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-rw-r--r--arch/arm/kernel/perf_event_cpu.c319
1 files changed, 319 insertions, 0 deletions
diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c
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--- /dev/null
+++ b/arch/arm/kernel/perf_event_cpu.c
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+/*
+ * 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 <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 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 &__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;
+
+ irqs = min(pmu_device->num_resources, num_possible_cpus());
+
+ 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) {
+ pr_err("no irqs for PMUs defined\n");
+ return -ENODEV;
+ }
+
+ 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_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(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);
+ }
+
+ 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(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)
+{
+ 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 __cpuinitdata 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-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 cpu_pmu_plat_device_ids[] = {
+ {.name = "arm-pmu"},
+ {},
+};
+
+/*
+ * CPU PMU identification and probing.
+ */
+static int 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;
+ }
+ }
+
+ put_cpu();
+ return ret;
+}
+
+static int cpu_pmu_device_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id;
+ 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;
+ }
+
+ 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 register PMU devices!");
+ kfree(pmu);
+ return ret;
+ }
+
+ cpu_pmu = pmu;
+ cpu_pmu->plat_device = pdev;
+ cpu_pmu_init(cpu_pmu);
+ armpmu_register(cpu_pmu, PERF_TYPE_RAW);
+
+ 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 = platform_driver_register(&cpu_pmu_driver);
+ if (err)
+ unregister_cpu_notifier(&cpu_pmu_hotplug_notifier);
+
+ return err;
+}
+device_initcall(register_pmu_driver);