diff options
Diffstat (limited to 'drivers/perf/arm_cspmu/arm_cspmu.c')
| -rw-r--r-- | drivers/perf/arm_cspmu/arm_cspmu.c | 1428 |
1 files changed, 1428 insertions, 0 deletions
diff --git a/drivers/perf/arm_cspmu/arm_cspmu.c b/drivers/perf/arm_cspmu/arm_cspmu.c new file mode 100644 index 000000000000..34430b68f602 --- /dev/null +++ b/drivers/perf/arm_cspmu/arm_cspmu.c @@ -0,0 +1,1428 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ARM CoreSight Architecture PMU driver. + * + * This driver adds support for uncore PMU based on ARM CoreSight Performance + * Monitoring Unit Architecture. The PMU is accessible via MMIO registers and + * like other uncore PMUs, it does not support process specific events and + * cannot be used in sampling mode. + * + * This code is based on other uncore PMUs like ARM DSU PMU. It provides a + * generic implementation to operate the PMU according to CoreSight PMU + * architecture and ACPI ARM PMU table (APMT) documents below: + * - ARM CoreSight PMU architecture document number: ARM IHI 0091 A.a-00bet0. + * - APMT document number: ARM DEN0117. + * + * The user should refer to the vendor technical documentation to get details + * about the supported events. + * + * Copyright (c) 2022-2023, NVIDIA CORPORATION & AFFILIATES. All rights reserved. + * + */ + +#include <linux/acpi.h> +#include <linux/cacheinfo.h> +#include <linux/ctype.h> +#include <linux/interrupt.h> +#include <linux/io-64-nonatomic-lo-hi.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/perf_event.h> +#include <linux/platform_device.h> + +#include "arm_cspmu.h" + +#define PMUNAME "arm_cspmu" +#define DRVNAME "arm-cs-arch-pmu" + +#define ARM_CSPMU_CPUMASK_ATTR(_name, _config) \ + ARM_CSPMU_EXT_ATTR(_name, arm_cspmu_cpumask_show, \ + (unsigned long)_config) + +/* Each SET/CLR register supports up to 32 counters. */ +#define ARM_CSPMU_SET_CLR_COUNTER_SHIFT 5 +#define ARM_CSPMU_SET_CLR_COUNTER_NUM \ + (1 << ARM_CSPMU_SET_CLR_COUNTER_SHIFT) + +/* Convert counter idx into SET/CLR register number. */ +#define COUNTER_TO_SET_CLR_ID(idx) \ + (idx >> ARM_CSPMU_SET_CLR_COUNTER_SHIFT) + +/* Convert counter idx into SET/CLR register bit. */ +#define COUNTER_TO_SET_CLR_BIT(idx) \ + (idx & (ARM_CSPMU_SET_CLR_COUNTER_NUM - 1)) + +#define ARM_CSPMU_ACTIVE_CPU_MASK 0x0 +#define ARM_CSPMU_ASSOCIATED_CPU_MASK 0x1 + +/* + * Maximum poll count for reading counter value using high-low-high sequence. + */ +#define HILOHI_MAX_POLL 1000 + +static unsigned long arm_cspmu_cpuhp_state; + +static DEFINE_MUTEX(arm_cspmu_lock); + +static void arm_cspmu_set_ev_filter(struct arm_cspmu *cspmu, + const struct perf_event *event); +static void arm_cspmu_set_cc_filter(struct arm_cspmu *cspmu, + const struct perf_event *event); + +static struct acpi_apmt_node *arm_cspmu_apmt_node(struct device *dev) +{ + struct acpi_apmt_node **ptr = dev_get_platdata(dev); + + return ptr ? *ptr : NULL; +} + +/* + * In CoreSight PMU architecture, all of the MMIO registers are 32-bit except + * counter register. The counter register can be implemented as 32-bit or 64-bit + * register depending on the value of PMCFGR.SIZE field. For 64-bit access, + * single-copy 64-bit atomic support is implementation defined. APMT node flag + * is used to identify if the PMU supports 64-bit single copy atomic. If 64-bit + * single copy atomic is not supported, the driver treats the register as a pair + * of 32-bit register. + */ + +/* + * Read 64-bit register as a pair of 32-bit registers using hi-lo-hi sequence. + */ +static u64 read_reg64_hilohi(const void __iomem *addr, u32 max_poll_count) +{ + u32 val_lo, val_hi; + u64 val; + + /* Use high-low-high sequence to avoid tearing */ + do { + if (max_poll_count-- == 0) { + pr_err("ARM CSPMU: timeout hi-low-high sequence\n"); + return 0; + } + + val_hi = readl(addr + 4); + val_lo = readl(addr); + } while (val_hi != readl(addr + 4)); + + val = (((u64)val_hi << 32) | val_lo); + + return val; +} + +/* Check if cycle counter is supported. */ +static inline bool supports_cycle_counter(const struct arm_cspmu *cspmu) +{ + return (cspmu->pmcfgr & PMCFGR_CC); +} + +/* Get counter size, which is (PMCFGR_SIZE + 1). */ +static inline u32 counter_size(const struct arm_cspmu *cspmu) +{ + return FIELD_GET(PMCFGR_SIZE, cspmu->pmcfgr) + 1; +} + +/* Get counter mask. */ +static inline u64 counter_mask(const struct arm_cspmu *cspmu) +{ + return GENMASK_ULL(counter_size(cspmu) - 1, 0); +} + +/* Check if counter is implemented as 64-bit register. */ +static inline bool use_64b_counter_reg(const struct arm_cspmu *cspmu) +{ + return (counter_size(cspmu) > 32); +} + +ssize_t arm_cspmu_sysfs_event_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct perf_pmu_events_attr *pmu_attr; + + pmu_attr = container_of(attr, typeof(*pmu_attr), attr); + return sysfs_emit(buf, "event=0x%llx\n", pmu_attr->id); +} +EXPORT_SYMBOL_GPL(arm_cspmu_sysfs_event_show); + +/* Default event list. */ +static struct attribute *arm_cspmu_event_attrs[] = { + ARM_CSPMU_EVENT_ATTR(cycles, ARM_CSPMU_EVT_CYCLES_DEFAULT), + NULL, +}; + +static struct attribute ** +arm_cspmu_get_event_attrs(const struct arm_cspmu *cspmu) +{ + struct attribute **attrs; + + attrs = devm_kmemdup(cspmu->dev, arm_cspmu_event_attrs, + sizeof(arm_cspmu_event_attrs), GFP_KERNEL); + + return attrs; +} + +static umode_t +arm_cspmu_event_attr_is_visible(struct kobject *kobj, + struct attribute *attr, int unused) +{ + struct device *dev = kobj_to_dev(kobj); + struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev)); + struct perf_pmu_events_attr *eattr; + + eattr = container_of(attr, typeof(*eattr), attr.attr); + + /* Hide cycle event if not supported */ + if (!supports_cycle_counter(cspmu) && + eattr->id == ARM_CSPMU_EVT_CYCLES_DEFAULT) + return 0; + + return attr->mode; +} + +static struct attribute *arm_cspmu_format_attrs[] = { + ARM_CSPMU_FORMAT_EVENT_ATTR, + ARM_CSPMU_FORMAT_FILTER_ATTR, + ARM_CSPMU_FORMAT_FILTER2_ATTR, + NULL, +}; + +static struct attribute ** +arm_cspmu_get_format_attrs(const struct arm_cspmu *cspmu) +{ + struct attribute **attrs; + + attrs = devm_kmemdup(cspmu->dev, arm_cspmu_format_attrs, + sizeof(arm_cspmu_format_attrs), GFP_KERNEL); + + return attrs; +} + +static u32 arm_cspmu_event_type(const struct perf_event *event) +{ + return event->attr.config & ARM_CSPMU_EVENT_MASK; +} + +static bool arm_cspmu_is_cycle_counter_event(const struct perf_event *event) +{ + return (event->attr.config == ARM_CSPMU_EVT_CYCLES_DEFAULT); +} + +static ssize_t arm_cspmu_identifier_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(dev_get_drvdata(dev)); + + return sysfs_emit(page, "%s\n", cspmu->identifier); +} + +static struct device_attribute arm_cspmu_identifier_attr = + __ATTR(identifier, 0444, arm_cspmu_identifier_show, NULL); + +static struct attribute *arm_cspmu_identifier_attrs[] = { + &arm_cspmu_identifier_attr.attr, + NULL, +}; + +static struct attribute_group arm_cspmu_identifier_attr_group = { + .attrs = arm_cspmu_identifier_attrs, +}; + +static const char *arm_cspmu_get_identifier(const struct arm_cspmu *cspmu) +{ + const char *identifier = + devm_kasprintf(cspmu->dev, GFP_KERNEL, "%x", + cspmu->impl.pmiidr); + return identifier; +} + +static const char *arm_cspmu_type_str[ACPI_APMT_NODE_TYPE_COUNT] = { + "mc", + "smmu", + "pcie", + "acpi", + "cache", +}; + +static const char *arm_cspmu_get_name(const struct arm_cspmu *cspmu) +{ + struct device *dev; + struct acpi_apmt_node *apmt_node; + u8 pmu_type; + char *name; + char acpi_hid_string[ACPI_ID_LEN] = { 0 }; + static atomic_t pmu_idx[ACPI_APMT_NODE_TYPE_COUNT] = { 0 }; + + dev = cspmu->dev; + apmt_node = arm_cspmu_apmt_node(dev); + if (!apmt_node) + return devm_kasprintf(dev, GFP_KERNEL, PMUNAME "_%u", + atomic_fetch_inc(&pmu_idx[0])); + + pmu_type = apmt_node->type; + + if (pmu_type >= ACPI_APMT_NODE_TYPE_COUNT) { + dev_err(dev, "unsupported PMU type-%u\n", pmu_type); + return NULL; + } + + if (pmu_type == ACPI_APMT_NODE_TYPE_ACPI) { + memcpy(acpi_hid_string, + &apmt_node->inst_primary, + sizeof(apmt_node->inst_primary)); + name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%s_%u", PMUNAME, + arm_cspmu_type_str[pmu_type], + acpi_hid_string, + apmt_node->inst_secondary); + } else { + name = devm_kasprintf(dev, GFP_KERNEL, "%s_%s_%d", PMUNAME, + arm_cspmu_type_str[pmu_type], + atomic_fetch_inc(&pmu_idx[pmu_type])); + } + + return name; +} + +static ssize_t arm_cspmu_cpumask_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct pmu *pmu = dev_get_drvdata(dev); + struct arm_cspmu *cspmu = to_arm_cspmu(pmu); + struct dev_ext_attribute *eattr = + container_of(attr, struct dev_ext_attribute, attr); + unsigned long mask_id = (unsigned long)eattr->var; + const cpumask_t *cpumask; + + switch (mask_id) { + case ARM_CSPMU_ACTIVE_CPU_MASK: + cpumask = &cspmu->active_cpu; + break; + case ARM_CSPMU_ASSOCIATED_CPU_MASK: + cpumask = &cspmu->associated_cpus; + break; + default: + return 0; + } + return cpumap_print_to_pagebuf(true, buf, cpumask); +} + +static struct attribute *arm_cspmu_cpumask_attrs[] = { + ARM_CSPMU_CPUMASK_ATTR(cpumask, ARM_CSPMU_ACTIVE_CPU_MASK), + ARM_CSPMU_CPUMASK_ATTR(associated_cpus, ARM_CSPMU_ASSOCIATED_CPU_MASK), + NULL, +}; + +static struct attribute_group arm_cspmu_cpumask_attr_group = { + .attrs = arm_cspmu_cpumask_attrs, +}; + +static struct arm_cspmu_impl_match impl_match[] = { + { + .module_name = "nvidia_cspmu", + .pmiidr_val = ARM_CSPMU_IMPL_ID_NVIDIA, + .pmiidr_mask = PMIIDR_IMPLEMENTER, + .module = NULL, + .impl_init_ops = NULL, + }, + { + .module_name = "ampere_cspmu", + .pmiidr_val = ARM_CSPMU_IMPL_ID_AMPERE, + .pmiidr_mask = PMIIDR_IMPLEMENTER, + .module = NULL, + .impl_init_ops = NULL, + }, + + {0} +}; + +static struct arm_cspmu_impl_match *arm_cspmu_impl_match_get(u32 pmiidr) +{ + struct arm_cspmu_impl_match *match = impl_match; + + for (; match->pmiidr_val; match++) { + u32 mask = match->pmiidr_mask; + + if ((match->pmiidr_val & mask) == (pmiidr & mask)) + return match; + } + + return NULL; +} + +static u32 arm_cspmu_get_pmiidr(struct arm_cspmu *cspmu) +{ + u32 pmiidr, pmpidr; + + pmiidr = readl(cspmu->base0 + PMIIDR); + + if (pmiidr != 0) + return pmiidr; + + /* Construct PMIIDR value from PMPIDRs. */ + + pmpidr = readl(cspmu->base0 + PMPIDR0); + pmiidr |= FIELD_PREP(PMIIDR_PRODUCTID_PART_0, + FIELD_GET(PMPIDR0_PART_0, pmpidr)); + + pmpidr = readl(cspmu->base0 + PMPIDR1); + pmiidr |= FIELD_PREP(PMIIDR_PRODUCTID_PART_1, + FIELD_GET(PMPIDR1_PART_1, pmpidr)); + pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_0, + FIELD_GET(PMPIDR1_DES_0, pmpidr)); + + pmpidr = readl(cspmu->base0 + PMPIDR2); + pmiidr |= FIELD_PREP(PMIIDR_VARIANT, + FIELD_GET(PMPIDR2_REVISION, pmpidr)); + pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_1, + FIELD_GET(PMPIDR2_DES_1, pmpidr)); + + pmpidr = readl(cspmu->base0 + PMPIDR3); + pmiidr |= FIELD_PREP(PMIIDR_REVISION, + FIELD_GET(PMPIDR3_REVAND, pmpidr)); + + pmpidr = readl(cspmu->base0 + PMPIDR4); + pmiidr |= FIELD_PREP(PMIIDR_IMPLEMENTER_DES_2, + FIELD_GET(PMPIDR4_DES_2, pmpidr)); + + return pmiidr; +} + +#define DEFAULT_IMPL_OP(name) .name = arm_cspmu_##name + +static int arm_cspmu_init_impl_ops(struct arm_cspmu *cspmu) +{ + int ret = 0; + struct acpi_apmt_node *apmt_node = arm_cspmu_apmt_node(cspmu->dev); + struct arm_cspmu_impl_match *match; + + /* Start with a default PMU implementation */ + cspmu->impl.module = THIS_MODULE; + cspmu->impl.pmiidr = arm_cspmu_get_pmiidr(cspmu); + cspmu->impl.ops = (struct arm_cspmu_impl_ops) { + DEFAULT_IMPL_OP(get_event_attrs), + DEFAULT_IMPL_OP(get_format_attrs), + DEFAULT_IMPL_OP(get_identifier), + DEFAULT_IMPL_OP(get_name), + DEFAULT_IMPL_OP(is_cycle_counter_event), + DEFAULT_IMPL_OP(event_type), + DEFAULT_IMPL_OP(set_cc_filter), + DEFAULT_IMPL_OP(set_ev_filter), + DEFAULT_IMPL_OP(event_attr_is_visible), + }; + + /* Firmware may override implementer/product ID from PMIIDR */ + if (apmt_node && apmt_node->impl_id) + cspmu->impl.pmiidr = apmt_node->impl_id; + + /* Find implementer specific attribute ops. */ + match = arm_cspmu_impl_match_get(cspmu->impl.pmiidr); + + /* Load implementer module and initialize the callbacks. */ + if (match) { + mutex_lock(&arm_cspmu_lock); + + if (match->impl_init_ops) { + /* Prevent unload until PMU registration is done. */ + if (try_module_get(match->module)) { + cspmu->impl.module = match->module; + cspmu->impl.match = match; + ret = match->impl_init_ops(cspmu); + if (ret) + module_put(match->module); + } else { + WARN(1, "arm_cspmu failed to get module: %s\n", + match->module_name); + ret = -EINVAL; + } + } else { + request_module_nowait(match->module_name); + ret = -EPROBE_DEFER; + } + + mutex_unlock(&arm_cspmu_lock); + } + + return ret; +} + +static struct attribute_group * +arm_cspmu_alloc_event_attr_group(struct arm_cspmu *cspmu) +{ + struct attribute_group *event_group; + struct device *dev = cspmu->dev; + const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops; + + event_group = + devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL); + if (!event_group) + return NULL; + + event_group->name = "events"; + event_group->is_visible = impl_ops->event_attr_is_visible; + event_group->attrs = impl_ops->get_event_attrs(cspmu); + + if (!event_group->attrs) + return NULL; + + return event_group; +} + +static struct attribute_group * +arm_cspmu_alloc_format_attr_group(struct arm_cspmu *cspmu) +{ + struct attribute_group *format_group; + struct device *dev = cspmu->dev; + + format_group = + devm_kzalloc(dev, sizeof(struct attribute_group), GFP_KERNEL); + if (!format_group) + return NULL; + + format_group->name = "format"; + format_group->attrs = cspmu->impl.ops.get_format_attrs(cspmu); + + if (!format_group->attrs) + return NULL; + + return format_group; +} + +static int arm_cspmu_alloc_attr_groups(struct arm_cspmu *cspmu) +{ + const struct attribute_group **attr_groups = cspmu->attr_groups; + const struct arm_cspmu_impl_ops *impl_ops = &cspmu->impl.ops; + + cspmu->identifier = impl_ops->get_identifier(cspmu); + cspmu->name = impl_ops->get_name(cspmu); + + if (!cspmu->identifier || !cspmu->name) + return -ENOMEM; + + attr_groups[0] = arm_cspmu_alloc_event_attr_group(cspmu); + attr_groups[1] = arm_cspmu_alloc_format_attr_group(cspmu); + attr_groups[2] = &arm_cspmu_identifier_attr_group; + attr_groups[3] = &arm_cspmu_cpumask_attr_group; + + if (!attr_groups[0] || !attr_groups[1]) + return -ENOMEM; + + return 0; +} + +static inline void arm_cspmu_reset_counters(struct arm_cspmu *cspmu) +{ + writel(PMCR_C | PMCR_P, cspmu->base0 + PMCR); +} + +static inline void arm_cspmu_start_counters(struct arm_cspmu *cspmu) +{ + writel(PMCR_E, cspmu->base0 + PMCR); +} + +static inline void arm_cspmu_stop_counters(struct arm_cspmu *cspmu) +{ + writel(0, cspmu->base0 + PMCR); +} + +static void arm_cspmu_enable(struct pmu *pmu) +{ + bool disabled; + struct arm_cspmu *cspmu = to_arm_cspmu(pmu); + + disabled = bitmap_empty(cspmu->hw_events.used_ctrs, + cspmu->num_logical_ctrs); + + if (disabled) + return; + + arm_cspmu_start_counters(cspmu); +} + +static void arm_cspmu_disable(struct pmu *pmu) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(pmu); + + arm_cspmu_stop_counters(cspmu); +} + +static int arm_cspmu_get_event_idx(struct arm_cspmu_hw_events *hw_events, + struct perf_event *event) +{ + int idx, ret; + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + + if (supports_cycle_counter(cspmu)) { + if (cspmu->impl.ops.is_cycle_counter_event(event)) { + /* Search for available cycle counter. */ + if (test_and_set_bit(cspmu->cycle_counter_logical_idx, + hw_events->used_ctrs)) + return -EAGAIN; + + return cspmu->cycle_counter_logical_idx; + } + + /* + * Search a regular counter from the used counter bitmap. + * The cycle counter divides the bitmap into two parts. Search + * the first then second half to exclude the cycle counter bit. + */ + idx = find_first_zero_bit(hw_events->used_ctrs, + cspmu->cycle_counter_logical_idx); + if (idx >= cspmu->cycle_counter_logical_idx) { + idx = find_next_zero_bit( + hw_events->used_ctrs, + cspmu->num_logical_ctrs, + cspmu->cycle_counter_logical_idx + 1); + } + } else { + idx = find_first_zero_bit(hw_events->used_ctrs, + cspmu->num_logical_ctrs); + } + + if (idx >= cspmu->num_logical_ctrs) + return -EAGAIN; + + if (cspmu->impl.ops.validate_event) { + ret = cspmu->impl.ops.validate_event(cspmu, event); + if (ret) + return ret; + } + + set_bit(idx, hw_events->used_ctrs); + + return idx; +} + +static bool arm_cspmu_validate_event(struct pmu *pmu, + struct arm_cspmu_hw_events *hw_events, + struct perf_event *event) +{ + if (is_software_event(event)) + return true; + + /* Reject groups spanning multiple HW PMUs. */ + if (event->pmu != pmu) + return false; + + return (arm_cspmu_get_event_idx(hw_events, event) >= 0); +} + +/* + * Make sure the group of events can be scheduled at once + * on the PMU. + */ +static bool arm_cspmu_validate_group(struct perf_event *event) +{ + struct perf_event *sibling, *leader = event->group_leader; + struct arm_cspmu_hw_events fake_hw_events; + + if (event->group_leader == event) + return true; + + memset(&fake_hw_events, 0, sizeof(fake_hw_events)); + + if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events, leader)) + return false; + + for_each_sibling_event(sibling, leader) { + if (!arm_cspmu_validate_event(event->pmu, &fake_hw_events, + sibling)) + return false; + } + + return arm_cspmu_validate_event(event->pmu, &fake_hw_events, event); +} + +static int arm_cspmu_event_init(struct perf_event *event) +{ + struct arm_cspmu *cspmu; + struct hw_perf_event *hwc = &event->hw; + + cspmu = to_arm_cspmu(event->pmu); + + if (event->attr.type != event->pmu->type) + return -ENOENT; + + /* + * Following other "uncore" PMUs, we do not support sampling mode or + * attach to a task (per-process mode). + */ + if (is_sampling_event(event)) { + dev_dbg(cspmu->pmu.dev, + "Can't support sampling events\n"); + return -EOPNOTSUPP; + } + + if (event->cpu < 0 || event->attach_state & PERF_ATTACH_TASK) { + dev_dbg(cspmu->pmu.dev, + "Can't support per-task counters\n"); + return -EINVAL; + } + + /* + * Make sure the CPU assignment is on one of the CPUs associated with + * this PMU. + */ + if (!cpumask_test_cpu(event->cpu, &cspmu->associated_cpus)) { + dev_dbg(cspmu->pmu.dev, + "Requested cpu is not associated with the PMU\n"); + return -EINVAL; + } + + /* Enforce the current active CPU to handle the events in this PMU. */ + event->cpu = cpumask_first(&cspmu->active_cpu); + if (event->cpu >= nr_cpu_ids) + return -EINVAL; + + if (!arm_cspmu_validate_group(event)) + return -EINVAL; + + /* + * The logical counter id is tracked with hw_perf_event.extra_reg.idx. + * The physical counter id is tracked with hw_perf_event.idx. + * We don't assign an index until we actually place the event onto + * hardware. Use -1 to signify that we haven't decided where to put it + * yet. + */ + hwc->idx = -1; + hwc->extra_reg.idx = -1; + hwc->config = cspmu->impl.ops.event_type(event); + + return 0; +} + +static inline u32 counter_offset(u32 reg_sz, u32 ctr_idx) +{ + return (PMEVCNTR_LO + (reg_sz * ctr_idx)); +} + +static void arm_cspmu_write_counter(struct perf_event *event, u64 val) +{ + u32 offset; + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + + if (use_64b_counter_reg(cspmu)) { + offset = counter_offset(sizeof(u64), event->hw.idx); + + if (cspmu->has_atomic_dword) + writeq(val, cspmu->base1 + offset); + else + lo_hi_writeq(val, cspmu->base1 + offset); + } else { + offset = counter_offset(sizeof(u32), event->hw.idx); + + writel(lower_32_bits(val), cspmu->base1 + offset); + } +} + +static u64 arm_cspmu_read_counter(struct perf_event *event) +{ + u32 offset; + const void __iomem *counter_addr; + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + + if (use_64b_counter_reg(cspmu)) { + offset = counter_offset(sizeof(u64), event->hw.idx); + counter_addr = cspmu->base1 + offset; + + return cspmu->has_atomic_dword ? + readq(counter_addr) : + read_reg64_hilohi(counter_addr, HILOHI_MAX_POLL); + } + + offset = counter_offset(sizeof(u32), event->hw.idx); + return readl(cspmu->base1 + offset); +} + +/* + * arm_cspmu_set_event_period: Set the period for the counter. + * + * To handle cases of extreme interrupt latency, we program + * the counter with half of the max count for the counters. + */ +static void arm_cspmu_set_event_period(struct perf_event *event) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + u64 val = counter_mask(cspmu) >> 1ULL; + + local64_set(&event->hw.prev_count, val); + arm_cspmu_write_counter(event, val); +} + +static void arm_cspmu_enable_counter(struct arm_cspmu *cspmu, int idx) +{ + u32 reg_id, reg_bit, inten_off, cnten_off; + + reg_id = COUNTER_TO_SET_CLR_ID(idx); + reg_bit = COUNTER_TO_SET_CLR_BIT(idx); + + inten_off = PMINTENSET + (4 * reg_id); + cnten_off = PMCNTENSET + (4 * reg_id); + + writel(BIT(reg_bit), cspmu->base0 + inten_off); + writel(BIT(reg_bit), cspmu->base0 + cnten_off); +} + +static void arm_cspmu_disable_counter(struct arm_cspmu *cspmu, int idx) +{ + u32 reg_id, reg_bit, inten_off, cnten_off; + + reg_id = COUNTER_TO_SET_CLR_ID(idx); + reg_bit = COUNTER_TO_SET_CLR_BIT(idx); + + inten_off = PMINTENCLR + (4 * reg_id); + cnten_off = PMCNTENCLR + (4 * reg_id); + + writel(BIT(reg_bit), cspmu->base0 + cnten_off); + writel(BIT(reg_bit), cspmu->base0 + inten_off); +} + +static void arm_cspmu_event_update(struct perf_event *event) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + u64 delta, prev, now; + + do { + prev = local64_read(&hwc->prev_count); + now = arm_cspmu_read_counter(event); + } while (local64_cmpxchg(&hwc->prev_count, prev, now) != prev); + + delta = (now - prev) & counter_mask(cspmu); + local64_add(delta, &event->count); +} + +static inline void arm_cspmu_set_event(struct arm_cspmu *cspmu, + struct hw_perf_event *hwc) +{ + u32 offset = PMEVTYPER + (4 * hwc->idx); + + writel(hwc->config, cspmu->base0 + offset); +} + +static void arm_cspmu_set_ev_filter(struct arm_cspmu *cspmu, + const struct perf_event *event) +{ + u32 filter = event->attr.config1 & ARM_CSPMU_FILTER_MASK; + u32 filter2 = event->attr.config2 & ARM_CSPMU_FILTER_MASK; + u32 offset = 4 * event->hw.idx; + + writel(filter, cspmu->base0 + PMEVFILTR + offset); + writel(filter2, cspmu->base0 + PMEVFILT2R + offset); +} + +static void arm_cspmu_set_cc_filter(struct arm_cspmu *cspmu, + const struct perf_event *event) +{ + u32 filter = event->attr.config1 & ARM_CSPMU_FILTER_MASK; + + writel(filter, cspmu->base0 + PMCCFILTR); +} + +static void arm_cspmu_start(struct perf_event *event, int pmu_flags) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + + /* We always reprogram the counter */ + if (pmu_flags & PERF_EF_RELOAD) + WARN_ON(!(hwc->state & PERF_HES_UPTODATE)); + + arm_cspmu_set_event_period(event); + + if (event->hw.extra_reg.idx == cspmu->cycle_counter_logical_idx) { + cspmu->impl.ops.set_cc_filter(cspmu, event); + } else { + arm_cspmu_set_event(cspmu, hwc); + cspmu->impl.ops.set_ev_filter(cspmu, event); + } + + hwc->state = 0; + + arm_cspmu_enable_counter(cspmu, hwc->idx); +} + +static void arm_cspmu_stop(struct perf_event *event, int pmu_flags) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + + if (hwc->state & PERF_HES_STOPPED) + return; + + arm_cspmu_disable_counter(cspmu, hwc->idx); + + if (cspmu->impl.ops.reset_ev_filter) + cspmu->impl.ops.reset_ev_filter(cspmu, event); + + arm_cspmu_event_update(event); + + hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; +} + +static inline u32 to_phys_idx(struct arm_cspmu *cspmu, u32 idx) +{ + return (idx == cspmu->cycle_counter_logical_idx) ? + ARM_CSPMU_CYCLE_CNTR_IDX : idx; +} + +static int arm_cspmu_add(struct perf_event *event, int flags) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events; + struct hw_perf_event *hwc = &event->hw; + int idx; + + if (WARN_ON_ONCE(!cpumask_test_cpu(smp_processor_id(), + &cspmu->associated_cpus))) + return -ENOENT; + + idx = arm_cspmu_get_event_idx(hw_events, event); + if (idx < 0) + return idx; + + hw_events->events[idx] = event; + hwc->idx = to_phys_idx(cspmu, idx); + hwc->extra_reg.idx = idx; + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; + + if (flags & PERF_EF_START) + arm_cspmu_start(event, PERF_EF_RELOAD); + + /* Propagate changes to the userspace mapping. */ + perf_event_update_userpage(event); + + return 0; +} + +static void arm_cspmu_del(struct perf_event *event, int flags) +{ + struct arm_cspmu *cspmu = to_arm_cspmu(event->pmu); + struct arm_cspmu_hw_events *hw_events = &cspmu->hw_events; + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->extra_reg.idx; + + arm_cspmu_stop(event, PERF_EF_UPDATE); + + hw_events->events[idx] = NULL; + + clear_bit(idx, hw_events->used_ctrs); + + perf_event_update_userpage(event); +} + +static void arm_cspmu_read(struct perf_event *event) +{ + arm_cspmu_event_update(event); +} + +static struct arm_cspmu *arm_cspmu_alloc(struct platform_device *pdev) +{ + struct acpi_apmt_node *apmt_node; + struct arm_cspmu *cspmu; + struct device *dev = &pdev->dev; + + cspmu = devm_kzalloc(dev, sizeof(*cspmu), GFP_KERNEL); + if (!cspmu) + return NULL; + + cspmu->dev = dev; + platform_set_drvdata(pdev, cspmu); + + apmt_node = arm_cspmu_apmt_node(dev); + if (apmt_node) { + cspmu->has_atomic_dword = apmt_node->flags & ACPI_APMT_FLAGS_ATOMIC; + } else { + u32 width = 0; + + device_property_read_u32(dev, "reg-io-width", &width); + cspmu->has_atomic_dword = (width == 8); + } + + return cspmu; +} + +static int arm_cspmu_init_mmio(struct arm_cspmu *cspmu) +{ + struct device *dev; + struct platform_device *pdev; + + dev = cspmu->dev; + pdev = to_platform_device(dev); + + /* Base address for page 0. */ + cspmu->base0 = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(cspmu->base0)) { + dev_err(dev, "ioremap failed for page-0 resource\n"); + return PTR_ERR(cspmu->base0); + } + + /* Base address for page 1 if supported. Otherwise point to page 0. */ + cspmu->base1 = cspmu->base0; + if (platform_get_resource(pdev, IORESOURCE_MEM, 1)) { + cspmu->base1 = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(cspmu->base1)) { + dev_err(dev, "ioremap failed for page-1 resource\n"); + return PTR_ERR(cspmu->base1); + } + } + + cspmu->pmcfgr = readl(cspmu->base0 + PMCFGR); + + cspmu->num_logical_ctrs = FIELD_GET(PMCFGR_N, cspmu->pmcfgr) + 1; + + cspmu->cycle_counter_logical_idx = ARM_CSPMU_MAX_HW_CNTRS; + + if (supports_cycle_counter(cspmu)) { + /* + * The last logical counter is mapped to cycle counter if + * there is a gap between regular and cycle counter. Otherwise, + * logical and physical have 1-to-1 mapping. + */ + cspmu->cycle_counter_logical_idx = + (cspmu->num_logical_ctrs <= ARM_CSPMU_CYCLE_CNTR_IDX) ? + cspmu->num_logical_ctrs - 1 : + ARM_CSPMU_CYCLE_CNTR_IDX; + } + + cspmu->num_set_clr_reg = + DIV_ROUND_UP(cspmu->num_logical_ctrs, + ARM_CSPMU_SET_CLR_COUNTER_NUM); + + cspmu->hw_events.events = + devm_kcalloc(dev, cspmu->num_logical_ctrs, + sizeof(*cspmu->hw_events.events), GFP_KERNEL); + + if (!cspmu->hw_events.events) + return -ENOMEM; + + return 0; +} + +static inline int arm_cspmu_get_reset_overflow(struct arm_cspmu *cspmu, + u32 *pmovs) +{ + int i; + u32 pmovclr_offset = PMOVSCLR; + u32 has_overflowed = 0; + + for (i = 0; i < cspmu->num_set_clr_reg; ++i) { + pmovs[i] = readl(cspmu->base1 + pmovclr_offset); + has_overflowed |= pmovs[i]; + writel(pmovs[i], cspmu->base1 + pmovclr_offset); + pmovclr_offset += sizeof(u32); + } + + return has_overflowed != 0; +} + +static irqreturn_t arm_cspmu_handle_irq(int irq_num, void *dev) +{ + int idx, has_overflowed; + struct perf_event *event; + struct arm_cspmu *cspmu = dev; + DECLARE_BITMAP(pmovs, ARM_CSPMU_MAX_HW_CNTRS); + bool handled = false; + + arm_cspmu_stop_counters(cspmu); + + has_overflowed = arm_cspmu_get_reset_overflow(cspmu, (u32 *)pmovs); + if (!has_overflowed) + goto done; + + for_each_set_bit(idx, cspmu->hw_events.used_ctrs, + cspmu->num_logical_ctrs) { + event = cspmu->hw_events.events[idx]; + + if (!event) + continue; + + if (!test_bit(event->hw.idx, pmovs)) + continue; + + arm_cspmu_event_update(event); + arm_cspmu_set_event_period(event); + + handled = true; + } + +done: + arm_cspmu_start_counters(cspmu); + return IRQ_RETVAL(handled); +} + +static int arm_cspmu_request_irq(struct arm_cspmu *cspmu) +{ + int irq, ret; + struct device *dev; + struct platform_device *pdev; + + dev = cspmu->dev; + pdev = to_platform_device(dev); + + /* Skip IRQ request if the PMU does not support overflow interrupt. */ + irq = platform_get_irq_optional(pdev, 0); + if (irq < 0) + return irq == -ENXIO ? 0 : irq; + + ret = devm_request_irq(dev, irq, arm_cspmu_handle_irq, + IRQF_NOBALANCING | IRQF_NO_THREAD, dev_name(dev), + cspmu); + if (ret) { + dev_err(dev, "Could not request IRQ %d\n", irq); + return ret; + } + + cspmu->irq = irq; + + return 0; +} + +#if defined(CONFIG_ACPI) && defined(CONFIG_ARM64) +#include <acpi/processor.h> + +static inline int arm_cspmu_find_cpu_container(int cpu, u32 container_uid) +{ + struct device *cpu_dev; + struct acpi_device *acpi_dev; + + cpu_dev = get_cpu_device(cpu); + if (!cpu_dev) + return -ENODEV; + + acpi_dev = ACPI_COMPANION(cpu_dev); + while (acpi_dev) { + if (acpi_dev_hid_uid_match(acpi_dev, ACPI_PROCESSOR_CONTAINER_HID, container_uid)) + return 0; + + acpi_dev = acpi_dev_parent(acpi_dev); + } + + return -ENODEV; +} + +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu) +{ + struct acpi_apmt_node *apmt_node; + int affinity_flag; + int cpu; + + apmt_node = arm_cspmu_apmt_node(cspmu->dev); + affinity_flag = apmt_node->flags & ACPI_APMT_FLAGS_AFFINITY; + + if (affinity_flag == ACPI_APMT_FLAGS_AFFINITY_PROC) { + for_each_possible_cpu(cpu) { + if (apmt_node->proc_affinity == + get_acpi_id_for_cpu(cpu)) { + cpumask_set_cpu(cpu, &cspmu->associated_cpus); + break; + } + } + } else { + for_each_possible_cpu(cpu) { + if (arm_cspmu_find_cpu_container( + cpu, apmt_node->proc_affinity)) + continue; + + cpumask_set_cpu(cpu, &cspmu->associated_cpus); + } + } + + return 0; +} +#else +static int arm_cspmu_acpi_get_cpus(struct arm_cspmu *cspmu) +{ + return -ENODEV; +} +#endif + +static int arm_cspmu_of_get_cpus(struct arm_cspmu *cspmu) +{ + struct of_phandle_iterator it; + int ret, cpu; + + of_for_each_phandle(&it, ret, dev_of_node(cspmu->dev), "cpus", NULL, 0) { + cpu = of_cpu_node_to_id(it.node); + if (cpu < 0) + continue; + cpumask_set_cpu(cpu, &cspmu->associated_cpus); + } + return ret == -ENOENT ? 0 : ret; +} + +static int arm_cspmu_get_cpus(struct arm_cspmu *cspmu) +{ + int ret = 0; + + if (arm_cspmu_apmt_node(cspmu->dev)) + ret = arm_cspmu_acpi_get_cpus(cspmu); + else if (device_property_present(cspmu->dev, "cpus")) + ret = arm_cspmu_of_get_cpus(cspmu); + else + cpumask_copy(&cspmu->associated_cpus, cpu_possible_mask); + + if (!ret && cpumask_empty(&cspmu->associated_cpus)) { + dev_dbg(cspmu->dev, "No cpu associated with the PMU\n"); + ret = -ENODEV; + } + return ret; +} + +static int arm_cspmu_register_pmu(struct arm_cspmu *cspmu) +{ + int ret, capabilities; + + ret = arm_cspmu_alloc_attr_groups(cspmu); + if (ret) + return ret; + + ret = cpuhp_state_add_instance(arm_cspmu_cpuhp_state, + &cspmu->cpuhp_node); + if (ret) + return ret; + + capabilities = PERF_PMU_CAP_NO_EXCLUDE; + if (cspmu->irq == 0) + capabilities |= PERF_PMU_CAP_NO_INTERRUPT; + + cspmu->pmu = (struct pmu){ + .task_ctx_nr = perf_invalid_context, + .module = cspmu->impl.module, + .parent = cspmu->dev, + .pmu_enable = arm_cspmu_enable, + .pmu_disable = arm_cspmu_disable, + .event_init = arm_cspmu_event_init, + .add = arm_cspmu_add, + .del = arm_cspmu_del, + .start = arm_cspmu_start, + .stop = arm_cspmu_stop, + .read = arm_cspmu_read, + .attr_groups = cspmu->attr_groups, + .capabilities = capabilities, + }; + + /* Hardware counter init */ + arm_cspmu_reset_counters(cspmu); + + ret = perf_pmu_register(&cspmu->pmu, cspmu->name, -1); + if (ret) { + cpuhp_state_remove_instance(arm_cspmu_cpuhp_state, + &cspmu->cpuhp_node); + } + + return ret; +} + +static int arm_cspmu_device_probe(struct platform_device *pdev) +{ + int ret; + struct arm_cspmu *cspmu; + + cspmu = arm_cspmu_alloc(pdev); + if (!cspmu) + return -ENOMEM; + + ret = arm_cspmu_init_mmio(cspmu); + if (ret) + return ret; + + ret = arm_cspmu_request_irq(cspmu); + if (ret) + return ret; + + ret = arm_cspmu_get_cpus(cspmu); + if (ret) + return ret; + + ret = arm_cspmu_init_impl_ops(cspmu); + if (ret) + return ret; + + ret = arm_cspmu_register_pmu(cspmu); + + /* Matches arm_cspmu_init_impl_ops() above. */ + if (cspmu->impl.module != THIS_MODULE) + module_put(cspmu->impl.module); + + return ret; +} + +static void arm_cspmu_device_remove(struct platform_device *pdev) +{ + struct arm_cspmu *cspmu = platform_get_drvdata(pdev); + + perf_pmu_unregister(&cspmu->pmu); + cpuhp_state_remove_instance(arm_cspmu_cpuhp_state, &cspmu->cpuhp_node); +} + +static const struct platform_device_id arm_cspmu_id[] = { + {DRVNAME, 0}, + { }, +}; +MODULE_DEVICE_TABLE(platform, arm_cspmu_id); + +static const struct of_device_id arm_cspmu_of_match[] = { + { .compatible = "arm,coresight-pmu" }, + {} +}; +MODULE_DEVICE_TABLE(of, arm_cspmu_of_match); + +static struct platform_driver arm_cspmu_driver = { + .driver = { + .name = DRVNAME, + .of_match_table = arm_cspmu_of_match, + .suppress_bind_attrs = true, + }, + .probe = arm_cspmu_device_probe, + .remove = arm_cspmu_device_remove, + .id_table = arm_cspmu_id, +}; + +static void arm_cspmu_set_active_cpu(int cpu, struct arm_cspmu *cspmu) +{ + cpumask_set_cpu(cpu, &cspmu->active_cpu); + if (cspmu->irq) + WARN_ON(irq_set_affinity(cspmu->irq, &cspmu->active_cpu)); +} + +static int arm_cspmu_cpu_online(unsigned int cpu, struct hlist_node *node) +{ + struct arm_cspmu *cspmu = + hlist_entry_safe(node, struct arm_cspmu, cpuhp_node); + + if (!cpumask_test_cpu(cpu, &cspmu->associated_cpus)) + return 0; + + /* If the PMU is already managed, there is nothing to do */ + if (!cpumask_empty(&cspmu->active_cpu)) + return 0; + + /* Use this CPU for event counting */ + arm_cspmu_set_active_cpu(cpu, cspmu); + + return 0; +} + +static int arm_cspmu_cpu_teardown(unsigned int cpu, struct hlist_node *node) +{ + unsigned int dst; + + struct arm_cspmu *cspmu = + hlist_entry_safe(node, struct arm_cspmu, cpuhp_node); + + /* Nothing to do if this CPU doesn't own the PMU */ + if (!cpumask_test_and_clear_cpu(cpu, &cspmu->active_cpu)) + return 0; + + /* Choose a new CPU to migrate ownership of the PMU to */ + dst = cpumask_any_and_but(&cspmu->associated_cpus, + cpu_online_mask, cpu); + if (dst >= nr_cpu_ids) + return 0; + + /* Use this CPU for event counting */ + perf_pmu_migrate_context(&cspmu->pmu, cpu, dst); + arm_cspmu_set_active_cpu(dst, cspmu); + + return 0; +} + +static int __init arm_cspmu_init(void) +{ + int ret; + + ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, + "perf/arm/cspmu:online", + arm_cspmu_cpu_online, + arm_cspmu_cpu_teardown); + if (ret < 0) + return ret; + arm_cspmu_cpuhp_state = ret; + return platform_driver_register(&arm_cspmu_driver); +} + +static void __exit arm_cspmu_exit(void) +{ + platform_driver_unregister(&arm_cspmu_driver); + cpuhp_remove_multi_state(arm_cspmu_cpuhp_state); +} + +int arm_cspmu_impl_register(const struct arm_cspmu_impl_match *impl_match) +{ + struct arm_cspmu_impl_match *match; + int ret = 0; + + match = arm_cspmu_impl_match_get(impl_match->pmiidr_val); + + if (match) { + mutex_lock(&arm_cspmu_lock); + + if (!match->impl_init_ops) { + match->module = impl_match->module; + match->impl_init_ops = impl_match->impl_init_ops; + } else { + /* Broken match table may contain non-unique entries */ + WARN(1, "arm_cspmu backend already registered for module: %s, pmiidr: 0x%x, mask: 0x%x\n", + match->module_name, + match->pmiidr_val, + match->pmiidr_mask); + + ret = -EINVAL; + } + + mutex_unlock(&arm_cspmu_lock); + + if (!ret) + ret = driver_attach(&arm_cspmu_driver.driver); + } else { + pr_err("arm_cspmu reg failed, unable to find a match for pmiidr: 0x%x\n", + impl_match->pmiidr_val); + + ret = -EINVAL; + } + + return ret; +} +EXPORT_SYMBOL_GPL(arm_cspmu_impl_register); + +static int arm_cspmu_match_device(struct device *dev, const void *match) +{ + struct arm_cspmu *cspmu = platform_get_drvdata(to_platform_device(dev)); + + return (cspmu && cspmu->impl.match == match) ? 1 : 0; +} + +void arm_cspmu_impl_unregister(const struct arm_cspmu_impl_match *impl_match) +{ + struct device *dev; + struct arm_cspmu_impl_match *match; + + match = arm_cspmu_impl_match_get(impl_match->pmiidr_val); + + if (WARN_ON(!match)) + return; + + /* Unbind the driver from all matching backend devices. */ + while ((dev = driver_find_device(&arm_cspmu_driver.driver, NULL, + match, arm_cspmu_match_device))) { + device_release_driver(dev); + put_device(dev); + } + + mutex_lock(&arm_cspmu_lock); + + match->module = NULL; + match->impl_init_ops = NULL; + + mutex_unlock(&arm_cspmu_lock); +} +EXPORT_SYMBOL_GPL(arm_cspmu_impl_unregister); + +module_init(arm_cspmu_init); +module_exit(arm_cspmu_exit); + +MODULE_DESCRIPTION("ARM CoreSight Architecture Performance Monitor Driver"); +MODULE_LICENSE("GPL v2"); |
