i386: move kernel/cpu

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 806 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/intel_cacheinfo.c b/arch/x86/kernel/cpu/intel_cacheinfo.c
new file mode 100644
index 000000000000..db6c25aa5776
--- /dev/null
+++ b/arch/x86/kernel/cpu/intel_cacheinfo.c
@@ -0,0 +1,806 @@
+/*
+ *      Routines to indentify 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/init.h>
+#include <linux/slab.h>
+#include <linux/device.h>
+#include <linux/compiler.h>
+#include <linux/cpu.h>
+#include <linux/sched.h>
+
+#include <asm/processor.h>
+#include <asm/smp.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;
+};
+
+/* all the cache descriptor types we care about (no TLB or trace cache entries) */
+static struct _cache_table cache_table[] __cpuinitdata =
+{
+	{ 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 */
+	{ 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 */
+	{ 0x22, LVL_3,      512 },	/* 4-way set assoc, sectored cache, 64 byte line size */
+	{ 0x23, LVL_3,      1024 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x25, LVL_3,      2048 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x29, LVL_3,      4096 },	/* 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 */
+	{ 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,      1024 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x45, LVL_2,      2048 },	/* 4-way set assoc, 32 byte line size */
+	{ 0x46, LVL_3,      4096 },	/* 4-way set assoc, 64 byte line size */
+	{ 0x47, LVL_3,      8192 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x49, LVL_3,      4096 },	/* 16-way set assoc, 64 byte line size */
+	{ 0x4a, LVL_3,      6144 },	/* 12-way set assoc, 64 byte line size */
+	{ 0x4b, LVL_3,      8192 },	/* 16-way set assoc, 64 byte line size */
+	{ 0x4c, LVL_3,     12288 },	/* 12-way set assoc, 64 byte line size */
+	{ 0x4d, LVL_3,     16384 },	/* 16-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,    1024 },	/* 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,    1024 },	/* 8-way set assoc, sectored cache, 64 byte line size */
+	{ 0x7d, LVL_2,    2048 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x7f, LVL_2,     512 },	/* 2-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,    1024 },	/* 8-way set assoc, 32 byte line size */
+	{ 0x85, LVL_2,    2048 },	/* 8-way set assoc, 32 byte line size */
+	{ 0x86, LVL_2,     512 },	/* 4-way set assoc, 64 byte line size */
+	{ 0x87, LVL_2,    1024 },	/* 8-way set assoc, 64 byte line size */
+	{ 0x00, 0, 0}
+};
+
+
+enum _cache_type
+{
+	CACHE_TYPE_NULL	= 0,
+	CACHE_TYPE_DATA = 1,
+	CACHE_TYPE_INST = 2,
+	CACHE_TYPE_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 {
+	union _cpuid4_leaf_eax eax;
+	union _cpuid4_leaf_ebx ebx;
+	union _cpuid4_leaf_ecx ecx;
+	unsigned long size;
+	cpumask_t shared_cpu_map;
+};
+
+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,
+	[0xf] = 0xffff // ??
+};
+
+static const unsigned char levels[] = { 1, 1, 2, 3 };
+static const unsigned char types[] = { 1, 2, 3, 3 };
+
+static void __cpuinit 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;
+	case 0:
+		if (!l1->val)
+			return;
+		assoc = 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 = 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 = current_cpu_data.x86_cache_size;
+		break;
+	case 3:
+		if (!l3.val)
+			return;
+		assoc = l3.assoc;
+		line_size = l3.line_size;
+		lines_per_tag = l3.lines_per_tag;
+		size_in_kb = l3.size_encoded * 512;
+		break;
+	default:
+		return;
+	}
+
+	eax->split.is_self_initializing = 1;
+	eax->split.type = types[leaf];
+	eax->split.level = levels[leaf];
+	if (leaf == 3)
+		eax->split.num_threads_sharing = current_cpu_data.x86_max_cores - 1;
+	else
+		eax->split.num_threads_sharing = 0;
+	eax->split.num_cores_on_die = current_cpu_data.x86_max_cores - 1;
+
+
+	if (assoc == 0xf)
+		eax->split.is_fully_associative = 1;
+	ebx->split.coherency_line_size = line_size - 1;
+	ebx->split.ways_of_associativity = assocs[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;
+}
+
+static int __cpuinit cpuid4_cache_lookup(int index, struct _cpuid4_info *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)
+		amd_cpuid4(index, &eax, &ebx, &ecx);
+	else
+		cpuid_count(4, index, &eax.full, &ebx.full, &ecx.full,  &edx);
+	if (eax.split.type == CACHE_TYPE_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 __cpuinit find_num_cache_leaves(void)
+{
+	unsigned int		eax, ebx, ecx, edx;
+	union _cpuid4_leaf_eax	cache_eax;
+	int 			i = -1;
+
+	do {
+		++i;
+		/* Do cpuid(4) loop to find out num_cache_leaves */
+		cpuid_count(4, i, &eax, &ebx, &ecx, &edx);
+		cache_eax.full = eax;
+	} while (cache_eax.split.type != CACHE_TYPE_NULL);
+	return i;
+}
+
+unsigned int __cpuinit init_intel_cacheinfo(struct cpuinfo_x86 *c)
+{
+	unsigned int trace = 0, l1i = 0, l1d = 0, l2 = 0, l3 = 0; /* Cache sizes */
+	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_X86_HT
+	unsigned int cpu = (c == &boot_cpu_data) ? 0 : (c - cpu_data);
+#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();
+			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 this_leaf;
+
+			int retval;
+
+			retval = cpuid4_cache_lookup(i, &this_leaf);
+			if (retval >= 0) {
+				switch(this_leaf.eax.split.level) {
+				    case 1:
+					if (this_leaf.eax.split.type ==
+							CACHE_TYPE_DATA)
+						new_l1d = this_leaf.size/1024;
+					else if (this_leaf.eax.split.type ==
+							CACHE_TYPE_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 >> index_msb;
+					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 >> index_msb;
+					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 i, j, n;
+		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] < 0 ) 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_X86_HT
+		cpu_llc_id[cpu] = l2_id;
+#endif
+	}
+
+	if (new_l3) {
+		l3 = new_l3;
+#ifdef CONFIG_X86_HT
+		cpu_llc_id[cpu] = l3_id;
+#endif
+	}
+
+	if (trace)
+		printk (KERN_INFO "CPU: Trace cache: %dK uops", trace);
+	else if ( l1i )
+		printk (KERN_INFO "CPU: L1 I cache: %dK", l1i);
+
+	if (l1d)
+		printk(", L1 D cache: %dK\n", l1d);
+	else
+		printk("\n");
+
+	if (l2)
+		printk(KERN_INFO "CPU: L2 cache: %dK\n", l2);
+
+	if (l3)
+		printk(KERN_INFO "CPU: L3 cache: %dK\n", l3);
+
+	c->x86_cache_size = l3 ? l3 : (l2 ? l2 : (l1i+l1d));
+
+	return l2;
+}
+
+/* pointer to _cpuid4_info array (for each cache leaf) */
+static struct _cpuid4_info *cpuid4_info[NR_CPUS];
+#define CPUID4_INFO_IDX(x,y)    (&((cpuid4_info[x])[y]))
+
+#ifdef CONFIG_SMP
+static void __cpuinit cache_shared_cpu_map_setup(unsigned int cpu, int index)
+{
+	struct _cpuid4_info	*this_leaf, *sibling_leaf;
+	unsigned long num_threads_sharing;
+	int index_msb, i;
+	struct cpuinfo_x86 *c = cpu_data;
+
+	this_leaf = CPUID4_INFO_IDX(cpu, index);
+	num_threads_sharing = 1 + this_leaf->eax.split.num_threads_sharing;
+
+	if (num_threads_sharing == 1)
+		cpu_set(cpu, this_leaf->shared_cpu_map);
+	else {
+		index_msb = get_count_order(num_threads_sharing);
+
+		for_each_online_cpu(i) {
+			if (c[i].apicid >> index_msb ==
+			    c[cpu].apicid >> index_msb) {
+				cpu_set(i, this_leaf->shared_cpu_map);
+				if (i != cpu && cpuid4_info[i])  {
+					sibling_leaf = CPUID4_INFO_IDX(i, index);
+					cpu_set(cpu, sibling_leaf->shared_cpu_map);
+				}
+			}
+		}
+	}
+}
+static void __cpuinit cache_remove_shared_cpu_map(unsigned int cpu, int index)
+{
+	struct _cpuid4_info	*this_leaf, *sibling_leaf;
+	int sibling;
+
+	this_leaf = CPUID4_INFO_IDX(cpu, index);
+	for_each_cpu_mask(sibling, this_leaf->shared_cpu_map) {
+		sibling_leaf = CPUID4_INFO_IDX(sibling, index);	
+		cpu_clear(cpu, sibling_leaf->shared_cpu_map);
+	}
+}
+#else
+static void __init cache_shared_cpu_map_setup(unsigned int cpu, int index) {}
+static void __init cache_remove_shared_cpu_map(unsigned int cpu, int index) {}
+#endif
+
+static void free_cache_attributes(unsigned int cpu)
+{
+	kfree(cpuid4_info[cpu]);
+	cpuid4_info[cpu] = NULL;
+}
+
+static int __cpuinit detect_cache_attributes(unsigned int cpu)
+{
+	struct _cpuid4_info	*this_leaf;
+	unsigned long 		j;
+	int 			retval;
+	cpumask_t		oldmask;
+
+	if (num_cache_leaves == 0)
+		return -ENOENT;
+
+	cpuid4_info[cpu] = kzalloc(
+	    sizeof(struct _cpuid4_info) * num_cache_leaves, GFP_KERNEL);
+	if (cpuid4_info[cpu] == NULL)
+		return -ENOMEM;
+
+	oldmask = current->cpus_allowed;
+	retval = set_cpus_allowed(current, cpumask_of_cpu(cpu));
+	if (retval)
+		goto out;
+
+	/* Do cpuid and store the results */
+	retval = 0;
+	for (j = 0; j < num_cache_leaves; j++) {
+		this_leaf = CPUID4_INFO_IDX(cpu, j);
+		retval = cpuid4_cache_lookup(j, this_leaf);
+		if (unlikely(retval < 0))
+			break;
+		cache_shared_cpu_map_setup(cpu, j);
+	}
+	set_cpus_allowed(current, oldmask);
+
+out:
+	if (retval)
+		free_cache_attributes(cpu);
+	return retval;
+}
+
+#ifdef CONFIG_SYSFS
+
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+
+extern struct sysdev_class cpu_sysdev_class; /* from drivers/base/cpu.c */
+
+/* pointer to kobject for cpuX/cache */
+static struct kobject * cache_kobject[NR_CPUS];
+
+struct _index_kobject {
+	struct kobject kobj;
+	unsigned int cpu;
+	unsigned short index;
+};
+
+/* pointer to array of kobjects for cpuX/cache/indexY */
+static struct _index_kobject *index_kobject[NR_CPUS];
+#define INDEX_KOBJECT_PTR(x,y)    (&((index_kobject[x])[y]))
+
+#define show_one_plus(file_name, object, val)				\
+static ssize_t show_##file_name						\
+			(struct _cpuid4_info *this_leaf, char *buf)	\
+{									\
+	return sprintf (buf, "%lu\n", (unsigned long)this_leaf->object + val); \
+}
+
+show_one_plus(level, eax.split.level, 0);
+show_one_plus(coherency_line_size, ebx.split.coherency_line_size, 1);
+show_one_plus(physical_line_partition, ebx.split.physical_line_partition, 1);
+show_one_plus(ways_of_associativity, ebx.split.ways_of_associativity, 1);
+show_one_plus(number_of_sets, ecx.split.number_of_sets, 1);
+
+static ssize_t show_size(struct _cpuid4_info *this_leaf, char *buf)
+{
+	return sprintf (buf, "%luK\n", this_leaf->size / 1024);
+}
+
+static ssize_t show_shared_cpu_map(struct _cpuid4_info *this_leaf, char *buf)
+{
+	char mask_str[NR_CPUS];
+	cpumask_scnprintf(mask_str, NR_CPUS, this_leaf->shared_cpu_map);
+	return sprintf(buf, "%s\n", mask_str);
+}
+
+static ssize_t show_type(struct _cpuid4_info *this_leaf, char *buf) {
+	switch(this_leaf->eax.split.type) {
+	    case CACHE_TYPE_DATA:
+		return sprintf(buf, "Data\n");
+		break;
+	    case CACHE_TYPE_INST:
+		return sprintf(buf, "Instruction\n");
+		break;
+	    case CACHE_TYPE_UNIFIED:
+		return sprintf(buf, "Unified\n");
+		break;
+	    default:
+		return sprintf(buf, "Unknown\n");
+		break;
+	}
+}
+
+struct _cache_attr {
+	struct attribute attr;
+	ssize_t (*show)(struct _cpuid4_info *, char *);
+	ssize_t (*store)(struct _cpuid4_info *, const char *, size_t count);
+};
+
+#define define_one_ro(_name) \
+static struct _cache_attr _name = \
+	__ATTR(_name, 0444, show_##_name, NULL)
+
+define_one_ro(level);
+define_one_ro(type);
+define_one_ro(coherency_line_size);
+define_one_ro(physical_line_partition);
+define_one_ro(ways_of_associativity);
+define_one_ro(number_of_sets);
+define_one_ro(size);
+define_one_ro(shared_cpu_map);
+
+static struct attribute * default_attrs[] = {
+	&type.attr,
+	&level.attr,
+	&coherency_line_size.attr,
+	&physical_line_partition.attr,
+	&ways_of_associativity.attr,
+	&number_of_sets.attr,
+	&size.attr,
+	&shared_cpu_map.attr,
+	NULL
+};
+
+#define to_object(k) container_of(k, struct _index_kobject, kobj)
+#define to_attr(a) container_of(a, struct _cache_attr, attr)
+
+static ssize_t show(struct kobject * kobj, struct attribute * attr, char * buf)
+{
+	struct _cache_attr *fattr = to_attr(attr);
+	struct _index_kobject *this_leaf = to_object(kobj);
+	ssize_t ret;
+
+	ret = fattr->show ?
+		fattr->show(CPUID4_INFO_IDX(this_leaf->cpu, this_leaf->index),
+			buf) :
+	       	0;
+	return ret;
+}
+
+static ssize_t store(struct kobject * kobj, struct attribute * attr,
+		     const char * buf, size_t count)
+{
+	return 0;
+}
+
+static struct sysfs_ops sysfs_ops = {
+	.show   = show,
+	.store  = store,
+};
+
+static struct kobj_type ktype_cache = {
+	.sysfs_ops	= &sysfs_ops,
+	.default_attrs	= default_attrs,
+};
+
+static struct kobj_type ktype_percpu_entry = {
+	.sysfs_ops	= &sysfs_ops,
+};
+
+static void cpuid4_cache_sysfs_exit(unsigned int cpu)
+{
+	kfree(cache_kobject[cpu]);
+	kfree(index_kobject[cpu]);
+	cache_kobject[cpu] = NULL;
+	index_kobject[cpu] = NULL;
+	free_cache_attributes(cpu);
+}
+
+static int __cpuinit cpuid4_cache_sysfs_init(unsigned int cpu)
+{
+
+	if (num_cache_leaves == 0)
+		return -ENOENT;
+
+	detect_cache_attributes(cpu);
+	if (cpuid4_info[cpu] == NULL)
+		return -ENOENT;
+
+	/* Allocate all required memory */
+	cache_kobject[cpu] = kzalloc(sizeof(struct kobject), GFP_KERNEL);
+	if (unlikely(cache_kobject[cpu] == NULL))
+		goto err_out;
+
+	index_kobject[cpu] = kzalloc(
+	    sizeof(struct _index_kobject ) * num_cache_leaves, GFP_KERNEL);
+	if (unlikely(index_kobject[cpu] == NULL))
+		goto err_out;
+
+	return 0;
+
+err_out:
+	cpuid4_cache_sysfs_exit(cpu);
+	return -ENOMEM;
+}
+
+/* Add/Remove cache interface for CPU device */
+static int __cpuinit cache_add_dev(struct sys_device * sys_dev)
+{
+	unsigned int cpu = sys_dev->id;
+	unsigned long i, j;
+	struct _index_kobject *this_object;
+	int retval = 0;
+
+	retval = cpuid4_cache_sysfs_init(cpu);
+	if (unlikely(retval < 0))
+		return retval;
+
+	cache_kobject[cpu]->parent = &sys_dev->kobj;
+	kobject_set_name(cache_kobject[cpu], "%s", "cache");
+	cache_kobject[cpu]->ktype = &ktype_percpu_entry;
+	retval = kobject_register(cache_kobject[cpu]);
+
+	for (i = 0; i < num_cache_leaves; i++) {
+		this_object = INDEX_KOBJECT_PTR(cpu,i);
+		this_object->cpu = cpu;
+		this_object->index = i;
+		this_object->kobj.parent = cache_kobject[cpu];
+		kobject_set_name(&(this_object->kobj), "index%1lu", i);
+		this_object->kobj.ktype = &ktype_cache;
+		retval = kobject_register(&(this_object->kobj));
+		if (unlikely(retval)) {
+			for (j = 0; j < i; j++) {
+				kobject_unregister(
+					&(INDEX_KOBJECT_PTR(cpu,j)->kobj));
+			}
+			kobject_unregister(cache_kobject[cpu]);
+			cpuid4_cache_sysfs_exit(cpu);
+			break;
+		}
+	}
+	return retval;
+}
+
+static void __cpuinit cache_remove_dev(struct sys_device * sys_dev)
+{
+	unsigned int cpu = sys_dev->id;
+	unsigned long i;
+
+	if (cpuid4_info[cpu] == NULL)
+		return;
+	for (i = 0; i < num_cache_leaves; i++) {
+		cache_remove_shared_cpu_map(cpu, i);
+		kobject_unregister(&(INDEX_KOBJECT_PTR(cpu,i)->kobj));
+	}
+	kobject_unregister(cache_kobject[cpu]);
+	cpuid4_cache_sysfs_exit(cpu);
+	return;
+}
+
+static int __cpuinit cacheinfo_cpu_callback(struct notifier_block *nfb,
+					unsigned long action, void *hcpu)
+{
+	unsigned int cpu = (unsigned long)hcpu;
+	struct sys_device *sys_dev;
+
+	sys_dev = get_cpu_sysdev(cpu);
+	switch (action) {
+	case CPU_ONLINE:
+	case CPU_ONLINE_FROZEN:
+		cache_add_dev(sys_dev);
+		break;
+	case CPU_DEAD:
+	case CPU_DEAD_FROZEN:
+		cache_remove_dev(sys_dev);
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block __cpuinitdata cacheinfo_cpu_notifier =
+{
+    .notifier_call = cacheinfo_cpu_callback,
+};
+
+static int __cpuinit cache_sysfs_init(void)
+{
+	int i;
+
+	if (num_cache_leaves == 0)
+		return 0;
+
+	register_hotcpu_notifier(&cacheinfo_cpu_notifier);
+
+	for_each_online_cpu(i) {
+		cacheinfo_cpu_callback(&cacheinfo_cpu_notifier, CPU_ONLINE,
+			(void *)(long)i);
+	}
+
+	return 0;
+}
+
+device_initcall(cache_sysfs_init);
+
+#endif