diff options
Diffstat (limited to 'arch/arm/kernel/perf_event_cpu.c')
-rw-r--r-- | arch/arm/kernel/perf_event_cpu.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c new file mode 100644 index 00000000000..66248ee706c --- /dev/null +++ b/arch/arm/kernel/perf_event_cpu.c @@ -0,0 +1,380 @@ +/* + * 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/cpu_pm.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 <asm/cputype.h> +#include <asm/irq_regs.h> +#include <asm/pmu.h> + +/* Set at runtime when we know what CPU type we are. */ +static DEFINE_PER_CPU(struct arm_pmu *, cpu_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); + +static DEFINE_PER_CPU(struct cpupmu_regs, cpu_pmu_regs); + +/* + * Despite the names, these two functions are CPU-specific and are used + * by the OProfile/perf code. + */ +const char *perf_pmu_name(void) +{ + struct arm_pmu *pmu = per_cpu(cpu_pmu, 0); + if (!pmu) + return NULL; + + return pmu->name; +} +EXPORT_SYMBOL_GPL(perf_pmu_name); + +int perf_num_counters(void) +{ + struct arm_pmu *pmu = per_cpu(cpu_pmu, 0); + + if (!pmu) + return 0; + + return pmu->num_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 &__get_cpu_var(cpu_hw_events); +} + +static void cpu_pmu_free_irq(struct arm_pmu *cpu_pmu) +{ + int i, irq, irqs; + struct platform_device *pmu_device = cpu_pmu->plat_device; + int cpu = -1; + + irqs = min(pmu_device->num_resources, num_possible_cpus()); + + for (i = 0; i < irqs; ++i) { + cpu = cpumask_next(cpu, &cpu_pmu->valid_cpus); + 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, 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; + int cpu = -1; + + if (!pmu_device) + return -ENODEV; + + irqs = min(pmu_device->num_resources, num_possible_cpus()); + if (irqs < 1) { + pr_err("no irqs for PMUs defined\n"); + return -ENODEV; + } + + for (i = 0; i < irqs; ++i) { + err = 0; + cpu = cpumask_next(cpu, &cpu_pmu->valid_cpus); + 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(cpu)) && irqs > 1) { + pr_warning("unable to set irq affinity (irq=%d, cpu=%u)\n", + irq, i); + continue; + } + + err = request_irq(irq, handler, IRQF_NOBALANCING, "arm-pmu", + cpu_pmu); + 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; +} + +static void __devinit cpu_pmu_init(struct arm_pmu *cpu_pmu) +{ + int cpu; + for_each_cpu_mask(cpu, cpu_pmu->valid_cpus) { + 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); + } + + 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 && cpu_pmu->reset) + on_each_cpu_mask(&cpu_pmu->valid_cpus, cpu_pmu->reset, cpu_pmu, 1); +} + +/* + * 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 __cpuinit cpu_pmu_notify(struct notifier_block *b, + unsigned long action, void *hcpu) +{ + struct arm_pmu *pmu = per_cpu(cpu_pmu, (long)hcpu); + + if ((action & ~CPU_TASKS_FROZEN) != CPU_STARTING) + return NOTIFY_DONE; + + if (pmu && pmu->reset) + pmu->reset(pmu); + else + return NOTIFY_DONE; + + return NOTIFY_OK; +} + +static int cpu_pmu_pm_notify(struct notifier_block *b, + unsigned long action, void *hcpu) +{ + int cpu = smp_processor_id(); + struct arm_pmu *pmu = per_cpu(cpu_pmu, cpu); + struct cpupmu_regs *pmuregs = &per_cpu(cpu_pmu_regs, cpu); + + if (!pmu) + return NOTIFY_DONE; + + if (action == CPU_PM_ENTER && pmu->save_regs) { + pmu->save_regs(pmu, pmuregs); + } else if (action == CPU_PM_EXIT && pmu->restore_regs) { + pmu->restore_regs(pmu, pmuregs); + } + + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata cpu_pmu_hotplug_notifier = { + .notifier_call = cpu_pmu_notify, +}; + +static struct notifier_block __cpuinitdata cpu_pmu_pm_notifier = { + .notifier_call = cpu_pmu_pm_notify, +}; + +/* + * PMU platform driver and devicetree bindings. + */ +static struct of_device_id __devinitdata cpu_pmu_of_device_ids[] = { + {.compatible = "arm,cortex-a15-pmu", .data = armv7_a15_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 = armv6pmu_init}, + {.compatible = "arm,arm1136-pmu", .data = armv6pmu_init}, + {}, +}; + +static struct platform_device_id __devinitdata cpu_pmu_plat_device_ids[] = { + {.name = "arm-pmu"}, + {}, +}; + +/* + * CPU PMU identification and probing. + */ +static int __devinit probe_current_pmu(struct arm_pmu *pmu) +{ + int cpu = get_cpu(); + unsigned long cpuid = read_cpuid_id(); + unsigned long implementor = (cpuid & 0xFF000000) >> 24; + unsigned long part_number = (cpuid & 0xFFF0); + int ret = -ENODEV; + + pr_info("probing PMU on CPU %d\n", cpu); + + /* ARM Ltd CPUs. */ + if (0x41 == implementor) { + switch (part_number) { + case 0xB360: /* ARM1136 */ + case 0xB560: /* ARM1156 */ + case 0xB760: /* ARM1176 */ + ret = armv6pmu_init(pmu); + break; + case 0xB020: /* ARM11mpcore */ + ret = armv6mpcore_pmu_init(pmu); + break; + case 0xC080: /* Cortex-A8 */ + ret = armv7_a8_pmu_init(pmu); + break; + case 0xC090: /* Cortex-A9 */ + ret = armv7_a9_pmu_init(pmu); + break; + case 0xC050: /* Cortex-A5 */ + ret = armv7_a5_pmu_init(pmu); + break; + case 0xC0F0: /* Cortex-A15 */ + ret = armv7_a15_pmu_init(pmu); + break; + case 0xC070: /* Cortex-A7 */ + ret = armv7_a7_pmu_init(pmu); + break; + } + /* Intel CPUs [xscale]. */ + } else if (0x69 == implementor) { + part_number = (cpuid >> 13) & 0x7; + switch (part_number) { + case 1: + ret = xscale1pmu_init(pmu); + break; + case 2: + ret = xscale2pmu_init(pmu); + break; + } + } + + /* assume PMU support all the CPUs in this case */ + cpumask_setall(&pmu->valid_cpus); + + put_cpu(); + return ret; +} + +static int __devinit cpu_pmu_device_probe(struct platform_device *pdev) +{ + const struct of_device_id *of_id; + struct device_node *node = pdev->dev.of_node; + struct arm_pmu *pmu; + int ret = 0; + int cpu; + + pmu = kzalloc(sizeof(struct arm_pmu), GFP_KERNEL); + if (!pmu) { + pr_info("failed to allocate PMU device!"); + return -ENOMEM; + } + + if (node && (of_id = of_match_node(cpu_pmu_of_device_ids, pdev->dev.of_node))) { + smp_call_func_t init_fn = (smp_call_func_t)of_id->data; + struct device_node *ncluster; + int cluster = -1; + cpumask_t sibling_mask; + + ncluster = of_parse_phandle(node, "cluster", 0); + if (ncluster) { + int len; + const u32 *hwid; + hwid = of_get_property(ncluster, "reg", &len); + if (hwid && len == 4) + cluster = be32_to_cpup(hwid); + } + /* set sibling mask to all cpu mask if socket is not specified */ + if (cluster == -1 || + cluster_to_logical_mask(cluster, &sibling_mask)) + cpumask_setall(&sibling_mask); + + smp_call_function_any(&sibling_mask, init_fn, pmu, 1); + + /* now set the valid_cpus after init */ + cpumask_copy(&pmu->valid_cpus, &sibling_mask); + } else { + ret = probe_current_pmu(pmu); + } + + if (ret) { + pr_info("failed to register PMU devices!"); + kfree(pmu); + return ret; + } + + for_each_cpu_mask(cpu, pmu->valid_cpus) + per_cpu(cpu_pmu, cpu) = pmu; + + pmu->plat_device = pdev; + cpu_pmu_init(pmu); + armpmu_register(pmu, -1); + + return 0; +} + +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 = cpu_pm_register_notifier(&cpu_pmu_pm_notifier); + if (err) { + unregister_cpu_notifier(&cpu_pmu_hotplug_notifier); + return err; + } + + err = platform_driver_register(&cpu_pmu_driver); + if (err) { + cpu_pm_unregister_notifier(&cpu_pmu_pm_notifier); + unregister_cpu_notifier(&cpu_pmu_hotplug_notifier); + } + + return err; +} +device_initcall(register_pmu_driver); |