used to ack events starting from SINK_COUNT_ESI * @handled: whether the hpd interrupt was consumed or not * * This should be called from the driver when it detects a HPD IRQ, * along with the value of the DEVICE_SERVICE_IRQ_VECTOR_ESI0. The * topology manager will process the sideband messages received * as indicated in the DEVICE_SERVICE_IRQ_VECTOR_ESI0 and set the * corresponding flags that Driver has to ack the DP receiver later. * * Note that driver shall also call * drm_dp_mst_hpd_irq_send_new_request() if the 'handled' is set * after calling this function, to try to kick off a new request in * the queue if the previous message transaction is completed. * * See also: * drm_dp_mst_hpd_irq_send_new_request() */ int drm_dp_mst_hpd_irq_handle_event(struct drm_dp_mst_topology_mgr *mgr, const u8 *esi, u8 *ack, bool *handled) { int ret = 0; int sc; *handled = false; sc = DP_GET_SINK_COUNT(esi[0]); if (sc != mgr->sink_count) { mgr->sink_count = sc; *handled = true; } if (esi[1] & DP_DOWN_REP_MSG_RDY) { ret = drm_dp_mst_handle_down_rep(mgr); *handled = true; ack[1] |= DP_DOWN_REP_MSG_RDY; } if (esi[1] & DP_UP_REQ_MSG_RDY) { ret |= drm_dp_mst_handle_up_req(mgr); *handled = true; ack[1] |= DP_UP_REQ_MSG_RDY; } return ret; } EXPORT_SYMBOL(drm_dp_mst_hpd_irq_handle_event); /** * drm_dp_mst_hpd_irq_send_new_request() - MST hotplug IRQ kick off new request * @mgr: manager to notify irq for. * * This should be called from the driver when mst irq event is handled * and acked. Note that new down request should only be sent when * previous message transaction is completed. Source is not supposed to generate * interleaved message transactions. */ void drm_dp_mst_hpd_irq_send_new_request(struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_sideband_msg_tx *txmsg; bool kick = true; mutex_lock(&mgr->qlock); txmsg = list_first_entry_or_null(&mgr->tx_msg_downq, struct drm_dp_sideband_msg_tx, next); /* If last transaction is not completed yet*/ if (!txmsg || txmsg->state == DRM_DP_SIDEBAND_TX_START_SEND || txmsg->state == DRM_DP_SIDEBAND_TX_SENT) kick = false; mutex_unlock(&mgr->qlock); if (kick) drm_dp_mst_kick_tx(mgr); } EXPORT_SYMBOL(drm_dp_mst_hpd_irq_send_new_request); /** * drm_dp_mst_detect_port() - get connection status for an MST port * @connector: DRM connector for this port * @ctx: The acquisition context to use for grabbing locks * @mgr: manager for this port * @port: pointer to a port * * This returns the current connection state for a port. */ int drm_dp_mst_detect_port(struct drm_connector *connector, struct drm_modeset_acquire_ctx *ctx, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { int ret; /* we need to search for the port in the mgr in case it's gone */ port = drm_dp_mst_topology_get_port_validated(mgr, port); if (!port) return connector_status_disconnected; ret = drm_modeset_lock(&mgr->base.lock, ctx); if (ret) goto out; ret = connector_status_disconnected; if (!port->ddps) goto out; switch (port->pdt) { case DP_PEER_DEVICE_NONE: break; case DP_PEER_DEVICE_MST_BRANCHING: if (!port->mcs) ret = connector_status_connected; break; case DP_PEER_DEVICE_SST_SINK: ret = connector_status_connected; /* for logical ports - cache the EDID */ if (drm_dp_mst_port_is_logical(port) && !port->cached_edid) port->cached_edid = drm_edid_read_ddc(connector, &port->aux.ddc); break; case DP_PEER_DEVICE_DP_LEGACY_CONV: if (port->ldps) ret = connector_status_connected; break; } out: drm_dp_mst_topology_put_port(port); return ret; } EXPORT_SYMBOL(drm_dp_mst_detect_port); /** * drm_dp_mst_edid_read() - get EDID for an MST port * @connector: toplevel connector to get EDID for * @mgr: manager for this port * @port: unverified pointer to a port. * * This returns an EDID for the port connected to a connector, * It validates the pointer still exists so the caller doesn't require a * reference. */ const struct drm_edid *drm_dp_mst_edid_read(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { const struct drm_edid *drm_edid; /* we need to search for the port in the mgr in case it's gone */ port = drm_dp_mst_topology_get_port_validated(mgr, port); if (!port) return NULL; if (port->cached_edid) drm_edid = drm_edid_dup(port->cached_edid); else drm_edid = drm_edid_read_ddc(connector, &port->aux.ddc); drm_dp_mst_topology_put_port(port); return drm_edid; } EXPORT_SYMBOL(drm_dp_mst_edid_read); /** * drm_dp_mst_get_edid() - get EDID for an MST port * @connector: toplevel connector to get EDID for * @mgr: manager for this port * @port: unverified pointer to a port. * * This function is deprecated; please use drm_dp_mst_edid_read() instead. * * This returns an EDID for the port connected to a connector, * It validates the pointer still exists so the caller doesn't require a * reference. */ struct edid *drm_dp_mst_get_edid(struct drm_connector *connector, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { const struct drm_edid *drm_edid; struct edid *edid; drm_edid = drm_dp_mst_edid_read(connector, mgr, port); edid = drm_edid_duplicate(drm_edid_raw(drm_edid)); drm_edid_free(drm_edid); return edid; } EXPORT_SYMBOL(drm_dp_mst_get_edid); /** * drm_dp_atomic_find_time_slots() - Find and add time slots to the state * @state: global atomic state * @mgr: MST topology manager for the port * @port: port to find time slots for * @pbn: bandwidth required for the mode in PBN * * Allocates time slots to @port, replacing any previous time slot allocations it may * have had. Any atomic drivers which support MST must call this function in * their &drm_encoder_helper_funcs.atomic_check() callback unconditionally to * change the current time slot allocation for the new state, and ensure the MST * atomic state is added whenever the state of payloads in the topology changes. * * Allocations set by this function are not checked against the bandwidth * restraints of @mgr until the driver calls drm_dp_mst_atomic_check(). * * Additionally, it is OK to call this function multiple times on the same * @port as needed. It is not OK however, to call this function and * drm_dp_atomic_release_time_slots() in the same atomic check phase. * * See also: * drm_dp_atomic_release_time_slots() * drm_dp_mst_atomic_check() * * Returns: * Total slots in the atomic state assigned for this port, or a negative error * code if the port no longer exists */ int drm_dp_atomic_find_time_slots(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, int pbn) { struct drm_dp_mst_topology_state *topology_state; struct drm_dp_mst_atomic_payload *payload = NULL; struct drm_connector_state *conn_state; int prev_slots = 0, prev_bw = 0, req_slots; topology_state = drm_atomic_get_mst_topology_state(state, mgr); if (IS_ERR(topology_state)) return PTR_ERR(topology_state); conn_state = drm_atomic_get_new_connector_state(state, port->connector); topology_state->pending_crtc_mask |= drm_crtc_mask(conn_state->crtc); /* Find the current allocation for this port, if any */ payload = drm_atomic_get_mst_payload_state(topology_state, port); if (payload) { prev_slots = payload->time_slots; prev_bw = payload->pbn; /* * This should never happen, unless the driver tries * releasing and allocating the same timeslot allocation, * which is an error */ if (drm_WARN_ON(mgr->dev, payload->delete)) { drm_err(mgr->dev, "cannot allocate and release time slots on [MST PORT:%p] in the same state\n", port); return -EINVAL; } } req_slots = DIV_ROUND_UP(dfixed_const(pbn), topology_state->pbn_div.full); drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] TU %d -> %d\n", port->connector->base.id, port->connector->name, port, prev_slots, req_slots); drm_dbg_atomic(mgr->dev, "[CONNECTOR:%d:%s] [MST PORT:%p] PBN %d -> %d\n", port->connector->base.id, port->connector->name, port, prev_bw, pbn); /* Add the new allocation to the state, note the VCPI isn't assigned until the end */ if (!payload) { payload = kzalloc(sizeof(*payload), GFP_KERNEL); if (!payload) return -ENOMEM; drm_dp_mst_get_port_malloc(port); payload->port = port; payload->vc_start_slot = -1; payload->payload_allocation_status = DRM_DP_MST_PAYLOAD_ALLOCATION_NONE; list_add(&payload->next, &topology_state->payloads); } payload->time_slots = req_slots; payload->pbn = pbn; return req_slots; } EXPORT_SYMBOL(drm_dp_atomic_find_time_slots); /** * drm_dp_atomic_release_time_slots() - Release allocated time slots * @state: global atomic state * @mgr: MST topology manager for the port * @port: The port to release the time slots from * * Releases any time slots that have been allocated to a port in the atomic * state. Any atomic drivers which support MST must call this function * unconditionally in their &drm_connector_helper_funcs.atomic_check() callback. * This helper will check whether time slots would be released by the new state and * respond accordingly, along with ensuring the MST state is always added to the * atomic state whenever a new state would modify the state of payloads on the * topology. * * It is OK to call this even if @port has been removed from the system. * Additionally, it is OK to call this function multiple times on the same * @port as needed. It is not OK however, to call this function and * drm_dp_atomic_find_time_slots() on the same @port in a single atomic check * phase. * * See also: * drm_dp_atomic_find_time_slots() * drm_dp_mst_atomic_check() * * Returns: * 0 on success, negative error code otherwise */ int drm_dp_atomic_release_time_slots(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port) { struct drm_dp_mst_topology_state *topology_state; struct drm_dp_mst_atomic_payload *payload; struct drm_connector_state *old_conn_state, *new_conn_state; bool update_payload = true; old_conn_state = drm_atomic_get_old_connector_state(state, port->connector); if (!old_conn_state->crtc) return 0; /* If the CRTC isn't disabled by this state, don't release it's payload */ new_conn_state = drm_atomic_get_new_connector_state(state, port->connector); if (new_conn_state->crtc) { struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc); /* No modeset means no payload changes, so it's safe to not pull in the MST state */ if (!crtc_state || !drm_atomic_crtc_needs_modeset(crtc_state)) return 0; if (!crtc_state->mode_changed && !crtc_state->connectors_changed) update_payload = false; } topology_state = drm_atomic_get_mst_topology_state(state, mgr); if (IS_ERR(topology_state)) return PTR_ERR(topology_state); topology_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc); if (!update_payload) return 0; payload = drm_atomic_get_mst_payload_state(topology_state, port); if (WARN_ON(!payload)) { drm_err(mgr->dev, "No payload for [MST PORT:%p] found in mst state %p\n", port, &topology_state->base); return -EINVAL; } if (new_conn_state->crtc) return 0; drm_dbg_atomic(mgr->dev, "[MST PORT:%p] TU %d -> 0\n", port, payload->time_slots); if (!payload->delete) { payload->pbn = 0; payload->delete = true; topology_state->payload_mask &= ~BIT(payload->vcpi - 1); } return 0; } EXPORT_SYMBOL(drm_dp_atomic_release_time_slots); /** * drm_dp_mst_atomic_setup_commit() - setup_commit hook for MST helpers * @state: global atomic state * * This function saves all of the &drm_crtc_commit structs in an atomic state that touch any CRTCs * currently assigned to an MST topology. Drivers must call this hook from their * &drm_mode_config_helper_funcs.atomic_commit_setup hook. * * Returns: * 0 if all CRTC commits were retrieved successfully, negative error code otherwise */ int drm_dp_mst_atomic_setup_commit(struct drm_atomic_state *state) { struct drm_dp_mst_topology_mgr *mgr; struct drm_dp_mst_topology_state *mst_state; struct drm_crtc *crtc; struct drm_crtc_state *crtc_state; int i, j, commit_idx, num_commit_deps; for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) { if (!mst_state->pending_crtc_mask) continue; num_commit_deps = hweight32(mst_state->pending_crtc_mask); mst_state->commit_deps = kmalloc_array(num_commit_deps, sizeof(*mst_state->commit_deps), GFP_KERNEL); if (!mst_state->commit_deps) return -ENOMEM; mst_state->num_commit_deps = num_commit_deps; commit_idx = 0; for_each_new_crtc_in_state(state, crtc, crtc_state, j) { if (mst_state->pending_crtc_mask & drm_crtc_mask(crtc)) { mst_state->commit_deps[commit_idx++] = drm_crtc_commit_get(crtc_state->commit); } } } return 0; } EXPORT_SYMBOL(drm_dp_mst_atomic_setup_commit); /** * drm_dp_mst_atomic_wait_for_dependencies() - Wait for all pending commits on MST topologies, * prepare new MST state for commit * @state: global atomic state * * Goes through any MST topologies in this atomic state, and waits for any pending commits which * touched CRTCs that were/are on an MST topology to be programmed to hardware and flipped to before * returning. This is to prevent multiple non-blocking commits affecting an MST topology from racing * with eachother by forcing them to be executed sequentially in situations where the only resources * the modeset objects in these commits share are an MST topology. * * This function also prepares the new MST state for commit by performing some state preparation * which can't be done until this point, such as reading back the final VC start slots (which are * determined at commit-time) from the previous state. * * All MST drivers must call this function after calling drm_atomic_helper_wait_for_dependencies(), * or whatever their equivalent of that is. */ void drm_dp_mst_atomic_wait_for_dependencies(struct drm_atomic_state *state) { struct drm_dp_mst_topology_state *old_mst_state, *new_mst_state; struct drm_dp_mst_topology_mgr *mgr; struct drm_dp_mst_atomic_payload *old_payload, *new_payload; int i, j, ret; for_each_oldnew_mst_mgr_in_state(state, mgr, old_mst_state, new_mst_state, i) { for (j = 0; j < old_mst_state->num_commit_deps; j++) { ret = drm_crtc_commit_wait(old_mst_state->commit_deps[j]); if (ret < 0) drm_err(state->dev, "Failed to wait for %s: %d\n", old_mst_state->commit_deps[j]->crtc->name, ret); } /* Now that previous state is committed, it's safe to copy over the start slot * and allocation status assignments */ list_for_each_entry(old_payload, &old_mst_state->payloads, next) { if (old_payload->delete) continue; new_payload = drm_atomic_get_mst_payload_state(new_mst_state, old_payload->port); new_payload->vc_start_slot = old_payload->vc_start_slot; new_payload->payload_allocation_status = old_payload->payload_allocation_status; } } } EXPORT_SYMBOL(drm_dp_mst_atomic_wait_for_dependencies); /** * drm_dp_mst_root_conn_atomic_check() - Serialize CRTC commits on MST-capable connectors operating * in SST mode * @new_conn_state: The new connector state of the &drm_connector * @mgr: The MST topology manager for the &drm_connector * * Since MST uses fake &drm_encoder structs, the generic atomic modesetting code isn't able to * serialize non-blocking commits happening on the real DP connector of an MST topology switching * into/away from MST mode - as the CRTC on the real DP connector and the CRTCs on the connector's * MST topology will never share the same &drm_encoder. * * This function takes care of this serialization issue, by checking a root MST connector's atomic * state to determine if it is about to have a modeset - and then pulling in the MST topology state * if so, along with adding any relevant CRTCs to &drm_dp_mst_topology_state.pending_crtc_mask. * * Drivers implementing MST must call this function from the * &drm_connector_helper_funcs.atomic_check hook of any physical DP &drm_connector capable of * driving MST sinks. * * Returns: * 0 on success, negative error code otherwise */ int drm_dp_mst_root_conn_atomic_check(struct drm_connector_state *new_conn_state, struct drm_dp_mst_topology_mgr *mgr) { struct drm_atomic_state *state = new_conn_state->state; struct drm_connector_state *old_conn_state = drm_atomic_get_old_connector_state(state, new_conn_state->connector); struct drm_crtc_state *crtc_state; struct drm_dp_mst_topology_state *mst_state = NULL; if (new_conn_state->crtc) { crtc_state = drm_atomic_get_new_crtc_state(state, new_conn_state->crtc); if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) { mst_state = drm_atomic_get_mst_topology_state(state, mgr); if (IS_ERR(mst_state)) return PTR_ERR(mst_state); mst_state->pending_crtc_mask |= drm_crtc_mask(new_conn_state->crtc); } } if (old_conn_state->crtc) { crtc_state = drm_atomic_get_new_crtc_state(state, old_conn_state->crtc); if (crtc_state && drm_atomic_crtc_needs_modeset(crtc_state)) { if (!mst_state) { mst_state = drm_atomic_get_mst_topology_state(state, mgr); if (IS_ERR(mst_state)) return PTR_ERR(mst_state); } mst_state->pending_crtc_mask |= drm_crtc_mask(old_conn_state->crtc); } } return 0; } EXPORT_SYMBOL(drm_dp_mst_root_conn_atomic_check); /** * drm_dp_mst_update_slots() - updates the slot info depending on the DP ecoding format * @mst_state: mst_state to update * @link_encoding_cap: the ecoding format on the link */ void drm_dp_mst_update_slots(struct drm_dp_mst_topology_state *mst_state, uint8_t link_encoding_cap) { if (link_encoding_cap == DP_CAP_ANSI_128B132B) { mst_state->total_avail_slots = 64; mst_state->start_slot = 0; } else { mst_state->total_avail_slots = 63; mst_state->start_slot = 1; } DRM_DEBUG_KMS("%s encoding format on mst_state 0x%p\n", (link_encoding_cap == DP_CAP_ANSI_128B132B) ? "128b/132b":"8b/10b", mst_state); } EXPORT_SYMBOL(drm_dp_mst_update_slots); static int drm_dp_dpcd_write_payload(struct drm_dp_mst_topology_mgr *mgr, int id, u8 start_slot, u8 num_slots) { u8 payload_alloc[3], status; int ret; int retries = 0; drm_dp_dpcd_writeb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, DP_PAYLOAD_TABLE_UPDATED); payload_alloc[0] = id; payload_alloc[1] = start_slot; payload_alloc[2] = num_slots; ret = drm_dp_dpcd_write(mgr->aux, DP_PAYLOAD_ALLOCATE_SET, payload_alloc, 3); if (ret != 3) { drm_dbg_kms(mgr->dev, "failed to write payload allocation %d\n", ret); goto fail; } retry: ret = drm_dp_dpcd_readb(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); if (ret < 0) { drm_dbg_kms(mgr->dev, "failed to read payload table status %d\n", ret); goto fail; } if (!(status & DP_PAYLOAD_TABLE_UPDATED)) { retries++; if (retries < 20) { usleep_range(10000, 20000); goto retry; } drm_dbg_kms(mgr->dev, "status not set after read payload table status %d\n", status); ret = -EINVAL; goto fail; } ret = 0; fail: return ret; } static int do_get_act_status(struct drm_dp_aux *aux) { int ret; u8 status; ret = drm_dp_dpcd_readb(aux, DP_PAYLOAD_TABLE_UPDATE_STATUS, &status); if (ret < 0) return ret; return status; } /** * drm_dp_check_act_status() - Polls for ACT handled status. * @mgr: manager to use * * Tries waiting for the MST hub to finish updating it's payload table by * polling for the ACT handled bit for up to 3 seconds (yes-some hubs really * take that long). * * Returns: * 0 if the ACT was handled in time, negative error code on failure. */ int drm_dp_check_act_status(struct drm_dp_mst_topology_mgr *mgr) { /* * There doesn't seem to be any recommended retry count or timeout in * the MST specification. Since some hubs have been observed to take * over 1 second to update their payload allocations under certain * conditions, we use a rather large timeout value. */ const int timeout_ms = 3000; int ret, status; ret = readx_poll_timeout(do_get_act_status, mgr->aux, status, status & DP_PAYLOAD_ACT_HANDLED || status < 0, 200, timeout_ms * USEC_PER_MSEC); if (ret < 0 && status >= 0) { drm_err(mgr->dev, "Failed to get ACT after %dms, last status: %02x\n", timeout_ms, status); return -EINVAL; } else if (status < 0) { /* * Failure here isn't unexpected - the hub may have * just been unplugged */ drm_dbg_kms(mgr->dev, "Failed to read payload table status: %d\n", status); return status; } return 0; } EXPORT_SYMBOL(drm_dp_check_act_status); /** * drm_dp_calc_pbn_mode() - Calculate the PBN for a mode. * @clock: dot clock * @bpp: bpp as .4 binary fixed point * * This uses the formula in the spec to calculate the PBN value for a mode. */ int drm_dp_calc_pbn_mode(int clock, int bpp) { /* * The unit of 54/64Mbytes/sec is an arbitrary unit chosen based on * common multiplier to render an integer PBN for all link rate/lane * counts combinations * calculate * peak_kbps = clock * bpp / 16 * peak_kbps *= SSC overhead / 1000000 * peak_kbps /= 8 convert to Kbytes * peak_kBps *= (64/54) / 1000 convert to PBN */ /* * TODO: Use the actual link and mode parameters to calculate * the overhead. For now it's assumed that these are * 4 link lanes, 4096 hactive pixels, which don't add any * significant data padding overhead and that there is no DSC * or FEC overhead. */ int overhead = drm_dp_bw_overhead(4, 4096, 0, bpp, DRM_DP_BW_OVERHEAD_MST | DRM_DP_BW_OVERHEAD_SSC_REF_CLK); return DIV64_U64_ROUND_UP(mul_u32_u32(clock * bpp, 64 * overhead >> 4), 1000000ULL * 8 * 54 * 1000); } EXPORT_SYMBOL(drm_dp_calc_pbn_mode); /* we want to kick the TX after we've ack the up/down IRQs. */ static void drm_dp_mst_kick_tx(struct drm_dp_mst_topology_mgr *mgr) { queue_work(system_long_wq, &mgr->tx_work); } /* * Helper function for parsing DP device types into convenient strings * for use with dp_mst_topology */ static const char *pdt_to_string(u8 pdt) { switch (pdt) { case DP_PEER_DEVICE_NONE: return "NONE"; case DP_PEER_DEVICE_SOURCE_OR_SST: return "SOURCE OR SST"; case DP_PEER_DEVICE_MST_BRANCHING: return "MST BRANCHING"; case DP_PEER_DEVICE_SST_SINK: return "SST SINK"; case DP_PEER_DEVICE_DP_LEGACY_CONV: return "DP LEGACY CONV"; default: return "ERR"; } } static void drm_dp_mst_dump_mstb(struct seq_file *m, struct drm_dp_mst_branch *mstb) { struct drm_dp_mst_port *port; int tabs = mstb->lct; char prefix[10]; int i; for (i = 0; i < tabs; i++) prefix[i] = '\t'; prefix[i] = '\0'; seq_printf(m, "%smstb - [%p]: num_ports: %d\n", prefix, mstb, mstb->num_ports); list_for_each_entry(port, &mstb->ports, next) { seq_printf(m, "%sport %d - [%p] (%s - %s): ddps: %d, ldps: %d, sdp: %d/%d, fec: %s, conn: %p\n", prefix, port->port_num, port, port->input ? "input" : "output", pdt_to_string(port->pdt), port->ddps, port->ldps, port->num_sdp_streams, port->num_sdp_stream_sinks, port->fec_capable ? "true" : "false", port->connector); if (port->mstb) drm_dp_mst_dump_mstb(m, port->mstb); } } #define DP_PAYLOAD_TABLE_SIZE 64 static bool dump_dp_payload_table(struct drm_dp_mst_topology_mgr *mgr, char *buf) { int i; for (i = 0; i < DP_PAYLOAD_TABLE_SIZE; i += 16) { if (drm_dp_dpcd_read(mgr->aux, DP_PAYLOAD_TABLE_UPDATE_STATUS + i, &buf[i], 16) != 16) return false; } return true; } static void fetch_monitor_name(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, char *name, int namelen) { struct edid *mst_edid; mst_edid = drm_dp_mst_get_edid(port->connector, mgr, port); drm_edid_get_monitor_name(mst_edid, name, namelen); kfree(mst_edid); } /** * drm_dp_mst_dump_topology(): dump topology to seq file. * @m: seq_file to dump output to * @mgr: manager to dump current topology for. * * helper to dump MST topology to a seq file for debugfs. */ void drm_dp_mst_dump_topology(struct seq_file *m, struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_mst_topology_state *state; struct drm_dp_mst_atomic_payload *payload; int i, ret; static const char *const status[] = { "None", "Local", "DFP", "Remote", }; mutex_lock(&mgr->lock); if (mgr->mst_primary) drm_dp_mst_dump_mstb(m, mgr->mst_primary); /* dump VCPIs */ mutex_unlock(&mgr->lock); ret = drm_modeset_lock_single_interruptible(&mgr->base.lock); if (ret < 0) return; state = to_drm_dp_mst_topology_state(mgr->base.state); seq_printf(m, "\n*** Atomic state info ***\n"); seq_printf(m, "payload_mask: %x, max_payloads: %d, start_slot: %u, pbn_div: %d\n", state->payload_mask, mgr->max_payloads, state->start_slot, dfixed_trunc(state->pbn_div)); seq_printf(m, "\n| idx | port | vcpi | slots | pbn | dsc | status | sink name |\n"); for (i = 0; i < mgr->max_payloads; i++) { list_for_each_entry(payload, &state->payloads, next) { char name[14]; if (payload->vcpi != i || payload->delete) continue; fetch_monitor_name(mgr, payload->port, name, sizeof(name)); seq_printf(m, " %5d %6d %6d %02d - %02d %5d %5s %8s %19s\n", i, payload->port->port_num, payload->vcpi, payload->vc_start_slot, payload->vc_start_slot + payload->time_slots - 1, payload->pbn, payload->dsc_enabled ? "Y" : "N", status[payload->payload_allocation_status], (*name != 0) ? name : "Unknown"); } } seq_printf(m, "\n*** DPCD Info ***\n"); mutex_lock(&mgr->lock); if (mgr->mst_primary) { u8 buf[DP_PAYLOAD_TABLE_SIZE]; int ret; if (drm_dp_read_dpcd_caps(mgr->aux, buf) < 0) { seq_printf(m, "dpcd read failed\n"); goto out; } seq_printf(m, "dpcd: %*ph\n", DP_RECEIVER_CAP_SIZE, buf); ret = drm_dp_dpcd_read(mgr->aux, DP_FAUX_CAP, buf, 2); if (ret != 2) { seq_printf(m, "faux/mst read failed\n"); goto out; } seq_printf(m, "faux/mst: %*ph\n", 2, buf); ret = drm_dp_dpcd_read(mgr->aux, DP_MSTM_CTRL, buf, 1); if (ret != 1) { seq_printf(m, "mst ctrl read failed\n"); goto out; } seq_printf(m, "mst ctrl: %*ph\n", 1, buf); /* dump the standard OUI branch header */ ret = drm_dp_dpcd_read(mgr->aux, DP_BRANCH_OUI, buf, DP_BRANCH_OUI_HEADER_SIZE); if (ret != DP_BRANCH_OUI_HEADER_SIZE) { seq_printf(m, "branch oui read failed\n"); goto out; } seq_printf(m, "branch oui: %*phN devid: ", 3, buf); for (i = 0x3; i < 0x8 && buf[i]; i++) seq_printf(m, "%c", buf[i]); seq_printf(m, " revision: hw: %x.%x sw: %x.%x\n", buf[0x9] >> 4, buf[0x9] & 0xf, buf[0xa], buf[0xb]); if (dump_dp_payload_table(mgr, buf)) seq_printf(m, "payload table: %*ph\n", DP_PAYLOAD_TABLE_SIZE, buf); } out: mutex_unlock(&mgr->lock); drm_modeset_unlock(&mgr->base.lock); } EXPORT_SYMBOL(drm_dp_mst_dump_topology); static void drm_dp_tx_work(struct work_struct *work) { struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, tx_work); mutex_lock(&mgr->qlock); if (!list_empty(&mgr->tx_msg_downq)) process_single_down_tx_qlock(mgr); mutex_unlock(&mgr->qlock); } static inline void drm_dp_delayed_destroy_port(struct drm_dp_mst_port *port) { drm_dp_port_set_pdt(port, DP_PEER_DEVICE_NONE, port->mcs); if (port->connector) { drm_connector_unregister(port->connector); drm_connector_put(port->connector); } drm_dp_mst_put_port_malloc(port); } static inline void drm_dp_delayed_destroy_mstb(struct drm_dp_mst_branch *mstb) { struct drm_dp_mst_topology_mgr *mgr = mstb->mgr; struct drm_dp_mst_port *port, *port_tmp; struct drm_dp_sideband_msg_tx *txmsg, *txmsg_tmp; bool wake_tx = false; mutex_lock(&mgr->lock); list_for_each_entry_safe(port, port_tmp, &mstb->ports, next) { list_del(&port->next); drm_dp_mst_topology_put_port(port); } mutex_unlock(&mgr->lock); /* drop any tx slot msg */ mutex_lock(&mstb->mgr->qlock); list_for_each_entry_safe(txmsg, txmsg_tmp, &mgr->tx_msg_downq, next) { if (txmsg->dst != mstb) continue; txmsg->state = DRM_DP_SIDEBAND_TX_TIMEOUT; list_del(&txmsg->next); wake_tx = true; } mutex_unlock(&mstb->mgr->qlock); if (wake_tx) wake_up_all(&mstb->mgr->tx_waitq); drm_dp_mst_put_mstb_malloc(mstb); } static void drm_dp_delayed_destroy_work(struct work_struct *work) { struct drm_dp_mst_topology_mgr *mgr = container_of(work, struct drm_dp_mst_topology_mgr, delayed_destroy_work); bool send_hotplug = false, go_again; /* * Not a regular list traverse as we have to drop the destroy * connector lock before destroying the mstb/port, to avoid AB->BA * ordering between this lock and the config mutex. */ do { go_again = false; for (;;) { struct drm_dp_mst_branch *mstb; mutex_lock(&mgr->delayed_destroy_lock); mstb = list_first_entry_or_null(&mgr->destroy_branch_device_list, struct drm_dp_mst_branch, destroy_next); if (mstb) list_del(&mstb->destroy_next); mutex_unlock(&mgr->delayed_destroy_lock); if (!mstb) break; drm_dp_delayed_destroy_mstb(mstb); go_again = true; } for (;;) { struct drm_dp_mst_port *port; mutex_lock(&mgr->delayed_destroy_lock); port = list_first_entry_or_null(&mgr->destroy_port_list, struct drm_dp_mst_port, next); if (port) list_del(&port->next); mutex_unlock(&mgr->delayed_destroy_lock); if (!port) break; drm_dp_delayed_destroy_port(port); send_hotplug = true; go_again = true; } } while (go_again); if (send_hotplug) drm_kms_helper_hotplug_event(mgr->dev); } static struct drm_private_state * drm_dp_mst_duplicate_state(struct drm_private_obj *obj) { struct drm_dp_mst_topology_state *state, *old_state = to_dp_mst_topology_state(obj->state); struct drm_dp_mst_atomic_payload *pos, *payload; state = kmemdup(old_state, sizeof(*state), GFP_KERNEL); if (!state) return NULL; __drm_atomic_helper_private_obj_duplicate_state(obj, &state->base); INIT_LIST_HEAD(&state->payloads); state->commit_deps = NULL; state->num_commit_deps = 0; state->pending_crtc_mask = 0; list_for_each_entry(pos, &old_state->payloads, next) { /* Prune leftover freed timeslot allocations */ if (pos->delete) continue; payload = kmemdup(pos, sizeof(*payload), GFP_KERNEL); if (!payload) goto fail; drm_dp_mst_get_port_malloc(payload->port); list_add(&payload->next, &state->payloads); } return &state->base; fail: list_for_each_entry_safe(pos, payload, &state->payloads, next) { drm_dp_mst_put_port_malloc(pos->port); kfree(pos); } kfree(state); return NULL; } static void drm_dp_mst_destroy_state(struct drm_private_obj *obj, struct drm_private_state *state) { struct drm_dp_mst_topology_state *mst_state = to_dp_mst_topology_state(state); struct drm_dp_mst_atomic_payload *pos, *tmp; int i; list_for_each_entry_safe(pos, tmp, &mst_state->payloads, next) { /* We only keep references to ports with active payloads */ if (!pos->delete) drm_dp_mst_put_port_malloc(pos->port); kfree(pos); } for (i = 0; i < mst_state->num_commit_deps; i++) drm_crtc_commit_put(mst_state->commit_deps[i]); kfree(mst_state->commit_deps); kfree(mst_state); } static bool drm_dp_mst_port_downstream_of_branch(struct drm_dp_mst_port *port, struct drm_dp_mst_branch *branch) { while (port->parent) { if (port->parent == branch) return true; if (port->parent->port_parent) port = port->parent->port_parent; else break; } return false; } static bool drm_dp_mst_port_downstream_of_parent_locked(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, struct drm_dp_mst_port *parent) { if (!mgr->mst_primary) return false; port = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary, port); if (!port) return false; if (!parent) return true; parent = drm_dp_mst_topology_get_port_validated_locked(mgr->mst_primary, parent); if (!parent) return false; if (!parent->mstb) return false; return drm_dp_mst_port_downstream_of_branch(port, parent->mstb); } /** * drm_dp_mst_port_downstream_of_parent - check if a port is downstream of a parent port * @mgr: MST topology manager * @port: the port being looked up * @parent: the parent port * * The function returns %true if @port is downstream of @parent. If @parent is * %NULL - denoting the root port - the function returns %true if @port is in * @mgr's topology. */ bool drm_dp_mst_port_downstream_of_parent(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_port *port, struct drm_dp_mst_port *parent) { bool ret; mutex_lock(&mgr->lock); ret = drm_dp_mst_port_downstream_of_parent_locked(mgr, port, parent); mutex_unlock(&mgr->lock); return ret; } EXPORT_SYMBOL(drm_dp_mst_port_downstream_of_parent); static int drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port, struct drm_dp_mst_topology_state *state, struct drm_dp_mst_port **failing_port); static int drm_dp_mst_atomic_check_mstb_bw_limit(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_topology_state *state, struct drm_dp_mst_port **failing_port) { struct drm_dp_mst_atomic_payload *payload; struct drm_dp_mst_port *port; int pbn_used = 0, ret; bool found = false; /* Check that we have at least one port in our state that's downstream * of this branch, otherwise we can skip this branch */ list_for_each_entry(payload, &state->payloads, next) { if (!payload->pbn || !drm_dp_mst_port_downstream_of_branch(payload->port, mstb)) continue; found = true; break; } if (!found) return 0; if (mstb->port_parent) drm_dbg_atomic(mstb->mgr->dev, "[MSTB:%p] [MST PORT:%p] Checking bandwidth limits on [MSTB:%p]\n", mstb->port_parent->parent, mstb->port_parent, mstb); else drm_dbg_atomic(mstb->mgr->dev, "[MSTB:%p] Checking bandwidth limits\n", mstb); list_for_each_entry(port, &mstb->ports, next) { ret = drm_dp_mst_atomic_check_port_bw_limit(port, state, failing_port); if (ret < 0) return ret; pbn_used += ret; } return pbn_used; } static int drm_dp_mst_atomic_check_port_bw_limit(struct drm_dp_mst_port *port, struct drm_dp_mst_topology_state *state, struct drm_dp_mst_port **failing_port) { struct drm_dp_mst_atomic_payload *payload; int pbn_used = 0; if (port->pdt == DP_PEER_DEVICE_NONE) return 0; if (drm_dp_mst_is_end_device(port->pdt, port->mcs)) { payload = drm_atomic_get_mst_payload_state(state, port); if (!payload) return 0; /* * This could happen if the sink deasserted its HPD line, but * the branch device still reports it as attached (PDT != NONE). */ if (!port->full_pbn) { drm_dbg_atomic(port->mgr->dev, "[MSTB:%p] [MST PORT:%p] no BW available for the port\n", port->parent, port); *failing_port = port; return -EINVAL; } pbn_used = payload->pbn; } else { pbn_used = drm_dp_mst_atomic_check_mstb_bw_limit(port->mstb, state, failing_port); if (pbn_used <= 0) return pbn_used; } if (pbn_used > port->full_pbn) { drm_dbg_atomic(port->mgr->dev, "[MSTB:%p] [MST PORT:%p] required PBN of %d exceeds port limit of %d\n", port->parent, port, pbn_used, port->full_pbn); *failing_port = port; return -ENOSPC; } drm_dbg_atomic(port->mgr->dev, "[MSTB:%p] [MST PORT:%p] uses %d out of %d PBN\n", port->parent, port, pbn_used, port->full_pbn); return pbn_used; } static inline int drm_dp_mst_atomic_check_payload_alloc_limits(struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state) { struct drm_dp_mst_atomic_payload *payload; int avail_slots = mst_state->total_avail_slots, payload_count = 0; list_for_each_entry(payload, &mst_state->payloads, next) { /* Releasing payloads is always OK-even if the port is gone */ if (payload->delete) { drm_dbg_atomic(mgr->dev, "[MST PORT:%p] releases all time slots\n", payload->port); continue; } drm_dbg_atomic(mgr->dev, "[MST PORT:%p] requires %d time slots\n", payload->port, payload->time_slots); avail_slots -= payload->time_slots; if (avail_slots < 0) { drm_dbg_atomic(mgr->dev, "[MST PORT:%p] not enough time slots in mst state %p (avail=%d)\n", payload->port, mst_state, avail_slots + payload->time_slots); return -ENOSPC; } if (++payload_count > mgr->max_payloads) { drm_dbg_atomic(mgr->dev, "[MST MGR:%p] state %p has too many payloads (max=%d)\n", mgr, mst_state, mgr->max_payloads); return -EINVAL; } /* Assign a VCPI */ if (!payload->vcpi) { payload->vcpi = ffz(mst_state->payload_mask) + 1; drm_dbg_atomic(mgr->dev, "[MST PORT:%p] assigned VCPI #%d\n", payload->port, payload->vcpi); mst_state->payload_mask |= BIT(payload->vcpi - 1); } } if (!payload_count) mst_state->pbn_div.full = dfixed_const(0); drm_dbg_atomic(mgr->dev, "[MST MGR:%p] mst state %p TU pbn_div=%d avail=%d used=%d\n", mgr, mst_state, dfixed_trunc(mst_state->pbn_div), avail_slots, mst_state->total_avail_slots - avail_slots); return 0; } /** * drm_dp_mst_add_affected_dsc_crtcs * @state: Pointer to the new struct drm_dp_mst_topology_state * @mgr: MST topology manager * * Whenever there is a change in mst topology * DSC configuration would have to be recalculated * therefore we need to trigger modeset on all affected * CRTCs in that topology * * See also: * drm_dp_mst_atomic_enable_dsc() */ int drm_dp_mst_add_affected_dsc_crtcs(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) { struct drm_dp_mst_topology_state *mst_state; struct drm_dp_mst_atomic_payload *pos; struct drm_connector *connector; struct drm_connector_state *conn_state; struct drm_crtc *crtc; struct drm_crtc_state *crtc_state; mst_state = drm_atomic_get_mst_topology_state(state, mgr); if (IS_ERR(mst_state)) return PTR_ERR(mst_state); list_for_each_entry(pos, &mst_state->payloads, next) { connector = pos->port->connector; if (!connector) return -EINVAL; conn_state = drm_atomic_get_connector_state(state, connector); if (IS_ERR(conn_state)) return PTR_ERR(conn_state); crtc = conn_state->crtc; if (!crtc) continue; if (!drm_dp_mst_dsc_aux_for_port(pos->port)) continue; crtc_state = drm_atomic_get_crtc_state(mst_state->base.state, crtc); if (IS_ERR(crtc_state)) return PTR_ERR(crtc_state); drm_dbg_atomic(mgr->dev, "[MST MGR:%p] Setting mode_changed flag on CRTC %p\n", mgr, crtc); crtc_state->mode_changed = true; } return 0; } EXPORT_SYMBOL(drm_dp_mst_add_affected_dsc_crtcs); /** * drm_dp_mst_atomic_enable_dsc - Set DSC Enable Flag to On/Off * @state: Pointer to the new drm_atomic_state * @port: Pointer to the affected MST Port * @pbn: Newly recalculated bw required for link with DSC enabled * @enable: Boolean flag to enable or disable DSC on the port * * This function enables DSC on the given Port * by recalculating its vcpi from pbn provided * and sets dsc_enable flag to keep track of which * ports have DSC enabled * */ int drm_dp_mst_atomic_enable_dsc(struct drm_atomic_state *state, struct drm_dp_mst_port *port, int pbn, bool enable) { struct drm_dp_mst_topology_state *mst_state; struct drm_dp_mst_atomic_payload *payload; int time_slots = 0; mst_state = drm_atomic_get_mst_topology_state(state, port->mgr); if (IS_ERR(mst_state)) return PTR_ERR(mst_state); payload = drm_atomic_get_mst_payload_state(mst_state, port); if (!payload) { drm_dbg_atomic(state->dev, "[MST PORT:%p] Couldn't find payload in mst state %p\n", port, mst_state); return -EINVAL; } if (payload->dsc_enabled == enable) { drm_dbg_atomic(state->dev, "[MST PORT:%p] DSC flag is already set to %d, returning %d time slots\n", port, enable, payload->time_slots); time_slots = payload->time_slots; } if (enable) { time_slots = drm_dp_atomic_find_time_slots(state, port->mgr, port, pbn); drm_dbg_atomic(state->dev, "[MST PORT:%p] Enabling DSC flag, reallocating %d time slots on the port\n", port, time_slots); if (time_slots < 0) return -EINVAL; } payload->dsc_enabled = enable; return time_slots; } EXPORT_SYMBOL(drm_dp_mst_atomic_enable_dsc); /** * drm_dp_mst_atomic_check_mgr - Check the atomic state of an MST topology manager * @state: The global atomic state * @mgr: Manager to check * @mst_state: The MST atomic state for @mgr * @failing_port: Returns the port with a BW limitation * * Checks the given MST manager's topology state for an atomic update to ensure * that it's valid. This includes checking whether there's enough bandwidth to * support the new timeslot allocations in the atomic update. * * Any atomic drivers supporting DP MST must make sure to call this or * the drm_dp_mst_atomic_check() function after checking the rest of their state * in their &drm_mode_config_funcs.atomic_check() callback. * * See also: * drm_dp_mst_atomic_check() * drm_dp_atomic_find_time_slots() * drm_dp_atomic_release_time_slots() * * Returns: * - 0 if the new state is valid * - %-ENOSPC, if the new state is invalid, because of BW limitation * @failing_port is set to: * * - The non-root port where a BW limit check failed * with all the ports downstream of @failing_port passing * the BW limit check. * The returned port pointer is valid until at least * one payload downstream of it exists. * - %NULL if the BW limit check failed at the root port * with all the ports downstream of the root port passing * the BW limit check. * * - %-EINVAL, if the new state is invalid, because the root port has * too many payloads. */ int drm_dp_mst_atomic_check_mgr(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr, struct drm_dp_mst_topology_state *mst_state, struct drm_dp_mst_port **failing_port) { int ret; *failing_port = NULL; if (!mgr->mst_state) return 0; mutex_lock(&mgr->lock); ret = drm_dp_mst_atomic_check_mstb_bw_limit(mgr->mst_primary, mst_state, failing_port); mutex_unlock(&mgr->lock); if (ret < 0) return ret; return drm_dp_mst_atomic_check_payload_alloc_limits(mgr, mst_state); } EXPORT_SYMBOL(drm_dp_mst_atomic_check_mgr); /** * drm_dp_mst_atomic_check - Check that the new state of an MST topology in an * atomic update is valid * @state: Pointer to the new &struct drm_dp_mst_topology_state * * Checks the given topology state for an atomic update to ensure that it's * valid, calling drm_dp_mst_atomic_check_mgr() for all MST manager in the * atomic state. This includes checking whether there's enough bandwidth to * support the new timeslot allocations in the atomic update. * * Any atomic drivers supporting DP MST must make sure to call this after * checking the rest of their state in their * &drm_mode_config_funcs.atomic_check() callback. * * See also: * drm_dp_mst_atomic_check_mgr() * drm_dp_atomic_find_time_slots() * drm_dp_atomic_release_time_slots() * * Returns: * * 0 if the new state is valid, negative error code otherwise. */ int drm_dp_mst_atomic_check(struct drm_atomic_state *state) { struct drm_dp_mst_topology_mgr *mgr; struct drm_dp_mst_topology_state *mst_state; int i, ret = 0; for_each_new_mst_mgr_in_state(state, mgr, mst_state, i) { struct drm_dp_mst_port *tmp_port; ret = drm_dp_mst_atomic_check_mgr(state, mgr, mst_state, &tmp_port); if (ret) break; } return ret; } EXPORT_SYMBOL(drm_dp_mst_atomic_check); const struct drm_private_state_funcs drm_dp_mst_topology_state_funcs = { .atomic_duplicate_state = drm_dp_mst_duplicate_state, .atomic_destroy_state = drm_dp_mst_destroy_state, }; EXPORT_SYMBOL(drm_dp_mst_topology_state_funcs); /** * drm_atomic_get_mst_topology_state: get MST topology state * @state: global atomic state * @mgr: MST topology manager, also the private object in this case * * This function wraps drm_atomic_get_priv_obj_state() passing in the MST atomic * state vtable so that the private object state returned is that of a MST * topology object. * * RETURNS: * * The MST topology state or error pointer. */ struct drm_dp_mst_topology_state *drm_atomic_get_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) { return to_dp_mst_topology_state(drm_atomic_get_private_obj_state(state, &mgr->base)); } EXPORT_SYMBOL(drm_atomic_get_mst_topology_state); /** * drm_atomic_get_old_mst_topology_state: get old MST topology state in atomic state, if any * @state: global atomic state * @mgr: MST topology manager, also the private object in this case * * This function wraps drm_atomic_get_old_private_obj_state() passing in the MST atomic * state vtable so that the private object state returned is that of a MST * topology object. * * Returns: * * The old MST topology state, or NULL if there's no topology state for this MST mgr * in the global atomic state */ struct drm_dp_mst_topology_state * drm_atomic_get_old_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) { struct drm_private_state *old_priv_state = drm_atomic_get_old_private_obj_state(state, &mgr->base); return old_priv_state ? to_dp_mst_topology_state(old_priv_state) : NULL; } EXPORT_SYMBOL(drm_atomic_get_old_mst_topology_state); /** * drm_atomic_get_new_mst_topology_state: get new MST topology state in atomic state, if any * @state: global atomic state * @mgr: MST topology manager, also the private object in this case * * This function wraps drm_atomic_get_new_private_obj_state() passing in the MST atomic * state vtable so that the private object state returned is that of a MST * topology object. * * Returns: * * The new MST topology state, or NULL if there's no topology state for this MST mgr * in the global atomic state */ struct drm_dp_mst_topology_state * drm_atomic_get_new_mst_topology_state(struct drm_atomic_state *state, struct drm_dp_mst_topology_mgr *mgr) { struct drm_private_state *new_priv_state = drm_atomic_get_new_private_obj_state(state, &mgr->base); return new_priv_state ? to_dp_mst_topology_state(new_priv_state) : NULL; } EXPORT_SYMBOL(drm_atomic_get_new_mst_topology_state); /** * drm_dp_mst_topology_mgr_init - initialise a topology manager * @mgr: manager struct to initialise * @dev: device providing this structure - for i2c addition. * @aux: DP helper aux channel to talk to this device * @max_dpcd_transaction_bytes: hw specific DPCD transaction limit * @max_payloads: maximum number of payloads this GPU can source * @conn_base_id: the connector object ID the MST device is connected to. * * Return 0 for success, or negative error code on failure */ int drm_dp_mst_topology_mgr_init(struct drm_dp_mst_topology_mgr *mgr, struct drm_device *dev, struct drm_dp_aux *aux, int max_dpcd_transaction_bytes, int max_payloads, int conn_base_id) { struct drm_dp_mst_topology_state *mst_state; mutex_init(&mgr->lock); mutex_init(&mgr->qlock); mutex_init(&mgr->delayed_destroy_lock); mutex_init(&mgr->up_req_lock); mutex_init(&mgr->probe_lock); #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) mutex_init(&mgr->topology_ref_history_lock); stack_depot_init(); #endif INIT_LIST_HEAD(&mgr->tx_msg_downq); INIT_LIST_HEAD(&mgr->destroy_port_list); INIT_LIST_HEAD(&mgr->destroy_branch_device_list); INIT_LIST_HEAD(&mgr->up_req_list); /* * delayed_destroy_work will be queued on a dedicated WQ, so that any * requeuing will be also flushed when deiniting the topology manager. */ mgr->delayed_destroy_wq = alloc_ordered_workqueue("drm_dp_mst_wq", 0); if (mgr->delayed_destroy_wq == NULL) return -ENOMEM; INIT_WORK(&mgr->work, drm_dp_mst_link_probe_work); INIT_WORK(&mgr->tx_work, drm_dp_tx_work); INIT_WORK(&mgr->delayed_destroy_work, drm_dp_delayed_destroy_work); INIT_WORK(&mgr->up_req_work, drm_dp_mst_up_req_work); init_waitqueue_head(&mgr->tx_waitq); mgr->dev = dev; mgr->aux = aux; mgr->max_dpcd_transaction_bytes = max_dpcd_transaction_bytes; mgr->max_payloads = max_payloads; mgr->conn_base_id = conn_base_id; mst_state = kzalloc(sizeof(*mst_state), GFP_KERNEL); if (mst_state == NULL) return -ENOMEM; mst_state->total_avail_slots = 63; mst_state->start_slot = 1; mst_state->mgr = mgr; INIT_LIST_HEAD(&mst_state->payloads); drm_atomic_private_obj_init(dev, &mgr->base, &mst_state->base, &drm_dp_mst_topology_state_funcs); return 0; } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_init); /** * drm_dp_mst_topology_mgr_destroy() - destroy topology manager. * @mgr: manager to destroy */ void drm_dp_mst_topology_mgr_destroy(struct drm_dp_mst_topology_mgr *mgr) { drm_dp_mst_topology_mgr_set_mst(mgr, false); flush_work(&mgr->work); /* The following will also drain any requeued work on the WQ. */ if (mgr->delayed_destroy_wq) { destroy_workqueue(mgr->delayed_destroy_wq); mgr->delayed_destroy_wq = NULL; } mgr->dev = NULL; mgr->aux = NULL; drm_atomic_private_obj_fini(&mgr->base); mgr->funcs = NULL; mutex_destroy(&mgr->delayed_destroy_lock); mutex_destroy(&mgr->qlock); mutex_destroy(&mgr->lock); mutex_destroy(&mgr->up_req_lock); mutex_destroy(&mgr->probe_lock); #if IS_ENABLED(CONFIG_DRM_DEBUG_DP_MST_TOPOLOGY_REFS) mutex_destroy(&mgr->topology_ref_history_lock); #endif } EXPORT_SYMBOL(drm_dp_mst_topology_mgr_destroy); static bool remote_i2c_read_ok(const struct i2c_msg msgs[], int num) { int i; if (num - 1 > DP_REMOTE_I2C_READ_MAX_TRANSACTIONS) return false; for (i = 0; i < num - 1; i++) { if (msgs[i].flags & I2C_M_RD || msgs[i].len > 0xff) return false; } return msgs[num - 1].flags & I2C_M_RD && msgs[num - 1].len <= 0xff; } static bool remote_i2c_write_ok(const struct i2c_msg msgs[], int num) { int i; for (i = 0; i < num - 1; i++) { if (msgs[i].flags & I2C_M_RD || !(msgs[i].flags & I2C_M_STOP) || msgs[i].len > 0xff) return false; } return !(msgs[num - 1].flags & I2C_M_RD) && msgs[num - 1].len <= 0xff; } static int drm_dp_mst_i2c_read(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *port, struct i2c_msg *msgs, int num) { struct drm_dp_mst_topology_mgr *mgr = port->mgr; unsigned int i; struct drm_dp_sideband_msg_req_body msg; struct drm_dp_sideband_msg_tx *txmsg = NULL; int ret; memset(&msg, 0, sizeof(msg)); msg.req_type = DP_REMOTE_I2C_READ; msg.u.i2c_read.num_transactions = num - 1; msg.u.i2c_read.port_number = port->port_num; for (i = 0; i < num - 1; i++) { msg.u.i2c_read.transactions[i].i2c_dev_id = msgs[i].addr; msg.u.i2c_read.transactions[i].num_bytes = msgs[i].len; msg.u.i2c_read.transactions[i].bytes = msgs[i].buf; msg.u.i2c_read.transactions[i].no_stop_bit = !(msgs[i].flags & I2C_M_STOP); } msg.u.i2c_read.read_i2c_device_id = msgs[num - 1].addr; msg.u.i2c_read.num_bytes_read = msgs[num - 1].len; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { ret = -ENOMEM; goto out; } txmsg->dst = mstb; drm_dp_encode_sideband_req(&msg, txmsg); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0) { if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { ret = -EREMOTEIO; goto out; } if (txmsg->reply.u.remote_i2c_read_ack.num_bytes != msgs[num - 1].len) { ret = -EIO; goto out; } memcpy(msgs[num - 1].buf, txmsg->reply.u.remote_i2c_read_ack.bytes, msgs[num - 1].len); ret = num; } out: kfree(txmsg); return ret; } static int drm_dp_mst_i2c_write(struct drm_dp_mst_branch *mstb, struct drm_dp_mst_port *port, struct i2c_msg *msgs, int num) { struct drm_dp_mst_topology_mgr *mgr = port->mgr; unsigned int i; struct drm_dp_sideband_msg_req_body msg; struct drm_dp_sideband_msg_tx *txmsg = NULL; int ret; txmsg = kzalloc(sizeof(*txmsg), GFP_KERNEL); if (!txmsg) { ret = -ENOMEM; goto out; } for (i = 0; i < num; i++) { memset(&msg, 0, sizeof(msg)); msg.req_type = DP_REMOTE_I2C_WRITE; msg.u.i2c_write.port_number = port->port_num; msg.u.i2c_write.write_i2c_device_id = msgs[i].addr; msg.u.i2c_write.num_bytes = msgs[i].len; msg.u.i2c_write.bytes = msgs[i].buf; memset(txmsg, 0, sizeof(*txmsg)); txmsg->dst = mstb; drm_dp_encode_sideband_req(&msg, txmsg); drm_dp_queue_down_tx(mgr, txmsg); ret = drm_dp_mst_wait_tx_reply(mstb, txmsg); if (ret > 0) { if (txmsg->reply.reply_type == DP_SIDEBAND_REPLY_NAK) { ret = -EREMOTEIO; goto out; } } else { goto out; } } ret = num; out: kfree(txmsg); return ret; } /* I2C device */ static int drm_dp_mst_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { struct drm_dp_aux *aux = adapter->algo_data; struct drm_dp_mst_port *port = container_of(aux, struct drm_dp_mst_port, aux); struct drm_dp_mst_branch *mstb; struct drm_dp_mst_topology_mgr *mgr = port->mgr; int ret; mstb = drm_dp_mst_topology_get_mstb_validated(mgr, port->parent); if (!mstb) return -EREMOTEIO; if (remote_i2c_read_ok(msgs, num)) { ret = drm_dp_mst_i2c_read(mstb, port, msgs, num); } else if (remote_i2c_write_ok(msgs, num)) { ret = drm_dp_mst_i2c_write(mstb, port, msgs, num); } else { drm_dbg_kms(mgr->dev, "Unsupported I2C transaction for MST device\n"); ret = -EIO; } drm_dp_mst_topology_put_mstb(mstb); return ret; } static u32 drm_dp_mst_i2c_functionality(struct i2c_adapter *adapter) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL | I2C_FUNC_10BIT_ADDR; } static const struct i2c_algorithm drm_dp_mst_i2c_algo = { .functionality = drm_dp_mst_i2c_functionality, .master_xfer = drm_dp_mst_i2c_xfer, }; /** * drm_dp_mst_register_i2c_bus() - register an I2C adapter for I2C-over-AUX * @port: The port to add the I2C bus on * * Returns 0 on success or a negative error code on failure. */ static int drm_dp_mst_register_i2c_bus(struct drm_dp_mst_port *port) { struct drm_dp_aux *aux = &port->aux; struct device *parent_dev = port->mgr->dev->dev; aux->ddc.algo = &drm_dp_mst_i2c_algo; aux->ddc.algo_data = aux; aux->ddc.retries = 3; aux->ddc.owner = THIS_MODULE; /* FIXME: set the kdev of the port's connector as parent */ aux->ddc.dev.parent = parent_dev; aux->ddc.dev.of_node = parent_dev->of_node; strscpy(aux->ddc.name, aux->name ? aux->name : dev_name(parent_dev), sizeof(aux->ddc.name)); return i2c_add_adapter(&aux->ddc); } /** * drm_dp_mst_unregister_i2c_bus() - unregister an I2C-over-AUX adapter * @port: The port to remove the I2C bus from */ static void drm_dp_mst_unregister_i2c_bus(struct drm_dp_mst_port *port) { i2c_del_adapter(&port->aux.ddc); } /** * drm_dp_mst_is_virtual_dpcd() - Is the given port a virtual DP Peer Device * @port: The port to check * * A single physical MST hub object can be represented in the topology * by multiple branches, with virtual ports between those branches. * * As of DP1.4, An MST hub with internal (virtual) ports must expose * certain DPCD registers over those ports. See sections 2.6.1.1.1 * and 2.6.1.1.2 of Display Port specification v1.4 for details. * * May acquire mgr->lock * * Returns: * true if the port is a virtual DP peer device, false otherwise */ static bool drm_dp_mst_is_virtual_dpcd(struct drm_dp_mst_port *port) { struct drm_dp_mst_port *downstream_port; if (!port || port->dpcd_rev < DP_DPCD_REV_14) return false; /* Virtual DP Sink (Internal Display Panel) */ if (drm_dp_mst_port_is_logical(port)) return true; /* DP-to-HDMI Protocol Converter */ if (port->pdt == DP_PEER_DEVICE_DP_LEGACY_CONV && !port->mcs && port->ldps) return true; /* DP-to-DP */ mutex_lock(&port->mgr->lock); if (port->pdt == DP_PEER_DEVICE_MST_BRANCHING && port->mstb && port->mstb->num_ports == 2) { list_for_each_entry(downstream_port, &port->mstb->ports, next) { if (downstream_port->pdt == DP_PEER_DEVICE_SST_SINK && !downstream_port->input) { mutex_unlock(&port->mgr->lock); return true; } } } mutex_unlock(&port->mgr->lock); return false; } /** * drm_dp_mst_aux_for_parent() - Get the AUX device for an MST port's parent * @port: MST port whose parent's AUX device is returned * * Return the AUX device for @port's parent or NULL if port's parent is the * root port. */ struct drm_dp_aux *drm_dp_mst_aux_for_parent(struct drm_dp_mst_port *port) { if (!port->parent || !port->parent->port_parent) return NULL; return &port->parent->port_parent->aux; } EXPORT_SYMBOL(drm_dp_mst_aux_for_parent); /** * drm_dp_mst_dsc_aux_for_port() - Find the correct aux for DSC * @port: The port to check. A leaf of the MST tree with an attached display. * * Depending on the situation, DSC may be enabled via the endpoint aux, * the immediately upstream aux, or the connector's physical aux. * * This is both the correct aux to read DSC_CAPABILITY and the * correct aux to write DSC_ENABLED. * * This operation can be expensive (up to four aux reads), so * the caller should cache the return. * * Returns: * NULL if DSC cannot be enabled on this port, otherwise the aux device */ struct drm_dp_aux *drm_dp_mst_dsc_aux_for_port(struct drm_dp_mst_port *port) { struct drm_dp_mst_port *immediate_upstream_port; struct drm_dp_aux *immediate_upstream_aux; struct drm_dp_mst_port *fec_port; struct drm_dp_desc desc = {}; u8 endpoint_fec; u8 endpoint_dsc; if (!port) return NULL; if (port->parent->port_parent) immediate_upstream_port = port->parent->port_parent; else immediate_upstream_port = NULL; fec_port = immediate_upstream_port; while (fec_port) { /* * Each physical link (i.e. not a virtual port) between the * output and the primary device must support FEC */ if (!drm_dp_mst_is_virtual_dpcd(fec_port) && !fec_port->fec_capable) return NULL; fec_port = fec_port->parent->port_parent; } /* DP-to-DP peer device */ if (drm_dp_mst_is_virtual_dpcd(immediate_upstream_port)) { u8 upstream_dsc; if (drm_dp_dpcd_read(&port->aux, DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1) return NULL; if (drm_dp_dpcd_read(&port->aux, DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1) return NULL; if (drm_dp_dpcd_read(&immediate_upstream_port->aux, DP_DSC_SUPPORT, &upstream_dsc, 1) != 1) return NULL; /* Enpoint decompression with DP-to-DP peer device */ if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) && (endpoint_fec & DP_FEC_CAPABLE) && (upstream_dsc & DP_DSC_PASSTHROUGH_IS_SUPPORTED)) { port->passthrough_aux = &immediate_upstream_port->aux; return &port->aux; } /* Virtual DPCD decompression with DP-to-DP peer device */ return &immediate_upstream_port->aux; } /* Virtual DPCD decompression with DP-to-HDMI or Virtual DP Sink */ if (drm_dp_mst_is_virtual_dpcd(port)) return &port->aux; /* * Synaptics quirk * Applies to ports for which: * - Physical aux has Synaptics OUI * - DPv1.4 or higher * - Port is on primary branch device * - Not a VGA adapter (DP_DWN_STRM_PORT_TYPE_ANALOG) */ if (immediate_upstream_port) immediate_upstream_aux = &immediate_upstream_port->aux; else immediate_upstream_aux = port->mgr->aux; if (drm_dp_read_desc(immediate_upstream_aux, &desc, true)) return NULL; if (drm_dp_has_quirk(&desc, DP_DPCD_QUIRK_DSC_WITHOUT_VIRTUAL_DPCD)) { u8 dpcd_ext[DP_RECEIVER_CAP_SIZE]; if (drm_dp_read_dpcd_caps(immediate_upstream_aux, dpcd_ext) < 0) return NULL; if (dpcd_ext[DP_DPCD_REV] >= DP_DPCD_REV_14 && ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_PRESENT) && ((dpcd_ext[DP_DOWNSTREAMPORT_PRESENT] & DP_DWN_STRM_PORT_TYPE_MASK) != DP_DWN_STRM_PORT_TYPE_ANALOG))) return immediate_upstream_aux; } /* * The check below verifies if the MST sink * connected to the GPU is capable of DSC - * therefore the endpoint needs to be * both DSC and FEC capable. */ if (drm_dp_dpcd_read(&port->aux, DP_DSC_SUPPORT, &endpoint_dsc, 1) != 1) return NULL; if (drm_dp_dpcd_read(&port->aux, DP_FEC_CAPABILITY, &endpoint_fec, 1) != 1) return NULL; if ((endpoint_dsc & DP_DSC_DECOMPRESSION_IS_SUPPORTED) && (endpoint_fec & DP_FEC_CAPABLE)) return &port->aux; return NULL; } EXPORT_SYMBOL(drm_dp_mst_dsc_aux_for_port);
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with Cregit http://github.com/cregit/cregit
Version 2.0-RC1