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Release 4.7 drivers/net/wireless/mediatek/mt7601u/dma.c

/*
 * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2
 * as published by the Free Software Foundation
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 */

#include "mt7601u.h"
#include "dma.h"
#include "usb.h"
#include "trace.h"

static int mt7601u_submit_rx_buf(struct mt7601u_dev *dev,
				 struct mt7601u_dma_buf_rx *e, gfp_t gfp);


static unsigned int ieee80211_get_hdrlen_from_buf(const u8 *data, unsigned len) { const struct ieee80211_hdr *hdr = (const struct ieee80211_hdr *)data; unsigned int hdrlen; if (unlikely(len < 10)) return 0; hdrlen = ieee80211_hdrlen(hdr->frame_control); if (unlikely(hdrlen > len)) return 0; return hdrlen; }

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static struct sk_buff * mt7601u_rx_skb_from_seg(struct mt7601u_dev *dev, struct mt7601u_rxwi *rxwi, void *data, u32 seg_len, u32 truesize, struct page *p) { struct sk_buff *skb; u32 true_len, hdr_len = 0, copy, frag; skb = alloc_skb(p ? 128 : seg_len, GFP_ATOMIC); if (!skb) return NULL; true_len = mt76_mac_process_rx(dev, skb, data, rxwi); if (!true_len || true_len > seg_len) goto bad_frame; hdr_len = ieee80211_get_hdrlen_from_buf(data, true_len); if (!hdr_len) goto bad_frame; if (rxwi->rxinfo & cpu_to_le32(MT_RXINFO_L2PAD)) { memcpy(skb_put(skb, hdr_len), data, hdr_len); data += hdr_len + 2; true_len -= hdr_len; hdr_len = 0; } /* If not doing paged RX allocated skb will always have enough space */ copy = (true_len <= skb_tailroom(skb)) ? true_len : hdr_len + 8; frag = true_len - copy; memcpy(skb_put(skb, copy), data, copy); data += copy; if (frag) { skb_add_rx_frag(skb, 0, p, data - page_address(p), frag, truesize); get_page(p); } return skb; bad_frame: dev_err_ratelimited(dev->dev, "Error: incorrect frame len:%u hdr:%u\n", true_len, hdr_len); dev_kfree_skb(skb); return NULL; }

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static void mt7601u_rx_process_seg(struct mt7601u_dev *dev, u8 *data, u32 seg_len, struct page *p) { struct sk_buff *skb; struct mt7601u_rxwi *rxwi; u32 fce_info, truesize = seg_len; /* DMA_INFO field at the beginning of the segment contains only some of * the information, we need to read the FCE descriptor from the end. */ fce_info = get_unaligned_le32(data + seg_len - MT_FCE_INFO_LEN); seg_len -= MT_FCE_INFO_LEN; data += MT_DMA_HDR_LEN; seg_len -= MT_DMA_HDR_LEN; rxwi = (struct mt7601u_rxwi *) data; data += sizeof(struct mt7601u_rxwi); seg_len -= sizeof(struct mt7601u_rxwi); if (unlikely(rxwi->zero[0] || rxwi->zero[1] || rxwi->zero[2])) dev_err_once(dev->dev, "Error: RXWI zero fields are set\n"); if (unlikely(MT76_GET(MT_RXD_INFO_TYPE, fce_info))) dev_err_once(dev->dev, "Error: RX path seen a non-pkt urb\n"); trace_mt_rx(dev, rxwi, fce_info); skb = mt7601u_rx_skb_from_seg(dev, rxwi, data, seg_len, truesize, p); if (!skb) return; spin_lock(&dev->mac_lock); ieee80211_rx(dev->hw, skb); spin_unlock(&dev->mac_lock); }

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static u16 mt7601u_rx_next_seg_len(u8 *data, u32 data_len) { u32 min_seg_len = MT_DMA_HDR_LEN + MT_RX_INFO_LEN + sizeof(struct mt7601u_rxwi) + MT_FCE_INFO_LEN; u16 dma_len = get_unaligned_le16(data); if (data_len < min_seg_len || WARN_ON(!dma_len) || WARN_ON(dma_len + MT_DMA_HDRS > data_len) || WARN_ON(dma_len & 0x3)) return 0; return MT_DMA_HDRS + dma_len; }

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static void mt7601u_rx_process_entry(struct mt7601u_dev *dev, struct mt7601u_dma_buf_rx *e) { u32 seg_len, data_len = e->urb->actual_length; u8 *data = page_address(e->p); struct page *new_p = NULL; int cnt = 0; if (!test_bit(MT7601U_STATE_INITIALIZED, &dev->state)) return; /* Copy if there is very little data in the buffer. */ if (data_len > 512) new_p = dev_alloc_pages(MT_RX_ORDER); while ((seg_len = mt7601u_rx_next_seg_len(data, data_len))) { mt7601u_rx_process_seg(dev, data, seg_len, new_p ? e->p : NULL); data_len -= seg_len; data += seg_len; cnt++; } if (cnt > 1) trace_mt_rx_dma_aggr(dev, cnt, !!new_p); if (new_p) { /* we have one extra ref from the allocator */ __free_pages(e->p, MT_RX_ORDER); e->p = new_p; } }

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static struct mt7601u_dma_buf_rx * mt7601u_rx_get_pending_entry(struct mt7601u_dev *dev) { struct mt7601u_rx_queue *q = &dev->rx_q; struct mt7601u_dma_buf_rx *buf = NULL; unsigned long flags; spin_lock_irqsave(&dev->rx_lock, flags); if (!q->pending) goto out; buf = &q->e[q->start]; q->pending--; q->start = (q->start + 1) % q->entries; out: spin_unlock_irqrestore(&dev->rx_lock, flags); return buf; }

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static void mt7601u_complete_rx(struct urb *urb) { struct mt7601u_dev *dev = urb->context; struct mt7601u_rx_queue *q = &dev->rx_q; unsigned long flags; spin_lock_irqsave(&dev->rx_lock, flags); if (mt7601u_urb_has_error(urb)) dev_err(dev->dev, "Error: RX urb failed:%d\n", urb->status); if (WARN_ONCE(q->e[q->end].urb != urb, "RX urb mismatch")) goto out; q->end = (q->end + 1) % q->entries; q->pending++; tasklet_schedule(&dev->rx_tasklet); out: spin_unlock_irqrestore(&dev->rx_lock, flags); }

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static void mt7601u_rx_tasklet(unsigned long data) { struct mt7601u_dev *dev = (struct mt7601u_dev *) data; struct mt7601u_dma_buf_rx *e; while ((e = mt7601u_rx_get_pending_entry(dev))) { if (e->urb->status) continue; mt7601u_rx_process_entry(dev, e); mt7601u_submit_rx_buf(dev, e, GFP_ATOMIC); } }

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static void mt7601u_complete_tx(struct urb *urb) { struct mt7601u_tx_queue *q = urb->context; struct mt7601u_dev *dev = q->dev; struct sk_buff *skb; unsigned long flags; spin_lock_irqsave(&dev->tx_lock, flags); if (mt7601u_urb_has_error(urb)) dev_err(dev->dev, "Error: TX urb failed:%d\n", urb->status); if (WARN_ONCE(q->e[q->start].urb != urb, "TX urb mismatch")) goto out; skb = q->e[q->start].skb; trace_mt_tx_dma_done(dev, skb); __skb_queue_tail(&dev->tx_skb_done, skb); tasklet_schedule(&dev->tx_tasklet); if (q->used == q->entries - q->entries / 8) ieee80211_wake_queue(dev->hw, skb_get_queue_mapping(skb)); q->start = (q->start + 1) % q->entries; q->used--; out: spin_unlock_irqrestore(&dev->tx_lock, flags); }

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static void mt7601u_tx_tasklet(unsigned long data) { struct mt7601u_dev *dev = (struct mt7601u_dev *) data; struct sk_buff_head skbs; unsigned long flags; __skb_queue_head_init(&skbs); spin_lock_irqsave(&dev->tx_lock, flags); set_bit(MT7601U_STATE_MORE_STATS, &dev->state); if (!test_and_set_bit(MT7601U_STATE_READING_STATS, &dev->state)) queue_delayed_work(dev->stat_wq, &dev->stat_work, msecs_to_jiffies(10)); skb_queue_splice_init(&dev->tx_skb_done, &skbs); spin_unlock_irqrestore(&dev->tx_lock, flags); while (!skb_queue_empty(&skbs)) { struct sk_buff *skb = __skb_dequeue(&skbs); mt7601u_tx_status(dev, skb); } }

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static int mt7601u_dma_submit_tx(struct mt7601u_dev *dev, struct sk_buff *skb, u8 ep) { struct usb_device *usb_dev = mt7601u_to_usb_dev(dev); unsigned snd_pipe = usb_sndbulkpipe(usb_dev, dev->out_eps[ep]); struct mt7601u_dma_buf_tx *e; struct mt7601u_tx_queue *q = &dev->tx_q[ep]; unsigned long flags; int ret; spin_lock_irqsave(&dev->tx_lock, flags); if (WARN_ON(q->entries <= q->used)) { ret = -ENOSPC; goto out; } e = &q->e[q->end]; e->skb = skb; usb_fill_bulk_urb(e->urb, usb_dev, snd_pipe, skb->data, skb->len, mt7601u_complete_tx, q); ret = usb_submit_urb(e->urb, GFP_ATOMIC); if (ret) { /* Special-handle ENODEV from TX urb submission because it will * often be the first ENODEV we see after device is removed. */ if (ret == -ENODEV) set_bit(MT7601U_STATE_REMOVED, &dev->state); else dev_err(dev->dev, "Error: TX urb submit failed:%d\n", ret); goto out; } q->end = (q->end + 1) % q->entries; q->used++; if (q->used >= q->entries) ieee80211_stop_queue(dev->hw, skb_get_queue_mapping(skb)); out: spin_unlock_irqrestore(&dev->tx_lock, flags); return ret; }

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/* Map hardware Q to USB endpoint number */
static u8 q2ep(u8 qid) { /* TODO: take management packets to queue 5 */ return qid + 1; }

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/* Map USB endpoint number to Q id in the DMA engine */
static enum mt76_qsel ep2dmaq(u8 ep) { if (ep == 5) return MT_QSEL_MGMT; return MT_QSEL_EDCA; }

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int mt7601u_dma_enqueue_tx(struct mt7601u_dev *dev, struct sk_buff *skb, struct mt76_wcid *wcid, int hw_q) { u8 ep = q2ep(hw_q); u32 dma_flags; int ret; dma_flags = MT_TXD_PKT_INFO_80211; if (wcid->hw_key_idx == 0xff) dma_flags |= MT_TXD_PKT_INFO_WIV; ret = mt7601u_dma_skb_wrap_pkt(skb, ep2dmaq(ep), dma_flags); if (ret) return ret; ret = mt7601u_dma_submit_tx(dev, skb, ep); if (ret) { ieee80211_free_txskb(dev->hw, skb); return ret; } return 0; }

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static void mt7601u_kill_rx(struct mt7601u_dev *dev) { int i; unsigned long flags; spin_lock_irqsave(&dev->rx_lock, flags); for (i = 0; i < dev->rx_q.entries; i++) { int next = dev->rx_q.end; spin_unlock_irqrestore(&dev->rx_lock, flags); usb_poison_urb(dev->rx_q.e[next].urb); spin_lock_irqsave(&dev->rx_lock, flags); } spin_unlock_irqrestore(&dev->rx_lock, flags); }

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static int mt7601u_submit_rx_buf(struct mt7601u_dev *dev, struct mt7601u_dma_buf_rx *e, gfp_t gfp) { struct usb_device *usb_dev = mt7601u_to_usb_dev(dev); u8 *buf = page_address(e->p); unsigned pipe; int ret; pipe = usb_rcvbulkpipe(usb_dev, dev->in_eps[MT_EP_IN_PKT_RX]); usb_fill_bulk_urb(e->urb, usb_dev, pipe, buf, MT_RX_URB_SIZE, mt7601u_complete_rx, dev); trace_mt_submit_urb(dev, e->urb); ret = usb_submit_urb(e->urb, gfp); if (ret) dev_err(dev->dev, "Error: submit RX URB failed:%d\n", ret); return ret; }

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static int mt7601u_submit_rx(struct mt7601u_dev *dev) { int i, ret; for (i = 0; i < dev->rx_q.entries; i++) { ret = mt7601u_submit_rx_buf(dev, &dev->rx_q.e[i], GFP_KERNEL); if (ret) return ret; } return 0; }

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static void mt7601u_free_rx(struct mt7601u_dev *dev) { int i; for (i = 0; i < dev->rx_q.entries; i++) { __free_pages(dev->rx_q.e[i].p, MT_RX_ORDER); usb_free_urb(dev->rx_q.e[i].urb); } }

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static int mt7601u_alloc_rx(struct mt7601u_dev *dev) { int i; memset(&dev->rx_q, 0, sizeof(dev->rx_q)); dev->rx_q.dev = dev; dev->rx_q.entries = N_RX_ENTRIES; for (i = 0; i < N_RX_ENTRIES; i++) { dev->rx_q.e[i].urb = usb_alloc_urb(0, GFP_KERNEL); dev->rx_q.e[i].p = dev_alloc_pages(MT_RX_ORDER); if (!dev->rx_q.e[i].urb || !dev->rx_q.e[i].p) return -ENOMEM; } return 0; }

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static void mt7601u_free_tx_queue(struct mt7601u_tx_queue *q) { int i; WARN_ON(q->used); for (i = 0; i < q->entries; i++) { usb_poison_urb(q->e[i].urb); usb_free_urb(q->e[i].urb); } }

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static void mt7601u_free_tx(struct mt7601u_dev *dev) { int i; for (i = 0; i < __MT_EP_OUT_MAX; i++) mt7601u_free_tx_queue(&dev->tx_q[i]); }

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static int mt7601u_alloc_tx_queue(struct mt7601u_dev *dev, struct mt7601u_tx_queue *q) { int i; q->dev = dev; q->entries = N_TX_ENTRIES; for (i = 0; i < N_TX_ENTRIES; i++) { q->e[i].urb = usb_alloc_urb(0, GFP_KERNEL); if (!q->e[i].urb) return -ENOMEM; } return 0; }

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static int mt7601u_alloc_tx(struct mt7601u_dev *dev) { int i; dev->tx_q = devm_kcalloc(dev->dev, __MT_EP_OUT_MAX, sizeof(*dev->tx_q), GFP_KERNEL); for (i = 0; i < __MT_EP_OUT_MAX; i++) if (mt7601u_alloc_tx_queue(dev, &dev->tx_q[i])) return -ENOMEM; return 0; }

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int mt7601u_dma_init(struct mt7601u_dev *dev) { int ret = -ENOMEM; tasklet_init(&dev->tx_tasklet, mt7601u_tx_tasklet, (unsigned long) dev); tasklet_init(&dev->rx_tasklet, mt7601u_rx_tasklet, (unsigned long) dev); ret = mt7601u_alloc_tx(dev); if (ret) goto err; ret = mt7601u_alloc_rx(dev); if (ret) goto err; ret = mt7601u_submit_rx(dev); if (ret) goto err; return 0; err: mt7601u_dma_cleanup(dev); return ret; }

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void mt7601u_dma_cleanup(struct mt7601u_dev *dev) { mt7601u_kill_rx(dev); tasklet_kill(&dev->rx_tasklet); mt7601u_free_rx(dev); mt7601u_free_tx(dev); tasklet_kill(&dev->tx_tasklet); }

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