arm: perf: factor arm_pmu core out to drivers
authorMark Rutland <mark.rutland@arm.com>
Mon, 6 Jul 2015 11:23:53 +0000 (12:23 +0100)
committerWill Deacon <will.deacon@arm.com>
Fri, 31 Jul 2015 14:01:14 +0000 (15:01 +0100)
To enable sharing of the arm_pmu code with arm64, this patch factors it
out to drivers/perf/. A new drivers/perf directory is added for
performance monitor drivers to live under.

MAINTAINERS is updated accordingly. Files added previously without a
corresponsing MAINTAINERS update (perf_regs.c, perf_callchain.c, and
perf_event.h) are also added.

Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
[will: augmented Kconfig help slightly]
Signed-off-by: Will Deacon <will.deacon@arm.com>
15 files changed:
MAINTAINERS
arch/arm/Kconfig
arch/arm/include/asm/pmu.h [deleted file]
arch/arm/kernel/Makefile
arch/arm/kernel/perf_event.c [deleted file]
arch/arm/kernel/perf_event_v6.c
arch/arm/kernel/perf_event_v7.c
arch/arm/kernel/perf_event_xscale.c
arch/arm/mach-ux500/cpu-db8500.c
drivers/Kconfig
drivers/Makefile
drivers/perf/Kconfig [new file with mode: 0644]
drivers/perf/Makefile [new file with mode: 0644]
drivers/perf/arm_pmu.c [new file with mode: 0644]
include/linux/perf/arm_pmu.h [new file with mode: 0644]

index fd60784..485c92c 100644 (file)
@@ -799,11 +799,13 @@ F:        arch/arm/include/asm/floppy.h
 ARM PMU PROFILING AND DEBUGGING
 M:     Will Deacon <will.deacon@arm.com>
 S:     Maintained
-F:     arch/arm/kernel/perf_event*
+F:     arch/arm/kernel/perf_*
 F:     arch/arm/oprofile/common.c
-F:     arch/arm/include/asm/pmu.h
 F:     arch/arm/kernel/hw_breakpoint.c
 F:     arch/arm/include/asm/hw_breakpoint.h
+F:     arch/arm/include/asm/perf_event.h
+F:     drivers/perf/arm_pmu.c
+F:     include/linux/perf/arm_pmu.h
 
 ARM PORT
 M:     Russell King <linux@arm.linux.org.uk>
index 1c50210..4f7bc3d 100644 (file)
@@ -1701,12 +1701,8 @@ config HIGHPTE
          user-space 2nd level page tables to reside in high memory.
 
 config HW_PERF_EVENTS
-       bool "Enable hardware performance counter support for perf events"
-       depends on PERF_EVENTS
-       default y
-       help
-         Enable hardware performance counter support for perf events. If
-         disabled, perf events will use software events only.
+       def_bool y
+       depends on ARM_PMU
 
 config SYS_SUPPORTS_HUGETLBFS
        def_bool y
diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
deleted file mode 100644 (file)
index 3fc87df..0000000
+++ /dev/null
@@ -1,154 +0,0 @@
-/*
- *  linux/arch/arm/include/asm/pmu.h
- *
- *  Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
- *
- * 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.
- *
- */
-
-#ifndef __ARM_PMU_H__
-#define __ARM_PMU_H__
-
-#include <linux/interrupt.h>
-#include <linux/perf_event.h>
-
-#include <asm/cputype.h>
-
-/*
- * struct arm_pmu_platdata - ARM PMU platform data
- *
- * @handle_irq: an optional handler which will be called from the
- *     interrupt and passed the address of the low level handler,
- *     and can be used to implement any platform specific handling
- *     before or after calling it.
- */
-struct arm_pmu_platdata {
-       irqreturn_t (*handle_irq)(int irq, void *dev,
-                                 irq_handler_t pmu_handler);
-};
-
-#ifdef CONFIG_HW_PERF_EVENTS
-
-/*
- * The ARMv7 CPU PMU supports up to 32 event counters.
- */
-#define ARMPMU_MAX_HWEVENTS            32
-
-#define HW_OP_UNSUPPORTED              0xFFFF
-#define C(_x)                          PERF_COUNT_HW_CACHE_##_x
-#define CACHE_OP_UNSUPPORTED           0xFFFF
-
-#define PERF_MAP_ALL_UNSUPPORTED                                       \
-       [0 ... PERF_COUNT_HW_MAX - 1] = HW_OP_UNSUPPORTED
-
-#define PERF_CACHE_MAP_ALL_UNSUPPORTED                                 \
-[0 ... C(MAX) - 1] = {                                                 \
-       [0 ... C(OP_MAX) - 1] = {                                       \
-               [0 ... C(RESULT_MAX) - 1] = CACHE_OP_UNSUPPORTED,       \
-       },                                                              \
-}
-
-/* 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[ARMPMU_MAX_HWEVENTS];
-
-       /*
-        * 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.
-        */
-       DECLARE_BITMAP(used_mask, ARMPMU_MAX_HWEVENTS);
-
-       /*
-        * Hardware lock to serialize accesses to PMU registers. Needed for the
-        * read/modify/write sequences.
-        */
-       raw_spinlock_t          pmu_lock;
-
-       /*
-        * When using percpu IRQs, we need a percpu dev_id. Place it here as we
-        * already have to allocate this struct per cpu.
-        */
-       struct arm_pmu          *percpu_pmu;
-};
-
-struct arm_pmu {
-       struct pmu      pmu;
-       cpumask_t       active_irqs;
-       cpumask_t       supported_cpus;
-       int             *irq_affinity;
-       char            *name;
-       irqreturn_t     (*handle_irq)(int irq_num, void *dev);
-       void            (*enable)(struct perf_event *event);
-       void            (*disable)(struct perf_event *event);
-       int             (*get_event_idx)(struct pmu_hw_events *hw_events,
-                                        struct perf_event *event);
-       void            (*clear_event_idx)(struct pmu_hw_events *hw_events,
-                                        struct perf_event *event);
-       int             (*set_event_filter)(struct hw_perf_event *evt,
-                                           struct perf_event_attr *attr);
-       u32             (*read_counter)(struct perf_event *event);
-       void            (*write_counter)(struct perf_event *event, u32 val);
-       void            (*start)(struct arm_pmu *);
-       void            (*stop)(struct arm_pmu *);
-       void            (*reset)(void *);
-       int             (*request_irq)(struct arm_pmu *, irq_handler_t handler);
-       void            (*free_irq)(struct arm_pmu *);
-       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    __percpu *hw_events;
-       struct notifier_block   hotplug_nb;
-};
-
-#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
-
-int armpmu_register(struct arm_pmu *armpmu, int type);
-
-u64 armpmu_event_update(struct perf_event *event);
-
-int armpmu_event_set_period(struct perf_event *event);
-
-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);
-
-struct pmu_probe_info {
-       unsigned int cpuid;
-       unsigned int mask;
-       int (*init)(struct arm_pmu *);
-};
-
-#define PMU_PROBE(_cpuid, _mask, _fn)  \
-{                                      \
-       .cpuid = (_cpuid),              \
-       .mask = (_mask),                \
-       .init = (_fn),                  \
-}
-
-#define ARM_PMU_PROBE(_cpuid, _fn) \
-       PMU_PROBE(_cpuid, ARM_CPU_PART_MASK, _fn)
-
-#define ARM_PMU_XSCALE_MASK    ((0xff << 24) | ARM_CPU_XSCALE_ARCH_MASK)
-
-#define XSCALE_PMU_PROBE(_version, _fn) \
-       PMU_PROBE(ARM_CPU_IMP_INTEL << 24 | _version, ARM_PMU_XSCALE_MASK, _fn)
-
-int arm_pmu_device_probe(struct platform_device *pdev,
-                        const struct of_device_id *of_table,
-                        const struct pmu_probe_info *probe_table);
-
-#endif /* CONFIG_HW_PERF_EVENTS */
-
-#endif /* __ARM_PMU_H__ */
index e69f7a1..fcb25c1 100644 (file)
@@ -71,8 +71,7 @@ obj-$(CONFIG_CPU_PJ4)         += pj4-cp0.o
 obj-$(CONFIG_CPU_PJ4B)         += pj4-cp0.o
 obj-$(CONFIG_IWMMXT)           += iwmmxt.o
 obj-$(CONFIG_PERF_EVENTS)      += perf_regs.o perf_callchain.o
-obj-$(CONFIG_HW_PERF_EVENTS)   += perf_event.o \
-                                  perf_event_xscale.o perf_event_v6.o \
+obj-$(CONFIG_HW_PERF_EVENTS)   += perf_event_xscale.o perf_event_v6.o \
                                   perf_event_v7.o
 CFLAGS_pj4-cp0.o               := -marm
 AFLAGS_iwmmxt.o                        := -Wa,-mcpu=iwmmxt
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
deleted file mode 100644 (file)
index 1cb4065..0000000
+++ /dev/null
@@ -1,921 +0,0 @@
-#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/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>
-
-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;
-}
index 09f83e4..09413e7 100644 (file)
@@ -34,9 +34,9 @@
 
 #include <asm/cputype.h>
 #include <asm/irq_regs.h>
-#include <asm/pmu.h>
 
 #include <linux/of.h>
+#include <linux/perf/arm_pmu.h>
 #include <linux/platform_device.h>
 
 enum armv6_perf_types {
index f9b37f8..126dc67 100644 (file)
 #include <asm/cp15.h>
 #include <asm/cputype.h>
 #include <asm/irq_regs.h>
-#include <asm/pmu.h>
 #include <asm/vfp.h>
 #include "../vfp/vfpinstr.h"
 
 #include <linux/of.h>
+#include <linux/perf/arm_pmu.h>
 #include <linux/platform_device.h>
 
 /*
index 304d056..aa0499e 100644 (file)
@@ -16,9 +16,9 @@
 
 #include <asm/cputype.h>
 #include <asm/irq_regs.h>
-#include <asm/pmu.h>
 
 #include <linux/of.h>
+#include <linux/perf/arm_pmu.h>
 #include <linux/platform_device.h>
 
 enum xscale_perf_types {
index 1691380..5578dc1 100644 (file)
 #include <linux/mfd/dbx500-prcmu.h>
 #include <linux/of.h>
 #include <linux/of_platform.h>
+#include <linux/perf/arm_pmu.h>
 #include <linux/regulator/machine.h>
 #include <linux/random.h>
 
-#include <asm/pmu.h>
 #include <asm/mach/map.h>
 
 #include "setup.h"
index 6e973b8..3497485 100644 (file)
@@ -176,6 +176,8 @@ source "drivers/powercap/Kconfig"
 
 source "drivers/mcb/Kconfig"
 
+source "drivers/perf/Kconfig"
+
 source "drivers/ras/Kconfig"
 
 source "drivers/thunderbolt/Kconfig"
index b64b49f..f245f22 100644 (file)
@@ -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 (file)
index 0000000..d9de36e
--- /dev/null
@@ -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 (file)
index 0000000..acd2397
--- /dev/null
@@ -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 (file)
index 0000000..2365a32
--- /dev/null
@@ -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;
+}
diff --git a/include/linux/perf/arm_pmu.h b/include/linux/perf/arm_pmu.h
new file mode 100644 (file)
index 0000000..bfa673b
--- /dev/null
@@ -0,0 +1,154 @@
+/*
+ *  linux/arch/arm/include/asm/pmu.h
+ *
+ *  Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
+ *
+ * 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.
+ *
+ */
+
+#ifndef __ARM_PMU_H__
+#define __ARM_PMU_H__
+
+#include <linux/interrupt.h>
+#include <linux/perf_event.h>
+
+#include <asm/cputype.h>
+
+/*
+ * struct arm_pmu_platdata - ARM PMU platform data
+ *
+ * @handle_irq: an optional handler which will be called from the
+ *     interrupt and passed the address of the low level handler,
+ *     and can be used to implement any platform specific handling
+ *     before or after calling it.
+ */
+struct arm_pmu_platdata {
+       irqreturn_t (*handle_irq)(int irq, void *dev,
+                                 irq_handler_t pmu_handler);
+};
+
+#ifdef CONFIG_ARM_PMU
+
+/*
+ * The ARMv7 CPU PMU supports up to 32 event counters.
+ */
+#define ARMPMU_MAX_HWEVENTS            32
+
+#define HW_OP_UNSUPPORTED              0xFFFF
+#define C(_x)                          PERF_COUNT_HW_CACHE_##_x
+#define CACHE_OP_UNSUPPORTED           0xFFFF
+
+#define PERF_MAP_ALL_UNSUPPORTED                                       \
+       [0 ... PERF_COUNT_HW_MAX - 1] = HW_OP_UNSUPPORTED
+
+#define PERF_CACHE_MAP_ALL_UNSUPPORTED                                 \
+[0 ... C(MAX) - 1] = {                                                 \
+       [0 ... C(OP_MAX) - 1] = {                                       \
+               [0 ... C(RESULT_MAX) - 1] = CACHE_OP_UNSUPPORTED,       \
+       },                                                              \
+}
+
+/* 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[ARMPMU_MAX_HWEVENTS];
+
+       /*
+        * 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.
+        */
+       DECLARE_BITMAP(used_mask, ARMPMU_MAX_HWEVENTS);
+
+       /*
+        * Hardware lock to serialize accesses to PMU registers. Needed for the
+        * read/modify/write sequences.
+        */
+       raw_spinlock_t          pmu_lock;
+
+       /*
+        * When using percpu IRQs, we need a percpu dev_id. Place it here as we
+        * already have to allocate this struct per cpu.
+        */
+       struct arm_pmu          *percpu_pmu;
+};
+
+struct arm_pmu {
+       struct pmu      pmu;
+       cpumask_t       active_irqs;
+       cpumask_t       supported_cpus;
+       int             *irq_affinity;
+       char            *name;
+       irqreturn_t     (*handle_irq)(int irq_num, void *dev);
+       void            (*enable)(struct perf_event *event);
+       void            (*disable)(struct perf_event *event);
+       int             (*get_event_idx)(struct pmu_hw_events *hw_events,
+                                        struct perf_event *event);
+       void            (*clear_event_idx)(struct pmu_hw_events *hw_events,
+                                        struct perf_event *event);
+       int             (*set_event_filter)(struct hw_perf_event *evt,
+                                           struct perf_event_attr *attr);
+       u32             (*read_counter)(struct perf_event *event);
+       void            (*write_counter)(struct perf_event *event, u32 val);
+       void            (*start)(struct arm_pmu *);
+       void            (*stop)(struct arm_pmu *);
+       void            (*reset)(void *);
+       int             (*request_irq)(struct arm_pmu *, irq_handler_t handler);
+       void            (*free_irq)(struct arm_pmu *);
+       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    __percpu *hw_events;
+       struct notifier_block   hotplug_nb;
+};
+
+#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
+
+int armpmu_register(struct arm_pmu *armpmu, int type);
+
+u64 armpmu_event_update(struct perf_event *event);
+
+int armpmu_event_set_period(struct perf_event *event);
+
+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);
+
+struct pmu_probe_info {
+       unsigned int cpuid;
+       unsigned int mask;
+       int (*init)(struct arm_pmu *);
+};
+
+#define PMU_PROBE(_cpuid, _mask, _fn)  \
+{                                      \
+       .cpuid = (_cpuid),              \
+       .mask = (_mask),                \
+       .init = (_fn),                  \
+}
+
+#define ARM_PMU_PROBE(_cpuid, _fn) \
+       PMU_PROBE(_cpuid, ARM_CPU_PART_MASK, _fn)
+
+#define ARM_PMU_XSCALE_MASK    ((0xff << 24) | ARM_CPU_XSCALE_ARCH_MASK)
+
+#define XSCALE_PMU_PROBE(_version, _fn) \
+       PMU_PROBE(ARM_CPU_IMP_INTEL << 24 | _version, ARM_PMU_XSCALE_MASK, _fn)
+
+int arm_pmu_device_probe(struct platform_device *pdev,
+                        const struct of_device_id *of_table,
+                        const struct pmu_probe_info *probe_table);
+
+#endif /* CONFIG_ARM_PMU */
+
+#endif /* __ARM_PMU_H__ */