/*
 * Linux performance counter support for MIPS.
 *
 * Copyright (C) 2010 MIPS Technologies, Inc.
 * Copyright (C) 2011 Cavium Networks, Inc.
 * Author: Deng-Cheng Zhu
 *
 * This code is based on the implementation for ARM, which is in turn
 * based on the sparc64 perf event code and the x86 code. Performance
 * counter access is based on the MIPS Oprofile code. And the callchain
 * support references the code of MIPS stacktrace.c.
 *
 * 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.
 */

#include <linux/cpumask.h>
#include <linux/interrupt.h>
#include <linux/smp.h>
#include <linux/kernel.h>
#include <linux/perf_event.h>
#include <linux/uaccess.h>

#include <asm/irq.h>
#include <asm/irq_regs.h>
#include <asm/stacktrace.h>
#include <asm/time.h> /* For perf_irq */

#define MIPS_MAX_HWEVENTS 4
#define MIPS_TCS_PER_COUNTER 2
#define MIPS_CPUID_TO_COUNTER_MASK (MIPS_TCS_PER_COUNTER - 1)

struct cpu_hw_events {
        /* Array of events on this cpu. */
        struct perf_event       *events[MIPS_MAX_HWEVENTS];

        /*
         * Set the bit (indexed by the counter number) when the counter
         * is used for an event.
         */
        unsigned long           used_mask[BITS_TO_LONGS(MIPS_MAX_HWEVENTS)];

        /*
         * Software copy of the control register for each performance counter.
         * MIPS CPUs vary in performance counters. They use this differently,
         * and even may not use it.
         */
        unsigned int            saved_ctrl[MIPS_MAX_HWEVENTS];
};
DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
        .saved_ctrl = {0},
};

/* The description of MIPS performance events. */
struct mips_perf_event {
        unsigned int event_id;
        /*
         * MIPS performance counters are indexed starting from 0.
         * CNTR_EVEN indicates the indexes of the counters to be used are
         * even numbers.
         */
        unsigned int cntr_mask;
        #define CNTR_EVEN       0x55555555
        #define CNTR_ODD        0xaaaaaaaa
        #define CNTR_ALL        0xffffffff
#ifdef CONFIG_MIPS_MT_SMP
        enum {
                T  = 0,
                V  = 1,
                P  = 2,
        } range;
#else
        #define T
        #define V
        #define P
#endif
};

static struct mips_perf_event raw_event;
static DEFINE_MUTEX(raw_event_mutex);

#define C(x) PERF_COUNT_HW_CACHE_##x

struct mips_pmu {
        u64             max_period;
        u64             valid_count;
        u64             overflow;
        const char      *name;
        int             irq;
        u64             (*read_counter)(unsigned int idx);
        void            (*write_counter)(unsigned int idx, u64 val);
        const struct mips_perf_event *(*map_raw_event)(u64 config);
        const struct mips_perf_event (*general_event_map)[PERF_COUNT_HW_MAX];
        const struct mips_perf_event (*cache_event_map)
                                [PERF_COUNT_HW_CACHE_MAX]
                                [PERF_COUNT_HW_CACHE_OP_MAX]
                                [PERF_COUNT_HW_CACHE_RESULT_MAX];
        unsigned int    num_counters;
};

static struct mips_pmu mipspmu;

#define M_PERFCTL_EVENT(event)          (((event) << MIPS_PERFCTRL_EVENT_S) & \
                                         MIPS_PERFCTRL_EVENT)
#define M_PERFCTL_VPEID(vpe)            ((vpe)    << MIPS_PERFCTRL_VPEID_S)

#ifdef CONFIG_CPU_BMIPS5000
#define M_PERFCTL_MT_EN(filter)         0
#else /* !CONFIG_CPU_BMIPS5000 */
#define M_PERFCTL_MT_EN(filter)         (filter)
#endif /* CONFIG_CPU_BMIPS5000 */

#define    M_TC_EN_ALL                  M_PERFCTL_MT_EN(MIPS_PERFCTRL_MT_EN_ALL)
#define    M_TC_EN_VPE                  M_PERFCTL_MT_EN(MIPS_PERFCTRL_MT_EN_VPE)
#define    M_TC_EN_TC                   M_PERFCTL_MT_EN(MIPS_PERFCTRL_MT_EN_TC)

#define M_PERFCTL_COUNT_EVENT_WHENEVER  (MIPS_PERFCTRL_EXL |            \
                                         MIPS_PERFCTRL_K |              \
                                         MIPS_PERFCTRL_U |              \
                                         MIPS_PERFCTRL_S |              \
                                         MIPS_PERFCTRL_IE)

#ifdef CONFIG_MIPS_MT_SMP
#define M_PERFCTL_CONFIG_MASK           0x3fff801f
#else
#define M_PERFCTL_CONFIG_MASK           0x1f
#endif


#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
static DEFINE_RWLOCK(pmuint_rwlock);

#if defined(CONFIG_CPU_BMIPS5000)
#define vpe_id()        (cpu_has_mipsmt_pertccounters ? \
                         0 : (smp_processor_id() & MIPS_CPUID_TO_COUNTER_MASK))
#else
#define vpe_id()        (cpu_has_mipsmt_pertccounters ? \
                         0 : cpu_vpe_id(&current_cpu_data))
#endif

/* Copied from op_model_mipsxx.c */
static unsigned int vpe_shift(void)
{
        if (num_possible_cpus() > 1)
                return 1;

        return 0;
}

static unsigned int counters_total_to_per_cpu(unsigned int counters)
{
        return counters >> vpe_shift();
}

#else /* !CONFIG_MIPS_PERF_SHARED_TC_COUNTERS */
#define vpe_id()        0

#endif /* CONFIG_MIPS_PERF_SHARED_TC_COUNTERS */

static void resume_local_counters(void);
static void pause_local_counters(void);
static irqreturn_t mipsxx_pmu_handle_irq(int, void *);
static int mipsxx_pmu_handle_shared_irq(void);

static unsigned int mipsxx_pmu_swizzle_perf_idx(unsigned int idx)
{
        if (vpe_id() == 1)
                idx = (idx + 2) & 3;
        return idx;
}

static u64 mipsxx_pmu_read_counter(unsigned int idx)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                /*
                 * The counters are unsigned, we must cast to truncate
                 * off the high bits.
                 */
                return (u32)read_c0_perfcntr0();
        case 1:
                return (u32)read_c0_perfcntr1();
        case 2:
                return (u32)read_c0_perfcntr2();
        case 3:
                return (u32)read_c0_perfcntr3();
        default:
                WARN_ONCE(1, "Invalid performance counter number (%d)\n", idx);
                return 0;
        }
}

static u64 mipsxx_pmu_read_counter_64(unsigned int idx)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                return read_c0_perfcntr0_64();
        case 1:
                return read_c0_perfcntr1_64();
        case 2:
                return read_c0_perfcntr2_64();
        case 3:
                return read_c0_perfcntr3_64();
        default:
                WARN_ONCE(1, "Invalid performance counter number (%d)\n", idx);
                return 0;
        }
}

static void mipsxx_pmu_write_counter(unsigned int idx, u64 val)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                write_c0_perfcntr0(val);
                return;
        case 1:
                write_c0_perfcntr1(val);
                return;
        case 2:
                write_c0_perfcntr2(val);
                return;
        case 3:
                write_c0_perfcntr3(val);
                return;
        }
}

static void mipsxx_pmu_write_counter_64(unsigned int idx, u64 val)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                write_c0_perfcntr0_64(val);
                return;
        case 1:
                write_c0_perfcntr1_64(val);
                return;
        case 2:
                write_c0_perfcntr2_64(val);
                return;
        case 3:
                write_c0_perfcntr3_64(val);
                return;
        }
}

static unsigned int mipsxx_pmu_read_control(unsigned int idx)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                return read_c0_perfctrl0();
        case 1:
                return read_c0_perfctrl1();
        case 2:
                return read_c0_perfctrl2();
        case 3:
                return read_c0_perfctrl3();
        default:
                WARN_ONCE(1, "Invalid performance counter number (%d)\n", idx);
                return 0;
        }
}

static void mipsxx_pmu_write_control(unsigned int idx, unsigned int val)
{
        idx = mipsxx_pmu_swizzle_perf_idx(idx);

        switch (idx) {
        case 0:
                write_c0_perfctrl0(val);
                return;
        case 1:
                write_c0_perfctrl1(val);
                return;
        case 2:
                write_c0_perfctrl2(val);
                return;
        case 3:
                write_c0_perfctrl3(val);
                return;
        }
}

static int mipsxx_pmu_alloc_counter(struct cpu_hw_events *cpuc,
                                    struct hw_perf_event *hwc)
{
        int i;

        /*
         * We only need to care the counter mask. The range has been
         * checked definitely.
         */
        unsigned long cntr_mask = (hwc->event_base >> 8) & 0xffff;

        for (i = mipspmu.num_counters - 1; i >= 0; i--) {
                /*
                 * Note that some MIPS perf events can be counted by both
                 * even and odd counters, wheresas many other are only by
                 * even _or_ odd counters. This introduces an issue that
                 * when the former kind of event takes the counter the
                 * latter kind of event wants to use, then the "counter
                 * allocation" for the latter event will fail. In fact if
                 * they can be dynamically swapped, they both feel happy.
                 * But here we leave this issue alone for now.
                 */
                if (test_bit(i, &cntr_mask) &&
                        !test_and_set_bit(i, cpuc->used_mask))
                        return i;
        }

        return -EAGAIN;
}

static void mipsxx_pmu_enable_event(struct hw_perf_event *evt, int idx)
{
        struct perf_event *event = container_of(evt, struct perf_event, hw);
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
#ifdef CONFIG_MIPS_MT_SMP
        unsigned int range = evt->event_base >> 24;
#endif /* CONFIG_MIPS_MT_SMP */

        WARN_ON(idx < 0 || idx >= mipspmu.num_counters);

        cpuc->saved_ctrl[idx] = M_PERFCTL_EVENT(evt->event_base & 0xff) |
                (evt->config_base & M_PERFCTL_CONFIG_MASK) |
                /* Make sure interrupt enabled. */
                MIPS_PERFCTRL_IE;

#ifdef CONFIG_CPU_BMIPS5000
        {
                /* enable the counter for the calling thread */
                cpuc->saved_ctrl[idx] |=
                        (1 << (12 + vpe_id())) | BRCM_PERFCTRL_TC;
        }
#else
#ifdef CONFIG_MIPS_MT_SMP
        if (range > V) {
                /* The counter is processor wide. Set it up to count all TCs. */
                pr_debug("Enabling perf counter for all TCs\n");
                cpuc->saved_ctrl[idx] |= M_TC_EN_ALL;
        } else
#endif /* CONFIG_MIPS_MT_SMP */
        {
                unsigned int cpu, ctrl;

                /*
                 * Set up the counter for a particular CPU when event->cpu is
                 * a valid CPU number. Otherwise set up the counter for the CPU
                 * scheduling this thread.
                 */
                cpu = (event->cpu >= 0) ? event->cpu : smp_processor_id();

                ctrl = M_PERFCTL_VPEID(cpu_vpe_id(&cpu_data[cpu]));
                ctrl |= M_TC_EN_VPE;
                cpuc->saved_ctrl[idx] |= ctrl;
                pr_debug("Enabling perf counter for CPU%d\n", cpu);
        }
#endif /* CONFIG_CPU_BMIPS5000 */
        /*
         * We do not actually let the counter run. Leave it until start().
         */
}

static void mipsxx_pmu_disable_event(int idx)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        unsigned long flags;

        WARN_ON(idx < 0 || idx >= mipspmu.num_counters);

        local_irq_save(flags);
        cpuc->saved_ctrl[idx] = mipsxx_pmu_read_control(idx) &
                ~M_PERFCTL_COUNT_EVENT_WHENEVER;
        mipsxx_pmu_write_control(idx, cpuc->saved_ctrl[idx]);
        local_irq_restore(flags);
}

static int mipspmu_event_set_period(struct perf_event *event,
                                    struct hw_perf_event *hwc,
                                    int idx)
{
        u64 left = local64_read(&hwc->period_left);
        u64 period = hwc->sample_period;
        int ret = 0;

        if (unlikely((left + period) & (1ULL << 63))) {
                /* left underflowed by more than period. */
                left = period;
                local64_set(&hwc->period_left, left);
                hwc->last_period = period;
                ret = 1;
        } else  if (unlikely((left + period) <= period)) {
                /* left underflowed by less than period. */
                left += period;
                local64_set(&hwc->period_left, left);
                hwc->last_period = period;
                ret = 1;
        }

        if (left > mipspmu.max_period) {
                left = mipspmu.max_period;
                local64_set(&hwc->period_left, left);
        }

        local64_set(&hwc->prev_count, mipspmu.overflow - left);

        mipspmu.write_counter(idx, mipspmu.overflow - left);

        perf_event_update_userpage(event);

        return ret;
}

static void mipspmu_event_update(struct perf_event *event,
                                 struct hw_perf_event *hwc,
                                 int idx)
{
        u64 prev_raw_count, new_raw_count;
        u64 delta;

again:
        prev_raw_count = local64_read(&hwc->prev_count);
        new_raw_count = mipspmu.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;

        local64_add(delta, &event->count);
        local64_sub(delta, &hwc->period_left);
}

static void mipspmu_start(struct perf_event *event, int flags)
{
        struct hw_perf_event *hwc = &event->hw;

        if (flags & PERF_EF_RELOAD)
                WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));

        hwc->state = 0;

        /* Set the period for the event. */
        mipspmu_event_set_period(event, hwc, hwc->idx);

        /* Enable the event. */
        mipsxx_pmu_enable_event(hwc, hwc->idx);
}

static void mipspmu_stop(struct perf_event *event, int flags)
{
        struct hw_perf_event *hwc = &event->hw;

        if (!(hwc->state & PERF_HES_STOPPED)) {
                /* We are working on a local event. */
                mipsxx_pmu_disable_event(hwc->idx);
                barrier();
                mipspmu_event_update(event, hwc, hwc->idx);
                hwc->state |= PERF_HES_STOPPED | PERF_HES_UPTODATE;
        }
}

static int mipspmu_add(struct perf_event *event, int flags)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        struct hw_perf_event *hwc = &event->hw;
        int idx;
        int err = 0;

        perf_pmu_disable(event->pmu);

        /* To look for a free counter for this event. */
        idx = mipsxx_pmu_alloc_counter(cpuc, 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;
        mipsxx_pmu_disable_event(idx);
        cpuc->events[idx] = event;

        hwc->state = PERF_HES_STOPPED | PERF_HES_UPTODATE;
        if (flags & PERF_EF_START)
                mipspmu_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 void mipspmu_del(struct perf_event *event, int flags)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        struct hw_perf_event *hwc = &event->hw;
        int idx = hwc->idx;

        WARN_ON(idx < 0 || idx >= mipspmu.num_counters);

        mipspmu_stop(event, PERF_EF_UPDATE);
        cpuc->events[idx] = NULL;
        clear_bit(idx, cpuc->used_mask);

        perf_event_update_userpage(event);
}

static void mipspmu_read(struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;

        /* Don't read disabled counters! */
        if (hwc->idx < 0)
                return;

        mipspmu_event_update(event, hwc, hwc->idx);
}

static void mipspmu_enable(struct pmu *pmu)
{
#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
        write_unlock(&pmuint_rwlock);
#endif
        resume_local_counters();
}

/*
 * MIPS performance counters can be per-TC. The control registers can
 * not be directly accessed across CPUs. Hence if we want to do global
 * control, we need cross CPU calls. on_each_cpu() can help us, but we
 * can not make sure this function is called with interrupts enabled. So
 * here we pause local counters and then grab a rwlock and leave the
 * counters on other CPUs alone. If any counter interrupt raises while
 * we own the write lock, simply pause local counters on that CPU and
 * spin in the handler. Also we know we won't be switched to another
 * CPU after pausing local counters and before grabbing the lock.
 */
static void mipspmu_disable(struct pmu *pmu)
{
        pause_local_counters();
#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
        write_lock(&pmuint_rwlock);
#endif
}

static atomic_t active_events = ATOMIC_INIT(0);
static DEFINE_MUTEX(pmu_reserve_mutex);
static int (*save_perf_irq)(void);

static int mipspmu_get_irq(void)
{
        int err;

        if (mipspmu.irq >= 0) {
                /* Request my own irq handler. */
                err = request_irq(mipspmu.irq, mipsxx_pmu_handle_irq,
                                  IRQF_PERCPU | IRQF_NOBALANCING |
                                  IRQF_NO_THREAD | IRQF_NO_SUSPEND |
                                  IRQF_SHARED,
                                  "mips_perf_pmu", &mipspmu);
                if (err) {
                        pr_warn("Unable to request IRQ%d for MIPS performance counters!\n",
                                mipspmu.irq);
                }
        } else if (cp0_perfcount_irq < 0) {
                /*
                 * We are sharing the irq number with the timer interrupt.
                 */
                save_perf_irq = perf_irq;
                perf_irq = mipsxx_pmu_handle_shared_irq;
                err = 0;
        } else {
                pr_warn("The platform hasn't properly defined its interrupt controller\n");
                err = -ENOENT;
        }

        return err;
}

static void mipspmu_free_irq(void)
{
        if (mipspmu.irq >= 0)
                free_irq(mipspmu.irq, &mipspmu);
        else if (cp0_perfcount_irq < 0)
                perf_irq = save_perf_irq;
}

/*
 * mipsxx/rm9000/loongson2 have different performance counters, they have
 * specific low-level init routines.
 */
static void reset_counters(void *arg);
static int __hw_perf_event_init(struct perf_event *event);

static void hw_perf_event_destroy(struct perf_event *event)
{
        if (atomic_dec_and_mutex_lock(&active_events,
                                &pmu_reserve_mutex)) {
                /*
                 * We must not call the destroy function with interrupts
                 * disabled.
                 */
                on_each_cpu(reset_counters,
                        (void *)(long)mipspmu.num_counters, 1);
                mipspmu_free_irq();
                mutex_unlock(&pmu_reserve_mutex);
        }
}

static int mipspmu_event_init(struct perf_event *event)
{
        int err = 0;

        /* does not support taken branch sampling */
        if (has_branch_stack(event))
                return -EOPNOTSUPP;

        switch (event->attr.type) {
        case PERF_TYPE_RAW:
        case PERF_TYPE_HARDWARE:
        case PERF_TYPE_HW_CACHE:
                break;

        default:
                return -ENOENT;
        }

        if (event->cpu >= 0 && !cpu_online(event->cpu))
                return -ENODEV;

        if (!atomic_inc_not_zero(&active_events)) {
                mutex_lock(&pmu_reserve_mutex);
                if (atomic_read(&active_events) == 0)
                        err = mipspmu_get_irq();

                if (!err)
                        atomic_inc(&active_events);
                mutex_unlock(&pmu_reserve_mutex);
        }

        if (err)
                return err;

        return __hw_perf_event_init(event);
}

static struct pmu pmu = {
        .pmu_enable     = mipspmu_enable,
        .pmu_disable    = mipspmu_disable,
        .event_init     = mipspmu_event_init,
        .add            = mipspmu_add,
        .del            = mipspmu_del,
        .start          = mipspmu_start,
        .stop           = mipspmu_stop,
        .read           = mipspmu_read,
};

static unsigned int mipspmu_perf_event_encode(const struct mips_perf_event *pev)
{
/*
 * Top 8 bits for range, next 16 bits for cntr_mask, lowest 8 bits for
 * event_id.
 */
#ifdef CONFIG_MIPS_MT_SMP
        if (num_possible_cpus() > 1)
                return ((unsigned int)pev->range << 24) |
                        (pev->cntr_mask & 0xffff00) |
                        (pev->event_id & 0xff);
        else
#endif /* CONFIG_MIPS_MT_SMP */
                return ((pev->cntr_mask & 0xffff00) |
                        (pev->event_id & 0xff));
}

static const struct mips_perf_event *mipspmu_map_general_event(int idx)
{

        if ((*mipspmu.general_event_map)[idx].cntr_mask == 0)
                return ERR_PTR(-EOPNOTSUPP);
        return &(*mipspmu.general_event_map)[idx];
}

static const struct mips_perf_event *mipspmu_map_cache_event(u64 config)
{
        unsigned int cache_type, cache_op, cache_result;
        const struct mips_perf_event *pev;

        cache_type = (config >> 0) & 0xff;
        if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
                return ERR_PTR(-EINVAL);

        cache_op = (config >> 8) & 0xff;
        if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
                return ERR_PTR(-EINVAL);

        cache_result = (config >> 16) & 0xff;
        if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
                return ERR_PTR(-EINVAL);

        pev = &((*mipspmu.cache_event_map)
                                        [cache_type]
                                        [cache_op]
                                        [cache_result]);

        if (pev->cntr_mask == 0)
                return ERR_PTR(-EOPNOTSUPP);

        return pev;

}

static int validate_group(struct perf_event *event)
{
        struct perf_event *sibling, *leader = event->group_leader;
        struct cpu_hw_events fake_cpuc;

        memset(&fake_cpuc, 0, sizeof(fake_cpuc));

        if (mipsxx_pmu_alloc_counter(&fake_cpuc, &leader->hw) < 0)
                return -EINVAL;

        for_each_sibling_event(sibling, leader) {
                if (mipsxx_pmu_alloc_counter(&fake_cpuc, &sibling->hw) < 0)
                        return -EINVAL;
        }

        if (mipsxx_pmu_alloc_counter(&fake_cpuc, &event->hw) < 0)
                return -EINVAL;

        return 0;
}

/* This is needed by specific irq handlers in perf_event_*.c */
static void handle_associated_event(struct cpu_hw_events *cpuc,
                                    int idx, struct perf_sample_data *data,
                                    struct pt_regs *regs)
{
        struct perf_event *event = cpuc->events[idx];
        struct hw_perf_event *hwc = &event->hw;

        mipspmu_event_update(event, hwc, idx);
        data->period = event->hw.last_period;
        if (!mipspmu_event_set_period(event, hwc, idx))
                return;

        if (perf_event_overflow(event, data, regs))
                mipsxx_pmu_disable_event(idx);
}


static int __n_counters(void)
{
        if (!cpu_has_perf)
                return 0;
        if (!(read_c0_perfctrl0() & MIPS_PERFCTRL_M))
                return 1;
        if (!(read_c0_perfctrl1() & MIPS_PERFCTRL_M))
                return 2;
        if (!(read_c0_perfctrl2() & MIPS_PERFCTRL_M))
                return 3;

        return 4;
}

static int n_counters(void)
{
        int counters;

        switch (current_cpu_type()) {
        case CPU_R10000:
                counters = 2;
                break;

        case CPU_R12000:
        case CPU_R14000:
        case CPU_R16000:
                counters = 4;
                break;

        default:
                counters = __n_counters();
        }

        return counters;
}

static void reset_counters(void *arg)
{
        int counters = (int)(long)arg;
        switch (counters) {
        case 4:
                mipsxx_pmu_write_control(3, 0);
                mipspmu.write_counter(3, 0);
        case 3:
                mipsxx_pmu_write_control(2, 0);
                mipspmu.write_counter(2, 0);
        case 2:
                mipsxx_pmu_write_control(1, 0);
                mipspmu.write_counter(1, 0);
        case 1:
                mipsxx_pmu_write_control(0, 0);
                mipspmu.write_counter(0, 0);
        }
}

/* 24K/34K/1004K/interAptiv/loongson1 cores share the same event map. */
static const struct mips_perf_event mipsxxcore_event_map
                                [PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x00, CNTR_EVEN | CNTR_ODD, P },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x01, CNTR_EVEN | CNTR_ODD, T },
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x02, CNTR_EVEN, T },
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x02, CNTR_ODD, T },
};

/* 74K/proAptiv core has different branch event code. */
static const struct mips_perf_event mipsxxcore_event_map2
                                [PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x00, CNTR_EVEN | CNTR_ODD, P },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x01, CNTR_EVEN | CNTR_ODD, T },
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x27, CNTR_EVEN, T },
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x27, CNTR_ODD, T },
};

static const struct mips_perf_event i6x00_event_map[PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES]          = { 0x00, CNTR_EVEN | CNTR_ODD },
        [PERF_COUNT_HW_INSTRUCTIONS]        = { 0x01, CNTR_EVEN | CNTR_ODD },
        /* These only count dcache, not icache */
        [PERF_COUNT_HW_CACHE_REFERENCES]    = { 0x45, CNTR_EVEN | CNTR_ODD },
        [PERF_COUNT_HW_CACHE_MISSES]        = { 0x48, CNTR_EVEN | CNTR_ODD },
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x15, CNTR_EVEN | CNTR_ODD },
        [PERF_COUNT_HW_BRANCH_MISSES]       = { 0x16, CNTR_EVEN | CNTR_ODD },
};

static const struct mips_perf_event loongson3_event_map[PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x00, CNTR_EVEN },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x00, CNTR_ODD },
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x01, CNTR_EVEN },
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x01, CNTR_ODD },
};

static const struct mips_perf_event octeon_event_map[PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x01, CNTR_ALL },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x03, CNTR_ALL },
        [PERF_COUNT_HW_CACHE_REFERENCES] = { 0x2b, CNTR_ALL },
        [PERF_COUNT_HW_CACHE_MISSES] = { 0x2e, CNTR_ALL  },
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x08, CNTR_ALL },
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x09, CNTR_ALL },
        [PERF_COUNT_HW_BUS_CYCLES] = { 0x25, CNTR_ALL },
};

static const struct mips_perf_event bmips5000_event_map
                                [PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x00, CNTR_EVEN | CNTR_ODD, T },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x01, CNTR_EVEN | CNTR_ODD, T },
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x02, CNTR_ODD, T },
};

static const struct mips_perf_event xlp_event_map[PERF_COUNT_HW_MAX] = {
        [PERF_COUNT_HW_CPU_CYCLES] = { 0x01, CNTR_ALL },
        [PERF_COUNT_HW_INSTRUCTIONS] = { 0x18, CNTR_ALL }, /* PAPI_TOT_INS */
        [PERF_COUNT_HW_CACHE_REFERENCES] = { 0x04, CNTR_ALL }, /* PAPI_L1_ICA */
        [PERF_COUNT_HW_CACHE_MISSES] = { 0x07, CNTR_ALL }, /* PAPI_L1_ICM */
        [PERF_COUNT_HW_BRANCH_INSTRUCTIONS] = { 0x1b, CNTR_ALL }, /* PAPI_BR_CN */
        [PERF_COUNT_HW_BRANCH_MISSES] = { 0x1c, CNTR_ALL }, /* PAPI_BR_MSP */
};

/* 24K/34K/1004K/interAptiv/loongson1 cores share the same cache event map. */
static const struct mips_perf_event mipsxxcore_cache_map
                                [PERF_COUNT_HW_CACHE_MAX]
                                [PERF_COUNT_HW_CACHE_OP_MAX]
                                [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
[C(L1D)] = {
        /*
         * Like some other architectures (e.g. ARM), the performance
         * counters don't differentiate between read and write
         * accesses/misses, so this isn't strictly correct, but it's the
         * best we can do. Writes and reads get combined.
         */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x0a, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x0b, CNTR_EVEN | CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x0a, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x0b, CNTR_EVEN | CNTR_ODD, T },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x09, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x09, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x09, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x09, CNTR_ODD, T },
        },
        [C(OP_PREFETCH)] = {
                [C(RESULT_ACCESS)]      = { 0x14, CNTR_EVEN, T },
                /*
                 * Note that MIPS has only "hit" events countable for
                 * the prefetch operation.
                 */
        },
},
[C(LL)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x15, CNTR_ODD, P },
                [C(RESULT_MISS)]        = { 0x16, CNTR_EVEN, P },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x15, CNTR_ODD, P },
                [C(RESULT_MISS)]        = { 0x16, CNTR_EVEN, P },
        },
},
[C(DTLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x06, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x06, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x06, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x06, CNTR_ODD, T },
        },
},
[C(ITLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x05, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x05, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x05, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x05, CNTR_ODD, T },
        },
},
[C(BPU)] = {
        /* Using the same code for *HW_BRANCH* */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x02, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x02, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD, T },
        },
},
};

/* 74K/proAptiv core has completely different cache event map. */
static const struct mips_perf_event mipsxxcore_cache_map2
                                [PERF_COUNT_HW_CACHE_MAX]
                                [PERF_COUNT_HW_CACHE_OP_MAX]
                                [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
[C(L1D)] = {
        /*
         * Like some other architectures (e.g. ARM), the performance
         * counters don't differentiate between read and write
         * accesses/misses, so this isn't strictly correct, but it's the
         * best we can do. Writes and reads get combined.
         */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x17, CNTR_ODD, T },
                [C(RESULT_MISS)]        = { 0x18, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x17, CNTR_ODD, T },
                [C(RESULT_MISS)]        = { 0x18, CNTR_ODD, T },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x06, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x06, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x06, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x06, CNTR_ODD, T },
        },
        [C(OP_PREFETCH)] = {
                [C(RESULT_ACCESS)]      = { 0x34, CNTR_EVEN, T },
                /*
                 * Note that MIPS has only "hit" events countable for
                 * the prefetch operation.
                 */

        },
},
[C(LL)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x1c, CNTR_ODD, P },
                [C(RESULT_MISS)]        = { 0x1d, CNTR_EVEN, P },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x1c, CNTR_ODD, P },
                [C(RESULT_MISS)]        = { 0x1d, CNTR_EVEN, P },
        },
},
/*
 * 74K core does not have specific DTLB events. proAptiv core has
 * "speculative" DTLB events which are numbered 0x63 (even/odd) and
 * not included here. One can use raw events if really needed.
 */
[C(ITLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x04, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x04, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x04, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x04, CNTR_ODD, T },
        },
},
[C(BPU)] = {
        /* Using the same code for *HW_BRANCH* */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x27, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x27, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x27, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 0x27, CNTR_ODD, T },
        },
},
};

static const struct mips_perf_event i6x00_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)]      = { 0x46, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x49, CNTR_EVEN | CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x47, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x4a, CNTR_EVEN | CNTR_ODD },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x84, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x85, CNTR_EVEN | CNTR_ODD },
        },
},
[C(DTLB)] = {
        /* Can't distinguish read & write */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x40, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x41, CNTR_EVEN | CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x40, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x41, CNTR_EVEN | CNTR_ODD },
        },
},
[C(BPU)] = {
        /* Conditional branches / mispredicted */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x15, CNTR_EVEN | CNTR_ODD },
                [C(RESULT_MISS)]        = { 0x16, CNTR_EVEN | CNTR_ODD },
        },
},
};

static const struct mips_perf_event loongson3_cache_map
                                [PERF_COUNT_HW_CACHE_MAX]
                                [PERF_COUNT_HW_CACHE_OP_MAX]
                                [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
[C(L1D)] = {
        /*
         * Like some other architectures (e.g. ARM), the performance
         * counters don't differentiate between read and write
         * accesses/misses, so this isn't strictly correct, but it's the
         * best we can do. Writes and reads get combined.
         */
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x04, CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x04, CNTR_ODD },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x04, CNTR_EVEN },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x04, CNTR_EVEN },
        },
},
[C(DTLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x09, CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x09, CNTR_ODD },
        },
},
[C(ITLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x0c, CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x0c, CNTR_ODD },
        },
},
[C(BPU)] = {
        /* Using the same code for *HW_BRANCH* */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x02, CNTR_EVEN },
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x02, CNTR_EVEN },
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD },
        },
},
};

/* BMIPS5000 */
static const struct mips_perf_event bmips5000_cache_map
                                [PERF_COUNT_HW_CACHE_MAX]
                                [PERF_COUNT_HW_CACHE_OP_MAX]
                                [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
[C(L1D)] = {
        /*
         * Like some other architectures (e.g. ARM), the performance
         * counters don't differentiate between read and write
         * accesses/misses, so this isn't strictly correct, but it's the
         * best we can do. Writes and reads get combined.
         */
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 12, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 12, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 12, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 12, CNTR_ODD, T },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 10, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 10, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 10, CNTR_EVEN, T },
                [C(RESULT_MISS)]        = { 10, CNTR_ODD, T },
        },
        [C(OP_PREFETCH)] = {
                [C(RESULT_ACCESS)]      = { 23, CNTR_EVEN, T },
                /*
                 * Note that MIPS has only "hit" events countable for
                 * the prefetch operation.
                 */
        },
},
[C(LL)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 28, CNTR_EVEN, P },
                [C(RESULT_MISS)]        = { 28, CNTR_ODD, P },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 28, CNTR_EVEN, P },
                [C(RESULT_MISS)]        = { 28, CNTR_ODD, P },
        },
},
[C(BPU)] = {
        /* Using the same code for *HW_BRANCH* */
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD, T },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x02, CNTR_ODD, T },
        },
},
};


static const struct mips_perf_event octeon_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)]      = { 0x2b, CNTR_ALL },
                [C(RESULT_MISS)]        = { 0x2e, CNTR_ALL },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x30, CNTR_ALL },
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x18, CNTR_ALL },
        },
        [C(OP_PREFETCH)] = {
                [C(RESULT_ACCESS)]      = { 0x19, CNTR_ALL },
        },
},
[C(DTLB)] = {
        /*
         * Only general DTLB misses are counted use the same event for
         * read and write.
         */
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x35, CNTR_ALL },
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x35, CNTR_ALL },
        },
},
[C(ITLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x37, CNTR_ALL },
        },
},
};

static const struct mips_perf_event xlp_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)]      = { 0x31, CNTR_ALL }, /* PAPI_L1_DCR */
                [C(RESULT_MISS)]        = { 0x30, CNTR_ALL }, /* PAPI_L1_LDM */
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x2f, CNTR_ALL }, /* PAPI_L1_DCW */
                [C(RESULT_MISS)]        = { 0x2e, CNTR_ALL }, /* PAPI_L1_STM */
        },
},
[C(L1I)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x04, CNTR_ALL }, /* PAPI_L1_ICA */
                [C(RESULT_MISS)]        = { 0x07, CNTR_ALL }, /* PAPI_L1_ICM */
        },
},
[C(LL)] = {
        [C(OP_READ)] = {
                [C(RESULT_ACCESS)]      = { 0x35, CNTR_ALL }, /* PAPI_L2_DCR */
                [C(RESULT_MISS)]        = { 0x37, CNTR_ALL }, /* PAPI_L2_LDM */
        },
        [C(OP_WRITE)] = {
                [C(RESULT_ACCESS)]      = { 0x34, CNTR_ALL }, /* PAPI_L2_DCA */
                [C(RESULT_MISS)]        = { 0x36, CNTR_ALL }, /* PAPI_L2_DCM */
        },
},
[C(DTLB)] = {
        /*
         * Only general DTLB misses are counted use the same event for
         * read and write.
         */
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x2d, CNTR_ALL }, /* PAPI_TLB_DM */
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x2d, CNTR_ALL }, /* PAPI_TLB_DM */
        },
},
[C(ITLB)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x08, CNTR_ALL }, /* PAPI_TLB_IM */
        },
        [C(OP_WRITE)] = {
                [C(RESULT_MISS)]        = { 0x08, CNTR_ALL }, /* PAPI_TLB_IM */
        },
},
[C(BPU)] = {
        [C(OP_READ)] = {
                [C(RESULT_MISS)]        = { 0x25, CNTR_ALL },
        },
},
};

static int __hw_perf_event_init(struct perf_event *event)
{
        struct perf_event_attr *attr = &event->attr;
        struct hw_perf_event *hwc = &event->hw;
        const struct mips_perf_event *pev;
        int err;

        /* Returning MIPS event descriptor for generic perf event. */
        if (PERF_TYPE_HARDWARE == event->attr.type) {
                if (event->attr.config >= PERF_COUNT_HW_MAX)
                        return -EINVAL;
                pev = mipspmu_map_general_event(event->attr.config);
        } else if (PERF_TYPE_HW_CACHE == event->attr.type) {
                pev = mipspmu_map_cache_event(event->attr.config);
        } else if (PERF_TYPE_RAW == event->attr.type) {
                /* We are working on the global raw event. */
                mutex_lock(&raw_event_mutex);
                pev = mipspmu.map_raw_event(event->attr.config);
        } else {
                /* The event type is not (yet) supported. */
                return -EOPNOTSUPP;
        }

        if (IS_ERR(pev)) {
                if (PERF_TYPE_RAW == event->attr.type)
                        mutex_unlock(&raw_event_mutex);
                return PTR_ERR(pev);
        }

        /*
         * We allow max flexibility on how each individual counter shared
         * by the single CPU operates (the mode exclusion and the range).
         */
        hwc->config_base = MIPS_PERFCTRL_IE;

        hwc->event_base = mipspmu_perf_event_encode(pev);
        if (PERF_TYPE_RAW == event->attr.type)
                mutex_unlock(&raw_event_mutex);

        if (!attr->exclude_user)
                hwc->config_base |= MIPS_PERFCTRL_U;
        if (!attr->exclude_kernel) {
                hwc->config_base |= MIPS_PERFCTRL_K;
                /* MIPS kernel mode: KSU == 00b || EXL == 1 || ERL == 1 */
                hwc->config_base |= MIPS_PERFCTRL_EXL;
        }
        if (!attr->exclude_hv)
                hwc->config_base |= MIPS_PERFCTRL_S;

        hwc->config_base &= M_PERFCTL_CONFIG_MASK;
        /*
         * The event can belong to another cpu. We do not assign a local
         * counter for it for now.
         */
        hwc->idx = -1;
        hwc->config = 0;

        if (!hwc->sample_period) {
                hwc->sample_period  = mipspmu.max_period;
                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);

        event->destroy = hw_perf_event_destroy;

        if (err)
                event->destroy(event);

        return err;
}

static void pause_local_counters(void)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        int ctr = mipspmu.num_counters;
        unsigned long flags;

        local_irq_save(flags);
        do {
                ctr--;
                cpuc->saved_ctrl[ctr] = mipsxx_pmu_read_control(ctr);
                mipsxx_pmu_write_control(ctr, cpuc->saved_ctrl[ctr] &
                                         ~M_PERFCTL_COUNT_EVENT_WHENEVER);
        } while (ctr > 0);
        local_irq_restore(flags);
}

static void resume_local_counters(void)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        int ctr = mipspmu.num_counters;

        do {
                ctr--;
                mipsxx_pmu_write_control(ctr, cpuc->saved_ctrl[ctr]);
        } while (ctr > 0);
}

static int mipsxx_pmu_handle_shared_irq(void)
{
        struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
        struct perf_sample_data data;
        unsigned int counters = mipspmu.num_counters;
        u64 counter;
        int handled = IRQ_NONE;
        struct pt_regs *regs;

        if (cpu_has_perf_cntr_intr_bit && !(read_c0_cause() & CAUSEF_PCI))
                return handled;
        /*
         * First we pause the local counters, so that when we are locked
         * here, the counters are all paused. When it gets locked due to
         * perf_disable(), the timer interrupt handler will be delayed.
         *
         * See also mipsxx_pmu_start().
         */
        pause_local_counters();
#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
        read_lock(&pmuint_rwlock);
#endif

        regs = get_irq_regs();

        perf_sample_data_init(&data, 0, 0);

        switch (counters) {
#define HANDLE_COUNTER(n)                                               \
        case n + 1:                                                     \
                if (test_bit(n, cpuc->used_mask)) {                     \
                        counter = mipspmu.read_counter(n);              \
                        if (counter & mipspmu.overflow) {               \
                                handle_associated_event(cpuc, n, &data, regs); \
                                handled = IRQ_HANDLED;                  \
                        }                                               \
                }
        HANDLE_COUNTER(3)
        HANDLE_COUNTER(2)
        HANDLE_COUNTER(1)
        HANDLE_COUNTER(0)
        }

#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
        read_unlock(&pmuint_rwlock);
#endif
        resume_local_counters();

        /*
         * Do all the work for the pending perf events. We can do this
         * in here because the performance counter interrupt is a regular
         * interrupt, not NMI.
         */
        if (handled == IRQ_HANDLED)
                irq_work_run();

        return handled;
}

static irqreturn_t mipsxx_pmu_handle_irq(int irq, void *dev)
{
        return mipsxx_pmu_handle_shared_irq();
}

/* 24K */
#define IS_BOTH_COUNTERS_24K_EVENT(b)                                   \
        ((b) == 0 || (b) == 1 || (b) == 11)

/* 34K */
#define IS_BOTH_COUNTERS_34K_EVENT(b)                                   \
        ((b) == 0 || (b) == 1 || (b) == 11)
#ifdef CONFIG_MIPS_MT_SMP
#define IS_RANGE_P_34K_EVENT(r, b)                                      \
        ((b) == 0 || (r) == 18 || (b) == 21 || (b) == 22 ||             \
         (b) == 25 || (b) == 39 || (r) == 44 || (r) == 174 ||           \
         (r) == 176 || ((b) >= 50 && (b) <= 55) ||                      \
         ((b) >= 64 && (b) <= 67))
#define IS_RANGE_V_34K_EVENT(r) ((r) == 47)
#endif

/* 74K */
#define IS_BOTH_COUNTERS_74K_EVENT(b)                                   \
        ((b) == 0 || (b) == 1)

/* proAptiv */
#define IS_BOTH_COUNTERS_PROAPTIV_EVENT(b)                              \
        ((b) == 0 || (b) == 1)
/* P5600 */
#define IS_BOTH_COUNTERS_P5600_EVENT(b)                                 \
        ((b) == 0 || (b) == 1)

/* 1004K */
#define IS_BOTH_COUNTERS_1004K_EVENT(b)                                 \
        ((b) == 0 || (b) == 1 || (b) == 11)
#ifdef CONFIG_MIPS_MT_SMP
#define IS_RANGE_P_1004K_EVENT(r, b)                                    \
        ((b) == 0 || (r) == 18 || (b) == 21 || (b) == 22 ||             \
         (b) == 25 || (b) == 36 || (b) == 39 || (r) == 44 ||            \
         (r) == 174 || (r) == 176 || ((b) >= 50 && (b) <= 59) ||        \
         (r) == 188 || (b) == 61 || (b) == 62 ||                        \
         ((b) >= 64 && (b) <= 67))
#define IS_RANGE_V_1004K_EVENT(r)       ((r) == 47)
#endif

/* interAptiv */
#define IS_BOTH_COUNTERS_INTERAPTIV_EVENT(b)                            \
        ((b) == 0 || (b) == 1 || (b) == 11)
#ifdef CONFIG_MIPS_MT_SMP
/* The P/V/T info is not provided for "(b) == 38" in SUM, assume P. */
#define IS_RANGE_P_INTERAPTIV_EVENT(r, b)                               \
        ((b) == 0 || (r) == 18 || (b) == 21 || (b) == 22 ||             \
         (b) == 25 || (b) == 36 || (b) == 38 || (b) == 39 ||            \
         (r) == 44 || (r) == 174 || (r) == 176 || ((b) >= 50 &&         \
         (b) <= 59) || (r) == 188 || (b) == 61 || (b) == 62 ||          \
         ((b) >= 64 && (b) <= 67))
#define IS_RANGE_V_INTERAPTIV_EVENT(r)  ((r) == 47 || (r) == 175)
#endif

/* BMIPS5000 */
#define IS_BOTH_COUNTERS_BMIPS5000_EVENT(b)                             \
        ((b) == 0 || (b) == 1)


/*
 * For most cores the user can use 0-255 raw events, where 0-127 for the events
 * of even counters, and 128-255 for odd counters. Note that bit 7 is used to
 * indicate the even/odd bank selector. So, for example, when user wants to take
 * the Event Num of 15 for odd counters (by referring to the user manual), then
 * 128 needs to be added to 15 as the input for the event config, i.e., 143 (0x8F)
 * to be used.
 *
 * Some newer cores have even more events, in which case the user can use raw
 * events 0-511, where 0-255 are for the events of even counters, and 256-511
 * are for odd counters, so bit 8 is used to indicate the even/odd bank selector.
 */
static const struct mips_perf_event *mipsxx_pmu_map_raw_event(u64 config)
{
        /* currently most cores have 7-bit event numbers */
        unsigned int raw_id = config & 0xff;
        unsigned int base_id = raw_id & 0x7f;

        switch (current_cpu_type()) {
        case CPU_24K:
                if (IS_BOTH_COUNTERS_24K_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                /*
                 * This is actually doing nothing. Non-multithreading
                 * CPUs will not check and calculate the range.
                 */
                raw_event.range = P;
#endif
                break;
        case CPU_34K:
                if (IS_BOTH_COUNTERS_34K_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                if (IS_RANGE_P_34K_EVENT(raw_id, base_id))
                        raw_event.range = P;
                else if (unlikely(IS_RANGE_V_34K_EVENT(raw_id)))
                        raw_event.range = V;
                else
                        raw_event.range = T;
#endif
                break;
        case CPU_74K:
        case CPU_1074K:
                if (IS_BOTH_COUNTERS_74K_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                raw_event.range = P;
#endif
                break;
        case CPU_PROAPTIV:
                if (IS_BOTH_COUNTERS_PROAPTIV_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                raw_event.range = P;
#endif
                break;
        case CPU_P5600:
        case CPU_P6600:
                /* 8-bit event numbers */
                raw_id = config & 0x1ff;
                base_id = raw_id & 0xff;
                if (IS_BOTH_COUNTERS_P5600_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 255 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                raw_event.range = P;
#endif
                break;
        case CPU_I6400:
        case CPU_I6500:
                /* 8-bit event numbers */
                base_id = config & 0xff;
                raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                break;
        case CPU_1004K:
                if (IS_BOTH_COUNTERS_1004K_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                if (IS_RANGE_P_1004K_EVENT(raw_id, base_id))
                        raw_event.range = P;
                else if (unlikely(IS_RANGE_V_1004K_EVENT(raw_id)))
                        raw_event.range = V;
                else
                        raw_event.range = T;
#endif
                break;
        case CPU_INTERAPTIV:
                if (IS_BOTH_COUNTERS_INTERAPTIV_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
#ifdef CONFIG_MIPS_MT_SMP
                if (IS_RANGE_P_INTERAPTIV_EVENT(raw_id, base_id))
                        raw_event.range = P;
                else if (unlikely(IS_RANGE_V_INTERAPTIV_EVENT(raw_id)))
                        raw_event.range = V;
                else
                        raw_event.range = T;
#endif
                break;
        case CPU_BMIPS5000:
                if (IS_BOTH_COUNTERS_BMIPS5000_EVENT(base_id))
                        raw_event.cntr_mask = CNTR_EVEN | CNTR_ODD;
                else
                        raw_event.cntr_mask =
                                raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
                break;
        case CPU_LOONGSON3:
                raw_event.cntr_mask = raw_id > 127 ? CNTR_ODD : CNTR_EVEN;
        break;
        }

        raw_event.event_id = base_id;

        return &raw_event;
}

static const struct mips_perf_event *octeon_pmu_map_raw_event(u64 config)
{
        unsigned int raw_id = config & 0xff;
        unsigned int base_id = raw_id & 0x7f;


        raw_event.cntr_mask = CNTR_ALL;
        raw_event.event_id = base_id;

        if (current_cpu_type() == CPU_CAVIUM_OCTEON2) {
                if (base_id > 0x42)
                        return ERR_PTR(-EOPNOTSUPP);
        } else {
                if (base_id > 0x3a)
                        return ERR_PTR(-EOPNOTSUPP);
        }

        switch (base_id) {
        case 0x00:
        case 0x0f:
        case 0x1e:
        case 0x1f:
        case 0x2f:
        case 0x34:
        case 0x3b ... 0x3f:
                return ERR_PTR(-EOPNOTSUPP);
        default:
                break;
        }

        return &raw_event;
}

static const struct mips_perf_event *xlp_pmu_map_raw_event(u64 config)
{
        unsigned int raw_id = config & 0xff;

        /* Only 1-63 are defined */
        if ((raw_id < 0x01) || (raw_id > 0x3f))
                return ERR_PTR(-EOPNOTSUPP);

        raw_event.cntr_mask = CNTR_ALL;
        raw_event.event_id = raw_id;

        return &raw_event;
}

static int __init
init_hw_perf_events(void)
{
        int counters, irq;
        int counter_bits;

        pr_info("Performance counters: ");

        counters = n_counters();
        if (counters == 0) {
                pr_cont("No available PMU.\n");
                return -ENODEV;
        }

#ifdef CONFIG_MIPS_PERF_SHARED_TC_COUNTERS
        if (!cpu_has_mipsmt_pertccounters)
                counters = counters_total_to_per_cpu(counters);
#endif

        if (get_c0_perfcount_int)
                irq = get_c0_perfcount_int();
        else if (cp0_perfcount_irq >= 0)
                irq = MIPS_CPU_IRQ_BASE + cp0_perfcount_irq;
        else
                irq = -1;

        mipspmu.map_raw_event = mipsxx_pmu_map_raw_event;

        switch (current_cpu_type()) {
        case CPU_24K:
                mipspmu.name = "mips/24K";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_34K:
                mipspmu.name = "mips/34K";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_74K:
                mipspmu.name = "mips/74K";
                mipspmu.general_event_map = &mipsxxcore_event_map2;
                mipspmu.cache_event_map = &mipsxxcore_cache_map2;
                break;
        case CPU_PROAPTIV:
                mipspmu.name = "mips/proAptiv";
                mipspmu.general_event_map = &mipsxxcore_event_map2;
                mipspmu.cache_event_map = &mipsxxcore_cache_map2;
                break;
        case CPU_P5600:
                mipspmu.name = "mips/P5600";
                mipspmu.general_event_map = &mipsxxcore_event_map2;
                mipspmu.cache_event_map = &mipsxxcore_cache_map2;
                break;
        case CPU_P6600:
                mipspmu.name = "mips/P6600";
                mipspmu.general_event_map = &mipsxxcore_event_map2;
                mipspmu.cache_event_map = &mipsxxcore_cache_map2;
                break;
        case CPU_I6400:
                mipspmu.name = "mips/I6400";
                mipspmu.general_event_map = &i6x00_event_map;
                mipspmu.cache_event_map = &i6x00_cache_map;
                break;
        case CPU_I6500:
                mipspmu.name = "mips/I6500";
                mipspmu.general_event_map = &i6x00_event_map;
                mipspmu.cache_event_map = &i6x00_cache_map;
                break;
        case CPU_1004K:
                mipspmu.name = "mips/1004K";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_1074K:
                mipspmu.name = "mips/1074K";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_INTERAPTIV:
                mipspmu.name = "mips/interAptiv";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_LOONGSON1:
                mipspmu.name = "mips/loongson1";
                mipspmu.general_event_map = &mipsxxcore_event_map;
                mipspmu.cache_event_map = &mipsxxcore_cache_map;
                break;
        case CPU_LOONGSON3:
                mipspmu.name = "mips/loongson3";
                mipspmu.general_event_map = &loongson3_event_map;
                mipspmu.cache_event_map = &loongson3_cache_map;
                break;
        case CPU_CAVIUM_OCTEON:
        case CPU_CAVIUM_OCTEON_PLUS:
        case CPU_CAVIUM_OCTEON2:
                mipspmu.name = "octeon";
                mipspmu.general_event_map = &octeon_event_map;
                mipspmu.cache_event_map = &octeon_cache_map;
                mipspmu.map_raw_event = octeon_pmu_map_raw_event;
                break;
        case CPU_BMIPS5000:
                mipspmu.name = "BMIPS5000";
                mipspmu.general_event_map = &bmips5000_event_map;
                mipspmu.cache_event_map = &bmips5000_cache_map;
                break;
        case CPU_XLP:
                mipspmu.name = "xlp";
                mipspmu.general_event_map = &xlp_event_map;
                mipspmu.cache_event_map = &xlp_cache_map;
                mipspmu.map_raw_event = xlp_pmu_map_raw_event;
                break;
        default:
                pr_cont("Either hardware does not support performance "
                        "counters, or not yet implemented.\n");
                return -ENODEV;
        }

        mipspmu.num_counters = counters;
        mipspmu.irq = irq;

        if (read_c0_perfctrl0() & MIPS_PERFCTRL_W) {
                mipspmu.max_period = (1ULL << 63) - 1;
                mipspmu.valid_count = (1ULL << 63) - 1;
                mipspmu.overflow = 1ULL << 63;
                mipspmu.read_counter = mipsxx_pmu_read_counter_64;
                mipspmu.write_counter = mipsxx_pmu_write_counter_64;
                counter_bits = 64;
        } else {
                mipspmu.max_period = (1ULL << 31) - 1;
                mipspmu.valid_count = (1ULL << 31) - 1;
                mipspmu.overflow = 1ULL << 31;
                mipspmu.read_counter = mipsxx_pmu_read_counter;
                mipspmu.write_counter = mipsxx_pmu_write_counter;
                counter_bits = 32;
        }

        on_each_cpu(reset_counters, (void *)(long)counters, 1);

        pr_cont("%s PMU enabled, %d %d-bit counters available to each "
                "CPU, irq %d%s\n", mipspmu.name, counters, counter_bits, irq,
                irq < 0 ? " (share with timer interrupt)" : "");

        perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);

        return 0;
}
early_initcall(init_hw_perf_events);