[PATCH v2 25/31] arm64: Performance counters support
Catalin Marinas
catalin.marinas at arm.com
Tue Aug 14 13:52:26 EDT 2012
From: Will Deacon <will.deacon at arm.com>
This patch adds support for the AArch64 performance counters.
Signed-off-by: Will Deacon <will.deacon at arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas at arm.com>
---
arch/arm64/include/asm/perf_event.h | 22 +
arch/arm64/include/asm/pmu.h | 82 +++
arch/arm64/kernel/perf_event.c | 1368 +++++++++++++++++++++++++++++++++++
tools/perf/perf.h | 6 +
4 files changed, 1478 insertions(+), 0 deletions(-)
create mode 100644 arch/arm64/include/asm/perf_event.h
create mode 100644 arch/arm64/include/asm/pmu.h
create mode 100644 arch/arm64/kernel/perf_event.c
diff --git a/arch/arm64/include/asm/perf_event.h b/arch/arm64/include/asm/perf_event.h
new file mode 100644
index 0000000..a6fffd5
--- /dev/null
+++ b/arch/arm64/include/asm/perf_event.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ASM_PERF_EVENT_H
+#define __ASM_PERF_EVENT_H
+
+/* It's quiet around here... */
+
+#endif
diff --git a/arch/arm64/include/asm/pmu.h b/arch/arm64/include/asm/pmu.h
new file mode 100644
index 0000000..e6f0878
--- /dev/null
+++ b/arch/arm64/include/asm/pmu.h
@@ -0,0 +1,82 @@
+/*
+ * Based on arch/arm/include/asm/pmu.h
+ *
+ * Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
+ * Copyright (C) 2012 ARM Ltd.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef __ASM_PMU_H
+#define __ASM_PMU_H
+
+#ifdef CONFIG_HW_PERF_EVENTS
+
+/* The events for a given PMU register set. */
+struct pmu_hw_events {
+ /*
+ * The events that are active on the PMU for the given index.
+ */
+ struct perf_event **events;
+
+ /*
+ * A 1 bit for an index indicates that the counter is being used for
+ * an event. A 0 means that the counter can be used.
+ */
+ unsigned long *used_mask;
+
+ /*
+ * Hardware lock to serialize accesses to PMU registers. Needed for the
+ * read/modify/write sequences.
+ */
+ raw_spinlock_t pmu_lock;
+};
+
+struct arm_pmu {
+ struct pmu pmu;
+ cpumask_t active_irqs;
+ const char *name;
+ irqreturn_t (*handle_irq)(int irq_num, void *dev);
+ void (*enable)(struct hw_perf_event *evt, int idx);
+ void (*disable)(struct hw_perf_event *evt, int idx);
+ int (*get_event_idx)(struct pmu_hw_events *hw_events,
+ struct hw_perf_event *hwc);
+ int (*set_event_filter)(struct hw_perf_event *evt,
+ struct perf_event_attr *attr);
+ u32 (*read_counter)(int idx);
+ void (*write_counter)(int idx, u32 val);
+ void (*start)(void);
+ void (*stop)(void);
+ void (*reset)(void *);
+ int (*map_event)(struct perf_event *event);
+ int num_events;
+ atomic_t active_events;
+ struct mutex reserve_mutex;
+ u64 max_period;
+ struct platform_device *plat_device;
+ struct pmu_hw_events *(*get_hw_events)(void);
+};
+
+#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
+
+int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type);
+
+u64 armpmu_event_update(struct perf_event *event,
+ struct hw_perf_event *hwc,
+ int idx);
+
+int armpmu_event_set_period(struct perf_event *event,
+ struct hw_perf_event *hwc,
+ int idx);
+
+#endif /* CONFIG_HW_PERF_EVENTS */
+#endif /* __ASM_PMU_H */
diff --git a/arch/arm64/kernel/perf_event.c b/arch/arm64/kernel/perf_event.c
new file mode 100644
index 0000000..ecbf2d8
--- /dev/null
+++ b/arch/arm64/kernel/perf_event.c
@@ -0,0 +1,1368 @@
+/*
+ * PMU support
+ *
+ * Copyright (C) 2012 ARM Limited
+ * Author: Will Deacon <will.deacon at arm.com>
+ *
+ * This code is based heavily on the ARMv7 perf event code.
+ *
+ * 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, see <http://www.gnu.org/licenses/>.
+ */
+#define pr_fmt(fmt) "hw perfevents: " fmt
+
+#include <linux/bitmap.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/export.h>
+#include <linux/perf_event.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/uaccess.h>
+
+#include <asm/cputype.h>
+#include <asm/irq.h>
+#include <asm/irq_regs.h>
+#include <asm/pmu.h>
+#include <asm/stacktrace.h>
+
+/*
+ * ARMv8 supports a maximum of 32 events.
+ * The cycle counter is included in this total.
+ */
+#define ARMPMU_MAX_HWEVENTS 32
+
+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);
+
+#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
+
+/* Set at runtime when we know what CPU type we are. */
+static struct arm_pmu *cpu_pmu;
+
+int
+armpmu_get_max_events(void)
+{
+ int max_events = 0;
+
+ if (cpu_pmu != NULL)
+ max_events = cpu_pmu->num_events;
+
+ return max_events;
+}
+EXPORT_SYMBOL_GPL(armpmu_get_max_events);
+
+int perf_num_counters(void)
+{
+ return armpmu_get_max_events();
+}
+EXPORT_SYMBOL_GPL(perf_num_counters);
+
+#define HW_OP_UNSUPPORTED 0xFFFF
+
+#define C(_x) \
+ PERF_COUNT_HW_CACHE_##_x
+
+#define CACHE_OP_UNSUPPORTED 0xFFFF
+
+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_event(const unsigned (*event_map)[PERF_COUNT_HW_MAX], u64 config)
+{
+ int 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);
+}
+
+static int map_cpu_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;
+
+ switch (event->attr.type) {
+ case PERF_TYPE_HARDWARE:
+ return armpmu_map_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 hw_perf_event *hwc,
+ int idx)
+{
+ struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
+ 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;
+ }
+
+ if (left > (s64)armpmu->max_period)
+ left = armpmu->max_period;
+
+ local64_set(&hwc->prev_count, (u64)-left);
+
+ armpmu->write_counter(idx, (u64)(-left) & 0xffffffff);
+
+ perf_event_update_userpage(event);
+
+ return ret;
+}
+
+u64
+armpmu_event_update(struct perf_event *event,
+ struct hw_perf_event *hwc,
+ int idx)
+{
+ struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
+ u64 delta, prev_raw_count, new_raw_count;
+
+again:
+ prev_raw_count = local64_read(&hwc->prev_count);
+ new_raw_count = armpmu->read_counter(idx);
+
+ 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)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ /* Don't read disabled counters! */
+ if (hwc->idx < 0)
+ return;
+
+ armpmu_event_update(event, hwc, hwc->idx);
+}
+
+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(hwc, hwc->idx);
+ barrier(); /* why? */
+ armpmu_event_update(event, hwc, hwc->idx);
+ 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, hwc, hwc->idx);
+ armpmu->enable(hwc, hwc->idx);
+}
+
+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 = armpmu->get_hw_events();
+ struct hw_perf_event *hwc = &event->hw;
+ int idx = hwc->idx;
+
+ WARN_ON(idx < 0);
+
+ armpmu_stop(event, PERF_EF_UPDATE);
+ hw_events->events[idx] = NULL;
+ clear_bit(idx, hw_events->used_mask);
+
+ 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 = armpmu->get_hw_events();
+ struct hw_perf_event *hwc = &event->hw;
+ int idx;
+ int err = 0;
+
+ 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, hwc);
+ 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(hwc, idx);
+ 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_hw_events *hw_events,
+ struct perf_event *event)
+{
+ struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
+ struct hw_perf_event fake_event = event->hw;
+ struct pmu *leader_pmu = event->group_leader->pmu;
+
+ if (event->pmu != leader_pmu || event->state <= PERF_EVENT_STATE_OFF)
+ return 1;
+
+ return armpmu->get_event_idx(hw_events, &fake_event) >= 0;
+}
+
+static int
+validate_group(struct perf_event *event)
+{
+ struct perf_event *sibling, *leader = event->group_leader;
+ struct pmu_hw_events fake_pmu;
+ DECLARE_BITMAP(fake_used_mask, ARMPMU_MAX_HWEVENTS);
+
+ /*
+ * Initialise the fake PMU. We only need to populate the
+ * used_mask for the purposes of validation.
+ */
+ memset(fake_used_mask, 0, sizeof(fake_used_mask));
+ fake_pmu.used_mask = fake_used_mask;
+
+ if (!validate_event(&fake_pmu, leader))
+ return -EINVAL;
+
+ list_for_each_entry(sibling, &leader->sibling_list, group_entry) {
+ if (!validate_event(&fake_pmu, sibling))
+ return -EINVAL;
+ }
+
+ if (!validate_event(&fake_pmu, event))
+ return -EINVAL;
+
+ return 0;
+}
+
+static void
+armpmu_release_hardware(struct arm_pmu *armpmu)
+{
+ int i, irq, irqs;
+ struct platform_device *pmu_device = armpmu->plat_device;
+
+ irqs = min(pmu_device->num_resources, num_possible_cpus());
+
+ for (i = 0; i < irqs; ++i) {
+ if (!cpumask_test_and_clear_cpu(i, &armpmu->active_irqs))
+ continue;
+ irq = platform_get_irq(pmu_device, i);
+ if (irq >= 0)
+ free_irq(irq, armpmu);
+ }
+}
+
+static int
+armpmu_reserve_hardware(struct arm_pmu *armpmu)
+{
+ int i, err, irq, irqs;
+ struct platform_device *pmu_device = armpmu->plat_device;
+
+ if (!pmu_device) {
+ pr_err("no PMU device registered\n");
+ 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, armpmu->handle_irq,
+ IRQF_NOBALANCING,
+ "arm-pmu", armpmu);
+ if (err) {
+ pr_err("unable to request IRQ%d for ARM PMU counters\n",
+ irq);
+ armpmu_release_hardware(armpmu);
+ return err;
+ }
+
+ cpumask_set_cpu(i, &armpmu->active_irqs);
+ }
+
+ 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, err;
+
+ 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 -EPERM;
+ }
+
+ /*
+ * Store the event encoding into the config_base field.
+ */
+ hwc->config_base |= (unsigned long)mapping;
+
+ if (!hwc->sample_period) {
+ /*
+ * 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);
+ }
+
+ err = 0;
+ if (event->group_leader != event) {
+ err = validate_group(event);
+ if (err)
+ return -EINVAL;
+ }
+
+ return err;
+}
+
+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;
+
+ 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 = armpmu->get_hw_events();
+ int enabled = bitmap_weight(hw_events->used_mask, armpmu->num_events);
+
+ if (enabled)
+ armpmu->start();
+}
+
+static void armpmu_disable(struct pmu *pmu)
+{
+ struct arm_pmu *armpmu = to_arm_pmu(pmu);
+ armpmu->stop();
+}
+
+static void __init 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,
+ };
+}
+
+int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type)
+{
+ armpmu_init(armpmu);
+ return perf_pmu_register(&armpmu->pmu, name, type);
+}
+
+/*
+ * ARMv8 PMUv3 Performance Events handling code.
+ * Common event types.
+ */
+enum armv8_pmuv3_perf_types {
+ /* Required events. */
+ ARMV8_PMUV3_PERFCTR_PMNC_SW_INCR = 0x00,
+ ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL = 0x03,
+ ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS = 0x04,
+ ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED = 0x10,
+ ARMV8_PMUV3_PERFCTR_CLOCK_CYCLES = 0x11,
+ ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED = 0x12,
+
+ /* At least one of the following is required. */
+ ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED = 0x08,
+ ARMV8_PMUV3_PERFCTR_OP_SPEC = 0x1B,
+
+ /* Common architectural events. */
+ ARMV8_PMUV3_PERFCTR_MEM_READ = 0x06,
+ ARMV8_PMUV3_PERFCTR_MEM_WRITE = 0x07,
+ ARMV8_PMUV3_PERFCTR_EXC_TAKEN = 0x09,
+ ARMV8_PMUV3_PERFCTR_EXC_EXECUTED = 0x0A,
+ ARMV8_PMUV3_PERFCTR_CID_WRITE = 0x0B,
+ ARMV8_PMUV3_PERFCTR_PC_WRITE = 0x0C,
+ ARMV8_PMUV3_PERFCTR_PC_IMM_BRANCH = 0x0D,
+ ARMV8_PMUV3_PERFCTR_PC_PROC_RETURN = 0x0E,
+ ARMV8_PMUV3_PERFCTR_MEM_UNALIGNED_ACCESS = 0x0F,
+ ARMV8_PMUV3_PERFCTR_TTBR_WRITE = 0x1C,
+
+ /* Common microarchitectural events. */
+ ARMV8_PMUV3_PERFCTR_L1_ICACHE_REFILL = 0x01,
+ ARMV8_PMUV3_PERFCTR_ITLB_REFILL = 0x02,
+ ARMV8_PMUV3_PERFCTR_DTLB_REFILL = 0x05,
+ ARMV8_PMUV3_PERFCTR_MEM_ACCESS = 0x13,
+ ARMV8_PMUV3_PERFCTR_L1_ICACHE_ACCESS = 0x14,
+ ARMV8_PMUV3_PERFCTR_L1_DCACHE_WB = 0x15,
+ ARMV8_PMUV3_PERFCTR_L2_CACHE_ACCESS = 0x16,
+ ARMV8_PMUV3_PERFCTR_L2_CACHE_REFILL = 0x17,
+ ARMV8_PMUV3_PERFCTR_L2_CACHE_WB = 0x18,
+ ARMV8_PMUV3_PERFCTR_BUS_ACCESS = 0x19,
+ ARMV8_PMUV3_PERFCTR_MEM_ERROR = 0x1A,
+ ARMV8_PMUV3_PERFCTR_BUS_CYCLES = 0x1D,
+
+ /*
+ * This isn't an architected event.
+ * We detect this event number and use the cycle counter instead.
+ */
+ ARMV8_PMUV3_PERFCTR_CPU_CYCLES = 0xFF,
+};
+
+/* PMUv3 HW events mapping. */
+static const unsigned armv8_pmuv3_perf_map[PERF_COUNT_HW_MAX] = {
+ [PERF_COUNT_HW_CPU_CYCLES] = ARMV8_PMUV3_PERFCTR_CPU_CYCLES,
+ [PERF_COUNT_HW_INSTRUCTIONS] = ARMV8_PMUV3_PERFCTR_INSTR_EXECUTED,
+ [PERF_COUNT_HW_CACHE_REFERENCES] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
+ [PERF_COUNT_HW_CACHE_MISSES] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
+ [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = HW_OP_UNSUPPORTED,
+ [PERF_COUNT_HW_BRANCH_MISSES] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
+ [PERF_COUNT_HW_BUS_CYCLES] = HW_OP_UNSUPPORTED,
+ [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND] = HW_OP_UNSUPPORTED,
+ [PERF_COUNT_HW_STALLED_CYCLES_BACKEND] = HW_OP_UNSUPPORTED,
+};
+
+static const unsigned armv8_pmuv3_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
+ [PERF_COUNT_HW_CACHE_OP_MAX]
+ [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
+ [C(L1D)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
+ [C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_ACCESS,
+ [C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_L1_DCACHE_REFILL,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(L1I)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(LL)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(DTLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(ITLB)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(BPU)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
+ [C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_PRED,
+ [C(RESULT_MISS)] = ARMV8_PMUV3_PERFCTR_PC_BRANCH_MIS_PRED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+ [C(NODE)] = {
+ [C(OP_READ)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_WRITE)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ [C(OP_PREFETCH)] = {
+ [C(RESULT_ACCESS)] = CACHE_OP_UNSUPPORTED,
+ [C(RESULT_MISS)] = CACHE_OP_UNSUPPORTED,
+ },
+ },
+};
+
+/*
+ * Perf Events' indices
+ */
+#define ARMV8_IDX_CYCLE_COUNTER 0
+#define ARMV8_IDX_COUNTER0 1
+#define ARMV8_IDX_COUNTER_LAST (ARMV8_IDX_CYCLE_COUNTER + cpu_pmu->num_events - 1)
+
+#define ARMV8_MAX_COUNTERS 32
+#define ARMV8_COUNTER_MASK (ARMV8_MAX_COUNTERS - 1)
+
+/*
+ * ARMv8 low level PMU access
+ */
+
+/*
+ * Perf Event to low level counters mapping
+ */
+#define ARMV8_IDX_TO_COUNTER(x) \
+ (((x) - ARMV8_IDX_COUNTER0) & ARMV8_COUNTER_MASK)
+
+/*
+ * Per-CPU PMCR: config reg
+ */
+#define ARMV8_PMCR_E (1 << 0) /* Enable all counters */
+#define ARMV8_PMCR_P (1 << 1) /* Reset all counters */
+#define ARMV8_PMCR_C (1 << 2) /* Cycle counter reset */
+#define ARMV8_PMCR_D (1 << 3) /* CCNT counts every 64th cpu cycle */
+#define ARMV8_PMCR_X (1 << 4) /* Export to ETM */
+#define ARMV8_PMCR_DP (1 << 5) /* Disable CCNT if non-invasive debug*/
+#define ARMV8_PMCR_N_SHIFT 11 /* Number of counters supported */
+#define ARMV8_PMCR_N_MASK 0x1f
+#define ARMV8_PMCR_MASK 0x3f /* Mask for writable bits */
+
+/*
+ * PMOVSR: counters overflow flag status reg
+ */
+#define ARMV8_OVSR_MASK 0xffffffff /* Mask for writable bits */
+#define ARMV8_OVERFLOWED_MASK ARMV8_OVSR_MASK
+
+/*
+ * PMXEVTYPER: Event selection reg
+ */
+#define ARMV8_EVTYPE_MASK 0xc00000ff /* Mask for writable bits */
+#define ARMV8_EVTYPE_EVENT 0xff /* Mask for EVENT bits */
+
+/*
+ * Event filters for PMUv3
+ */
+#define ARMV8_EXCLUDE_EL1 (1 << 31)
+#define ARMV8_EXCLUDE_EL0 (1 << 30)
+#define ARMV8_INCLUDE_EL2 (1 << 27)
+
+static inline u32 armv8pmu_pmcr_read(void)
+{
+ u32 val;
+ asm volatile("mrs %0, pmcr_el0" : "=r" (val));
+ return val;
+}
+
+static inline void armv8pmu_pmcr_write(u32 val)
+{
+ val &= ARMV8_PMCR_MASK;
+ isb();
+ asm volatile("msr pmcr_el0, %0" :: "r" (val));
+}
+
+static inline int armv8pmu_has_overflowed(u32 pmovsr)
+{
+ return pmovsr & ARMV8_OVERFLOWED_MASK;
+}
+
+static inline int armv8pmu_counter_valid(int idx)
+{
+ return idx >= ARMV8_IDX_CYCLE_COUNTER && idx <= ARMV8_IDX_COUNTER_LAST;
+}
+
+static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
+{
+ int ret = 0;
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u checking wrong counter %d overflow status\n",
+ smp_processor_id(), idx);
+ } else {
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ ret = pmnc & BIT(counter);
+ }
+
+ return ret;
+}
+
+static inline int armv8pmu_select_counter(int idx)
+{
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u selecting wrong PMNC counter %d\n",
+ smp_processor_id(), idx);
+ return -EINVAL;
+ }
+
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ asm volatile("msr pmselr_el0, %0" :: "r" (counter));
+ isb();
+
+ return idx;
+}
+
+static inline u32 armv8pmu_read_counter(int idx)
+{
+ u32 value = 0;
+
+ if (!armv8pmu_counter_valid(idx))
+ pr_err("CPU%u reading wrong counter %d\n",
+ smp_processor_id(), idx);
+ else if (idx == ARMV8_IDX_CYCLE_COUNTER)
+ asm volatile("mrs %0, pmccntr_el0" : "=r" (value));
+ else if (armv8pmu_select_counter(idx) == idx)
+ asm volatile("mrs %0, pmxevcntr_el0" : "=r" (value));
+
+ return value;
+}
+
+static inline void armv8pmu_write_counter(int idx, u32 value)
+{
+ if (!armv8pmu_counter_valid(idx))
+ pr_err("CPU%u writing wrong counter %d\n",
+ smp_processor_id(), idx);
+ else if (idx == ARMV8_IDX_CYCLE_COUNTER)
+ asm volatile("msr pmccntr_el0, %0" :: "r" (value));
+ else if (armv8pmu_select_counter(idx) == idx)
+ asm volatile("msr pmxevcntr_el0, %0" :: "r" (value));
+}
+
+static inline void armv8pmu_write_evtype(int idx, u32 val)
+{
+ if (armv8pmu_select_counter(idx) == idx) {
+ val &= ARMV8_EVTYPE_MASK;
+ asm volatile("msr pmxevtyper_el0, %0" :: "r" (val));
+ }
+}
+
+static inline int armv8pmu_enable_counter(int idx)
+{
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u enabling wrong PMNC counter %d\n",
+ smp_processor_id(), idx);
+ return -EINVAL;
+ }
+
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ asm volatile("msr pmcntenset_el0, %0" :: "r" (BIT(counter)));
+ return idx;
+}
+
+static inline int armv8pmu_disable_counter(int idx)
+{
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u disabling wrong PMNC counter %d\n",
+ smp_processor_id(), idx);
+ return -EINVAL;
+ }
+
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ asm volatile("msr pmcntenclr_el0, %0" :: "r" (BIT(counter)));
+ return idx;
+}
+
+static inline int armv8pmu_enable_intens(int idx)
+{
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u enabling wrong PMNC counter IRQ enable %d\n",
+ smp_processor_id(), idx);
+ return -EINVAL;
+ }
+
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ asm volatile("msr pmintenset_el1, %0" :: "r" (BIT(counter)));
+ return idx;
+}
+
+static inline int armv8pmu_disable_intens(int idx)
+{
+ u32 counter;
+
+ if (!armv8pmu_counter_valid(idx)) {
+ pr_err("CPU%u disabling wrong PMNC counter IRQ enable %d\n",
+ smp_processor_id(), idx);
+ return -EINVAL;
+ }
+
+ counter = ARMV8_IDX_TO_COUNTER(idx);
+ asm volatile("msr pmintenclr_el1, %0" :: "r" (BIT(counter)));
+ isb();
+ /* Clear the overflow flag in case an interrupt is pending. */
+ asm volatile("msr pmovsclr_el0, %0" :: "r" (BIT(counter)));
+ isb();
+ return idx;
+}
+
+static inline u32 armv8pmu_getreset_flags(void)
+{
+ u32 value;
+
+ /* Read */
+ asm volatile("mrs %0, pmovsclr_el0" : "=r" (value));
+
+ /* Write to clear flags */
+ value &= ARMV8_OVSR_MASK;
+ asm volatile("msr pmovsclr_el0, %0" :: "r" (value));
+
+ return value;
+}
+
+static void armv8pmu_enable_event(struct hw_perf_event *hwc, int idx)
+{
+ unsigned long flags;
+ struct pmu_hw_events *events = cpu_pmu->get_hw_events();
+
+ /*
+ * Enable counter and interrupt, and set the counter to count
+ * the event that we're interested in.
+ */
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+
+ /*
+ * Disable counter
+ */
+ armv8pmu_disable_counter(idx);
+
+ /*
+ * Set event (if destined for PMNx counters).
+ */
+ armv8pmu_write_evtype(idx, hwc->config_base);
+
+ /*
+ * Enable interrupt for this counter
+ */
+ armv8pmu_enable_intens(idx);
+
+ /*
+ * Enable counter
+ */
+ armv8pmu_enable_counter(idx);
+
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static void armv8pmu_disable_event(struct hw_perf_event *hwc, int idx)
+{
+ unsigned long flags;
+ struct pmu_hw_events *events = cpu_pmu->get_hw_events();
+
+ /*
+ * Disable counter and interrupt
+ */
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+
+ /*
+ * Disable counter
+ */
+ armv8pmu_disable_counter(idx);
+
+ /*
+ * Disable interrupt for this counter
+ */
+ armv8pmu_disable_intens(idx);
+
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static irqreturn_t armv8pmu_handle_irq(int irq_num, void *dev)
+{
+ u32 pmovsr;
+ struct perf_sample_data data;
+ struct pmu_hw_events *cpuc;
+ struct pt_regs *regs;
+ int idx;
+
+ /*
+ * Get and reset the IRQ flags
+ */
+ pmovsr = armv8pmu_getreset_flags();
+
+ /*
+ * Did an overflow occur?
+ */
+ if (!armv8pmu_has_overflowed(pmovsr))
+ return IRQ_NONE;
+
+ /*
+ * Handle the counter(s) overflow(s)
+ */
+ regs = get_irq_regs();
+
+ cpuc = &__get_cpu_var(cpu_hw_events);
+ for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
+ struct perf_event *event = cpuc->events[idx];
+ struct hw_perf_event *hwc;
+
+ /* Ignore if we don't have an event. */
+ if (!event)
+ continue;
+
+ /*
+ * We have a single interrupt for all counters. Check that
+ * each counter has overflowed before we process it.
+ */
+ if (!armv8pmu_counter_has_overflowed(pmovsr, idx))
+ continue;
+
+ hwc = &event->hw;
+ armpmu_event_update(event, hwc, idx);
+ perf_sample_data_init(&data, 0, hwc->last_period);
+ if (!armpmu_event_set_period(event, hwc, idx))
+ continue;
+
+ if (perf_event_overflow(event, &data, regs))
+ cpu_pmu->disable(hwc, idx);
+ }
+
+ /*
+ * Handle the pending perf events.
+ *
+ * Note: this call *must* be run with interrupts disabled. For
+ * platforms that can have the PMU interrupts raised as an NMI, this
+ * will not work.
+ */
+ irq_work_run();
+
+ return IRQ_HANDLED;
+}
+
+static void armv8pmu_start(void)
+{
+ unsigned long flags;
+ struct pmu_hw_events *events = cpu_pmu->get_hw_events();
+
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ /* Enable all counters */
+ armv8pmu_pmcr_write(armv8pmu_pmcr_read() | ARMV8_PMCR_E);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static void armv8pmu_stop(void)
+{
+ unsigned long flags;
+ struct pmu_hw_events *events = cpu_pmu->get_hw_events();
+
+ raw_spin_lock_irqsave(&events->pmu_lock, flags);
+ /* Disable all counters */
+ armv8pmu_pmcr_write(armv8pmu_pmcr_read() & ~ARMV8_PMCR_E);
+ raw_spin_unlock_irqrestore(&events->pmu_lock, flags);
+}
+
+static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc,
+ struct hw_perf_event *event)
+{
+ int idx;
+ unsigned long evtype = event->config_base & ARMV8_EVTYPE_EVENT;
+
+ /* Always place a cycle counter into the cycle counter. */
+ if (evtype == ARMV8_PMUV3_PERFCTR_CPU_CYCLES) {
+ if (test_and_set_bit(ARMV8_IDX_CYCLE_COUNTER, cpuc->used_mask))
+ return -EAGAIN;
+
+ return ARMV8_IDX_CYCLE_COUNTER;
+ }
+
+ /*
+ * For anything other than a cycle counter, try and use
+ * the events counters
+ */
+ for (idx = ARMV8_IDX_COUNTER0; idx < cpu_pmu->num_events; ++idx) {
+ if (!test_and_set_bit(idx, cpuc->used_mask))
+ return idx;
+ }
+
+ /* The counters are all in use. */
+ return -EAGAIN;
+}
+
+/*
+ * Add an event filter to a given event. This will only work for PMUv2 PMUs.
+ */
+static int armv8pmu_set_event_filter(struct hw_perf_event *event,
+ struct perf_event_attr *attr)
+{
+ unsigned long config_base = 0;
+
+ if (attr->exclude_idle)
+ return -EPERM;
+ if (attr->exclude_user)
+ config_base |= ARMV8_EXCLUDE_EL0;
+ if (attr->exclude_kernel)
+ config_base |= ARMV8_EXCLUDE_EL1;
+ if (!attr->exclude_hv)
+ config_base |= ARMV8_INCLUDE_EL2;
+
+ /*
+ * Install the filter into config_base as this is used to
+ * construct the event type.
+ */
+ event->config_base = config_base;
+
+ return 0;
+}
+
+static void armv8pmu_reset(void *info)
+{
+ u32 idx, nb_cnt = cpu_pmu->num_events;
+
+ /* The counter and interrupt enable registers are unknown at reset. */
+ for (idx = ARMV8_IDX_CYCLE_COUNTER; idx < nb_cnt; ++idx)
+ armv8pmu_disable_event(NULL, idx);
+
+ /* Initialize & Reset PMNC: C and P bits. */
+ armv8pmu_pmcr_write(ARMV8_PMCR_P | ARMV8_PMCR_C);
+
+ /* Disable access from userspace. */
+ asm volatile("msr pmuserenr_el0, %0" :: "r" (0));
+}
+
+static int armv8_pmuv3_map_event(struct perf_event *event)
+{
+ return map_cpu_event(event, &armv8_pmuv3_perf_map,
+ &armv8_pmuv3_perf_cache_map, 0xFF);
+}
+
+static struct arm_pmu armv8pmu = {
+ .handle_irq = armv8pmu_handle_irq,
+ .enable = armv8pmu_enable_event,
+ .disable = armv8pmu_disable_event,
+ .read_counter = armv8pmu_read_counter,
+ .write_counter = armv8pmu_write_counter,
+ .get_event_idx = armv8pmu_get_event_idx,
+ .start = armv8pmu_start,
+ .stop = armv8pmu_stop,
+ .reset = armv8pmu_reset,
+ .max_period = (1LLU << 32) - 1,
+};
+
+static u32 __init armv8pmu_read_num_pmnc_events(void)
+{
+ u32 nb_cnt;
+
+ /* Read the nb of CNTx counters supported from PMNC */
+ nb_cnt = (armv8pmu_pmcr_read() >> ARMV8_PMCR_N_SHIFT) & ARMV8_PMCR_N_MASK;
+
+ /* Add the CPU cycles counter and return */
+ return nb_cnt + 1;
+}
+
+static struct arm_pmu *__init armv8_pmuv3_pmu_init(void)
+{
+ armv8pmu.name = "arm/armv8-pmuv3";
+ armv8pmu.map_event = armv8_pmuv3_map_event;
+ armv8pmu.num_events = armv8pmu_read_num_pmnc_events();
+ armv8pmu.set_event_filter = armv8pmu_set_event_filter;
+ return &armv8pmu;
+}
+
+/*
+ * Ensure the PMU has sane values out of reset.
+ * This requires SMP to be available, so exists as a separate initcall.
+ */
+static int __init
+cpu_pmu_reset(void)
+{
+ if (cpu_pmu && cpu_pmu->reset)
+ return on_each_cpu(cpu_pmu->reset, NULL, 1);
+ return 0;
+}
+arch_initcall(cpu_pmu_reset);
+
+/*
+ * PMU platform driver and devicetree bindings.
+ */
+static struct of_device_id armpmu_of_device_ids[] = {
+ {.compatible = "arm,armv8-pmuv3"},
+ {},
+};
+
+static int __devinit armpmu_device_probe(struct platform_device *pdev)
+{
+ if (!cpu_pmu)
+ return -ENODEV;
+
+ cpu_pmu->plat_device = pdev;
+ return 0;
+}
+
+static struct platform_driver armpmu_driver = {
+ .driver = {
+ .name = "arm-pmu",
+ .of_match_table = armpmu_of_device_ids,
+ },
+ .probe = armpmu_device_probe,
+};
+
+static int __init register_pmu_driver(void)
+{
+ return platform_driver_register(&armpmu_driver);
+}
+device_initcall(register_pmu_driver);
+
+static struct pmu_hw_events *armpmu_get_cpu_events(void)
+{
+ return &__get_cpu_var(cpu_hw_events);
+}
+
+static void __init cpu_pmu_init(struct arm_pmu *armpmu)
+{
+ 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);
+ }
+ armpmu->get_hw_events = armpmu_get_cpu_events;
+}
+
+static int __init init_hw_perf_events(void)
+{
+ u64 dfr = read_cpuid(ID_AA64DFR0_EL1);
+
+ switch ((dfr >> 8) & 0xf) {
+ case 0x1: /* PMUv3 */
+ cpu_pmu = armv8_pmuv3_pmu_init();
+ break;
+ }
+
+ if (cpu_pmu) {
+ pr_info("enabled with %s PMU driver, %d counters available\n",
+ cpu_pmu->name, cpu_pmu->num_events);
+ cpu_pmu_init(cpu_pmu);
+ armpmu_register(cpu_pmu, "cpu", PERF_TYPE_RAW);
+ } else {
+ pr_info("no hardware support available\n");
+ }
+
+ return 0;
+}
+early_initcall(init_hw_perf_events);
+
+/*
+ * Callchain handling code.
+ */
+struct frame_tail {
+ struct frame_tail __user *fp;
+ unsigned long lr;
+} __attribute__((packed));
+
+/*
+ * Get the return address for a single stackframe and return a pointer to the
+ * next frame tail.
+ */
+static struct frame_tail __user *
+user_backtrace(struct frame_tail __user *tail,
+ struct perf_callchain_entry *entry)
+{
+ struct frame_tail buftail;
+ unsigned long err;
+
+ /* Also check accessibility of one struct frame_tail beyond */
+ if (!access_ok(VERIFY_READ, tail, sizeof(buftail)))
+ return NULL;
+
+ pagefault_disable();
+ err = __copy_from_user_inatomic(&buftail, tail, sizeof(buftail));
+ pagefault_enable();
+
+ if (err)
+ return NULL;
+
+ perf_callchain_store(entry, buftail.lr);
+
+ /*
+ * Frame pointers should strictly progress back up the stack
+ * (towards higher addresses).
+ */
+ if (tail >= buftail.fp)
+ return NULL;
+
+ return buftail.fp;
+}
+
+void perf_callchain_user(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+ struct frame_tail __user *tail;
+
+ tail = (struct frame_tail __user *)regs->regs[29];
+
+ while (entry->nr < PERF_MAX_STACK_DEPTH &&
+ tail && !((unsigned long)tail & 0xf))
+ tail = user_backtrace(tail, entry);
+}
+
+/*
+ * Gets called by walk_stackframe() for every stackframe. This will be called
+ * whist unwinding the stackframe and is like a subroutine return so we use
+ * the PC.
+ */
+static int callchain_trace(struct stackframe *frame, void *data)
+{
+ struct perf_callchain_entry *entry = data;
+ perf_callchain_store(entry, frame->pc);
+ return 0;
+}
+
+void perf_callchain_kernel(struct perf_callchain_entry *entry,
+ struct pt_regs *regs)
+{
+ struct stackframe frame;
+
+ frame.fp = regs->regs[29];
+ frame.sp = regs->sp;
+ frame.pc = regs->pc;
+ walk_stackframe(&frame, callchain_trace, entry);
+}
diff --git a/tools/perf/perf.h b/tools/perf/perf.h
index f960ccb..8c36763 100644
--- a/tools/perf/perf.h
+++ b/tools/perf/perf.h
@@ -88,6 +88,12 @@ void get_term_dimensions(struct winsize *ws);
#define CPUINFO_PROC "Processor"
#endif
+#ifdef __aarch64__
+#include "../../arch/arm64/include/asm/unistd.h"
+#define rmb() asm volatile("dmb ld" ::: "memory")
+#define cpu_relax() asm volatile("yield" ::: "memory")
+#endif
+
#ifdef __mips__
#include "../../arch/mips/include/asm/unistd.h"
#define rmb() asm volatile( \
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