arch/arm/include/asm/pmu.h

   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  */
  22 enum 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
  31  *      interrupt and passed the address of the low level handler,
  32  *      and can be used to implement any platform specific handling
  33  *      before or after calling it.
  34  * @enable_irq: an optional handler which will be called after
  35  *      request_irq and be used to handle some platform specific
  36  *      irq enablement
  37  * @disable_irq: an optional handler which will be called before
  38  *      free_irq and be used to handle some platform specific
  39  *      irq disablement
  40  */
  41 struct arm_pmu_platdata {
  42         irqreturn_t (*handle_irq)(int irq, void *dev,
  43                                   irq_handler_t pmu_handler);
  44         void (*enable_irq)(int irq);
  45         void (*disable_irq)(int irq);
  46 };
  47
  48 #ifdef CONFIG_CPU_HAS_PMU
  49
  50 /**
  51  * reserve_pmu() - reserve the hardware performance counters
  52  *
  53  * Reserve the hardware performance counters in the system for exclusive use.
  54  * Returns 0 on success or -EBUSY if the lock is already held.
  55  */
  56 extern int
  57 reserve_pmu(enum arm_pmu_type type);
  58
  59 /**
  60  * release_pmu() - Relinquish control of the performance counters
  61  *
  62  * Release the performance counters and allow someone else to use them.
  63  */
  64 extern void
  65 release_pmu(enum arm_pmu_type type);
  66
  67 #else /* CONFIG_CPU_HAS_PMU */
  68
  69 #include <linux/err.h>
  70
  71 static inline int
  72 reserve_pmu(enum arm_pmu_type type)
  73 {
  74         return -ENODEV;
  75 }
  76
  77 static inline void
  78 release_pmu(enum arm_pmu_type type)     { }
  79
  80 #endif /* CONFIG_CPU_HAS_PMU */
  81
  82 #ifdef CONFIG_HW_PERF_EVENTS
  83
  84 /* The events for a given PMU register set. */
  85 struct pmu_hw_events {
  86         /*
  87          * The events that are active on the PMU for the given index.
  88          */
  89         struct perf_event       **events;
  90
  91         /*
  92          * A 1 bit for an index indicates that the counter is being used for
  93          * an event. A 0 means that the counter can be used.
  94          */
  95         unsigned long           *used_mask;
  96
  97         /*
  98          * Hardware lock to serialize accesses to PMU registers. Needed for the
  99          * read/modify/write sequences.
 100          */
 101         raw_spinlock_t          pmu_lock;
 102 };
 103
 104 struct arm_pmu {
 105         struct pmu      pmu;
 106         enum arm_pmu_type type;
 107         cpumask_t       active_irqs;
 108         char            *name;
 109         irqreturn_t     (*handle_irq)(int irq_num, void *dev);
 110         void            (*enable)(struct hw_perf_event *evt, int idx);
 111         void            (*disable)(struct hw_perf_event *evt, int idx);
 112         int             (*get_event_idx)(struct pmu_hw_events *hw_events,
 113                                          struct hw_perf_event *hwc);
 114         int             (*set_event_filter)(struct hw_perf_event *evt,
 115                                             struct perf_event_attr *attr);
 116         u32             (*read_counter)(int idx);
 117         void            (*write_counter)(int idx, u32 val);
 118         void            (*start)(void);
 119         void            (*stop)(void);
 120         void            (*reset)(void *);
 121         int             (*map_event)(struct perf_event *event);
 122         int             num_events;
 123         atomic_t        active_events;
 124         struct mutex    reserve_mutex;
 125         u64             max_period;
 126         struct platform_device  *plat_device;
 127         struct pmu_hw_events    *(*get_hw_events)(void);
 128 };
 129
 130 #define to_arm_pmu(p) (container_of(p, struct arm_pmu, pmu))
 131
 132 int __init armpmu_register(struct arm_pmu *armpmu, char *name, int type);
 133
 134 u64 armpmu_event_update(struct perf_event *event,
 135                         struct hw_perf_event *hwc,
 136                         int idx);
 137
 138 int armpmu_event_set_period(struct perf_event *event,
 139                             struct hw_perf_event *hwc,
 140                             int idx);
 141
 142 #endif /* CONFIG_HW_PERF_EVENTS */
 143
 144 #endif /* __ARM_PMU_H__ */