| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Ashwin Chaugule | 2868 | 57.81% | 5 | 15.62% |
| Prashanth Prakash | 1287 | 25.94% | 13 | 40.62% |
| George Cherian | 554 | 11.17% | 3 | 9.38% |
| Srinivas Pandruvada | 165 | 3.33% | 3 | 9.38% |
| Hoan Tran | 46 | 0.93% | 2 | 6.25% |
| Rafael J. Wysocki | 25 | 0.50% | 1 | 3.12% |
| Dan Carpenter | 8 | 0.16% | 2 | 6.25% |
| Sebastian Andrzej Siewior | 6 | 0.12% | 1 | 3.12% |
| Gustavo A. R. Silva | 1 | 0.02% | 1 | 3.12% |
| Stephen Boyd | 1 | 0.02% | 1 | 3.12% |
| Total | 4961 | 32 |
/* * CPPC (Collaborative Processor Performance Control) methods used by CPUfreq drivers. * * (C) Copyright 2014, 2015 Linaro Ltd. * Author: Ashwin Chaugule <ashwin.chaugule@linaro.org> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; version 2 * of the License. * * CPPC describes a few methods for controlling CPU performance using * information from a per CPU table called CPC. This table is described in * the ACPI v5.0+ specification. The table consists of a list of * registers which may be memory mapped or hardware registers and also may * include some static integer values. * * CPU performance is on an abstract continuous scale as against a discretized * P-state scale which is tied to CPU frequency only. In brief, the basic * operation involves: * * - OS makes a CPU performance request. (Can provide min and max bounds) * * - Platform (such as BMC) is free to optimize request within requested bounds * depending on power/thermal budgets etc. * * - Platform conveys its decision back to OS * * The communication between OS and platform occurs through another medium * called (PCC) Platform Communication Channel. This is a generic mailbox like * mechanism which includes doorbell semantics to indicate register updates. * See drivers/mailbox/pcc.c for details on PCC. * * Finer details about the PCC and CPPC spec are available in the ACPI v5.1 and * above specifications. */ #define pr_fmt(fmt) "ACPI CPPC: " fmt #include <linux/cpufreq.h> #include <linux/delay.h> #include <linux/iopoll.h> #include <linux/ktime.h> #include <linux/rwsem.h> #include <linux/wait.h> #include <acpi/cppc_acpi.h> struct cppc_pcc_data { struct mbox_chan *pcc_channel; void __iomem *pcc_comm_addr; bool pcc_channel_acquired; unsigned int deadline_us; unsigned int pcc_mpar, pcc_mrtt, pcc_nominal; bool pending_pcc_write_cmd; /* Any pending/batched PCC write cmds? */ bool platform_owns_pcc; /* Ownership of PCC subspace */ unsigned int pcc_write_cnt; /* Running count of PCC write commands */ /* * Lock to provide controlled access to the PCC channel. * * For performance critical usecases(currently cppc_set_perf) * We need to take read_lock and check if channel belongs to OSPM * before reading or writing to PCC subspace * We need to take write_lock before transferring the channel * ownership to the platform via a Doorbell * This allows us to batch a number of CPPC requests if they happen * to originate in about the same time * * For non-performance critical usecases(init) * Take write_lock for all purposes which gives exclusive access */ struct rw_semaphore pcc_lock; /* Wait queue for CPUs whose requests were batched */ wait_queue_head_t pcc_write_wait_q; ktime_t last_cmd_cmpl_time; ktime_t last_mpar_reset; int mpar_count; int refcount; }; /* Array to represent the PCC channel per subspace id */ static struct cppc_pcc_data *pcc_data[MAX_PCC_SUBSPACES]; /* The cpu_pcc_subspace_idx containsper CPU subspace id */ static DEFINE_PER_CPU(int, cpu_pcc_subspace_idx); /* * The cpc_desc structure contains the ACPI register details * as described in the per CPU _CPC tables. The details * include the type of register (e.g. PCC, System IO, FFH etc.) * and destination addresses which lets us READ/WRITE CPU performance * information using the appropriate I/O methods. */ static DEFINE_PER_CPU(struct cpc_desc *, cpc_desc_ptr); /* pcc mapped address + header size + offset within PCC subspace */ #define GET_PCC_VADDR(offs, pcc_ss_id) (pcc_data[pcc_ss_id]->pcc_comm_addr + \ 0x8 + (offs)) /* Check if a CPC register is in PCC */ #define CPC_IN_PCC(cpc) ((cpc)->type == ACPI_TYPE_BUFFER && \ (cpc)->cpc_entry.reg.space_id == \ ACPI_ADR_SPACE_PLATFORM_COMM) /* Evalutes to True if reg is a NULL register descriptor */ #define IS_NULL_REG(reg) ((reg)->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY && \ (reg)->address == 0 && \ (reg)->bit_width == 0 && \ (reg)->bit_offset == 0 && \ (reg)->access_width == 0) /* Evalutes to True if an optional cpc field is supported */ #define CPC_SUPPORTED(cpc) ((cpc)->type == ACPI_TYPE_INTEGER ? \ !!(cpc)->cpc_entry.int_value : \ !IS_NULL_REG(&(cpc)->cpc_entry.reg)) /* * Arbitrary Retries in case the remote processor is slow to respond * to PCC commands. Keeping it high enough to cover emulators where * the processors run painfully slow. */ #define NUM_RETRIES 500ULL struct cppc_attr { struct attribute attr; ssize_t (*show)(struct kobject *kobj, struct attribute *attr, char *buf); ssize_t (*store)(struct kobject *kobj, struct attribute *attr, const char *c, ssize_t count); }; #define define_one_cppc_ro(_name) \ static struct cppc_attr _name = \ __ATTR(_name, 0444, show_##_name, NULL) #define to_cpc_desc(a) container_of(a, struct cpc_desc, kobj) #define show_cppc_data(access_fn, struct_name, member_name) \ static ssize_t show_##member_name(struct kobject *kobj, \ struct attribute *attr, char *buf) \ { \ struct cpc_desc *cpc_ptr = to_cpc_desc(kobj); \ struct struct_name st_name = {0}; \ int ret; \ \ ret = access_fn(cpc_ptr->cpu_id, &st_name); \ if (ret) \ return ret; \ \ return scnprintf(buf, PAGE_SIZE, "%llu\n", \ (u64)st_name.member_name); \ } \ define_one_cppc_ro(member_name) show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, highest_perf); show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, lowest_perf); show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_perf); show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, lowest_nonlinear_perf); show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, lowest_freq); show_cppc_data(cppc_get_perf_caps, cppc_perf_caps, nominal_freq); show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, reference_perf); show_cppc_data(cppc_get_perf_ctrs, cppc_perf_fb_ctrs, wraparound_time); static ssize_t show_feedback_ctrs(struct kobject *kobj, struct attribute *attr, char *buf) { struct cpc_desc *cpc_ptr = to_cpc_desc(kobj); struct cppc_perf_fb_ctrs fb_ctrs = {0}; int ret; ret = cppc_get_perf_ctrs(cpc_ptr->cpu_id, &fb_ctrs); if (ret) return ret; return scnprintf(buf, PAGE_SIZE, "ref:%llu del:%llu\n", fb_ctrs.reference, fb_ctrs.delivered); } define_one_cppc_ro(feedback_ctrs); static struct attribute *cppc_attrs[] = { &feedback_ctrs.attr, &reference_perf.attr, &wraparound_time.attr, &highest_perf.attr, &lowest_perf.attr, &lowest_nonlinear_perf.attr, &nominal_perf.attr, &nominal_freq.attr, &lowest_freq.attr, NULL }; static struct kobj_type cppc_ktype = { .sysfs_ops = &kobj_sysfs_ops, .default_attrs = cppc_attrs, }; static int check_pcc_chan(int pcc_ss_id, bool chk_err_bit) { int ret, status; struct cppc_pcc_data *pcc_ss_data = pcc_data[pcc_ss_id]; struct acpi_pcct_shared_memory __iomem *generic_comm_base = pcc_ss_data->pcc_comm_addr; if (!pcc_ss_data->platform_owns_pcc) return 0; /* * Poll PCC status register every 3us(delay_us) for maximum of * deadline_us(timeout_us) until PCC command complete bit is set(cond) */ ret = readw_relaxed_poll_timeout(&generic_comm_base->status, status, status & PCC_CMD_COMPLETE_MASK, 3, pcc_ss_data->deadline_us); if (likely(!ret)) { pcc_ss_data->platform_owns_pcc = false; if (chk_err_bit && (status & PCC_ERROR_MASK)) ret = -EIO; } if (unlikely(ret)) pr_err("PCC check channel failed for ss: %d. ret=%d\n", pcc_ss_id, ret); return ret; } /* * This function transfers the ownership of the PCC to the platform * So it must be called while holding write_lock(pcc_lock) */ static int send_pcc_cmd(int pcc_ss_id, u16 cmd) { int ret = -EIO, i; struct cppc_pcc_data *pcc_ss_data = pcc_data[pcc_ss_id]; struct acpi_pcct_shared_memory *generic_comm_base = (struct acpi_pcct_shared_memory *)pcc_ss_data->pcc_comm_addr; unsigned int time_delta; /* * For CMD_WRITE we know for a fact the caller should have checked * the channel before writing to PCC space */ if (cmd == CMD_READ) { /* * If there are pending cpc_writes, then we stole the channel * before write completion, so first send a WRITE command to * platform */ if (pcc_ss_data->pending_pcc_write_cmd) send_pcc_cmd(pcc_ss_id, CMD_WRITE); ret = check_pcc_chan(pcc_ss_id, false); if (ret) goto end; } else /* CMD_WRITE */ pcc_ss_data->pending_pcc_write_cmd = FALSE; /* * Handle the Minimum Request Turnaround Time(MRTT) * "The minimum amount of time that OSPM must wait after the completion * of a command before issuing the next command, in microseconds" */ if (pcc_ss_data->pcc_mrtt) { time_delta = ktime_us_delta(ktime_get(), pcc_ss_data->last_cmd_cmpl_time); if (pcc_ss_data->pcc_mrtt > time_delta) udelay(pcc_ss_data->pcc_mrtt - time_delta); } /* * Handle the non-zero Maximum Periodic Access Rate(MPAR) * "The maximum number of periodic requests that the subspace channel can * support, reported in commands per minute. 0 indicates no limitation." * * This parameter should be ideally zero or large enough so that it can * handle maximum number of requests that all the cores in the system can * collectively generate. If it is not, we will follow the spec and just * not send the request to the platform after hitting the MPAR limit in * any 60s window */ if (pcc_ss_data->pcc_mpar) { if (pcc_ss_data->mpar_count == 0) { time_delta = ktime_ms_delta(ktime_get(), pcc_ss_data->last_mpar_reset); if ((time_delta < 60 * MSEC_PER_SEC) && pcc_ss_data->last_mpar_reset) { pr_debug("PCC cmd for subspace %d not sent due to MPAR limit", pcc_ss_id); ret = -EIO; goto end; } pcc_ss_data->last_mpar_reset = ktime_get(); pcc_ss_data->mpar_count = pcc_ss_data->pcc_mpar; } pcc_ss_data->mpar_count--; } /* Write to the shared comm region. */ writew_relaxed(cmd, &generic_comm_base->command); /* Flip CMD COMPLETE bit */ writew_relaxed(0, &generic_comm_base->status); pcc_ss_data->platform_owns_pcc = true; /* Ring doorbell */ ret = mbox_send_message(pcc_ss_data->pcc_channel, &cmd); if (ret < 0) { pr_err("Err sending PCC mbox message. ss: %d cmd:%d, ret:%d\n", pcc_ss_id, cmd, ret); goto end; } /* wait for completion and check for PCC errro bit */ ret = check_pcc_chan(pcc_ss_id, true); if (pcc_ss_data->pcc_mrtt) pcc_ss_data->last_cmd_cmpl_time = ktime_get(); if (pcc_ss_data->pcc_channel->mbox->txdone_irq) mbox_chan_txdone(pcc_ss_data->pcc_channel, ret); else mbox_client_txdone(pcc_ss_data->pcc_channel, ret); end: if (cmd == CMD_WRITE) { if (unlikely(ret)) { for_each_possible_cpu(i) { struct cpc_desc *desc = per_cpu(cpc_desc_ptr, i); if (!desc) continue; if (desc->write_cmd_id == pcc_ss_data->pcc_write_cnt) desc->write_cmd_status = ret; } } pcc_ss_data->pcc_write_cnt++; wake_up_all(&pcc_ss_data->pcc_write_wait_q); } return ret; } static void cppc_chan_tx_done(struct mbox_client *cl, void *msg, int ret) { if (ret < 0) pr_debug("TX did not complete: CMD sent:%x, ret:%d\n", *(u16 *)msg, ret); else pr_debug("TX completed. CMD sent:%x, ret:%d\n", *(u16 *)msg, ret); } struct mbox_client cppc_mbox_cl = { .tx_done = cppc_chan_tx_done, .knows_txdone = true, }; static int acpi_get_psd(struct cpc_desc *cpc_ptr, acpi_handle handle) { int result = -EFAULT; acpi_status status = AE_OK; struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"}; struct acpi_buffer state = {0, NULL}; union acpi_object *psd = NULL; struct acpi_psd_package *pdomain; status = acpi_evaluate_object_typed(handle, "_PSD", NULL, &buffer, ACPI_TYPE_PACKAGE); if (ACPI_FAILURE(status)) return -ENODEV; psd = buffer.pointer; if (!psd || psd->package.count != 1) { pr_debug("Invalid _PSD data\n"); goto end; } pdomain = &(cpc_ptr->domain_info); state.length = sizeof(struct acpi_psd_package); state.pointer = pdomain; status = acpi_extract_package(&(psd->package.elements[0]), &format, &state); if (ACPI_FAILURE(status)) { pr_debug("Invalid _PSD data for CPU:%d\n", cpc_ptr->cpu_id); goto end; } if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) { pr_debug("Unknown _PSD:num_entries for CPU:%d\n", cpc_ptr->cpu_id); goto end; } if (pdomain->revision != ACPI_PSD_REV0_REVISION) { pr_debug("Unknown _PSD:revision for CPU: %d\n", cpc_ptr->cpu_id); goto end; } if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { pr_debug("Invalid _PSD:coord_type for CPU:%d\n", cpc_ptr->cpu_id); goto end; } result = 0; end: kfree(buffer.pointer); return result; } /** * acpi_get_psd_map - Map the CPUs in a common freq domain. * @all_cpu_data: Ptrs to CPU specific CPPC data including PSD info. * * Return: 0 for success or negative value for err. */ int acpi_get_psd_map(struct cppc_cpudata **all_cpu_data) { int count_target; int retval = 0; unsigned int i, j; cpumask_var_t covered_cpus; struct cppc_cpudata *pr, *match_pr; struct acpi_psd_package *pdomain; struct acpi_psd_package *match_pdomain; struct cpc_desc *cpc_ptr, *match_cpc_ptr; if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) return -ENOMEM; /* * Now that we have _PSD data from all CPUs, lets setup P-state * domain info. */ for_each_possible_cpu(i) { pr = all_cpu_data[i]; if (!pr) continue; if (cpumask_test_cpu(i, covered_cpus)) continue; cpc_ptr = per_cpu(cpc_desc_ptr, i); if (!cpc_ptr) { retval = -EFAULT; goto err_ret; } pdomain = &(cpc_ptr->domain_info); cpumask_set_cpu(i, pr->shared_cpu_map); cpumask_set_cpu(i, covered_cpus); if (pdomain->num_processors <= 1) continue; /* Validate the Domain info */ count_target = pdomain->num_processors; if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) pr->shared_type = CPUFREQ_SHARED_TYPE_ALL; else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) pr->shared_type = CPUFREQ_SHARED_TYPE_HW; else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) pr->shared_type = CPUFREQ_SHARED_TYPE_ANY; for_each_possible_cpu(j) { if (i == j) continue; match_cpc_ptr = per_cpu(cpc_desc_ptr, j); if (!match_cpc_ptr) { retval = -EFAULT; goto err_ret; } match_pdomain = &(match_cpc_ptr->domain_info); if (match_pdomain->domain != pdomain->domain) continue; /* Here i and j are in the same domain */ if (match_pdomain->num_processors != count_target) { retval = -EFAULT; goto err_ret; } if (pdomain->coord_type != match_pdomain->coord_type) { retval = -EFAULT; goto err_ret; } cpumask_set_cpu(j, covered_cpus); cpumask_set_cpu(j, pr->shared_cpu_map); } for_each_possible_cpu(j) { if (i == j) continue; match_pr = all_cpu_data[j]; if (!match_pr) continue; match_cpc_ptr = per_cpu(cpc_desc_ptr, j); if (!match_cpc_ptr) { retval = -EFAULT; goto err_ret; } match_pdomain = &(match_cpc_ptr->domain_info); if (match_pdomain->domain != pdomain->domain) continue; match_pr->shared_type = pr->shared_type; cpumask_copy(match_pr->shared_cpu_map, pr->shared_cpu_map); } } err_ret: for_each_possible_cpu(i) { pr = all_cpu_data[i]; if (!pr) continue; /* Assume no coordination on any error parsing domain info */ if (retval) { cpumask_clear(pr->shared_cpu_map); cpumask_set_cpu(i, pr->shared_cpu_map); pr->shared_type = CPUFREQ_SHARED_TYPE_ALL; } } free_cpumask_var(covered_cpus); return retval; } EXPORT_SYMBOL_GPL(acpi_get_psd_map); static int register_pcc_channel(int pcc_ss_idx) { struct acpi_pcct_hw_reduced *cppc_ss; u64 usecs_lat; if (pcc_ss_idx >= 0) { pcc_data[pcc_ss_idx]->pcc_channel = pcc_mbox_request_channel(&cppc_mbox_cl, pcc_ss_idx); if (IS_ERR(pcc_data[pcc_ss_idx]->pcc_channel)) { pr_err("Failed to find PCC channel for subspace %d\n", pcc_ss_idx); return -ENODEV; } /* * The PCC mailbox controller driver should * have parsed the PCCT (global table of all * PCC channels) and stored pointers to the * subspace communication region in con_priv. */ cppc_ss = (pcc_data[pcc_ss_idx]->pcc_channel)->con_priv; if (!cppc_ss) { pr_err("No PCC subspace found for %d CPPC\n", pcc_ss_idx); return -ENODEV; } /* * cppc_ss->latency is just a Nominal value. In reality * the remote processor could be much slower to reply. * So add an arbitrary amount of wait on top of Nominal. */ usecs_lat = NUM_RETRIES * cppc_ss->latency; pcc_data[pcc_ss_idx]->deadline_us = usecs_lat; pcc_data[pcc_ss_idx]->pcc_mrtt = cppc_ss->min_turnaround_time; pcc_data[pcc_ss_idx]->pcc_mpar = cppc_ss->max_access_rate; pcc_data[pcc_ss_idx]->pcc_nominal = cppc_ss->latency; pcc_data[pcc_ss_idx]->pcc_comm_addr = acpi_os_ioremap(cppc_ss->base_address, cppc_ss->length); if (!pcc_data[pcc_ss_idx]->pcc_comm_addr) { pr_err("Failed to ioremap PCC comm region mem for %d\n", pcc_ss_idx); return -ENOMEM; } /* Set flag so that we dont come here for each CPU. */ pcc_data[pcc_ss_idx]->pcc_channel_acquired = true; } return 0; } /** * cpc_ffh_supported() - check if FFH reading supported * * Check if the architecture has support for functional fixed hardware * read/write capability. * * Return: true for supported, false for not supported */ bool __weak cpc_ffh_supported(void) { return false; } /** * pcc_data_alloc() - Allocate the pcc_data memory for pcc subspace * * Check and allocate the cppc_pcc_data memory. * In some processor configurations it is possible that same subspace * is shared between multiple CPU's. This is seen especially in CPU's * with hardware multi-threading support. * * Return: 0 for success, errno for failure */ int pcc_data_alloc(int pcc_ss_id) { if (pcc_ss_id < 0 || pcc_ss_id >= MAX_PCC_SUBSPACES) return -EINVAL; if (pcc_data[pcc_ss_id]) { pcc_data[pcc_ss_id]->refcount++; } else { pcc_data[pcc_ss_id] = kzalloc(sizeof(struct cppc_pcc_data), GFP_KERNEL); if (!pcc_data[pcc_ss_id]) return -ENOMEM; pcc_data[pcc_ss_id]->refcount++; } return 0; } /* Check if CPPC revision + num_ent combination is supported */ static bool is_cppc_supported(int revision, int num_ent) { int expected_num_ent; switch (revision) { case CPPC_V2_REV: expected_num_ent = CPPC_V2_NUM_ENT; break; case CPPC_V3_REV: expected_num_ent = CPPC_V3_NUM_ENT; break; default: pr_debug("Firmware exports unsupported CPPC revision: %d\n", revision); return false; } if (expected_num_ent != num_ent) { pr_debug("Firmware exports %d entries. Expected: %d for CPPC rev:%d\n", num_ent, expected_num_ent, revision); return false; } return true; } /* * An example CPC table looks like the following. * * Name(_CPC, Package() * { * 17, * NumEntries * 1, * // Revision * ResourceTemplate(){Register(PCC, 32, 0, 0x120, 2)}, * // Highest Performance * ResourceTemplate(){Register(PCC, 32, 0, 0x124, 2)}, * // Nominal Performance * ResourceTemplate(){Register(PCC, 32, 0, 0x128, 2)}, * // Lowest Nonlinear Performance * ResourceTemplate(){Register(PCC, 32, 0, 0x12C, 2)}, * // Lowest Performance * ResourceTemplate(){Register(PCC, 32, 0, 0x130, 2)}, * // Guaranteed Performance Register * ResourceTemplate(){Register(PCC, 32, 0, 0x110, 2)}, * // Desired Performance Register * ResourceTemplate(){Register(SystemMemory, 0, 0, 0, 0)}, * .. * .. * .. * * } * Each Register() encodes how to access that specific register. * e.g. a sample PCC entry has the following encoding: * * Register ( * PCC, * AddressSpaceKeyword * 8, * //RegisterBitWidth * 8, * //RegisterBitOffset * 0x30, * //RegisterAddress * 9 * //AccessSize (subspace ID) * 0 * ) * } */ /** * acpi_cppc_processor_probe - Search for per CPU _CPC objects. * @pr: Ptr to acpi_processor containing this CPUs logical Id. * * Return: 0 for success or negative value for err. */ int acpi_cppc_processor_probe(struct acpi_processor *pr) { struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL}; union acpi_object *out_obj, *cpc_obj; struct cpc_desc *cpc_ptr; struct cpc_reg *gas_t; struct device *cpu_dev; acpi_handle handle = pr->handle; unsigned int num_ent, i, cpc_rev; int pcc_subspace_id = -1; acpi_status status; int ret = -EFAULT; /* Parse the ACPI _CPC table for this cpu. */ status = acpi_evaluate_object_typed(handle, "_CPC", NULL, &output, ACPI_TYPE_PACKAGE); if (ACPI_FAILURE(status)) { ret = -ENODEV; goto out_buf_free; } out_obj = (union acpi_object *) output.pointer; cpc_ptr = kzalloc(sizeof(struct cpc_desc), GFP_KERNEL); if (!cpc_ptr) { ret = -ENOMEM; goto out_buf_free; } /* First entry is NumEntries. */ cpc_obj = &out_obj->package.elements[0]; if (cpc_obj->type == ACPI_TYPE_INTEGER) { num_ent = cpc_obj->integer.value; } else { pr_debug("Unexpected entry type(%d) for NumEntries\n", cpc_obj->type); goto out_free; } cpc_ptr->num_entries = num_ent; /* Second entry should be revision. */ cpc_obj = &out_obj->package.elements[1]; if (cpc_obj->type == ACPI_TYPE_INTEGER) { cpc_rev = cpc_obj->integer.value; } else { pr_debug("Unexpected entry type(%d) for Revision\n", cpc_obj->type); goto out_free; } cpc_ptr->version = cpc_rev; if (!is_cppc_supported(cpc_rev, num_ent)) goto out_free; /* Iterate through remaining entries in _CPC */ for (i = 2; i < num_ent; i++) { cpc_obj = &out_obj->package.elements[i]; if (cpc_obj->type == ACPI_TYPE_INTEGER) { cpc_ptr->cpc_regs[i-2].type = ACPI_TYPE_INTEGER; cpc_ptr->cpc_regs[i-2].cpc_entry.int_value = cpc_obj->integer.value; } else if (cpc_obj->type == ACPI_TYPE_BUFFER) { gas_t = (struct cpc_reg *) cpc_obj->buffer.pointer; /* * The PCC Subspace index is encoded inside * the CPC table entries. The same PCC index * will be used for all the PCC entries, * so extract it only once. */ if (gas_t->space_id == ACPI_ADR_SPACE_PLATFORM_COMM) { if (pcc_subspace_id < 0) { pcc_subspace_id = gas_t->access_width; if (pcc_data_alloc(pcc_subspace_id)) goto out_free; } else if (pcc_subspace_id != gas_t->access_width) { pr_debug("Mismatched PCC ids.\n"); goto out_free; } } else if (gas_t->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) { if (gas_t->address) { void __iomem *addr; addr = ioremap(gas_t->address, gas_t->bit_width/8); if (!addr) goto out_free; cpc_ptr->cpc_regs[i-2].sys_mem_vaddr = addr; } } else { if (gas_t->space_id != ACPI_ADR_SPACE_FIXED_HARDWARE || !cpc_ffh_supported()) { /* Support only PCC ,SYS MEM and FFH type regs */ pr_debug("Unsupported register type: %d\n", gas_t->space_id); goto out_free; } } cpc_ptr->cpc_regs[i-2].type = ACPI_TYPE_BUFFER; memcpy(&cpc_ptr->cpc_regs[i-2].cpc_entry.reg, gas_t, sizeof(*gas_t)); } else { pr_debug("Err in entry:%d in CPC table of CPU:%d \n", i, pr->id); goto out_free; } } per_cpu(cpu_pcc_subspace_idx, pr->id) = pcc_subspace_id; /* * Initialize the remaining cpc_regs as unsupported. * Example: In case FW exposes CPPC v2, the below loop will initialize * LOWEST_FREQ and NOMINAL_FREQ regs as unsupported */ for (i = num_ent - 2; i < MAX_CPC_REG_ENT; i++) { cpc_ptr->cpc_regs[i].type = ACPI_TYPE_INTEGER; cpc_ptr->cpc_regs[i].cpc_entry.int_value = 0; } /* Store CPU Logical ID */ cpc_ptr->cpu_id = pr->id; /* Parse PSD data for this CPU */ ret = acpi_get_psd(cpc_ptr, handle); if (ret) goto out_free; /* Register PCC channel once for all PCC subspace id. */ if (pcc_subspace_id >= 0 && !pcc_data[pcc_subspace_id]->pcc_channel_acquired) { ret = register_pcc_channel(pcc_subspace_id); if (ret) goto out_free; init_rwsem(&pcc_data[pcc_subspace_id]->pcc_lock); init_waitqueue_head(&pcc_data[pcc_subspace_id]->pcc_write_wait_q); } /* Everything looks okay */ pr_debug("Parsed CPC struct for CPU: %d\n", pr->id); /* Add per logical CPU nodes for reading its feedback counters. */ cpu_dev = get_cpu_device(pr->id); if (!cpu_dev) { ret = -EINVAL; goto out_free; } /* Plug PSD data into this CPUs CPC descriptor. */ per_cpu(cpc_desc_ptr, pr->id) = cpc_ptr; ret = kobject_init_and_add(&cpc_ptr->kobj, &cppc_ktype, &cpu_dev->kobj, "acpi_cppc"); if (ret) { per_cpu(cpc_desc_ptr, pr->id) = NULL; goto out_free; } kfree(output.pointer); return 0; out_free: /* Free all the mapped sys mem areas for this CPU */ for (i = 2; i < cpc_ptr->num_entries; i++) { void __iomem *addr = cpc_ptr->cpc_regs[i-2].sys_mem_vaddr; if (addr) iounmap(addr); } kfree(cpc_ptr); out_buf_free: kfree(output.pointer); return ret; } EXPORT_SYMBOL_GPL(acpi_cppc_processor_probe); /** * acpi_cppc_processor_exit - Cleanup CPC structs. * @pr: Ptr to acpi_processor containing this CPUs logical Id. * * Return: Void */ void acpi_cppc_processor_exit(struct acpi_processor *pr) { struct cpc_desc *cpc_ptr; unsigned int i; void __iomem *addr; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, pr->id); if (pcc_ss_id >=0 && pcc_data[pcc_ss_id]) { if (pcc_data[pcc_ss_id]->pcc_channel_acquired) { pcc_data[pcc_ss_id]->refcount--; if (!pcc_data[pcc_ss_id]->refcount) { pcc_mbox_free_channel(pcc_data[pcc_ss_id]->pcc_channel); pcc_data[pcc_ss_id]->pcc_channel_acquired = 0; kfree(pcc_data[pcc_ss_id]); } } } cpc_ptr = per_cpu(cpc_desc_ptr, pr->id); if (!cpc_ptr) return; /* Free all the mapped sys mem areas for this CPU */ for (i = 2; i < cpc_ptr->num_entries; i++) { addr = cpc_ptr->cpc_regs[i-2].sys_mem_vaddr; if (addr) iounmap(addr); } kobject_put(&cpc_ptr->kobj); kfree(cpc_ptr); } EXPORT_SYMBOL_GPL(acpi_cppc_processor_exit); /** * cpc_read_ffh() - Read FFH register * @cpunum: cpu number to read * @reg: cppc register information * @val: place holder for return value * * Read bit_width bits from a specified address and bit_offset * * Return: 0 for success and error code */ int __weak cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val) { return -ENOTSUPP; } /** * cpc_write_ffh() - Write FFH register * @cpunum: cpu number to write * @reg: cppc register information * @val: value to write * * Write value of bit_width bits to a specified address and bit_offset * * Return: 0 for success and error code */ int __weak cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val) { return -ENOTSUPP; } /* * Since cpc_read and cpc_write are called while holding pcc_lock, it should be * as fast as possible. We have already mapped the PCC subspace during init, so * we can directly write to it. */ static int cpc_read(int cpu, struct cpc_register_resource *reg_res, u64 *val) { int ret_val = 0; void __iomem *vaddr = 0; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg = ®_res->cpc_entry.reg; if (reg_res->type == ACPI_TYPE_INTEGER) { *val = reg_res->cpc_entry.int_value; return ret_val; } *val = 0; if (reg->space_id == ACPI_ADR_SPACE_PLATFORM_COMM && pcc_ss_id >= 0) vaddr = GET_PCC_VADDR(reg->address, pcc_ss_id); else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) vaddr = reg_res->sys_mem_vaddr; else if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) return cpc_read_ffh(cpu, reg, val); else return acpi_os_read_memory((acpi_physical_address)reg->address, val, reg->bit_width); switch (reg->bit_width) { case 8: *val = readb_relaxed(vaddr); break; case 16: *val = readw_relaxed(vaddr); break; case 32: *val = readl_relaxed(vaddr); break; case 64: *val = readq_relaxed(vaddr); break; default: pr_debug("Error: Cannot read %u bit width from PCC for ss: %d\n", reg->bit_width, pcc_ss_id); ret_val = -EFAULT; } return ret_val; } static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) { int ret_val = 0; void __iomem *vaddr = 0; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cpc_reg *reg = ®_res->cpc_entry.reg; if (reg->space_id == ACPI_ADR_SPACE_PLATFORM_COMM && pcc_ss_id >= 0) vaddr = GET_PCC_VADDR(reg->address, pcc_ss_id); else if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) vaddr = reg_res->sys_mem_vaddr; else if (reg->space_id == ACPI_ADR_SPACE_FIXED_HARDWARE) return cpc_write_ffh(cpu, reg, val); else return acpi_os_write_memory((acpi_physical_address)reg->address, val, reg->bit_width); switch (reg->bit_width) { case 8: writeb_relaxed(val, vaddr); break; case 16: writew_relaxed(val, vaddr); break; case 32: writel_relaxed(val, vaddr); break; case 64: writeq_relaxed(val, vaddr); break; default: pr_debug("Error: Cannot write %u bit width to PCC for ss: %d\n", reg->bit_width, pcc_ss_id); ret_val = -EFAULT; break; } return ret_val; } /** * cppc_get_perf_caps - Get a CPUs performance capabilities. * @cpunum: CPU from which to get capabilities info. * @perf_caps: ptr to cppc_perf_caps. See cppc_acpi.h * * Return: 0 for success with perf_caps populated else -ERRNO. */ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps) { struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum); struct cpc_register_resource *highest_reg, *lowest_reg, *lowest_non_linear_reg, *nominal_reg, *guaranteed_reg, *low_freq_reg = NULL, *nom_freq_reg = NULL; u64 high, low, guaranteed, nom, min_nonlinear, low_f = 0, nom_f = 0; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); struct cppc_pcc_data *pcc_ss_data = NULL; int ret = 0, regs_in_pcc = 0; if (!cpc_desc) { pr_debug("No CPC descriptor for CPU:%d\n", cpunum); return -ENODEV; } highest_reg = &cpc_desc->cpc_regs[HIGHEST_PERF]; lowest_reg = &cpc_desc->cpc_regs[LOWEST_PERF]; lowest_non_linear_reg = &cpc_desc->cpc_regs[LOW_NON_LINEAR_PERF]; nominal_reg = &cpc_desc->cpc_regs[NOMINAL_PERF]; low_freq_reg = &cpc_desc->cpc_regs[LOWEST_FREQ]; nom_freq_reg = &cpc_desc->cpc_regs[NOMINAL_FREQ]; guaranteed_reg = &cpc_desc->cpc_regs[GUARANTEED_PERF]; /* Are any of the regs PCC ?*/ if (CPC_IN_PCC(highest_reg) || CPC_IN_PCC(lowest_reg) || CPC_IN_PCC(lowest_non_linear_reg) || CPC_IN_PCC(nominal_reg) || CPC_IN_PCC(low_freq_reg) || CPC_IN_PCC(nom_freq_reg)) { if (pcc_ss_id < 0) { pr_debug("Invalid pcc_ss_id\n"); return -ENODEV; } pcc_ss_data = pcc_data[pcc_ss_id]; regs_in_pcc = 1; down_write(&pcc_ss_data->pcc_lock); /* Ring doorbell once to update PCC subspace */ if (send_pcc_cmd(pcc_ss_id, CMD_READ) < 0) { ret = -EIO; goto out_err; } } cpc_read(cpunum, highest_reg, &high); perf_caps->highest_perf = high; cpc_read(cpunum, lowest_reg, &low); perf_caps->lowest_perf = low; cpc_read(cpunum, nominal_reg, &nom); perf_caps->nominal_perf = nom; cpc_read(cpunum, guaranteed_reg, &guaranteed); perf_caps->guaranteed_perf = guaranteed; cpc_read(cpunum, lowest_non_linear_reg, &min_nonlinear); perf_caps->lowest_nonlinear_perf = min_nonlinear; if (!high || !low || !nom || !min_nonlinear) ret = -EFAULT; /* Read optional lowest and nominal frequencies if present */ if (CPC_SUPPORTED(low_freq_reg)) cpc_read(cpunum, low_freq_reg, &low_f); if (CPC_SUPPORTED(nom_freq_reg)) cpc_read(cpunum, nom_freq_reg, &nom_f); perf_caps->lowest_freq = low_f; perf_caps->nominal_freq = nom_f; out_err: if (regs_in_pcc) up_write(&pcc_ss_data->pcc_lock); return ret; } EXPORT_SYMBOL_GPL(cppc_get_perf_caps); /** * cppc_get_perf_ctrs - Read a CPUs performance feedback counters. * @cpunum: CPU from which to read counters. * @perf_fb_ctrs: ptr to cppc_perf_fb_ctrs. See cppc_acpi.h * * Return: 0 for success with perf_fb_ctrs populated else -ERRNO. */ int cppc_get_perf_ctrs(int cpunum, struct cppc_perf_fb_ctrs *perf_fb_ctrs) { struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpunum); struct cpc_register_resource *delivered_reg, *reference_reg, *ref_perf_reg, *ctr_wrap_reg; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpunum); struct cppc_pcc_data *pcc_ss_data = NULL; u64 delivered, reference, ref_perf, ctr_wrap_time; int ret = 0, regs_in_pcc = 0; if (!cpc_desc) { pr_debug("No CPC descriptor for CPU:%d\n", cpunum); return -ENODEV; } delivered_reg = &cpc_desc->cpc_regs[DELIVERED_CTR]; reference_reg = &cpc_desc->cpc_regs[REFERENCE_CTR]; ref_perf_reg = &cpc_desc->cpc_regs[REFERENCE_PERF]; ctr_wrap_reg = &cpc_desc->cpc_regs[CTR_WRAP_TIME]; /* * If refernce perf register is not supported then we should * use the nominal perf value */ if (!CPC_SUPPORTED(ref_perf_reg)) ref_perf_reg = &cpc_desc->cpc_regs[NOMINAL_PERF]; /* Are any of the regs PCC ?*/ if (CPC_IN_PCC(delivered_reg) || CPC_IN_PCC(reference_reg) || CPC_IN_PCC(ctr_wrap_reg) || CPC_IN_PCC(ref_perf_reg)) { if (pcc_ss_id < 0) { pr_debug("Invalid pcc_ss_id\n"); return -ENODEV; } pcc_ss_data = pcc_data[pcc_ss_id]; down_write(&pcc_ss_data->pcc_lock); regs_in_pcc = 1; /* Ring doorbell once to update PCC subspace */ if (send_pcc_cmd(pcc_ss_id, CMD_READ) < 0) { ret = -EIO; goto out_err; } } cpc_read(cpunum, delivered_reg, &delivered); cpc_read(cpunum, reference_reg, &reference); cpc_read(cpunum, ref_perf_reg, &ref_perf); /* * Per spec, if ctr_wrap_time optional register is unsupported, then the * performance counters are assumed to never wrap during the lifetime of * platform */ ctr_wrap_time = (u64)(~((u64)0)); if (CPC_SUPPORTED(ctr_wrap_reg)) cpc_read(cpunum, ctr_wrap_reg, &ctr_wrap_time); if (!delivered || !reference || !ref_perf) { ret = -EFAULT; goto out_err; } perf_fb_ctrs->delivered = delivered; perf_fb_ctrs->reference = reference; perf_fb_ctrs->reference_perf = ref_perf; perf_fb_ctrs->wraparound_time = ctr_wrap_time; out_err: if (regs_in_pcc) up_write(&pcc_ss_data->pcc_lock); return ret; } EXPORT_SYMBOL_GPL(cppc_get_perf_ctrs); /** * cppc_set_perf - Set a CPUs performance controls. * @cpu: CPU for which to set performance controls. * @perf_ctrls: ptr to cppc_perf_ctrls. See cppc_acpi.h * * Return: 0 for success, -ERRNO otherwise. */ int cppc_set_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls) { struct cpc_desc *cpc_desc = per_cpu(cpc_desc_ptr, cpu); struct cpc_register_resource *desired_reg; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu); struct cppc_pcc_data *pcc_ss_data = NULL; int ret = 0; if (!cpc_desc) { pr_debug("No CPC descriptor for CPU:%d\n", cpu); return -ENODEV; } desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF]; /* * This is Phase-I where we want to write to CPC registers * -> We want all CPUs to be able to execute this phase in parallel * * Since read_lock can be acquired by multiple CPUs simultaneously we * achieve that goal here */ if (CPC_IN_PCC(desired_reg)) { if (pcc_ss_id < 0) { pr_debug("Invalid pcc_ss_id\n"); return -ENODEV; } pcc_ss_data = pcc_data[pcc_ss_id]; down_read(&pcc_ss_data->pcc_lock); /* BEGIN Phase-I */ if (pcc_ss_data->platform_owns_pcc) { ret = check_pcc_chan(pcc_ss_id, false); if (ret) { up_read(&pcc_ss_data->pcc_lock); return ret; } } /* * Update the pending_write to make sure a PCC CMD_READ will not * arrive and steal the channel during the switch to write lock */ pcc_ss_data->pending_pcc_write_cmd = true; cpc_desc->write_cmd_id = pcc_ss_data->pcc_write_cnt; cpc_desc->write_cmd_status = 0; } /* * Skip writing MIN/MAX until Linux knows how to come up with * useful values. */ cpc_write(cpu, desired_reg, perf_ctrls->desired_perf); if (CPC_IN_PCC(desired_reg)) up_read(&pcc_ss_data->pcc_lock); /* END Phase-I */ /* * This is Phase-II where we transfer the ownership of PCC to Platform * * Short Summary: Basically if we think of a group of cppc_set_perf * requests that happened in short overlapping interval. The last CPU to * come out of Phase-I will enter Phase-II and ring the doorbell. * * We have the following requirements for Phase-II: * 1. We want to execute Phase-II only when there are no CPUs * currently executing in Phase-I * 2. Once we start Phase-II we want to avoid all other CPUs from * entering Phase-I. * 3. We want only one CPU among all those who went through Phase-I * to run phase-II * * If write_trylock fails to get the lock and doesn't transfer the * PCC ownership to the platform, then one of the following will be TRUE * 1. There is at-least one CPU in Phase-I which will later execute * write_trylock, so the CPUs in Phase-I will be responsible for * executing the Phase-II. * 2. Some other CPU has beaten this CPU to successfully execute the * write_trylock and has already acquired the write_lock. We know for a * fact it(other CPU acquiring the write_lock) couldn't have happened * before this CPU's Phase-I as we held the read_lock. * 3. Some other CPU executing pcc CMD_READ has stolen the * down_write, in which case, send_pcc_cmd will check for pending * CMD_WRITE commands by checking the pending_pcc_write_cmd. * So this CPU can be certain that its request will be delivered * So in all cases, this CPU knows that its request will be delivered * by another CPU and can return * * After getting the down_write we still need to check for * pending_pcc_write_cmd to take care of the following scenario * The thread running this code could be scheduled out between * Phase-I and Phase-II. Before it is scheduled back on, another CPU * could have delivered the request to Platform by triggering the * doorbell and transferred the ownership of PCC to platform. So this * avoids triggering an unnecessary doorbell and more importantly before * triggering the doorbell it makes sure that the PCC channel ownership * is still with OSPM. * pending_pcc_write_cmd can also be cleared by a different CPU, if * there was a pcc CMD_READ waiting on down_write and it steals the lock * before the pcc CMD_WRITE is completed. pcc_send_cmd checks for this * case during a CMD_READ and if there are pending writes it delivers * the write command before servicing the read command */ if (CPC_IN_PCC(desired_reg)) { if (down_write_trylock(&pcc_ss_data->pcc_lock)) {/* BEGIN Phase-II */ /* Update only if there are pending write commands */ if (pcc_ss_data->pending_pcc_write_cmd) send_pcc_cmd(pcc_ss_id, CMD_WRITE); up_write(&pcc_ss_data->pcc_lock); /* END Phase-II */ } else /* Wait until pcc_write_cnt is updated by send_pcc_cmd */ wait_event(pcc_ss_data->pcc_write_wait_q, cpc_desc->write_cmd_id != pcc_ss_data->pcc_write_cnt); /* send_pcc_cmd updates the status in case of failure */ ret = cpc_desc->write_cmd_status; } return ret; } EXPORT_SYMBOL_GPL(cppc_set_perf); /** * cppc_get_transition_latency - returns frequency transition latency in ns * * ACPI CPPC does not explicitly specifiy how a platform can specify the * transition latency for perfromance change requests. The closest we have * is the timing information from the PCCT tables which provides the info * on the number and frequency of PCC commands the platform can handle. */ unsigned int cppc_get_transition_latency(int cpu_num) { /* * Expected transition latency is based on the PCCT timing values * Below are definition from ACPI spec: * pcc_nominal- Expected latency to process a command, in microseconds * pcc_mpar - The maximum number of periodic requests that the subspace * channel can support, reported in commands per minute. 0 * indicates no limitation. * pcc_mrtt - The minimum amount of time that OSPM must wait after the * completion of a command before issuing the next command, * in microseconds. */ unsigned int latency_ns = 0; struct cpc_desc *cpc_desc; struct cpc_register_resource *desired_reg; int pcc_ss_id = per_cpu(cpu_pcc_subspace_idx, cpu_num); struct cppc_pcc_data *pcc_ss_data; cpc_desc = per_cpu(cpc_desc_ptr, cpu_num); if (!cpc_desc) return CPUFREQ_ETERNAL; desired_reg = &cpc_desc->cpc_regs[DESIRED_PERF]; if (!CPC_IN_PCC(desired_reg)) return CPUFREQ_ETERNAL; if (pcc_ss_id < 0) return CPUFREQ_ETERNAL; pcc_ss_data = pcc_data[pcc_ss_id]; if (pcc_ss_data->pcc_mpar) latency_ns = 60 * (1000 * 1000 * 1000 / pcc_ss_data->pcc_mpar); latency_ns = max(latency_ns, pcc_ss_data->pcc_nominal * 1000); latency_ns = max(latency_ns, pcc_ss_data->pcc_mrtt * 1000); return latency_ns; } EXPORT_SYMBOL_GPL(cppc_get_transition_latency);
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