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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1/*
2 * linux/arch/arm/include/asm/pmu.h
3 *
4 * Copyright (C) 2009 picoChip Designs Ltd, Jamie Iles
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 */
11
12#ifndef __ARM_PMU_H__
13#define __ARM_PMU_H__
14
15#include <linux/interrupt.h>
16#include <linux/perf_event.h>
17
18/*
19 * Types of PMUs that can be accessed directly and require mutual
20 * exclusion between profiling tools.
21 */
22enum arm_pmu_type {
23 ARM_PMU_DEVICE_CPU = 0,
24 ARM_NUM_PMU_DEVICES,
25};
26
27/*
28 * struct arm_pmu_platdata - ARM PMU platform data
29 *
30 * @handle_irq: an optional handler which will be called from the interrupt and
31 * passed the address of the low level handler, and can be used to implement
32 * any platform specific handling before or after calling it.
33 */
34struct arm_pmu_platdata {
35 irqreturn_t (*handle_irq)(int irq, void *dev,
36 irq_handler_t pmu_handler);
37};
38
39#ifdef CONFIG_CPU_HAS_PMU
40
41/**
42 * reserve_pmu() - reserve the hardware performance counters
43 *
44 * Reserve the hardware performance counters in the system for exclusive use.
45 * Returns 0 on success or -EBUSY if the lock is already held.
46 */
47extern int
48reserve_pmu(enum arm_pmu_type type);
49
50/**
51 * release_pmu() - Relinquish control of the performance counters
52 *
53 * Release the performance counters and allow someone else to use them.
54 */
55extern void
56release_pmu(enum arm_pmu_type type);
57
58/**
59 * init_pmu() - Initialise the PMU.
60 *
61 * Initialise the system ready for PMU enabling. This should typically set the
62 * IRQ affinity and nothing else. The users (oprofile/perf events etc) will do
63 * the actual hardware initialisation.
64 */
65extern int
66init_pmu(enum arm_pmu_type type);
67
68#else /* CONFIG_CPU_HAS_PMU */
69
70#include <linux/err.h>
71
72static inline int
73reserve_pmu(enum arm_pmu_type type)
74{
75 return -ENODEV;
76}
77
78static inline void
79release_pmu(enum arm_pmu_type type) { }
80
81#endif /* CONFIG_CPU_HAS_PMU */
82
83#ifdef CONFIG_HW_PERF_EVENTS
84
85/* The events for a given PMU register set. */
86struct pmu_hw_events {
87 /*
88 * The events that are active on the PMU for the given index.
89 */
90 struct perf_event **events;
91
92 /*
93 * A 1 bit for an index indicates that the counter is being used for
94 * an event. A 0 means that the counter can be used.
95 */
96 unsigned long *used_mask;
97
98 /*
99 * Hardware lock to serialize accesses to PMU registers. Needed for the
100 * read/modify/write sequences.
101 */
102 raw_spinlock_t pmu_lock;
103};
104
105struct arm_pmu {
106 struct pmu pmu;
107 enum arm_perf_pmu_ids id;
108 enum arm_pmu_type type;
109 cpumask_t active_irqs;
110 const char *name;
111 irqreturn_t (*handle_irq)(int irq_num, void *dev);
112 void (*enable)(struct hw_perf_event *evt, int idx);
113 void (*disable)(struct hw_perf_event *evt, int idx);
114 int (*get_event_idx)(struct pmu_hw_events *hw_events,
115 struct hw_perf_event *hwc);
116 int (*set_event_filter)(struct hw_perf_event *evt,
117 struct perf_event_attr *attr);
118 u32 (*read_counter)(int idx);
119 void (*write_counter)(int idx, u32 val);
120 void (*start)(void);
121 void (*stop)(void);
122 void (*reset)(void *);
123 int (*map_event)(struct perf_event *event);
124 int num_events;
125 atomic_t active_events;
126 struct mutex reserve_mutex;
127 u64 max_period;
128 struct platform_device *plat_device;
129 struct pmu_hw_events *(*get_hw_events)(void);
130};
131
132#define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
133
134int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type);
135
136u64 armpmu_event_update(struct perf_event *event,
137 struct hw_perf_event *hwc,
138 int idx, int overflow);
139
140int armpmu_event_set_period(struct perf_event *event,
141 struct hw_perf_event *hwc,
142 int idx);
143
144#endif /* CONFIG_HW_PERF_EVENTS */
145
146#endif /* __ARM_PMU_H__ */