diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/Makefile | 1 | ||||
| -rw-r--r-- | drivers/perf/Kconfig | 15 | ||||
| -rw-r--r-- | drivers/perf/Makefile | 1 | ||||
| -rw-r--r-- | drivers/perf/arm_pmu.c | 921 |
5 files changed, 940 insertions, 0 deletions
diff --git a/drivers/Kconfig b/drivers/Kconfig index 6e973b8e3a3b..3497485f5eab 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -176,6 +176,8 @@ source "drivers/powercap/Kconfig" source "drivers/mcb/Kconfig" +source "drivers/perf/Kconfig" + source "drivers/ras/Kconfig" source "drivers/thunderbolt/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index b64b49f6e01b..f245f2291b8a 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -161,6 +161,7 @@ obj-$(CONFIG_NTB) += ntb/ obj-$(CONFIG_FMC) += fmc/ obj-$(CONFIG_POWERCAP) += powercap/ obj-$(CONFIG_MCB) += mcb/ +obj-$(CONFIG_PERF_EVENTS) += perf/ obj-$(CONFIG_RAS) += ras/ obj-$(CONFIG_THUNDERBOLT) += thunderbolt/ obj-$(CONFIG_CORESIGHT) += hwtracing/coresight/ diff --git a/drivers/perf/Kconfig b/drivers/perf/Kconfig new file mode 100644 index 000000000000..d9de36ee165d --- /dev/null +++ b/drivers/perf/Kconfig @@ -0,0 +1,15 @@ +# +# Performance Monitor Drivers +# + +menu "Performance monitor support" + +config ARM_PMU + depends on PERF_EVENTS && ARM + bool "ARM PMU framework" + default y + help + Say y if you want to use CPU performance monitors on ARM-based + systems. + +endmenu diff --git a/drivers/perf/Makefile b/drivers/perf/Makefile new file mode 100644 index 000000000000..acd2397ded94 --- /dev/null +++ b/drivers/perf/Makefile @@ -0,0 +1 @@ +obj-$(CONFIG_ARM_PMU) += arm_pmu.o diff --git a/drivers/perf/arm_pmu.c b/drivers/perf/arm_pmu.c new file mode 100644 index 000000000000..2365a32a595e --- /dev/null +++ b/drivers/perf/arm_pmu.c @@ -0,0 +1,921 @@ +#undef DEBUG + +/* + * ARM performance counter support. + * + * Copyright (C) 2009 picoChip Designs, Ltd., Jamie Iles + * Copyright (C) 2010 ARM Ltd., Will Deacon <will.deacon@arm.com> + * + * This code is based on the sparc64 perf event code, which is in turn based + * on the x86 code. + */ +#define pr_fmt(fmt) "hw perfevents: " fmt + +#include <linux/bitmap.h> +#include <linux/cpumask.h> +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/of_device.h> +#include <linux/perf/arm_pmu.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/irq.h> +#include <linux/irqdesc.h> + +#include <asm/cputype.h> +#include <asm/irq_regs.h> + +static int +armpmu_map_cache_event(const unsigned (*cache_map) + [PERF_COUNT_HW_CACHE_MAX] + [PERF_COUNT_HW_CACHE_OP_MAX] + [PERF_COUNT_HW_CACHE_RESULT_MAX], + u64 config) +{ + unsigned int cache_type, cache_op, cache_result, ret; + + cache_type = (config >> 0) & 0xff; + if (cache_type >= PERF_COUNT_HW_CACHE_MAX) + return -EINVAL; + + cache_op = (config >> 8) & 0xff; + if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX) + return -EINVAL; + + cache_result = (config >> 16) & 0xff; + if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX) + return -EINVAL; + + ret = (int)(*cache_map)[cache_type][cache_op][cache_result]; + + if (ret == CACHE_OP_UNSUPPORTED) + return -ENOENT; + + return ret; +} + +static int +armpmu_map_hw_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config) +{ + int mapping; + + if (config >= PERF_COUNT_HW_MAX) + return -EINVAL; + + mapping = (*event_map)[config]; + return mapping == HW_OP_UNSUPPORTED ? -ENOENT : mapping; +} + +static int +armpmu_map_raw_event(u32 raw_event_mask, u64 config) +{ + return (int)(config & raw_event_mask); +} + +int +armpmu_map_event(struct perf_event *event, + const unsigned (*event_map)[PERF_COUNT_HW_MAX], + const unsigned (*cache_map) + [PERF_COUNT_HW_CACHE_MAX] + [PERF_COUNT_HW_CACHE_OP_MAX] + [PERF_COUNT_HW_CACHE_RESULT_MAX], + u32 raw_event_mask) +{ + u64 config = event->attr.config; + int type = event->attr.type; + + if (type == event->pmu->type) + return armpmu_map_raw_event(raw_event_mask, config); + + switch (type) { + case PERF_TYPE_HARDWARE: + return armpmu_map_hw_event(event_map, config); + case PERF_TYPE_HW_CACHE: + return armpmu_map_cache_event(cache_map, config); + case PERF_TYPE_RAW: + return armpmu_map_raw_event(raw_event_mask, config); + } + + return -ENOENT; +} + +int armpmu_event_set_period(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + s64 left = local64_read(&hwc->period_left); + s64 period = hwc->sample_period; + int ret = 0; + + if (unlikely(left <= -period)) { + left = period; + local64_set(&hwc->period_left, left); + hwc->last_period = period; + ret = 1; + } + + if (unlikely(left <= 0)) { + left += period; + local64_set(&hwc->period_left, left); + hwc->last_period = period; + ret = 1; + } + + /* + * Limit the maximum period to prevent the counter value + * from overtaking the one we are about to program. In + * effect we are reducing max_period to account for + * interrupt latency (and we are being very conservative). + */ + if (left > (armpmu->max_period >> 1)) + left = armpmu->max_period >> 1; + + local64_set(&hwc->prev_count, (u64)-left); + + armpmu->write_counter(event, (u64)(-left) & 0xffffffff); + + perf_event_update_userpage(event); + + return ret; +} + +u64 armpmu_event_update(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + u64 delta, prev_raw_count, new_raw_count; + +again: + prev_raw_count = local64_read(&hwc->prev_count); + new_raw_count = armpmu->read_counter(event); + + if (local64_cmpxchg(&hwc->prev_count, prev_raw_count, + new_raw_count) != prev_raw_count) + goto again; + + delta = (new_raw_count - prev_raw_count) & armpmu->max_period; + + local64_add(delta, &event->count); + local64_sub(delta, &hwc->period_left); + + return new_raw_count; +} + +static void +armpmu_read(struct perf_event *event) +{ + armpmu_event_update(event); +} + +static void +armpmu_stop(struct perf_event *event, int flags) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + + /* + * ARM pmu always has to update the counter, so ignore + * PERF_EF_UPDATE, see comments in armpmu_start(). + */ + if (!(hwc->state & PERF_HES_STOPPED)) { + armpmu->disable(event); + armpmu_event_update(event); + hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE; + } +} + +static void armpmu_start(struct perf_event *event, int flags) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + + /* + * ARM pmu always has to reprogram the period, so ignore + * PERF_EF_RELOAD, see the comment below. + */ + if (flags & PERF_EF_RELOAD) + WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE)); + + hwc->state = 0; + /* + * Set the period again. Some counters can't be stopped, so when we + * were stopped we simply disabled the IRQ source and the counter + * may have been left counting. If we don't do this step then we may + * get an interrupt too soon or *way* too late if the overflow has + * happened since disabling. + */ + armpmu_event_set_period(event); + armpmu->enable(event); +} + +static void +armpmu_del(struct perf_event *event, int flags) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events); + struct hw_perf_event *hwc = &event->hw; + int idx = hwc->idx; + + armpmu_stop(event, PERF_EF_UPDATE); + hw_events->events[idx] = NULL; + clear_bit(idx, hw_events->used_mask); + if (armpmu->clear_event_idx) + armpmu->clear_event_idx(hw_events, event); + + perf_event_update_userpage(event); +} + +static int +armpmu_add(struct perf_event *event, int flags) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events); + struct hw_perf_event *hwc = &event->hw; + int idx; + int err = 0; + + /* An event following a process won't be stopped earlier */ + if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus)) + return -ENOENT; + + perf_pmu_disable(event->pmu); + + /* If we don't have a space for the counter then finish early. */ + idx = armpmu->get_event_idx(hw_events, event); + if (idx < 0) { + err = idx; + goto out; + } + + /* + * If there is an event in the counter we are going to use then make + * sure it is disabled. + */ + event->hw.idx = idx; + armpmu->disable(event); + hw_events->events[idx] = event; + + hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE; + if (flags & PERF_EF_START) + armpmu_start(event, PERF_EF_RELOAD); + + /* Propagate our changes to the userspace mapping. */ + perf_event_update_userpage(event); + +out: + perf_pmu_enable(event->pmu); + return err; +} + +static int +validate_event(struct pmu *pmu, struct pmu_hw_events *hw_events, + struct perf_event *event) +{ + struct arm_pmu *armpmu; + + if (is_software_event(event)) + return 1; + + /* + * Reject groups spanning multiple HW PMUs (e.g. CPU + CCI). The + * core perf code won't check that the pmu->ctx == leader->ctx + * until after pmu->event_init(event). + */ + if (event->pmu != pmu) + return 0; + + if (event->state < PERF_EVENT_STATE_OFF) + return 1; + + if (event->state == PERF_EVENT_STATE_OFF && !event->attr.enable_on_exec) + return 1; + + armpmu = to_arm_pmu(event->pmu); + return armpmu->get_event_idx(hw_events, event) >= 0; +} + +static int +validate_group(struct perf_event *event) +{ + struct perf_event *sibling, *leader = event->group_leader; + struct pmu_hw_events fake_pmu; + + /* + * Initialise the fake PMU. We only need to populate the + * used_mask for the purposes of validation. + */ + memset(&fake_pmu.used_mask, 0, sizeof(fake_pmu.used_mask)); + + if (!validate_event(event->pmu, &fake_pmu, leader)) + return -EINVAL; + + list_for_each_entry(sibling, &leader->sibling_list, group_entry) { + if (!validate_event(event->pmu, &fake_pmu, sibling)) + return -EINVAL; + } + + if (!validate_event(event->pmu, &fake_pmu, event)) + return -EINVAL; + + return 0; +} + +static irqreturn_t armpmu_dispatch_irq(int irq, void *dev) +{ + struct arm_pmu *armpmu; + struct platform_device *plat_device; + struct arm_pmu_platdata *plat; + int ret; + u64 start_clock, finish_clock; + + /* + * we request the IRQ with a (possibly percpu) struct arm_pmu**, but + * the handlers expect a struct arm_pmu*. The percpu_irq framework will + * do any necessary shifting, we just need to perform the first + * dereference. + */ + armpmu = *(void **)dev; + plat_device = armpmu->plat_device; + plat = dev_get_platdata(&plat_device->dev); + + start_clock = sched_clock(); + if (plat && plat->handle_irq) + ret = plat->handle_irq(irq, armpmu, armpmu->handle_irq); + else + ret = armpmu->handle_irq(irq, armpmu); + finish_clock = sched_clock(); + + perf_sample_event_took(finish_clock - start_clock); + return ret; +} + +static void +armpmu_release_hardware(struct arm_pmu *armpmu) +{ + armpmu->free_irq(armpmu); +} + +static int +armpmu_reserve_hardware(struct arm_pmu *armpmu) +{ + int err = armpmu->request_irq(armpmu, armpmu_dispatch_irq); + if (err) { + armpmu_release_hardware(armpmu); + return err; + } + + return 0; +} + +static void +hw_perf_event_destroy(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + atomic_t *active_events = &armpmu->active_events; + struct mutex *pmu_reserve_mutex = &armpmu->reserve_mutex; + + if (atomic_dec_and_mutex_lock(active_events, pmu_reserve_mutex)) { + armpmu_release_hardware(armpmu); + mutex_unlock(pmu_reserve_mutex); + } +} + +static int +event_requires_mode_exclusion(struct perf_event_attr *attr) +{ + return attr->exclude_idle || attr->exclude_user || + attr->exclude_kernel || attr->exclude_hv; +} + +static int +__hw_perf_event_init(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + struct hw_perf_event *hwc = &event->hw; + int mapping; + + mapping = armpmu->map_event(event); + + if (mapping < 0) { + pr_debug("event %x:%llx not supported\n", event->attr.type, + event->attr.config); + return mapping; + } + + /* + * 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. For SMP systems, each core has it's own PMU so we can't do any + * clever allocation or constraints checking at this point. + */ + hwc->idx = -1; + hwc->config_base = 0; + hwc->config = 0; + hwc->event_base = 0; + + /* + * Check whether we need to exclude the counter from certain modes. + */ + if ((!armpmu->set_event_filter || + armpmu->set_event_filter(hwc, &event->attr)) && + event_requires_mode_exclusion(&event->attr)) { + pr_debug("ARM performance counters do not support " + "mode exclusion\n"); + return -EOPNOTSUPP; + } + + /* + * Store the event encoding into the config_base field. + */ + hwc->config_base |= (unsigned long)mapping; + + if (!is_sampling_event(event)) { + /* + * For non-sampling runs, limit the sample_period to half + * of the counter width. That way, the new counter value + * is far less likely to overtake the previous one unless + * you have some serious IRQ latency issues. + */ + hwc->sample_period = armpmu->max_period >> 1; + hwc->last_period = hwc->sample_period; + local64_set(&hwc->period_left, hwc->sample_period); + } + + if (event->group_leader != event) { + if (validate_group(event) != 0) + return -EINVAL; + } + + return 0; +} + +static int armpmu_event_init(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + int err = 0; + atomic_t *active_events = &armpmu->active_events; + + /* + * Reject CPU-affine events for CPUs that are of a different class to + * that which this PMU handles. Process-following events (where + * event->cpu == -1) can be migrated between CPUs, and thus we have to + * reject them later (in armpmu_add) if they're scheduled on a + * different class of CPU. + */ + if (event->cpu != -1 && + !cpumask_test_cpu(event->cpu, &armpmu->supported_cpus)) + return -ENOENT; + + /* does not support taken branch sampling */ + if (has_branch_stack(event)) + return -EOPNOTSUPP; + + if (armpmu->map_event(event) == -ENOENT) + return -ENOENT; + + event->destroy = hw_perf_event_destroy; + + if (!atomic_inc_not_zero(active_events)) { + mutex_lock(&armpmu->reserve_mutex); + if (atomic_read(active_events) == 0) + err = armpmu_reserve_hardware(armpmu); + + if (!err) + atomic_inc(active_events); + mutex_unlock(&armpmu->reserve_mutex); + } + + if (err) + return err; + + err = __hw_perf_event_init(event); + if (err) + hw_perf_event_destroy(event); + + return err; +} + +static void armpmu_enable(struct pmu *pmu) +{ + struct arm_pmu *armpmu = to_arm_pmu(pmu); + struct pmu_hw_events *hw_events = this_cpu_ptr(armpmu->hw_events); + int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events); + + /* For task-bound events we may be called on other CPUs */ + if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus)) + return; + + if (enabled) + armpmu->start(armpmu); +} + +static void armpmu_disable(struct pmu *pmu) +{ + struct arm_pmu *armpmu = to_arm_pmu(pmu); + + /* For task-bound events we may be called on other CPUs */ + if (!cpumask_test_cpu(smp_processor_id(), &armpmu->supported_cpus)) + return; + + armpmu->stop(armpmu); +} + +/* + * In heterogeneous systems, events are specific to a particular + * microarchitecture, and aren't suitable for another. Thus, only match CPUs of + * the same microarchitecture. + */ +static int armpmu_filter_match(struct perf_event *event) +{ + struct arm_pmu *armpmu = to_arm_pmu(event->pmu); + unsigned int cpu = smp_processor_id(); + return cpumask_test_cpu(cpu, &armpmu->supported_cpus); +} + +static void armpmu_init(struct arm_pmu *armpmu) +{ + atomic_set(&armpmu->active_events, 0); + mutex_init(&armpmu->reserve_mutex); + + armpmu->pmu = (struct pmu) { + .pmu_enable = armpmu_enable, + .pmu_disable = armpmu_disable, + .event_init = armpmu_event_init, + .add = armpmu_add, + .del = armpmu_del, + .start = armpmu_start, + .stop = armpmu_stop, + .read = armpmu_read, + .filter_match = armpmu_filter_match, + }; +} + +int armpmu_register(struct arm_pmu *armpmu, int type) +{ + armpmu_init(armpmu); + pr_info("enabled with %s PMU driver, %d counters available\n", + armpmu->name, armpmu->num_events); + return perf_pmu_register(&armpmu->pmu, armpmu->name, type); +} + +/* Set at runtime when we know what CPU type we are. */ +static struct arm_pmu *__oprofile_cpu_pmu; + +/* + * Despite the names, these two functions are CPU-specific and are used + * by the OProfile/perf code. + */ +const char *perf_pmu_name(void) +{ + if (!__oprofile_cpu_pmu) + return NULL; + + return __oprofile_cpu_pmu->name; +} +EXPORT_SYMBOL_GPL(perf_pmu_name); + +int perf_num_counters(void) +{ + int max_events = 0; + + if (__oprofile_cpu_pmu != NULL) + max_events = __oprofile_cpu_pmu->num_events; + + return max_events; +} +EXPORT_SYMBOL_GPL(perf_num_counters); + +static void cpu_pmu_enable_percpu_irq(void *data) +{ + int irq = *(int *)data; + + enable_percpu_irq(irq, IRQ_TYPE_NONE); +} + +static void cpu_pmu_disable_percpu_irq(void *data) +{ + int irq = *(int *)data; + + disable_percpu_irq(irq); +} + +static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu) +{ + int i, irq, irqs; + struct platform_device *pmu_device = cpu_pmu->plat_device; + struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events; + + irqs = min(pmu_device->num_resources, num_possible_cpus()); + + irq = platform_get_irq(pmu_device, 0); + if (irq >= 0 && irq_is_percpu(irq)) { + on_each_cpu(cpu_pmu_disable_percpu_irq, &irq, 1); + free_percpu_irq(irq, &hw_events->percpu_pmu); + } else { + for (i = 0; i < irqs; ++i) { + int cpu = i; + + if (cpu_pmu->irq_affinity) + cpu = cpu_pmu->irq_affinity[i]; + + if (!cpumask_test_and_clear_cpu(cpu, &cpu_pmu->active_irqs)) + continue; + irq = platform_get_irq(pmu_device, i); + if (irq >= 0) + free_irq(irq, per_cpu_ptr(&hw_events->percpu_pmu, cpu)); + } + } +} + +static int cpu_pmu_request_irq(struct arm_pmu *cpu_pmu, irq_handler_t handler) +{ + int i, err, irq, irqs; + struct platform_device *pmu_device = cpu_pmu->plat_device; + struct pmu_hw_events __percpu *hw_events = cpu_pmu->hw_events; + + if (!pmu_device) + return -ENODEV; + + irqs = min(pmu_device->num_resources, num_possible_cpus()); + if (irqs < 1) { + pr_warn_once("perf/ARM: No irqs for PMU defined, sampling events not supported\n"); + return 0; + } + + irq = platform_get_irq(pmu_device, 0); + if (irq >= 0 && irq_is_percpu(irq)) { + err = request_percpu_irq(irq, handler, "arm-pmu", + &hw_events->percpu_pmu); + if (err) { + pr_err("unable to request IRQ%d for ARM PMU counters\n", + irq); + return err; + } + on_each_cpu(cpu_pmu_enable_percpu_irq, &irq, 1); + } else { + for (i = 0; i < irqs; ++i) { + int cpu = i; + + err = 0; + irq = platform_get_irq(pmu_device, i); + if (irq < 0) + continue; + + if (cpu_pmu->irq_affinity) + cpu = cpu_pmu->irq_affinity[i]; + + /* + * If we have a single PMU interrupt that we can't shift, + * assume that we're running on a uniprocessor machine and + * continue. Otherwise, continue without this interrupt. + */ + if (irq_set_affinity(irq, cpumask_of(cpu)) && irqs > 1) { + pr_warn("unable to set irq affinity (irq=%d, cpu=%u)\n", + irq, cpu); + continue; + } + + err = request_irq(irq, handler, + IRQF_NOBALANCING | IRQF_NO_THREAD, "arm-pmu", + per_cpu_ptr(&hw_events->percpu_pmu, cpu)); + if (err) { + pr_err("unable to request IRQ%d for ARM PMU counters\n", + irq); + return err; + } + + cpumask_set_cpu(cpu, &cpu_pmu->active_irqs); + } + } + + return 0; +} + +/* + * PMU hardware loses all context when a CPU goes offline. + * When a CPU is hotplugged back in, since some hardware registers are + * UNKNOWN at reset, the PMU must be explicitly reset to avoid reading + * junk values out of them. + */ +static int cpu_pmu_notify(struct notifier_block *b, unsigned long action, + void *hcpu) +{ + int cpu = (unsigned long)hcpu; + struct arm_pmu *pmu = container_of(b, struct arm_pmu, hotplug_nb); + + if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING) + return NOTIFY_DONE; + + if (!cpumask_test_cpu(cpu, &pmu->supported_cpus)) + return NOTIFY_DONE; + + if (pmu->reset) + pmu->reset(pmu); + else + return NOTIFY_DONE; + + return NOTIFY_OK; +} + +static int cpu_pmu_init(struct arm_pmu *cpu_pmu) +{ + int err; + int cpu; + struct pmu_hw_events __percpu *cpu_hw_events; + + cpu_hw_events = alloc_percpu(struct pmu_hw_events); + if (!cpu_hw_events) + return -ENOMEM; + + cpu_pmu->hotplug_nb.notifier_call = cpu_pmu_notify; + err = register_cpu_notifier(&cpu_pmu->hotplug_nb); + if (err) + goto out_hw_events; + + for_each_possible_cpu(cpu) { + struct pmu_hw_events *events = per_cpu_ptr(cpu_hw_events, cpu); + raw_spin_lock_init(&events->pmu_lock); + events->percpu_pmu = cpu_pmu; + } + + cpu_pmu->hw_events = cpu_hw_events; + cpu_pmu->request_irq = cpu_pmu_request_irq; + cpu_pmu->free_irq = cpu_pmu_free_irq; + + /* Ensure the PMU has sane values out of reset. */ + if (cpu_pmu->reset) + on_each_cpu_mask(&cpu_pmu->supported_cpus, cpu_pmu->reset, + cpu_pmu, 1); + + /* If no interrupts available, set the corresponding capability flag */ + if (!platform_get_irq(cpu_pmu->plat_device, 0)) + cpu_pmu->pmu.capabilities |= PERF_PMU_CAP_NO_INTERRUPT; + + return 0; + +out_hw_events: + free_percpu(cpu_hw_events); + return err; +} + +static void cpu_pmu_destroy(struct arm_pmu *cpu_pmu) +{ + unregister_cpu_notifier(&cpu_pmu->hotplug_nb); + free_percpu(cpu_pmu->hw_events); +} + +/* + * CPU PMU identification and probing. + */ +static int probe_current_pmu(struct arm_pmu *pmu, + const struct pmu_probe_info *info) +{ + int cpu = get_cpu(); + unsigned int cpuid = read_cpuid_id(); + int ret = -ENODEV; + + pr_info("probing PMU on CPU %d\n", cpu); + + for (; info->init != NULL; info++) { + if ((cpuid & info->mask) != info->cpuid) + continue; + ret = info->init(pmu); + break; + } + + put_cpu(); + return ret; +} + +static int of_pmu_irq_cfg(struct arm_pmu *pmu) +{ + int *irqs, i = 0; + bool using_spi = false; + struct platform_device *pdev = pmu->plat_device; + + irqs = kcalloc(pdev->num_resources, sizeof(*irqs), GFP_KERNEL); + if (!irqs) + return -ENOMEM; + + do { + struct device_node *dn; + int cpu, irq; + + /* See if we have an affinity entry */ + dn = of_parse_phandle(pdev->dev.of_node, "interrupt-affinity", i); + if (!dn) + break; + + /* Check the IRQ type and prohibit a mix of PPIs and SPIs */ + irq = platform_get_irq(pdev, i); + if (irq >= 0) { + bool spi = !irq_is_percpu(irq); + + if (i > 0 && spi != using_spi) { + pr_err("PPI/SPI IRQ type mismatch for %s!\n", + dn->name); + kfree(irqs); + return -EINVAL; + } + + using_spi = spi; + } + + /* Now look up the logical CPU number */ + for_each_possible_cpu(cpu) + if (dn == of_cpu_device_node_get(cpu)) + break; + + if (cpu >= nr_cpu_ids) { + pr_warn("Failed to find logical CPU for %s\n", + dn->name); + of_node_put(dn); + cpumask_setall(&pmu->supported_cpus); + break; + } + of_node_put(dn); + + /* For SPIs, we need to track the affinity per IRQ */ + if (using_spi) { + if (i >= pdev->num_resources) { + of_node_put(dn); + break; + } + + irqs[i] = cpu; + } + + /* Keep track of the CPUs containing this PMU type */ + cpumask_set_cpu(cpu, &pmu->supported_cpus); + of_node_put(dn); + i++; + } while (1); + + /* If we didn't manage to parse anything, claim to support all CPUs */ + if (cpumask_weight(&pmu->supported_cpus) == 0) + cpumask_setall(&pmu->supported_cpus); + + /* If we matched up the IRQ affinities, use them to route the SPIs */ + if (using_spi && i == pdev->num_resources) + pmu->irq_affinity = irqs; + else + kfree(irqs); + + return 0; +} + +int arm_pmu_device_probe(struct platform_device *pdev, + const struct of_device_id *of_table, + const struct pmu_probe_info *probe_table) +{ + const struct of_device_id *of_id; + const int (*init_fn)(struct arm_pmu *); + struct device_node *node = pdev->dev.of_node; + struct arm_pmu *pmu; + int ret = -ENODEV; + + pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL); + if (!pmu) { + pr_info("failed to allocate PMU device!\n"); + return -ENOMEM; + } + + if (!__oprofile_cpu_pmu) + __oprofile_cpu_pmu = pmu; + + pmu->plat_device = pdev; + + if (node && (of_id = of_match_node(of_table, pdev->dev.of_node))) { + init_fn = of_id->data; + + ret = of_pmu_irq_cfg(pmu); + if (!ret) + ret = init_fn(pmu); + } else { + ret = probe_current_pmu(pmu, probe_table); + cpumask_setall(&pmu->supported_cpus); + } + + if (ret) { + pr_info("failed to probe PMU!\n"); + goto out_free; + } + + ret = cpu_pmu_init(pmu); + if (ret) + goto out_free; + + ret = armpmu_register(pmu, -1); + if (ret) + goto out_destroy; + + return 0; + +out_destroy: + cpu_pmu_destroy(pmu); +out_free: + pr_info("failed to register PMU devices!\n"); + kfree(pmu); + return ret; +} |