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
17enum arm_pmu_type {
18	ARM_PMU_DEVICE_CPU	= 0,
19	ARM_NUM_PMU_DEVICES,
20};
21
22/*
23 * struct arm_pmu_platdata - ARM PMU platform data
24 *
25 * @handle_irq: an optional handler which will be called from the interrupt and
26 * passed the address of the low level handler, and can be used to implement
27 * any platform specific handling before or after calling it.
28 */
29struct arm_pmu_platdata {
30	irqreturn_t (*handle_irq)(int irq, void *dev,
31				  irq_handler_t pmu_handler);
32};
33
34#ifdef CONFIG_CPU_HAS_PMU
35
36/**
37 * reserve_pmu() - reserve the hardware performance counters
38 *
39 * Reserve the hardware performance counters in the system for exclusive use.
40 * The platform_device for the system is returned on success, ERR_PTR()
41 * encoded error on failure.
42 */
43extern struct platform_device *
44reserve_pmu(enum arm_pmu_type type);
45
46/**
47 * release_pmu() - Relinquish control of the performance counters
48 *
49 * Release the performance counters and allow someone else to use them.
50 * Callers must have disabled the counters and released IRQs before calling
51 * this. The platform_device returned from reserve_pmu() must be passed as
52 * a cookie.
53 */
54extern int
55release_pmu(enum arm_pmu_type type);
56
57/**
58 * init_pmu() - Initialise the PMU.
59 *
60 * Initialise the system ready for PMU enabling. This should typically set the
61 * IRQ affinity and nothing else. The users (oprofile/perf events etc) will do
62 * the actual hardware initialisation.
63 */
64extern int
65init_pmu(enum arm_pmu_type type);
66
67#else /* CONFIG_CPU_HAS_PMU */
68
69#include <linux/err.h>
70
71static inline struct platform_device *
72reserve_pmu(enum arm_pmu_type type)
73{
74	return ERR_PTR(-ENODEV);
75}
76
77static inline int
78release_pmu(enum arm_pmu_type type)
79{
80	return -ENODEV;
81}
82
83static inline int
84init_pmu(enum arm_pmu_type type)
85{
86	return -ENODEV;
87}
88
89#endif /* CONFIG_CPU_HAS_PMU */
90
91#endif /* __ARM_PMU_H__ */