// SPDX-License-Identifier: GPL-2.0
/*
 *      Routines to identify caches on Intel CPU.
 *
 *      Changes:
 *      Venkatesh Pallipadi     : Adding cache identification through cpuid(4)
 *      Ashok Raj <ashok.raj@intel.com>: Work with CPU hotplug infrastructure.
 *      Andi Kleen / Andreas Herrmann   : CPUID4 emulation on AMD.
 */

#include <linux/slab.h>
#include <linux/cacheinfo.h>
#include <linux/cpu.h>
#include <linux/sched.h>
#include <linux/capability.h>
#include <linux/sysfs.h>
#include <linux/pci.h>

#include <asm/cpufeature.h>
#include <asm/cacheinfo.h>
#include <asm/amd_nb.h>
#include <asm/smp.h>

#include "cpu.h"

#define LVL_1_INST      1
#define LVL_1_DATA      2
#define LVL_2           3
#define LVL_3           4
#define LVL_TRACE       5

struct _cache_table {
        unsigned char descriptor;
        char cache_type;
        short size;
};

#define MB(x)   ((x) * 1024)

/* All the cache descriptor types we care about (no TLB or
   trace cache entries) */

static const struct _cache_table cache_table[] =
{
        { 0x06, LVL_1_INST, 8 },        /* 4-way set assoc, 32 byte line size */
        { 0x08, LVL_1_INST, 16 },       /* 4-way set assoc, 32 byte line size */
        { 0x09, LVL_1_INST, 32 },       /* 4-way set assoc, 64 byte line size */
        { 0x0a, LVL_1_DATA, 8 },        /* 2 way set assoc, 32 byte line size */
        { 0x0c, LVL_1_DATA, 16 },       /* 4-way set assoc, 32 byte line size */
        { 0x0d, LVL_1_DATA, 16 },       /* 4-way set assoc, 64 byte line size */
        { 0x0e, LVL_1_DATA, 24 },       /* 6-way set assoc, 64 byte line size */
        { 0x21, LVL_2,      256 },      /* 8-way set assoc, 64 byte line size */
        { 0x22, LVL_3,      512 },      /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x23, LVL_3,      MB(1) },    /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x25, LVL_3,      MB(2) },    /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x29, LVL_3,      MB(4) },    /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x2c, LVL_1_DATA, 32 },       /* 8-way set assoc, 64 byte line size */
        { 0x30, LVL_1_INST, 32 },       /* 8-way set assoc, 64 byte line size */
        { 0x39, LVL_2,      128 },      /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x3a, LVL_2,      192 },      /* 6-way set assoc, sectored cache, 64 byte line size */
        { 0x3b, LVL_2,      128 },      /* 2-way set assoc, sectored cache, 64 byte line size */
        { 0x3c, LVL_2,      256 },      /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x3d, LVL_2,      384 },      /* 6-way set assoc, sectored cache, 64 byte line size */
        { 0x3e, LVL_2,      512 },      /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x3f, LVL_2,      256 },      /* 2-way set assoc, 64 byte line size */
        { 0x41, LVL_2,      128 },      /* 4-way set assoc, 32 byte line size */
        { 0x42, LVL_2,      256 },      /* 4-way set assoc, 32 byte line size */
        { 0x43, LVL_2,      512 },      /* 4-way set assoc, 32 byte line size */
        { 0x44, LVL_2,      MB(1) },    /* 4-way set assoc, 32 byte line size */
        { 0x45, LVL_2,      MB(2) },    /* 4-way set assoc, 32 byte line size */
        { 0x46, LVL_3,      MB(4) },    /* 4-way set assoc, 64 byte line size */
        { 0x47, LVL_3,      MB(8) },    /* 8-way set assoc, 64 byte line size */
        { 0x48, LVL_2,      MB(3) },    /* 12-way set assoc, 64 byte line size */
        { 0x49, LVL_3,      MB(4) },    /* 16-way set assoc, 64 byte line size */
        { 0x4a, LVL_3,      MB(6) },    /* 12-way set assoc, 64 byte line size */
        { 0x4b, LVL_3,      MB(8) },    /* 16-way set assoc, 64 byte line size */
        { 0x4c, LVL_3,      MB(12) },   /* 12-way set assoc, 64 byte line size */
        { 0x4d, LVL_3,      MB(16) },   /* 16-way set assoc, 64 byte line size */
        { 0x4e, LVL_2,      MB(6) },    /* 24-way set assoc, 64 byte line size */
        { 0x60, LVL_1_DATA, 16 },       /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x66, LVL_1_DATA, 8 },        /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x67, LVL_1_DATA, 16 },       /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x68, LVL_1_DATA, 32 },       /* 4-way set assoc, sectored cache, 64 byte line size */
        { 0x70, LVL_TRACE,  12 },       /* 8-way set assoc */
        { 0x71, LVL_TRACE,  16 },       /* 8-way set assoc */
        { 0x72, LVL_TRACE,  32 },       /* 8-way set assoc */
        { 0x73, LVL_TRACE,  64 },       /* 8-way set assoc */
        { 0x78, LVL_2,      MB(1) },    /* 4-way set assoc, 64 byte line size */
        { 0x79, LVL_2,      128 },      /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x7a, LVL_2,      256 },      /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x7b, LVL_2,      512 },      /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x7c, LVL_2,      MB(1) },    /* 8-way set assoc, sectored cache, 64 byte line size */
        { 0x7d, LVL_2,      MB(2) },    /* 8-way set assoc, 64 byte line size */
        { 0x7f, LVL_2,      512 },      /* 2-way set assoc, 64 byte line size */
        { 0x80, LVL_2,      512 },      /* 8-way set assoc, 64 byte line size */
        { 0x82, LVL_2,      256 },      /* 8-way set assoc, 32 byte line size */
        { 0x83, LVL_2,      512 },      /* 8-way set assoc, 32 byte line size */
        { 0x84, LVL_2,      MB(1) },    /* 8-way set assoc, 32 byte line size */
        { 0x85, LVL_2,      MB(2) },    /* 8-way set assoc, 32 byte line size */
        { 0x86, LVL_2,      512 },      /* 4-way set assoc, 64 byte line size */
        { 0x87, LVL_2,      MB(1) },    /* 8-way set assoc, 64 byte line size */
        { 0xd0, LVL_3,      512 },      /* 4-way set assoc, 64 byte line size */
        { 0xd1, LVL_3,      MB(1) },    /* 4-way set assoc, 64 byte line size */
        { 0xd2, LVL_3,      MB(2) },    /* 4-way set assoc, 64 byte line size */
        { 0xd6, LVL_3,      MB(1) },    /* 8-way set assoc, 64 byte line size */
        { 0xd7, LVL_3,      MB(2) },    /* 8-way set assoc, 64 byte line size */
        { 0xd8, LVL_3,      MB(4) },    /* 12-way set assoc, 64 byte line size */
        { 0xdc, LVL_3,      MB(2) },    /* 12-way set assoc, 64 byte line size */
        { 0xdd, LVL_3,      MB(4) },    /* 12-way set assoc, 64 byte line size */
        { 0xde, LVL_3,      MB(8) },    /* 12-way set assoc, 64 byte line size */
        { 0xe2, LVL_3,      MB(2) },    /* 16-way set assoc, 64 byte line size */
        { 0xe3, LVL_3,      MB(4) },    /* 16-way set assoc, 64 byte line size */
        { 0xe4, LVL_3,      MB(8) },    /* 16-way set assoc, 64 byte line size */
        { 0xea, LVL_3,      MB(12) },   /* 24-way set assoc, 64 byte line size */
        { 0xeb, LVL_3,      MB(18) },   /* 24-way set assoc, 64 byte line size */
        { 0xec, LVL_3,      MB(24) },   /* 24-way set assoc, 64 byte line size */
        { 0x00, 0, 0}
};


enum _cache_type {
        CTYPE_NULL = 0,
        CTYPE_DATA = 1,
        CTYPE_INST = 2,
        CTYPE_UNIFIED = 3
};

union _cpuid4_leaf_eax {
        struct {
                enum _cache_type        type:5;
                unsigned int            level:3;
                unsigned int            is_self_initializing:1;
                unsigned int            is_fully_associative:1;
                unsigned int            reserved:4;
                unsigned int            num_threads_sharing:12;
                unsigned int            num_cores_on_die:6;
        } split;
        u32 full;
};

union _cpuid4_leaf_ebx {
        struct {
                unsigned int            coherency_line_size:12;
                unsigned int            physical_line_partition:10;
                unsigned int            ways_of_associativity:10;
        } split;
        u32 full;
};

union _cpuid4_leaf_ecx {
        struct {
                unsigned int            number_of_sets:32;
        } split;
        u32 full;
};

struct _cpuid4_info_regs {
        union _cpuid4_leaf_eax eax;
        union _cpuid4_leaf_ebx ebx;
        union _cpuid4_leaf_ecx ecx;
        unsigned int id;
        unsigned long size;
        struct amd_northbridge *nb;
};

static unsigned short num_cache_leaves;

/* AMD doesn't have CPUID4. Emulate it here to report the same
   information to the user.  This makes some assumptions about the machine:
   L2 not shared, no SMT etc. that is currently true on AMD CPUs.

   In theory the TLBs could be reported as fake type (they are in "dummy").
   Maybe later */
union l1_cache {
        struct {
                unsigned line_size:8;
                unsigned lines_per_tag:8;
                unsigned assoc:8;
                unsigned size_in_kb:8;
        };
        unsigned val;
};

union l2_cache {
        struct {
                unsigned line_size:8;
                unsigned lines_per_tag:4;
                unsigned assoc:4;
                unsigned size_in_kb:16;
        };
        unsigned val;
};

union l3_cache {
        struct {
                unsigned line_size:8;
                unsigned lines_per_tag:4;
                unsigned assoc:4;
                unsigned res:2;
                unsigned size_encoded:14;
        };
        unsigned val;
};

static const unsigned short assocs[] = {
        [1] = 1,
        [2] = 2,
        [4] = 4,
        [6] = 8,
        [8] = 16,
        [0xa] = 32,
        [0xb] = 48,
        [0xc] = 64,
        [0xd] = 96,
        [0xe] = 128,
        [0xf] = 0xffff /* fully associative - no way to show this currently */
};

static const unsigned char levels[] = { 1, 1, 2, 3 };
static const unsigned char types[] = { 1, 2, 3, 3 };

static const enum cache_type cache_type_map[] = {
        [CTYPE_NULL] = CACHE_TYPE_NOCACHE,
        [CTYPE_DATA] = CACHE_TYPE_DATA,
        [CTYPE_INST] = CACHE_TYPE_INST,
        [CTYPE_UNIFIED] = CACHE_TYPE_UNIFIED,
};

static void
amd_cpuid4(int leaf, union _cpuid4_leaf_eax *eax,
                     union _cpuid4_leaf_ebx *ebx,
                     union _cpuid4_leaf_ecx *ecx)
{
        unsigned dummy;
        unsigned line_size, lines_per_tag, assoc, size_in_kb;
        union l1_cache l1i, l1d;
        union l2_cache l2;
        union l3_cache l3;
        union l1_cache *l1 = &l1d;

        eax->full = 0;
        ebx->full = 0;
        ecx->full = 0;

        cpuid(0x80000005, &dummy, &dummy, &l1d.val, &l1i.val);
        cpuid(0x80000006, &dummy, &dummy, &l2.val, &l3.val);

        switch (leaf) {
        case 1:
                l1 = &l1i;
                /* fall through */
        case 0:
                if (!l1->val)
                        return;
                assoc = assocs[l1->assoc];
                line_size = l1->line_size;
                lines_per_tag = l1->lines_per_tag;
                size_in_kb = l1->size_in_kb;
                break;
        case 2:
                if (!l2.val)
                        return;
                assoc = assocs[l2.assoc];
                line_size = l2.line_size;
                lines_per_tag = l2.lines_per_tag;
                /* cpu_data has errata corrections for K7 applied */
                size_in_kb = __this_cpu_read(cpu_info.x86_cache_size);
                break;
        case 3:
                if (!l3.val)
                        return;
                assoc = assocs[l3.assoc];
                line_size = l3.line_size;
                lines_per_tag = l3.lines_per_tag;
                size_in_kb = l3.size_encoded * 512;
                if (boot_cpu_has(X86_FEATURE_AMD_DCM)) {
                        size_in_kb = size_in_kb >> 1;
                        assoc = assoc >> 1;
                }
                break;
        default:
                return;
        }

        eax->split.is_self_initializing = 1;
        eax->split.type = types[leaf];
        eax->split.level = levels[leaf];
        eax->split.num_threads_sharing = 0;
        eax->split.num_cores_on_die = __this_cpu_read(cpu_info.x86_max_cores) - 1;


        if (assoc == 0xffff)
                eax->split.is_fully_associative = 1;
        ebx->split.coherency_line_size = line_size - 1;
        ebx->split.ways_of_associativity = assoc - 1;
        ebx->split.physical_line_partition = lines_per_tag - 1;
        ecx->split.number_of_sets = (size_in_kb * 1024) / line_size /
                (ebx->split.ways_of_associativity + 1) - 1;
}

#if defined(CONFIG_AMD_NB) && defined(CONFIG_SYSFS)

/*
 * L3 cache descriptors
 */
static void amd_calc_l3_indices(struct amd_northbridge *nb)
{
        struct amd_l3_cache *l3 = &nb->l3_cache;
        unsigned int sc0, sc1, sc2, sc3;
        u32 val = 0;

        pci_read_config_dword(nb->misc, 0x1C4, &val);

        /* calculate subcache sizes */
        l3->subcaches[0] = sc0 = !(val & BIT(0));
        l3->subcaches[1] = sc1 = !(val & BIT(4));

        if (boot_cpu_data.x86 == 0x15) {
                l3->subcaches[0] = sc0 += !(val & BIT(1));
                l3->subcaches[1] = sc1 += !(val & BIT(5));
        }

        l3->subcaches[2] = sc2 = !(val & BIT(8))  + !(val & BIT(9));
        l3->subcaches[3] = sc3 = !(val & BIT(12)) + !(val & BIT(13));

        l3->indices = (max(max3(sc0, sc1, sc2), sc3) << 10) - 1;
}

/*
 * check whether a slot used for disabling an L3 index is occupied.
 * @l3: L3 cache descriptor
 * @slot: slot number (0..1)
 *
 * @returns: the disabled index if used or negative value if slot free.
 */
static int amd_get_l3_disable_slot(struct amd_northbridge *nb, unsigned slot)
{
        unsigned int reg = 0;

        pci_read_config_dword(nb->misc, 0x1BC + slot * 4, &reg);

        /* check whether this slot is activated already */
        if (reg & (3UL << 30))
                return reg & 0xfff;

        return -1;
}

static ssize_t show_cache_disable(struct cacheinfo *this_leaf, char *buf,
                                  unsigned int slot)
{
        int index;
        struct amd_northbridge *nb = this_leaf->priv;

        index = amd_get_l3_disable_slot(nb, slot);
        if (index >= 0)
                return sprintf(buf, "%d\n", index);

        return sprintf(buf, "FREE\n");
}

#define SHOW_CACHE_DISABLE(slot)                                        \
static ssize_t                                                          \
cache_disable_##slot##_show(struct device *dev,                         \
                            struct device_attribute *attr, char *buf)   \
{                                                                       \
        struct cacheinfo *this_leaf = dev_get_drvdata(dev);             \
        return show_cache_disable(this_leaf, buf, slot);                \
}
SHOW_CACHE_DISABLE(0)
SHOW_CACHE_DISABLE(1)

static void amd_l3_disable_index(struct amd_northbridge *nb, int cpu,
                                 unsigned slot, unsigned long idx)
{
        int i;

        idx |= BIT(30);

        /*
         *  disable index in all 4 subcaches
         */
        for (i = 0; i < 4; i++) {
                u32 reg = idx | (i << 20);

                if (!nb->l3_cache.subcaches[i])
                        continue;

                pci_write_config_dword(nb->misc, 0x1BC + slot * 4, reg);

                /*
                 * We need to WBINVD on a core on the node containing the L3
                 * cache which indices we disable therefore a simple wbinvd()
                 * is not sufficient.
                 */
                wbinvd_on_cpu(cpu);

                reg |= BIT(31);
                pci_write_config_dword(nb->misc, 0x1BC + slot * 4, reg);
        }
}

/*
 * disable a L3 cache index by using a disable-slot
 *
 * @l3:    L3 cache descriptor
 * @cpu:   A CPU on the node containing the L3 cache
 * @slot:  slot number (0..1)
 * @index: index to disable
 *
 * @return: 0 on success, error status on failure
 */
static int amd_set_l3_disable_slot(struct amd_northbridge *nb, int cpu,
                            unsigned slot, unsigned long index)
{
        int ret = 0;

        /*  check if @slot is already used or the index is already disabled */
        ret = amd_get_l3_disable_slot(nb, slot);
        if (ret >= 0)
                return -EEXIST;

        if (index > nb->l3_cache.indices)
                return -EINVAL;

        /* check whether the other slot has disabled the same index already */
        if (index == amd_get_l3_disable_slot(nb, !slot))
                return -EEXIST;

        amd_l3_disable_index(nb, cpu, slot, index);

        return 0;
}

static ssize_t store_cache_disable(struct cacheinfo *this_leaf,
                                   const char *buf, size_t count,
                                   unsigned int slot)
{
        unsigned long val = 0;
        int cpu, err = 0;
        struct amd_northbridge *nb = this_leaf->priv;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        cpu = cpumask_first(&this_leaf->shared_cpu_map);

        if (kstrtoul(buf, 10, &val) < 0)
                return -EINVAL;

        err = amd_set_l3_disable_slot(nb, cpu, slot, val);
        if (err) {
                if (err == -EEXIST)
                        pr_warn("L3 slot %d in use/index already disabled!\n",
                                   slot);
                return err;
        }
        return count;
}

#define STORE_CACHE_DISABLE(slot)                                       \
static ssize_t                                                          \
cache_disable_##slot##_store(struct device *dev,                        \
                             struct device_attribute *attr,             \
                             const char *buf, size_t count)             \
{                                                                       \
        struct cacheinfo *this_leaf = dev_get_drvdata(dev);             \
        return store_cache_disable(this_leaf, buf, count, slot);        \
}
STORE_CACHE_DISABLE(0)
STORE_CACHE_DISABLE(1)

static ssize_t subcaches_show(struct device *dev,
                              struct device_attribute *attr, char *buf)
{
        struct cacheinfo *this_leaf = dev_get_drvdata(dev);
        int cpu = cpumask_first(&this_leaf->shared_cpu_map);

        return sprintf(buf, "%x\n", amd_get_subcaches(cpu));
}

static ssize_t subcaches_store(struct device *dev,
                               struct device_attribute *attr,
                               const char *buf, size_t count)
{
        struct cacheinfo *this_leaf = dev_get_drvdata(dev);
        int cpu = cpumask_first(&this_leaf->shared_cpu_map);
        unsigned long val;

        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;

        if (kstrtoul(buf, 16, &val) < 0)
                return -EINVAL;

        if (amd_set_subcaches(cpu, val))
                return -EINVAL;

        return count;
}

static DEVICE_ATTR_RW(cache_disable_0);
static DEVICE_ATTR_RW(cache_disable_1);
static DEVICE_ATTR_RW(subcaches);

static umode_t
cache_private_attrs_is_visible(struct kobject *kobj,
                               struct attribute *attr, int unused)
{
        struct device *dev = kobj_to_dev(kobj);
        struct cacheinfo *this_leaf = dev_get_drvdata(dev);
        umode_t mode = attr->mode;

        if (!this_leaf->priv)
                return 0;

        if ((attr == &dev_attr_subcaches.attr) &&
            amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
                return mode;

        if ((attr == &dev_attr_cache_disable_0.attr ||
             attr == &dev_attr_cache_disable_1.attr) &&
            amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE))
                return mode;

        return 0;
}

static struct attribute_group cache_private_group = {
        .is_visible = cache_private_attrs_is_visible,
};

static void init_amd_l3_attrs(void)
{
        int n = 1;
        static struct attribute **amd_l3_attrs;

        if (amd_l3_attrs) /* already initialized */
                return;

        if (amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE))
                n += 2;
        if (amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
                n += 1;

        amd_l3_attrs = kcalloc(n, sizeof(*amd_l3_attrs), GFP_KERNEL);
        if (!amd_l3_attrs)
                return;

        n = 0;
        if (amd_nb_has_feature(AMD_NB_L3_INDEX_DISABLE)) {
                amd_l3_attrs[n++] = &dev_attr_cache_disable_0.attr;
                amd_l3_attrs[n++] = &dev_attr_cache_disable_1.attr;
        }
        if (amd_nb_has_feature(AMD_NB_L3_PARTITIONING))
                amd_l3_attrs[n++] = &dev_attr_subcaches.attr;

        cache_private_group.attrs = amd_l3_attrs;
}

const struct attribute_group *
cache_get_priv_group(struct cacheinfo *this_leaf)
{
        struct amd_northbridge *nb = this_leaf->priv;

        if (this_leaf->level < 3 || !nb)
                return NULL;

        if (nb && nb->l3_cache.indices)
                init_amd_l3_attrs();

        return &cache_private_group;
}

static void amd_init_l3_cache(struct _cpuid4_info_regs *this_leaf, int index)
{
        int node;

        /* only for L3, and not in virtualized environments */
        if (index < 3)
                return;

        node = amd_get_nb_id(smp_processor_id());
        this_leaf->nb = node_to_amd_nb(node);
        if (this_leaf->nb && !this_leaf->nb->l3_cache.indices)
                amd_calc_l3_indices(this_leaf->nb);
}
#else
#define amd_init_l3_cache(x, y)
#endif  /* CONFIG_AMD_NB && CONFIG_SYSFS */

static int
cpuid4_cache_lookup_regs(int index, struct _cpuid4_info_regs *this_leaf)
{
        union _cpuid4_leaf_eax  eax;
        union _cpuid4_leaf_ebx  ebx;
        union _cpuid4_leaf_ecx  ecx;
        unsigned                edx;

        if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) {
                if (boot_cpu_has(X86_FEATURE_TOPOEXT))
                        cpuid_count(0x8000001d, index, &eax.full,
                                    &ebx.full, &ecx.full, &edx);
                else
                        amd_cpuid4(index, &eax, &ebx, &ecx);
                amd_init_l3_cache(this_leaf, index);
        } else if (boot_cpu_data.x86_vendor == X86_VENDOR_HYGON) {
                cpuid_count(0x8000001d, index, &eax.full,
                            &ebx.full, &ecx.full, &edx);
                amd_init_l3_cache(this_leaf, index);
        } else {
                cpuid_count(4, index, &eax.full, &ebx.full, &ecx.full, &edx);
        }

        if (eax.split.type == CTYPE_NULL)
                return -EIO; /* better error ? */

        this_leaf->eax = eax;
        this_leaf->ebx = ebx;
        this_leaf->ecx = ecx;
        this_leaf->size = (ecx.split.number_of_sets          + 1) *
                          (ebx.split.coherency_line_size     + 1) *
                          (ebx.split.physical_line_partition + 1) *
                          (ebx.split.ways_of_associativity   + 1);
        return 0;
}

static int find_num_cache_leaves(struct cpuinfo_x86 *c)
{
        unsigned int            eax, ebx, ecx, edx, op;
        union _cpuid4_leaf_eax  cache_eax;
        int                     i = -1;

        if (c->x86_vendor == X86_VENDOR_AMD ||
            c->x86_vendor == X86_VENDOR_HYGON)
                op = 0x8000001d;
        else
                op = 4;

        do {
                ++i;
                /* Do cpuid(op) loop to find out num_cache_leaves */
                cpuid_count(op, i, &eax, &ebx, &ecx, &edx);
                cache_eax.full = eax;
        } while (cache_eax.split.type != CTYPE_NULL);
        return i;
}

void cacheinfo_amd_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)
{
        /*
         * We may have multiple LLCs if L3 caches exist, so check if we
         * have an L3 cache by looking at the L3 cache CPUID leaf.
         */
        if (!cpuid_edx(0x80000006))
                return;

        if (c->x86 < 0x17) {
                /* LLC is at the node level. */
                per_cpu(cpu_llc_id, cpu) = node_id;
        } else if (c->x86 == 0x17 && c->x86_model <= 0x1F) {
                /*
                 * LLC is at the core complex level.
                 * Core complex ID is ApicId[3] for these processors.
                 */
                per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
        } else {
                /*
                 * LLC ID is calculated from the number of threads sharing the
                 * cache.
                 * */
                u32 eax, ebx, ecx, edx, num_sharing_cache = 0;
                u32 llc_index = find_num_cache_leaves(c) - 1;

                cpuid_count(0x8000001d, llc_index, &eax, &ebx, &ecx, &edx);
                if (eax)
                        num_sharing_cache = ((eax >> 14) & 0xfff) + 1;

                if (num_sharing_cache) {
                        int bits = get_count_order(num_sharing_cache);

                        per_cpu(cpu_llc_id, cpu) = c->apicid >> bits;
                }
        }
}

void cacheinfo_hygon_init_llc_id(struct cpuinfo_x86 *c, int cpu, u8 node_id)
{
        /*
         * We may have multiple LLCs if L3 caches exist, so check if we
         * have an L3 cache by looking at the L3 cache CPUID leaf.
         */
        if (!cpuid_edx(0x80000006))
                return;

        /*
         * LLC is at the core complex level.
         * Core complex ID is ApicId[3] for these processors.
         */
        per_cpu(cpu_llc_id, cpu) = c->apicid >> 3;
}

void init_amd_cacheinfo(struct cpuinfo_x86 *c)
{

        if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
                num_cache_leaves = find_num_cache_leaves(c);
        } else if (c->extended_cpuid_level >= 0x80000006) {
                if (cpuid_edx(0x80000006) & 0xf000)
                        num_cache_leaves = 4;
                else
                        num_cache_leaves = 3;
        }
}

void init_hygon_cacheinfo(struct cpuinfo_x86 *c)
{
        num_cache_leaves = find_num_cache_leaves(c);
}

void init_intel_cacheinfo(struct cpuinfo_x86 *c)
{
        /* Cache sizes */
        unsigned int trace = 0, l1i = 0, l1d = 0, l2 = 0, l3 = 0;
        unsigned int new_l1d = 0, new_l1i = 0; /* Cache sizes from cpuid(4) */
        unsigned int new_l2 = 0, new_l3 = 0, i; /* Cache sizes from cpuid(4) */
        unsigned int l2_id = 0, l3_id = 0, num_threads_sharing, index_msb;
#ifdef CONFIG_SMP
        unsigned int cpu = c->cpu_index;
#endif

        if (c->cpuid_level > 3) {
                static int is_initialized;

                if (is_initialized == 0) {
                        /* Init num_cache_leaves from boot CPU */
                        num_cache_leaves = find_num_cache_leaves(c);
                        is_initialized++;
                }

                /*
                 * Whenever possible use cpuid(4), deterministic cache
                 * parameters cpuid leaf to find the cache details
                 */
                for (i = 0; i < num_cache_leaves; i++) {
                        struct _cpuid4_info_regs this_leaf = {};
                        int retval;

                        retval = cpuid4_cache_lookup_regs(i, &this_leaf);
                        if (retval < 0)
                                continue;

                        switch (this_leaf.eax.split.level) {
                        case 1:
                                if (this_leaf.eax.split.type == CTYPE_DATA)
                                        new_l1d = this_leaf.size/1024;
                                else if (this_leaf.eax.split.type == CTYPE_INST)
                                        new_l1i = this_leaf.size/1024;
                                break;
                        case 2:
                                new_l2 = this_leaf.size/1024;
                                num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
                                index_msb = get_count_order(num_threads_sharing);
                                l2_id = c->apicid & ~((1 << index_msb) - 1);
                                break;
                        case 3:
                                new_l3 = this_leaf.size/1024;
                                num_threads_sharing = 1 + this_leaf.eax.split.num_threads_sharing;
                                index_msb = get_count_order(num_threads_sharing);
                                l3_id = c->apicid & ~((1 << index_msb) - 1);
                                break;
                        default:
                                break;
                        }
                }
        }
        /*
         * Don't use cpuid2 if cpuid4 is supported. For P4, we use cpuid2 for
         * trace cache
         */
        if ((num_cache_leaves == 0 || c->x86 == 15) && c->cpuid_level > 1) {
                /* supports eax=2  call */
                int j, n;
                unsigned int regs[4];
                unsigned char *dp = (unsigned char *)regs;
                int only_trace = 0;

                if (num_cache_leaves != 0 && c->x86 == 15)
                        only_trace = 1;

                /* Number of times to iterate */
                n = cpuid_eax(2) & 0xFF;

                for (i = 0 ; i < n ; i++) {
                        cpuid(2, &regs[0], &regs[1], &regs[2], &regs[3]);

                        /* If bit 31 is set, this is an unknown format */
                        for (j = 0 ; j < 3 ; j++)
                                if (regs[j] & (1 << 31))
                                        regs[j] = 0;

                        /* Byte 0 is level count, not a descriptor */
                        for (j = 1 ; j < 16 ; j++) {
                                unsigned char des = dp[j];
                                unsigned char k = 0;

                                /* look up this descriptor in the table */
                                while (cache_table[k].descriptor != 0) {
                                        if (cache_table[k].descriptor == des) {
                                                if (only_trace && cache_table[k].cache_type != LVL_TRACE)
                                                        break;
                                                switch (cache_table[k].cache_type) {
                                                case LVL_1_INST:
                                                        l1i += cache_table[k].size;
                                                        break;
                                                case LVL_1_DATA:
                                                        l1d += cache_table[k].size;
                                                        break;
                                                case LVL_2:
                                                        l2 += cache_table[k].size;
                                                        break;
                                                case LVL_3:
                                                        l3 += cache_table[k].size;
                                                        break;
                                                case LVL_TRACE:
                                                        trace += cache_table[k].size;
                                                        break;
                                                }

                                                break;
                                        }

                                        k++;
                                }
                        }
                }
        }

        if (new_l1d)
                l1d = new_l1d;

        if (new_l1i)
                l1i = new_l1i;

        if (new_l2) {
                l2 = new_l2;
#ifdef CONFIG_SMP
                per_cpu(cpu_llc_id, cpu) = l2_id;
#endif
        }

        if (new_l3) {
                l3 = new_l3;
#ifdef CONFIG_SMP
                per_cpu(cpu_llc_id, cpu) = l3_id;
#endif
        }

#ifdef CONFIG_SMP
        /*
         * If cpu_llc_id is not yet set, this means cpuid_level < 4 which in
         * turns means that the only possibility is SMT (as indicated in
         * cpuid1). Since cpuid2 doesn't specify shared caches, and we know
         * that SMT shares all caches, we can unconditionally set cpu_llc_id to
         * c->phys_proc_id.
         */
        if (per_cpu(cpu_llc_id, cpu) == BAD_APICID)
                per_cpu(cpu_llc_id, cpu) = c->phys_proc_id;
#endif

        c->x86_cache_size = l3 ? l3 : (l2 ? l2 : (l1i+l1d));

        if (!l2)
                cpu_detect_cache_sizes(c);
}

static int __cache_amd_cpumap_setup(unsigned int cpu, int index,
                                    struct _cpuid4_info_regs *base)
{
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
        struct cacheinfo *this_leaf;
        int i, sibling;

        /*
         * For L3, always use the pre-calculated cpu_llc_shared_mask
         * to derive shared_cpu_map.
         */
        if (index == 3) {
                for_each_cpu(i, cpu_llc_shared_mask(cpu)) {
                        this_cpu_ci = get_cpu_cacheinfo(i);
                        if (!this_cpu_ci->info_list)
                                continue;
                        this_leaf = this_cpu_ci->info_list + index;
                        for_each_cpu(sibling, cpu_llc_shared_mask(cpu)) {
                                if (!cpu_online(sibling))
                                        continue;
                                cpumask_set_cpu(sibling,
                                                &this_leaf->shared_cpu_map);
                        }
                }
        } else if (boot_cpu_has(X86_FEATURE_TOPOEXT)) {
                unsigned int apicid, nshared, first, last;

                nshared = base->eax.split.num_threads_sharing + 1;
                apicid = cpu_data(cpu).apicid;
                first = apicid - (apicid % nshared);
                last = first + nshared - 1;

                for_each_online_cpu(i) {
                        this_cpu_ci = get_cpu_cacheinfo(i);
                        if (!this_cpu_ci->info_list)
                                continue;

                        apicid = cpu_data(i).apicid;
                        if ((apicid < first) || (apicid > last))
                                continue;

                        this_leaf = this_cpu_ci->info_list + index;

                        for_each_online_cpu(sibling) {
                                apicid = cpu_data(sibling).apicid;
                                if ((apicid < first) || (apicid > last))
                                        continue;
                                cpumask_set_cpu(sibling,
                                                &this_leaf->shared_cpu_map);
                        }
                }
        } else
                return 0;

        return 1;
}

static void __cache_cpumap_setup(unsigned int cpu, int index,
                                 struct _cpuid4_info_regs *base)
{
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
        struct cacheinfo *this_leaf, *sibling_leaf;
        unsigned long num_threads_sharing;
        int index_msb, i;
        struct cpuinfo_x86 *c = &cpu_data(cpu);

        if (c->x86_vendor == X86_VENDOR_AMD ||
            c->x86_vendor == X86_VENDOR_HYGON) {
                if (__cache_amd_cpumap_setup(cpu, index, base))
                        return;
        }

        this_leaf = this_cpu_ci->info_list + index;
        num_threads_sharing = 1 + base->eax.split.num_threads_sharing;

        cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map);
        if (num_threads_sharing == 1)
                return;

        index_msb = get_count_order(num_threads_sharing);

        for_each_online_cpu(i)
                if (cpu_data(i).apicid >> index_msb == c->apicid >> index_msb) {
                        struct cpu_cacheinfo *sib_cpu_ci = get_cpu_cacheinfo(i);

                        if (i == cpu || !sib_cpu_ci->info_list)
                                continue;/* skip if itself or no cacheinfo */
                        sibling_leaf = sib_cpu_ci->info_list + index;
                        cpumask_set_cpu(i, &this_leaf->shared_cpu_map);
                        cpumask_set_cpu(cpu, &sibling_leaf->shared_cpu_map);
                }
}

static void ci_leaf_init(struct cacheinfo *this_leaf,
                         struct _cpuid4_info_regs *base)
{
        this_leaf->id = base->id;
        this_leaf->attributes = CACHE_ID;
        this_leaf->level = base->eax.split.level;
        this_leaf->type = cache_type_map[base->eax.split.type];
        this_leaf->coherency_line_size =
                                base->ebx.split.coherency_line_size + 1;
        this_leaf->ways_of_associativity =
                                base->ebx.split.ways_of_associativity + 1;
        this_leaf->size = base->size;
        this_leaf->number_of_sets = base->ecx.split.number_of_sets + 1;
        this_leaf->physical_line_partition =
                                base->ebx.split.physical_line_partition + 1;
        this_leaf->priv = base->nb;
}

static int __init_cache_level(unsigned int cpu)
{
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);

        if (!num_cache_leaves)
                return -ENOENT;
        if (!this_cpu_ci)
                return -EINVAL;
        this_cpu_ci->num_levels = 3;
        this_cpu_ci->num_leaves = num_cache_leaves;
        return 0;
}

/*
 * The max shared threads number comes from CPUID.4:EAX[25-14] with input
 * ECX as cache index. Then right shift apicid by the number's order to get
 * cache id for this cache node.
 */
static void get_cache_id(int cpu, struct _cpuid4_info_regs *id4_regs)
{
        struct cpuinfo_x86 *c = &cpu_data(cpu);
        unsigned long num_threads_sharing;
        int index_msb;

        num_threads_sharing = 1 + id4_regs->eax.split.num_threads_sharing;
        index_msb = get_count_order(num_threads_sharing);
        id4_regs->id = c->apicid >> index_msb;
}

static int __populate_cache_leaves(unsigned int cpu)
{
        unsigned int idx, ret;
        struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu);
        struct cacheinfo *this_leaf = this_cpu_ci->info_list;
        struct _cpuid4_info_regs id4_regs = {};

        for (idx = 0; idx < this_cpu_ci->num_leaves; idx++) {
                ret = cpuid4_cache_lookup_regs(idx, &id4_regs);
                if (ret)
                        return ret;
                get_cache_id(cpu, &id4_regs);
                ci_leaf_init(this_leaf++, &id4_regs);
                __cache_cpumap_setup(cpu, idx, &id4_regs);
        }
        this_cpu_ci->cpu_map_populated = true;

        return 0;
}

DEFINE_SMP_CALL_CACHE_FUNCTION(init_cache_level)
DEFINE_SMP_CALL_CACHE_FUNCTION(populate_cache_leaves)