#include <linux/perf_event.h>
#include <linux/export.h>
#include <linux/types.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <asm/apicdef.h>

#include "../perf_event.h"

static __initconst const u64 amd_hw_cache_event_ids
                                [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) ] = 0x0040, /* Data Cache Accesses        */
                [ C(RESULT_MISS)   ] = 0x0141, /* Data Cache Misses          */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = 0,
                [ C(RESULT_MISS)   ] = 0,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = 0x0267, /* Data Prefetcher :attempts  */
                [ C(RESULT_MISS)   ] = 0x0167, /* Data Prefetcher :cancelled */
        },
 },
 [ C(L1I ) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction cache fetches  */
                [ C(RESULT_MISS)   ] = 0x0081, /* Instruction cache misses   */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = 0x014B, /* Prefetch Instructions :Load */
                [ C(RESULT_MISS)   ] = 0,
        },
 },
 [ C(LL  ) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0x037D, /* Requests to L2 Cache :IC+DC */
                [ C(RESULT_MISS)   ] = 0x037E, /* L2 Cache Misses : IC+DC     */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = 0x017F, /* L2 Fill/Writeback           */
                [ C(RESULT_MISS)   ] = 0,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = 0,
                [ C(RESULT_MISS)   ] = 0,
        },
 },
 [ C(DTLB) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
                [ C(RESULT_MISS)   ] = 0x0746, /* L1_DTLB_AND_L2_DLTB_MISS.ALL */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = 0,
                [ C(RESULT_MISS)   ] = 0,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = 0,
                [ C(RESULT_MISS)   ] = 0,
        },
 },
 [ C(ITLB) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0x0080, /* Instruction fecthes        */
                [ C(RESULT_MISS)   ] = 0x0385, /* L1_ITLB_AND_L2_ITLB_MISS.ALL */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
 },
 [ C(BPU ) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0x00c2, /* Retired Branch Instr.      */
                [ C(RESULT_MISS)   ] = 0x00c3, /* Retired Mispredicted BI    */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
 },
 [ C(NODE) ] = {
        [ C(OP_READ) ] = {
                [ C(RESULT_ACCESS) ] = 0xb8e9, /* CPU Request to Memory, l+r */
                [ C(RESULT_MISS)   ] = 0x98e9, /* CPU Request to Memory, r   */
        },
        [ C(OP_WRITE) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
        [ C(OP_PREFETCH) ] = {
                [ C(RESULT_ACCESS) ] = -1,
                [ C(RESULT_MISS)   ] = -1,
        },
 },
};

/*
 * AMD Performance Monitor K7 and later.
 */
static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
{
  [PERF_COUNT_HW_CPU_CYCLES]                    = 0x0076,
  [PERF_COUNT_HW_INSTRUCTIONS]                  = 0x00c0,
  [PERF_COUNT_HW_CACHE_REFERENCES]              = 0x077d,
  [PERF_COUNT_HW_CACHE_MISSES]                  = 0x077e,
  [PERF_COUNT_HW_BRANCH_INSTRUCTIONS]           = 0x00c2,
  [PERF_COUNT_HW_BRANCH_MISSES]                 = 0x00c3,
  [PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]       = 0x00d0, /* "Decoder empty" event */
  [PERF_COUNT_HW_STALLED_CYCLES_BACKEND]        = 0x00d1, /* "Dispatch stalls" event */
};

static u64 amd_pmu_event_map(int hw_event)
{
        return amd_perfmon_event_map[hw_event];
}

/*
 * Previously calculated offsets
 */
static unsigned int event_offsets[X86_PMC_IDX_MAX] __read_mostly;
static unsigned int count_offsets[X86_PMC_IDX_MAX] __read_mostly;

/*
 * Legacy CPUs:
 *   4 counters starting at 0xc0010000 each offset by 1
 *
 * CPUs with core performance counter extensions:
 *   6 counters starting at 0xc0010200 each offset by 2
 */
static inline int amd_pmu_addr_offset(int index, bool eventsel)
{
        int offset;

        if (!index)
                return index;

        if (eventsel)
                offset = event_offsets[index];
        else
                offset = count_offsets[index];

        if (offset)
                return offset;

        if (!cpu_has_perfctr_core)
                offset = index;
        else
                offset = index << 1;

        if (eventsel)
                event_offsets[index] = offset;
        else
                count_offsets[index] = offset;

        return offset;
}

static int amd_core_hw_config(struct perf_event *event)
{
        if (event->attr.exclude_host && event->attr.exclude_guest)
                /*
                 * When HO == GO == 1 the hardware treats that as GO == HO == 0
                 * and will count in both modes. We don't want to count in that
                 * case so we emulate no-counting by setting US = OS = 0.
                 */
                event->hw.config &= ~(ARCH_PERFMON_EVENTSEL_USR |
                                      ARCH_PERFMON_EVENTSEL_OS);
        else if (event->attr.exclude_host)
                event->hw.config |= AMD64_EVENTSEL_GUESTONLY;
        else if (event->attr.exclude_guest)
                event->hw.config |= AMD64_EVENTSEL_HOSTONLY;

        return 0;
}

/*
 * AMD64 events are detected based on their event codes.
 */
static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
{
        return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
}

static inline int amd_is_nb_event(struct hw_perf_event *hwc)
{
        return (hwc->config & 0xe0) == 0xe0;
}

static inline int amd_has_nb(struct cpu_hw_events *cpuc)
{
        struct amd_nb *nb = cpuc->amd_nb;

        return nb && nb->nb_id != -1;
}

static int amd_pmu_hw_config(struct perf_event *event)
{
        int ret;

        /* pass precise event sampling to ibs: */
        if (event->attr.precise_ip && get_ibs_caps())
                return -ENOENT;

        if (has_branch_stack(event))
                return -EOPNOTSUPP;

        ret = x86_pmu_hw_config(event);
        if (ret)
                return ret;

        if (event->attr.type == PERF_TYPE_RAW)
                event->hw.config |= event->attr.config & AMD64_RAW_EVENT_MASK;

        return amd_core_hw_config(event);
}

static void __amd_put_nb_event_constraints(struct cpu_hw_events *cpuc,
                                           struct perf_event *event)
{
        struct amd_nb *nb = cpuc->amd_nb;
        int i;

        /*
         * need to scan whole list because event may not have
         * been assigned during scheduling
         *
         * no race condition possible because event can only
         * be removed on one CPU at a time AND PMU is disabled
         * when we come here
         */
        for (i = 0; i < x86_pmu.num_counters; i++) {
                if (cmpxchg(nb->owners + i, event, NULL) == event)
                        break;
        }
}

 /*
  * AMD64 NorthBridge events need special treatment because
  * counter access needs to be synchronized across all cores
  * of a package. Refer to BKDG section 3.12
  *
  * NB events are events measuring L3 cache, Hypertransport
  * traffic. They are identified by an event code >= 0xe00.
  * They measure events on the NorthBride which is shared
  * by all cores on a package. NB events are counted on a
  * shared set of counters. When a NB event is programmed
  * in a counter, the data actually comes from a shared
  * counter. Thus, access to those counters needs to be
  * synchronized.
  *
  * We implement the synchronization such that no two cores
  * can be measuring NB events using the same counters. Thus,
  * we maintain a per-NB allocation table. The available slot
  * is propagated using the event_constraint structure.
  *
  * We provide only one choice for each NB event based on
  * the fact that only NB events have restrictions. Consequently,
  * if a counter is available, there is a guarantee the NB event
  * will be assigned to it. If no slot is available, an empty
  * constraint is returned and scheduling will eventually fail
  * for this event.
  *
  * Note that all cores attached the same NB compete for the same
  * counters to host NB events, this is why we use atomic ops. Some
  * multi-chip CPUs may have more than one NB.
  *
  * Given that resources are allocated (cmpxchg), they must be
  * eventually freed for others to use. This is accomplished by
  * calling __amd_put_nb_event_constraints()
  *
  * Non NB events are not impacted by this restriction.
  */
static struct event_constraint *
__amd_get_nb_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
                               struct event_constraint *c)
{
        struct hw_perf_event *hwc = &event->hw;
        struct amd_nb *nb = cpuc->amd_nb;
        struct perf_event *old;
        int idx, new = -1;

        if (!c)
                c = &unconstrained;

        if (cpuc->is_fake)
                return c;

        /*
         * detect if already present, if so reuse
         *
         * cannot merge with actual allocation
         * because of possible holes
         *
         * event can already be present yet not assigned (in hwc->idx)
         * because of successive calls to x86_schedule_events() from
         * hw_perf_group_sched_in() without hw_perf_enable()
         */
        for_each_set_bit(idx, c->idxmsk, x86_pmu.num_counters) {
                if (new == -1 || hwc->idx == idx)
                        /* assign free slot, prefer hwc->idx */
                        old = cmpxchg(nb->owners + idx, NULL, event);
                else if (nb->owners[idx] == event)
                        /* event already present */
                        old = event;
                else
                        continue;

                if (old && old != event)
                        continue;

                /* reassign to this slot */
                if (new != -1)
                        cmpxchg(nb->owners + new, event, NULL);
                new = idx;

                /* already present, reuse */
                if (old == event)
                        break;
        }

        if (new == -1)
                return &emptyconstraint;

        return &nb->event_constraints[new];
}

static struct amd_nb *amd_alloc_nb(int cpu)
{
        struct amd_nb *nb;
        int i;

        nb = kzalloc_node(sizeof(struct amd_nb), GFP_KERNEL, cpu_to_node(cpu));
        if (!nb)
                return NULL;

        nb->nb_id = -1;

        /*
         * initialize all possible NB constraints
         */
        for (i = 0; i < x86_pmu.num_counters; i++) {
                __set_bit(i, nb->event_constraints[i].idxmsk);
                nb->event_constraints[i].weight = 1;
        }
        return nb;
}

static int amd_pmu_cpu_prepare(int cpu)
{
        struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);

        WARN_ON_ONCE(cpuc->amd_nb);

        if (!x86_pmu.amd_nb_constraints)
                return NOTIFY_OK;

        cpuc->amd_nb = amd_alloc_nb(cpu);
        if (!cpuc->amd_nb)
                return NOTIFY_BAD;

        return NOTIFY_OK;
}

static void amd_pmu_cpu_starting(int cpu)
{
        struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
        void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
        struct amd_nb *nb;
        int i, nb_id;

        cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;

        if (!x86_pmu.amd_nb_constraints)
                return;

        nb_id = amd_get_nb_id(cpu);
        WARN_ON_ONCE(nb_id == BAD_APICID);

        for_each_online_cpu(i) {
                nb = per_cpu(cpu_hw_events, i).amd_nb;
                if (WARN_ON_ONCE(!nb))
                        continue;

                if (nb->nb_id == nb_id) {
                        *onln = cpuc->amd_nb;
                        cpuc->amd_nb = nb;
                        break;
                }
        }

        cpuc->amd_nb->nb_id = nb_id;
        cpuc->amd_nb->refcnt++;
}

static void amd_pmu_cpu_dead(int cpu)
{
        struct cpu_hw_events *cpuhw;

        if (!x86_pmu.amd_nb_constraints)
                return;

        cpuhw = &per_cpu(cpu_hw_events, cpu);

        if (cpuhw->amd_nb) {
                struct amd_nb *nb = cpuhw->amd_nb;

                if (nb->nb_id == -1 || --nb->refcnt == 0)
                        kfree(nb);

                cpuhw->amd_nb = NULL;
        }
}

static struct event_constraint *
amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
                          struct perf_event *event)
{
        /*
         * if not NB event or no NB, then no constraints
         */
        if (!(amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)))
                return &unconstrained;

        return __amd_get_nb_event_constraints(cpuc, event, NULL);
}

static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
                                      struct perf_event *event)
{
        if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
                __amd_put_nb_event_constraints(cpuc, event);
}

PMU_FORMAT_ATTR(event,  "config:0-7,32-35");
PMU_FORMAT_ATTR(umask,  "config:8-15"   );
PMU_FORMAT_ATTR(edge,   "config:18"     );
PMU_FORMAT_ATTR(inv,    "config:23"     );
PMU_FORMAT_ATTR(cmask,  "config:24-31"  );

static struct attribute *amd_format_attr[] = {
        &format_attr_event.attr,
        &format_attr_umask.attr,
        &format_attr_edge.attr,
        &format_attr_inv.attr,
        &format_attr_cmask.attr,
        NULL,
};

/* AMD Family 15h */

#define AMD_EVENT_TYPE_MASK     0x000000F0ULL

#define AMD_EVENT_FP            0x00000000ULL ... 0x00000010ULL
#define AMD_EVENT_LS            0x00000020ULL ... 0x00000030ULL
#define AMD_EVENT_DC            0x00000040ULL ... 0x00000050ULL
#define AMD_EVENT_CU            0x00000060ULL ... 0x00000070ULL
#define AMD_EVENT_IC_DE         0x00000080ULL ... 0x00000090ULL
#define AMD_EVENT_EX_LS         0x000000C0ULL
#define AMD_EVENT_DE            0x000000D0ULL
#define AMD_EVENT_NB            0x000000E0ULL ... 0x000000F0ULL

/*
 * AMD family 15h event code/PMC mappings:
 *
 * type = event_code & 0x0F0:
 *
 * 0x000        FP      PERF_CTL[5:3]
 * 0x010        FP      PERF_CTL[5:3]
 * 0x020        LS      PERF_CTL[5:0]
 * 0x030        LS      PERF_CTL[5:0]
 * 0x040        DC      PERF_CTL[5:0]
 * 0x050        DC      PERF_CTL[5:0]
 * 0x060        CU      PERF_CTL[2:0]
 * 0x070        CU      PERF_CTL[2:0]
 * 0x080        IC/DE   PERF_CTL[2:0]
 * 0x090        IC/DE   PERF_CTL[2:0]
 * 0x0A0        ---
 * 0x0B0        ---
 * 0x0C0        EX/LS   PERF_CTL[5:0]
 * 0x0D0        DE      PERF_CTL[2:0]
 * 0x0E0        NB      NB_PERF_CTL[3:0]
 * 0x0F0        NB      NB_PERF_CTL[3:0]
 *
 * Exceptions:
 *
 * 0x000        FP      PERF_CTL[3], PERF_CTL[5:3] (*)
 * 0x003        FP      PERF_CTL[3]
 * 0x004        FP      PERF_CTL[3], PERF_CTL[5:3] (*)
 * 0x00B        FP      PERF_CTL[3]
 * 0x00D        FP      PERF_CTL[3]
 * 0x023        DE      PERF_CTL[2:0]
 * 0x02D        LS      PERF_CTL[3]
 * 0x02E        LS      PERF_CTL[3,0]
 * 0x031        LS      PERF_CTL[2:0] (**)
 * 0x043        CU      PERF_CTL[2:0]
 * 0x045        CU      PERF_CTL[2:0]
 * 0x046        CU      PERF_CTL[2:0]
 * 0x054        CU      PERF_CTL[2:0]
 * 0x055        CU      PERF_CTL[2:0]
 * 0x08F        IC      PERF_CTL[0]
 * 0x187        DE      PERF_CTL[0]
 * 0x188        DE      PERF_CTL[0]
 * 0x0DB        EX      PERF_CTL[5:0]
 * 0x0DC        LS      PERF_CTL[5:0]
 * 0x0DD        LS      PERF_CTL[5:0]
 * 0x0DE        LS      PERF_CTL[5:0]
 * 0x0DF        LS      PERF_CTL[5:0]
 * 0x1C0        EX      PERF_CTL[5:3]
 * 0x1D6        EX      PERF_CTL[5:0]
 * 0x1D8        EX      PERF_CTL[5:0]
 *
 * (*)  depending on the umask all FPU counters may be used
 * (**) only one unitmask enabled at a time
 */

static struct event_constraint amd_f15_PMC0  = EVENT_CONSTRAINT(0, 0x01, 0);
static struct event_constraint amd_f15_PMC20 = EVENT_CONSTRAINT(0, 0x07, 0);
static struct event_constraint amd_f15_PMC3  = EVENT_CONSTRAINT(0, 0x08, 0);
static struct event_constraint amd_f15_PMC30 = EVENT_CONSTRAINT_OVERLAP(0, 0x09, 0);
static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);

static struct event_constraint *
amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
                               struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;
        unsigned int event_code = amd_get_event_code(hwc);

        switch (event_code & AMD_EVENT_TYPE_MASK) {
        case AMD_EVENT_FP:
                switch (event_code) {
                case 0x000:
                        if (!(hwc->config & 0x0000F000ULL))
                                break;
                        if (!(hwc->config & 0x00000F00ULL))
                                break;
                        return &amd_f15_PMC3;
                case 0x004:
                        if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
                                break;
                        return &amd_f15_PMC3;
                case 0x003:
                case 0x00B:
                case 0x00D:
                        return &amd_f15_PMC3;
                }
                return &amd_f15_PMC53;
        case AMD_EVENT_LS:
        case AMD_EVENT_DC:
        case AMD_EVENT_EX_LS:
                switch (event_code) {
                case 0x023:
                case 0x043:
                case 0x045:
                case 0x046:
                case 0x054:
                case 0x055:
                        return &amd_f15_PMC20;
                case 0x02D:
                        return &amd_f15_PMC3;
                case 0x02E:
                        return &amd_f15_PMC30;
                case 0x031:
                        if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
                                return &amd_f15_PMC20;
                        return &emptyconstraint;
                case 0x1C0:
                        return &amd_f15_PMC53;
                default:
                        return &amd_f15_PMC50;
                }
        case AMD_EVENT_CU:
        case AMD_EVENT_IC_DE:
        case AMD_EVENT_DE:
                switch (event_code) {
                case 0x08F:
                case 0x187:
                case 0x188:
                        return &amd_f15_PMC0;
                case 0x0DB ... 0x0DF:
                case 0x1D6:
                case 0x1D8:
                        return &amd_f15_PMC50;
                default:
                        return &amd_f15_PMC20;
                }
        case AMD_EVENT_NB:
                /* moved to uncore.c */
                return &emptyconstraint;
        default:
                return &emptyconstraint;
        }
}

static ssize_t amd_event_sysfs_show(char *page, u64 config)
{
        u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) |
                    (config & AMD64_EVENTSEL_EVENT) >> 24;

        return x86_event_sysfs_show(page, config, event);
}

static __initconst const struct x86_pmu amd_pmu = {
        .name                   = "AMD",
        .handle_irq             = x86_pmu_handle_irq,
        .disable_all            = x86_pmu_disable_all,
        .enable_all             = x86_pmu_enable_all,
        .enable                 = x86_pmu_enable_event,
        .disable                = x86_pmu_disable_event,
        .hw_config              = amd_pmu_hw_config,
        .schedule_events        = x86_schedule_events,
        .eventsel               = MSR_K7_EVNTSEL0,
        .perfctr                = MSR_K7_PERFCTR0,
        .addr_offset            = amd_pmu_addr_offset,
        .event_map              = amd_pmu_event_map,
        .max_events             = ARRAY_SIZE(amd_perfmon_event_map),
        .num_counters           = AMD64_NUM_COUNTERS,
        .cntval_bits            = 48,
        .cntval_mask            = (1ULL << 48) - 1,
        .apic                   = 1,
        /* use highest bit to detect overflow */
        .max_period             = (1ULL << 47) - 1,
        .get_event_constraints  = amd_get_event_constraints,
        .put_event_constraints  = amd_put_event_constraints,

        .format_attrs           = amd_format_attr,
        .events_sysfs_show      = amd_event_sysfs_show,

        .cpu_prepare            = amd_pmu_cpu_prepare,
        .cpu_starting           = amd_pmu_cpu_starting,
        .cpu_dead               = amd_pmu_cpu_dead,

        .amd_nb_constraints     = 1,
};

static int __init amd_core_pmu_init(void)
{
        if (!cpu_has_perfctr_core)
                return 0;

        switch (boot_cpu_data.x86) {
        case 0x15:
                pr_cont("Fam15h ");
                x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
                break;
        case 0x17:
                pr_cont("Fam17h ");
                /*
                 * In family 17h, there are no event constraints in the PMC hardware.
                 * We fallback to using default amd_get_event_constraints.
                 */
                break;
        default:
                pr_err("core perfctr but no constraints; unknown hardware!\n");
                return -ENODEV;
        }

        /*
         * If core performance counter extensions exists, we must use
         * MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also
         * amd_pmu_addr_offset().
         */
        x86_pmu.eventsel        = MSR_F15H_PERF_CTL;
        x86_pmu.perfctr         = MSR_F15H_PERF_CTR;
        x86_pmu.num_counters    = AMD64_NUM_COUNTERS_CORE;
        /*
         * AMD Core perfctr has separate MSRs for the NB events, see
         * the amd/uncore.c driver.
         */
        x86_pmu.amd_nb_constraints = 0;

        pr_cont("core perfctr, ");
        return 0;
}

__init int amd_pmu_init(void)
{
        int ret;

        /* Performance-monitoring supported from K7 and later: */
        if (boot_cpu_data.x86 < 6)
                return -ENODEV;

        x86_pmu = amd_pmu;

        ret = amd_core_pmu_init();
        if (ret)
                return ret;

        if (num_possible_cpus() == 1) {
                /*
                 * No point in allocating data structures to serialize
                 * against other CPUs, when there is only the one CPU.
                 */
                x86_pmu.amd_nb_constraints = 0;
        }

        /* Events are common for all AMDs */
        memcpy(hw_cache_event_ids, amd_hw_cache_event_ids,
               sizeof(hw_cache_event_ids));

        return 0;
}

void amd_pmu_enable_virt(void)
{
        struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);

        cpuc->perf_ctr_virt_mask = 0;

        /* Reload all events */
        x86_pmu_disable_all();
        x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_enable_virt);

void amd_pmu_disable_virt(void)
{
        struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);

        /*
         * We only mask out the Host-only bit so that host-only counting works
         * when SVM is disabled. If someone sets up a guest-only counter when
         * SVM is disabled the Guest-only bits still gets set and the counter
         * will not count anything.
         */
        cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;

        /* Reload all events */
        x86_pmu_disable_all();
        x86_pmu_enable_all(0);
}
EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);