/*
 * perf_event_intel_rapl.c: support Intel RAPL energy consumption counters
 * Copyright (C) 2013 Google, Inc., Stephane Eranian
 *
 * Intel RAPL interface is specified in the IA-32 Manual Vol3b
 * section 14.7.1 (September 2013)
 *
 * RAPL provides more controls than just reporting energy consumption
 * however here we only expose the 3 energy consumption free running
 * counters (pp0, pkg, dram).
 *
 * Each of those counters increments in a power unit defined by the
 * RAPL_POWER_UNIT MSR. On SandyBridge, this unit is 1/(2^16) Joules
 * but it can vary.
 *
 * Counter to rapl events mappings:
 *
 *  pp0 counter: consumption of all physical cores (power plane 0)
 *        event: rapl_energy_cores
 *    perf code: 0x1
 *
 *  pkg counter: consumption of the whole processor package
 *        event: rapl_energy_pkg
 *    perf code: 0x2
 *
 * dram counter: consumption of the dram domain (servers only)
 *        event: rapl_energy_dram
 *    perf code: 0x3
 *
 * dram counter: consumption of the builtin-gpu domain (client only)
 *        event: rapl_energy_gpu
 *    perf code: 0x4
 *
 * We manage those counters as free running (read-only). They may be
 * use simultaneously by other tools, such as turbostat.
 *
 * The events only support system-wide mode counting. There is no
 * sampling support because it does not make sense and is not
 * supported by the RAPL hardware.
 *
 * Because we want to avoid floating-point operations in the kernel,
 * the events are all reported in fixed point arithmetic (32.32).
 * Tools must adjust the counts to convert them to Watts using
 * the duration of the measurement. Tools may use a function such as
 * ldexp(raw_count, -32);
 */
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/perf_event.h>
#include <asm/cpu_device_id.h>
#include "perf_event.h"

/*
 * RAPL energy status counters
 */
#define RAPL_IDX_PP0_NRG_STAT   0       /* all cores */
#define INTEL_RAPL_PP0          0x1     /* pseudo-encoding */
#define RAPL_IDX_PKG_NRG_STAT   1       /* entire package */
#define INTEL_RAPL_PKG          0x2     /* pseudo-encoding */
#define RAPL_IDX_RAM_NRG_STAT   2       /* DRAM */
#define INTEL_RAPL_RAM          0x3     /* pseudo-encoding */
#define RAPL_IDX_PP1_NRG_STAT   3       /* gpu */
#define INTEL_RAPL_PP1          0x4     /* pseudo-encoding */

#define NR_RAPL_DOMAINS         0x4
static const char *rapl_domain_names[NR_RAPL_DOMAINS] __initconst = {
        "pp0-core",
        "package",
        "dram",
        "pp1-gpu",
};

/* Clients have PP0, PKG */
#define RAPL_IDX_CLN    (1<<RAPL_IDX_PP0_NRG_STAT|\
                         1<<RAPL_IDX_PKG_NRG_STAT|\
                         1<<RAPL_IDX_PP1_NRG_STAT)

/* Servers have PP0, PKG, RAM */
#define RAPL_IDX_SRV    (1<<RAPL_IDX_PP0_NRG_STAT|\
                         1<<RAPL_IDX_PKG_NRG_STAT|\
                         1<<RAPL_IDX_RAM_NRG_STAT)

/* Servers have PP0, PKG, RAM, PP1 */
#define RAPL_IDX_HSW    (1<<RAPL_IDX_PP0_NRG_STAT|\
                         1<<RAPL_IDX_PKG_NRG_STAT|\
                         1<<RAPL_IDX_RAM_NRG_STAT|\
                         1<<RAPL_IDX_PP1_NRG_STAT)

/*
 * event code: LSB 8 bits, passed in attr->config
 * any other bit is reserved
 */
#define RAPL_EVENT_MASK 0xFFULL

#define DEFINE_RAPL_FORMAT_ATTR(_var, _name, _format)           \
static ssize_t __rapl_##_var##_show(struct kobject *kobj,       \
                                struct kobj_attribute *attr,    \
                                char *page)                     \
{                                                               \
        BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE);             \
        return sprintf(page, _format "\n");                     \
}                                                               \
static struct kobj_attribute format_attr_##_var =               \
        __ATTR(_name, 0444, __rapl_##_var##_show, NULL)

#define RAPL_EVENT_DESC(_name, _config)                         \
{                                                               \
        .attr   = __ATTR(_name, 0444, rapl_event_show, NULL),   \
        .config = _config,                                      \
}

#define RAPL_CNTR_WIDTH 32 /* 32-bit rapl counters */

#define RAPL_EVENT_ATTR_STR(_name, v, str)                              \
static struct perf_pmu_events_attr event_attr_##v = {                   \
        .attr           = __ATTR(_name, 0444, rapl_sysfs_show, NULL),   \
        .id             = 0,                                            \
        .event_str      = str,                                          \
};

struct rapl_pmu {
        spinlock_t       lock;
        int              n_active; /* number of active events */
        struct list_head active_list;
        struct pmu       *pmu; /* pointer to rapl_pmu_class */
        ktime_t          timer_interval; /* in ktime_t unit */
        struct hrtimer   hrtimer;
};

static int rapl_hw_unit[NR_RAPL_DOMAINS] __read_mostly;  /* 1/2^hw_unit Joule */
static struct pmu rapl_pmu_class;
static cpumask_t rapl_cpu_mask;
static int rapl_cntr_mask;

static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu);
static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu_to_free);

static struct x86_pmu_quirk *rapl_quirks;
static inline u64 rapl_read_counter(struct perf_event *event)
{
        u64 raw;
        rdmsrl(event->hw.event_base, raw);
        return raw;
}

#define rapl_add_quirk(func_)                                           \
do {                                                                    \
        static struct x86_pmu_quirk __quirk __initdata = {              \
                .func = func_,                                          \
        };                                                              \
        __quirk.next = rapl_quirks;                                     \
        rapl_quirks = &__quirk;                                         \
} while (0)

static inline u64 rapl_scale(u64 v, int cfg)
{
        if (cfg > NR_RAPL_DOMAINS) {
                pr_warn("invalid domain %d, failed to scale data\n", cfg);
                return v;
        }
        /*
         * scale delta to smallest unit (1/2^32)
         * users must then scale back: count * 1/(1e9*2^32) to get Joules
         * or use ldexp(count, -32).
         * Watts = Joules/Time delta
         */
        return v << (32 - rapl_hw_unit[cfg - 1]);
}

static u64 rapl_event_update(struct perf_event *event)
{
        struct hw_perf_event *hwc = &event->hw;
        u64 prev_raw_count, new_raw_count;
        s64 delta, sdelta;
        int shift = RAPL_CNTR_WIDTH;

again:
        prev_raw_count = local64_read(&hwc->prev_count);
        rdmsrl(event->hw.event_base, new_raw_count);

        if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
                            new_raw_count) != prev_raw_count) {
                cpu_relax();
                goto again;
        }

        /*
         * Now we have the new raw value and have updated the prev
         * timestamp already. We can now calculate the elapsed delta
         * (event-)time and add that to the generic event.
         *
         * Careful, not all hw sign-extends above the physical width
         * of the count.
         */
        delta = (new_raw_count << shift) - (prev_raw_count << shift);
        delta >>= shift;

        sdelta = rapl_scale(delta, event->hw.config);

        local64_add(sdelta, &event->count);

        return new_raw_count;
}

static void rapl_start_hrtimer(struct rapl_pmu *pmu)
{
        __hrtimer_start_range_ns(&pmu->hrtimer,
                        pmu->timer_interval, 0,
                        HRTIMER_MODE_REL_PINNED, 0);
}

static void rapl_stop_hrtimer(struct rapl_pmu *pmu)
{
        hrtimer_cancel(&pmu->hrtimer);
}

static enum hrtimer_restart rapl_hrtimer_handle(struct hrtimer *hrtimer)
{
        struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
        struct perf_event *event;
        unsigned long flags;

        if (!pmu->n_active)
                return HRTIMER_NORESTART;

        spin_lock_irqsave(&pmu->lock, flags);

        list_for_each_entry(event, &pmu->active_list, active_entry) {
                rapl_event_update(event);
        }

        spin_unlock_irqrestore(&pmu->lock, flags);

        hrtimer_forward_now(hrtimer, pmu->timer_interval);

        return HRTIMER_RESTART;
}

static void rapl_hrtimer_init(struct rapl_pmu *pmu)
{
        struct hrtimer *hr = &pmu->hrtimer;

        hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
        hr->function = rapl_hrtimer_handle;
}

static void __rapl_pmu_event_start(struct rapl_pmu *pmu,
                                   struct perf_event *event)
{
        if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
                return;

        event->hw.state = 0;

        list_add_tail(&event->active_entry, &pmu->active_list);

        local64_set(&event->hw.prev_count, rapl_read_counter(event));

        pmu->n_active++;
        if (pmu->n_active == 1)
                rapl_start_hrtimer(pmu);
}

static void rapl_pmu_event_start(struct perf_event *event, int mode)
{
        struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
        unsigned long flags;

        spin_lock_irqsave(&pmu->lock, flags);
        __rapl_pmu_event_start(pmu, event);
        spin_unlock_irqrestore(&pmu->lock, flags);
}

static void rapl_pmu_event_stop(struct perf_event *event, int mode)
{
        struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
        struct hw_perf_event *hwc = &event->hw;
        unsigned long flags;

        spin_lock_irqsave(&pmu->lock, flags);

        /* mark event as deactivated and stopped */
        if (!(hwc->state & PERF_HES_STOPPED)) {
                WARN_ON_ONCE(pmu->n_active <= 0);
                pmu->n_active--;
                if (pmu->n_active == 0)
                        rapl_stop_hrtimer(pmu);

                list_del(&event->active_entry);

                WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
                hwc->state |= PERF_HES_STOPPED;
        }

        /* check if update of sw counter is necessary */
        if ((mode & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
                /*
                 * Drain the remaining delta count out of a event
                 * that we are disabling:
                 */
                rapl_event_update(event);
                hwc->state |= PERF_HES_UPTODATE;
        }

        spin_unlock_irqrestore(&pmu->lock, flags);
}

static int rapl_pmu_event_add(struct perf_event *event, int mode)
{
        struct rapl_pmu *pmu = __this_cpu_read(rapl_pmu);
        struct hw_perf_event *hwc = &event->hw;
        unsigned long flags;

        spin_lock_irqsave(&pmu->lock, flags);

        hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;

        if (mode & PERF_EF_START)
                __rapl_pmu_event_start(pmu, event);

        spin_unlock_irqrestore(&pmu->lock, flags);

        return 0;
}

static void rapl_pmu_event_del(struct perf_event *event, int flags)
{
        rapl_pmu_event_stop(event, PERF_EF_UPDATE);
}

static int rapl_pmu_event_init(struct perf_event *event)
{
        u64 cfg = event->attr.config & RAPL_EVENT_MASK;
        int bit, msr, ret = 0;

        /* only look at RAPL events */
        if (event->attr.type != rapl_pmu_class.type)
                return -ENOENT;

        /* check only supported bits are set */
        if (event->attr.config & ~RAPL_EVENT_MASK)
                return -EINVAL;

        /*
         * check event is known (determines counter)
         */
        switch (cfg) {
        case INTEL_RAPL_PP0:
                bit = RAPL_IDX_PP0_NRG_STAT;
                msr = MSR_PP0_ENERGY_STATUS;
                break;
        case INTEL_RAPL_PKG:
                bit = RAPL_IDX_PKG_NRG_STAT;
                msr = MSR_PKG_ENERGY_STATUS;
                break;
        case INTEL_RAPL_RAM:
                bit = RAPL_IDX_RAM_NRG_STAT;
                msr = MSR_DRAM_ENERGY_STATUS;
                break;
        case INTEL_RAPL_PP1:
                bit = RAPL_IDX_PP1_NRG_STAT;
                msr = MSR_PP1_ENERGY_STATUS;
                break;
        default:
                return -EINVAL;
        }
        /* check event supported */
        if (!(rapl_cntr_mask & (1 << bit)))
                return -EINVAL;

        /* unsupported modes and filters */
        if (event->attr.exclude_user   ||
            event->attr.exclude_kernel ||
            event->attr.exclude_hv     ||
            event->attr.exclude_idle   ||
            event->attr.exclude_host   ||
            event->attr.exclude_guest  ||
            event->attr.sample_period) /* no sampling */
                return -EINVAL;

        /* must be done before validate_group */
        event->hw.event_base = msr;
        event->hw.config = cfg;
        event->hw.idx = bit;

        return ret;
}

static void rapl_pmu_event_read(struct perf_event *event)
{
        rapl_event_update(event);
}

static ssize_t rapl_get_attr_cpumask(struct device *dev,
                                struct device_attribute *attr, char *buf)
{
        return cpumap_print_to_pagebuf(true, buf, &rapl_cpu_mask);
}

static DEVICE_ATTR(cpumask, S_IRUGO, rapl_get_attr_cpumask, NULL);

static struct attribute *rapl_pmu_attrs[] = {
        &dev_attr_cpumask.attr,
        NULL,
};

static struct attribute_group rapl_pmu_attr_group = {
        .attrs = rapl_pmu_attrs,
};

static ssize_t rapl_sysfs_show(struct device *dev,
                               struct device_attribute *attr,
                               char *page)
{
        struct perf_pmu_events_attr *pmu_attr = \
                container_of(attr, struct perf_pmu_events_attr, attr);

        if (pmu_attr->event_str)
                return sprintf(page, "%s", pmu_attr->event_str);

        return 0;
}

RAPL_EVENT_ATTR_STR(energy-cores, rapl_cores, "event=0x01");
RAPL_EVENT_ATTR_STR(energy-pkg  ,   rapl_pkg, "event=0x02");
RAPL_EVENT_ATTR_STR(energy-ram  ,   rapl_ram, "event=0x03");
RAPL_EVENT_ATTR_STR(energy-gpu  ,   rapl_gpu, "event=0x04");

RAPL_EVENT_ATTR_STR(energy-cores.unit, rapl_cores_unit, "Joules");
RAPL_EVENT_ATTR_STR(energy-pkg.unit  ,   rapl_pkg_unit, "Joules");
RAPL_EVENT_ATTR_STR(energy-ram.unit  ,   rapl_ram_unit, "Joules");
RAPL_EVENT_ATTR_STR(energy-gpu.unit  ,   rapl_gpu_unit, "Joules");

/*
 * we compute in 0.23 nJ increments regardless of MSR
 */
RAPL_EVENT_ATTR_STR(energy-cores.scale, rapl_cores_scale, "2.3283064365386962890625e-10");
RAPL_EVENT_ATTR_STR(energy-pkg.scale,     rapl_pkg_scale, "2.3283064365386962890625e-10");
RAPL_EVENT_ATTR_STR(energy-ram.scale,     rapl_ram_scale, "2.3283064365386962890625e-10");
RAPL_EVENT_ATTR_STR(energy-gpu.scale,     rapl_gpu_scale, "2.3283064365386962890625e-10");

static struct attribute *rapl_events_srv_attr[] = {
        EVENT_PTR(rapl_cores),
        EVENT_PTR(rapl_pkg),
        EVENT_PTR(rapl_ram),

        EVENT_PTR(rapl_cores_unit),
        EVENT_PTR(rapl_pkg_unit),
        EVENT_PTR(rapl_ram_unit),

        EVENT_PTR(rapl_cores_scale),
        EVENT_PTR(rapl_pkg_scale),
        EVENT_PTR(rapl_ram_scale),
        NULL,
};

static struct attribute *rapl_events_cln_attr[] = {
        EVENT_PTR(rapl_cores),
        EVENT_PTR(rapl_pkg),
        EVENT_PTR(rapl_gpu),

        EVENT_PTR(rapl_cores_unit),
        EVENT_PTR(rapl_pkg_unit),
        EVENT_PTR(rapl_gpu_unit),

        EVENT_PTR(rapl_cores_scale),
        EVENT_PTR(rapl_pkg_scale),
        EVENT_PTR(rapl_gpu_scale),
        NULL,
};

static struct attribute *rapl_events_hsw_attr[] = {
        EVENT_PTR(rapl_cores),
        EVENT_PTR(rapl_pkg),
        EVENT_PTR(rapl_gpu),
        EVENT_PTR(rapl_ram),

        EVENT_PTR(rapl_cores_unit),
        EVENT_PTR(rapl_pkg_unit),
        EVENT_PTR(rapl_gpu_unit),
        EVENT_PTR(rapl_ram_unit),

        EVENT_PTR(rapl_cores_scale),
        EVENT_PTR(rapl_pkg_scale),
        EVENT_PTR(rapl_gpu_scale),
        EVENT_PTR(rapl_ram_scale),
        NULL,
};

static struct attribute_group rapl_pmu_events_group = {
        .name = "events",
        .attrs = NULL, /* patched at runtime */
};

DEFINE_RAPL_FORMAT_ATTR(event, event, "config:0-7");
static struct attribute *rapl_formats_attr[] = {
        &format_attr_event.attr,
        NULL,
};

static struct attribute_group rapl_pmu_format_group = {
        .name = "format",
        .attrs = rapl_formats_attr,
};

const struct attribute_group *rapl_attr_groups[] = {
        &rapl_pmu_attr_group,
        &rapl_pmu_format_group,
        &rapl_pmu_events_group,
        NULL,
};

static struct pmu rapl_pmu_class = {
        .attr_groups    = rapl_attr_groups,
        .task_ctx_nr    = perf_invalid_context, /* system-wide only */
        .event_init     = rapl_pmu_event_init,
        .add            = rapl_pmu_event_add, /* must have */
        .del            = rapl_pmu_event_del, /* must have */
        .start          = rapl_pmu_event_start,
        .stop           = rapl_pmu_event_stop,
        .read           = rapl_pmu_event_read,
};

static void rapl_cpu_exit(int cpu)
{
        struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
        int i, phys_id = topology_physical_package_id(cpu);
        int target = -1;

        /* find a new cpu on same package */
        for_each_online_cpu(i) {
                if (i == cpu)
                        continue;
                if (phys_id == topology_physical_package_id(i)) {
                        target = i;
                        break;
                }
        }
        /*
         * clear cpu from cpumask
         * if was set in cpumask and still some cpu on package,
         * then move to new cpu
         */
        if (cpumask_test_and_clear_cpu(cpu, &rapl_cpu_mask) && target >= 0)
                cpumask_set_cpu(target, &rapl_cpu_mask);

        WARN_ON(cpumask_empty(&rapl_cpu_mask));
        /*
         * migrate events and context to new cpu
         */
        if (target >= 0)
                perf_pmu_migrate_context(pmu->pmu, cpu, target);

        /* cancel overflow polling timer for CPU */
        rapl_stop_hrtimer(pmu);
}

static void rapl_cpu_init(int cpu)
{
        int i, phys_id = topology_physical_package_id(cpu);

        /* check if phys_is is already covered */
        for_each_cpu(i, &rapl_cpu_mask) {
                if (phys_id == topology_physical_package_id(i))
                        return;
        }
        /* was not found, so add it */
        cpumask_set_cpu(cpu, &rapl_cpu_mask);
}

static __init void rapl_hsw_server_quirk(void)
{
        /*
         * DRAM domain on HSW server has fixed energy unit which can be
         * different than the unit from power unit MSR.
         * "Intel Xeon Processor E5-1600 and E5-2600 v3 Product Families, V2
         * of 2. Datasheet, September 2014, Reference Number: 330784-001 "
         */
        rapl_hw_unit[RAPL_IDX_RAM_NRG_STAT] = 16;
}

static int rapl_cpu_prepare(int cpu)
{
        struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
        int phys_id = topology_physical_package_id(cpu);
        u64 ms;

        if (pmu)
                return 0;

        if (phys_id < 0)
                return -1;

        pmu = kzalloc_node(sizeof(*pmu), GFP_KERNEL, cpu_to_node(cpu));
        if (!pmu)
                return -1;
        spin_lock_init(&pmu->lock);

        INIT_LIST_HEAD(&pmu->active_list);

        pmu->pmu = &rapl_pmu_class;

        /*
         * use reference of 200W for scaling the timeout
         * to avoid missing counter overflows.
         * 200W = 200 Joules/sec
         * divide interval by 2 to avoid lockstep (2 * 100)
         * if hw unit is 32, then we use 2 ms 1/200/2
         */
        if (rapl_hw_unit[0] < 32)
                ms = (1000 / (2 * 100)) * (1ULL << (32 - rapl_hw_unit[0] - 1));
        else
                ms = 2;

        pmu->timer_interval = ms_to_ktime(ms);

        rapl_hrtimer_init(pmu);

        /* set RAPL pmu for this cpu for now */
        per_cpu(rapl_pmu, cpu) = pmu;
        per_cpu(rapl_pmu_to_free, cpu) = NULL;

        return 0;
}

static void rapl_cpu_kfree(int cpu)
{
        struct rapl_pmu *pmu = per_cpu(rapl_pmu_to_free, cpu);

        kfree(pmu);

        per_cpu(rapl_pmu_to_free, cpu) = NULL;
}

static int rapl_cpu_dying(int cpu)
{
        struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);

        if (!pmu)
                return 0;

        per_cpu(rapl_pmu, cpu) = NULL;

        per_cpu(rapl_pmu_to_free, cpu) = pmu;

        return 0;
}

static int rapl_cpu_notifier(struct notifier_block *self,
                             unsigned long action, void *hcpu)
{
        unsigned int cpu = (long)hcpu;

        switch (action & ~CPU_TASKS_FROZEN) {
        case CPU_UP_PREPARE:
                rapl_cpu_prepare(cpu);
                break;
        case CPU_STARTING:
                rapl_cpu_init(cpu);
                break;
        case CPU_UP_CANCELED:
        case CPU_DYING:
                rapl_cpu_dying(cpu);
                break;
        case CPU_ONLINE:
        case CPU_DEAD:
                rapl_cpu_kfree(cpu);
                break;
        case CPU_DOWN_PREPARE:
                rapl_cpu_exit(cpu);
                break;
        default:
                break;
        }

        return NOTIFY_OK;
}

static int rapl_check_hw_unit(void)
{
        u64 msr_rapl_power_unit_bits;
        int i;

        /* protect rdmsrl() to handle virtualization */
        if (rdmsrl_safe(MSR_RAPL_POWER_UNIT, &msr_rapl_power_unit_bits))
                return -1;
        for (i = 0; i < NR_RAPL_DOMAINS; i++)
                rapl_hw_unit[i] = (msr_rapl_power_unit_bits >> 8) & 0x1FULL;

        return 0;
}

static const struct x86_cpu_id rapl_cpu_match[] = {
        [0] = { .vendor = X86_VENDOR_INTEL, .family = 6 },
        [1] = {},
};

static int __init rapl_pmu_init(void)
{
        struct rapl_pmu *pmu;
        int cpu, ret;
        struct x86_pmu_quirk *quirk;
        int i;

        /*
         * check for Intel processor family 6
         */
        if (!x86_match_cpu(rapl_cpu_match))
                return 0;

        /* check supported CPU */
        switch (boot_cpu_data.x86_model) {
        case 42: /* Sandy Bridge */
        case 58: /* Ivy Bridge */
                rapl_cntr_mask = RAPL_IDX_CLN;
                rapl_pmu_events_group.attrs = rapl_events_cln_attr;
                break;
        case 63: /* Haswell-Server */
                rapl_add_quirk(rapl_hsw_server_quirk);
                rapl_cntr_mask = RAPL_IDX_SRV;
                rapl_pmu_events_group.attrs = rapl_events_srv_attr;
                break;
        case 60: /* Haswell */
        case 69: /* Haswell-Celeron */
        case 61: /* Broadwell */
                rapl_cntr_mask = RAPL_IDX_HSW;
                rapl_pmu_events_group.attrs = rapl_events_hsw_attr;
                break;
        case 45: /* Sandy Bridge-EP */
        case 62: /* IvyTown */
                rapl_cntr_mask = RAPL_IDX_SRV;
                rapl_pmu_events_group.attrs = rapl_events_srv_attr;
                break;

        default:
                /* unsupported */
                return 0;
        }
        ret = rapl_check_hw_unit();
        if (ret)
                return ret;

        /* run cpu model quirks */
        for (quirk = rapl_quirks; quirk; quirk = quirk->next)
                quirk->func();
        cpu_notifier_register_begin();

        for_each_online_cpu(cpu) {
                ret = rapl_cpu_prepare(cpu);
                if (ret)
                        goto out;
                rapl_cpu_init(cpu);
        }

        __perf_cpu_notifier(rapl_cpu_notifier);

        ret = perf_pmu_register(&rapl_pmu_class, "power", -1);
        if (WARN_ON(ret)) {
                pr_info("RAPL PMU detected, registration failed (%d), RAPL PMU disabled\n", ret);
                cpu_notifier_register_done();
                return -1;
        }

        pmu = __this_cpu_read(rapl_pmu);

        pr_info("RAPL PMU detected,"
                " API unit is 2^-32 Joules,"
                " %d fixed counters"
                " %llu ms ovfl timer\n",
                hweight32(rapl_cntr_mask),
                ktime_to_ms(pmu->timer_interval));
        for (i = 0; i < NR_RAPL_DOMAINS; i++) {
                if (rapl_cntr_mask & (1 << i)) {
                        pr_info("hw unit of domain %s 2^-%d Joules\n",
                                rapl_domain_names[i], rapl_hw_unit[i]);
                }
        }
out:
        cpu_notifier_register_done();

        return 0;
}
device_initcall(rapl_pmu_init);