/* * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Copyright (C) 2012 ARM Limited * * Author: Will Deacon <will.deacon@arm.com> */ #define pr_fmt(fmt) "CPU PMU: " fmt #include <linux/bitmap.h> #include <linux/export.h> #include <linux/kernel.h> #include <linux/of.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> #include <asm/pmu.h> /* Set at runtime when we know what CPU type we are. */ static struct arm_pmu *cpu_pmu; static DEFINE_PER_CPU(struct arm_pmu *, percpu_pmu); static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events); static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask); static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events); /* * Despite the names, these two functions are CPU-specific and are used * by the OProfile/perf code. */ const char *perf_pmu_name(void) { if (!cpu_pmu) return NULL; return cpu_pmu->name; } EXPORT_SYMBOL_GPL(perf_pmu_name); int perf_num_counters(void) { int max_events = 0; if (cpu_pmu != NULL) max_events = cpu_pmu->num_events; return max_events; } EXPORT_SYMBOL_GPL(perf_num_counters); /* Include the PMU-specific implementations. */ #include "perf_event_xscale.c" #include "perf_event_v6.c" #include "perf_event_v7.c" static struct pmu_hw_events *cpu_pmu_get_cpu_events(void) { return this_cpu_ptr(&cpu_hw_events); } 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; 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, &percpu_pmu); } else { for (i = 0; i < irqs; ++i) { if (!cpumask_test_and_clear_cpu(i, &cpu_pmu->active_irqs)) continue; irq = platform_get_irq(pmu_device, i); if (irq >= 0) free_irq(irq, cpu_pmu); } } } 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; if (!pmu_device) return -ENODEV; irqs = min(pmu_device->num_resources, num_possible_cpus()); if (irqs < 1) { printk_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", &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) { err = 0; irq = platform_get_irq(pmu_device, i); if (irq < 0) continue; /* * 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(i)) && irqs > 1) { pr_warn("unable to set irq affinity (irq=%d, cpu=%u)\n", irq, i); continue; } err = request_irq(irq, handler, IRQF_NOBALANCING | IRQF_NO_THREAD, "arm-pmu", cpu_pmu); if (err) { pr_err("unable to request IRQ%d for ARM PMU counters\n", irq); return err; } cpumask_set_cpu(i, &cpu_pmu->active_irqs); } } return 0; } static void cpu_pmu_init(struct arm_pmu *cpu_pmu) { int cpu; for_each_possible_cpu(cpu) { struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu); events->events = per_cpu(hw_events, cpu); events->used_mask = per_cpu(used_mask, cpu); raw_spin_lock_init(&events->pmu_lock); per_cpu(percpu_pmu, cpu) = cpu_pmu; } cpu_pmu->get_hw_events = cpu_pmu_get_cpu_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(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; } /* * 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) { if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING) return NOTIFY_DONE; if (cpu_pmu && cpu_pmu->reset) cpu_pmu->reset(cpu_pmu); else return NOTIFY_DONE; return NOTIFY_OK; } static struct notifier_block cpu_pmu_hotplug_notifier = { .notifier_call = cpu_pmu_notify, }; /* * PMU platform driver and devicetree bindings. */ static struct of_device_id cpu_pmu_of_device_ids[] = { {.compatible = "arm,cortex-a17-pmu", .data = armv7_a17_pmu_init}, {.compatible = "arm,cortex-a15-pmu", .data = armv7_a15_pmu_init}, {.compatible = "arm,cortex-a12-pmu", .data = armv7_a12_pmu_init}, {.compatible = "arm,cortex-a9-pmu", .data = armv7_a9_pmu_init}, {.compatible = "arm,cortex-a8-pmu", .data = armv7_a8_pmu_init}, {.compatible = "arm,cortex-a7-pmu", .data = armv7_a7_pmu_init}, {.compatible = "arm,cortex-a5-pmu", .data = armv7_a5_pmu_init}, {.compatible = "arm,arm11mpcore-pmu", .data = armv6mpcore_pmu_init}, {.compatible = "arm,arm1176-pmu", .data = armv6_1176_pmu_init}, {.compatible = "arm,arm1136-pmu", .data = armv6_1136_pmu_init}, {.compatible = "qcom,krait-pmu", .data = krait_pmu_init}, {}, }; static struct platform_device_id cpu_pmu_plat_device_ids[] = { {.name = "arm-pmu"}, {.name = "armv6-pmu"}, {.name = "armv7-pmu"}, {.name = "xscale-pmu"}, {}, }; /* * CPU PMU identification and probing. */ static int probe_current_pmu(struct arm_pmu *pmu) { int cpu = get_cpu(); int ret = -ENODEV; pr_info("probing PMU on CPU %d\n", cpu); switch (read_cpuid_part()) { /* ARM Ltd CPUs. */ case ARM_CPU_PART_ARM1136: ret = armv6_1136_pmu_init(pmu); break; case ARM_CPU_PART_ARM1156: ret = armv6_1156_pmu_init(pmu); break; case ARM_CPU_PART_ARM1176: ret = armv6_1176_pmu_init(pmu); break; case ARM_CPU_PART_ARM11MPCORE: ret = armv6mpcore_pmu_init(pmu); break; case ARM_CPU_PART_CORTEX_A8: ret = armv7_a8_pmu_init(pmu); break; case ARM_CPU_PART_CORTEX_A9: ret = armv7_a9_pmu_init(pmu); break; default: if (read_cpuid_implementor() == ARM_CPU_IMP_INTEL) { switch (xscale_cpu_arch_version()) { case ARM_CPU_XSCALE_ARCH_V1: ret = xscale1pmu_init(pmu); break; case ARM_CPU_XSCALE_ARCH_V2: ret = xscale2pmu_init(pmu); break; } } break; } put_cpu(); return ret; } static int cpu_pmu_device_probe(struct platform_device *pdev) { 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; if (cpu_pmu) { pr_info("attempt to register multiple PMU devices!"); return -ENOSPC; } pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL); if (!pmu) { pr_info("failed to allocate PMU device!"); return -ENOMEM; } cpu_pmu = pmu; cpu_pmu->plat_device = pdev; if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) { init_fn = of_id->data; ret = init_fn(pmu); } else { ret = probe_current_pmu(pmu); } if (ret) { pr_info("failed to probe PMU!"); goto out_free; } cpu_pmu_init(cpu_pmu); ret = armpmu_register(cpu_pmu, PERF_TYPE_RAW); if (!ret) return 0; out_free: pr_info("failed to register PMU devices!"); kfree(pmu); return ret; } static struct platform_driver cpu_pmu_driver = { .driver = { .name = "arm-pmu", .pm = &armpmu_dev_pm_ops, .of_match_table = cpu_pmu_of_device_ids, }, .probe = cpu_pmu_device_probe, .id_table = cpu_pmu_plat_device_ids, }; static int __init register_pmu_driver(void) { int err; err = register_cpu_notifier(&cpu_pmu_hotplug_notifier); if (err) return err; err = platform_driver_register(&cpu_pmu_driver); if (err) unregister_cpu_notifier(&cpu_pmu_hotplug_notifier); return err; } device_initcall(register_pmu_driver);