common.c 28.5 KB
Newer Older
L
Linus Torvalds 已提交
1
#include <linux/init.h>
2 3
#include <linux/kernel.h>
#include <linux/sched.h>
L
Linus Torvalds 已提交
4
#include <linux/string.h>
5 6 7 8 9
#include <linux/bootmem.h>
#include <linux/bitops.h>
#include <linux/module.h>
#include <linux/kgdb.h>
#include <linux/topology.h>
L
Linus Torvalds 已提交
10 11 12 13 14 15
#include <linux/delay.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <asm/i387.h>
#include <asm/msr.h>
#include <asm/io.h>
16
#include <asm/linkage.h>
L
Linus Torvalds 已提交
17
#include <asm/mmu_context.h>
18
#include <asm/mtrr.h>
19
#include <asm/mce.h>
20
#include <asm/pat.h>
21
#include <asm/asm.h>
22
#include <asm/numa.h>
I
Ingo Molnar 已提交
23
#include <asm/smp.h>
24
#include <asm/cpu.h>
25
#include <asm/cpumask.h>
I
Ingo Molnar 已提交
26
#include <asm/apic.h>
27 28

#ifdef CONFIG_X86_LOCAL_APIC
T
Tejun Heo 已提交
29
#include <asm/uv/uv.h>
L
Linus Torvalds 已提交
30 31
#endif

32 33 34 35 36 37 38
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/desc.h>
#include <asm/atomic.h>
#include <asm/proto.h>
#include <asm/sections.h>
#include <asm/setup.h>
39
#include <asm/hypervisor.h>
40
#include <asm/stackprotector.h>
41

L
Linus Torvalds 已提交
42 43
#include "cpu.h"

44 45 46 47 48 49 50 51 52 53
#ifdef CONFIG_X86_64

/* all of these masks are initialized in setup_cpu_local_masks() */
cpumask_var_t cpu_callin_mask;
cpumask_var_t cpu_callout_mask;
cpumask_var_t cpu_initialized_mask;

/* representing cpus for which sibling maps can be computed */
cpumask_var_t cpu_sibling_setup_mask;

B
Brian Gerst 已提交
54
/* correctly size the local cpu masks */
55
void __init setup_cpu_local_masks(void)
B
Brian Gerst 已提交
56 57 58 59 60 61 62
{
	alloc_bootmem_cpumask_var(&cpu_initialized_mask);
	alloc_bootmem_cpumask_var(&cpu_callin_mask);
	alloc_bootmem_cpumask_var(&cpu_callout_mask);
	alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
}

63 64 65 66 67 68 69 70 71 72
#else /* CONFIG_X86_32 */

cpumask_t cpu_callin_map;
cpumask_t cpu_callout_map;
cpumask_t cpu_initialized;
cpumask_t cpu_sibling_setup_map;

#endif /* CONFIG_X86_32 */


73 74
static struct cpu_dev *this_cpu __cpuinitdata;

B
Brian Gerst 已提交
75
DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
Y
Yinghai Lu 已提交
76
#ifdef CONFIG_X86_64
B
Brian Gerst 已提交
77 78 79 80 81 82 83 84
	/*
	 * We need valid kernel segments for data and code in long mode too
	 * IRET will check the segment types  kkeil 2000/10/28
	 * Also sysret mandates a special GDT layout
	 *
	 * The TLS descriptors are currently at a different place compared to i386.
	 * Hopefully nobody expects them at a fixed place (Wine?)
	 */
Y
Yinghai Lu 已提交
85 86 87 88 89 90 91
	[GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
	[GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
#else
92 93 94 95
	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00cf9a00 } } },
	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9200 } } },
	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00cffa00 } } },
	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff200 } } },
96 97 98 99 100
	/*
	 * Segments used for calling PnP BIOS have byte granularity.
	 * They code segments and data segments have fixed 64k limits,
	 * the transfer segment sizes are set at run time.
	 */
101 102 103 104 105 106 107 108 109 110
	/* 32-bit code */
	[GDT_ENTRY_PNPBIOS_CS32] = { { { 0x0000ffff, 0x00409a00 } } },
	/* 16-bit code */
	[GDT_ENTRY_PNPBIOS_CS16] = { { { 0x0000ffff, 0x00009a00 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_DS] = { { { 0x0000ffff, 0x00009200 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_TS1] = { { { 0x00000000, 0x00009200 } } },
	/* 16-bit data */
	[GDT_ENTRY_PNPBIOS_TS2] = { { { 0x00000000, 0x00009200 } } },
111 112 113 114
	/*
	 * The APM segments have byte granularity and their bases
	 * are set at run time.  All have 64k limits.
	 */
115 116
	/* 32-bit code */
	[GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
117
	/* 16-bit code */
118 119 120
	[GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
	/* data */
	[GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
121

122
	[GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
123
	[GDT_ENTRY_PERCPU] = { { { 0x0000ffff, 0x00cf9200 } } },
124
	GDT_STACK_CANARY_INIT
Y
Yinghai Lu 已提交
125
#endif
B
Brian Gerst 已提交
126
} };
127
EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
128

129
#ifdef CONFIG_X86_32
130 131
static int cachesize_override __cpuinitdata = -1;
static int disable_x86_serial_nr __cpuinitdata = 1;
L
Linus Torvalds 已提交
132

133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159
static int __init cachesize_setup(char *str)
{
	get_option(&str, &cachesize_override);
	return 1;
}
__setup("cachesize=", cachesize_setup);

static int __init x86_fxsr_setup(char *s)
{
	setup_clear_cpu_cap(X86_FEATURE_FXSR);
	setup_clear_cpu_cap(X86_FEATURE_XMM);
	return 1;
}
__setup("nofxsr", x86_fxsr_setup);

static int __init x86_sep_setup(char *s)
{
	setup_clear_cpu_cap(X86_FEATURE_SEP);
	return 1;
}
__setup("nosep", x86_sep_setup);

/* Standard macro to see if a specific flag is changeable */
static inline int flag_is_changeable_p(u32 flag)
{
	u32 f1, f2;

160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178
	/*
	 * Cyrix and IDT cpus allow disabling of CPUID
	 * so the code below may return different results
	 * when it is executed before and after enabling
	 * the CPUID. Add "volatile" to not allow gcc to
	 * optimize the subsequent calls to this function.
	 */
	asm volatile ("pushfl\n\t"
		      "pushfl\n\t"
		      "popl %0\n\t"
		      "movl %0,%1\n\t"
		      "xorl %2,%0\n\t"
		      "pushl %0\n\t"
		      "popfl\n\t"
		      "pushfl\n\t"
		      "popl %0\n\t"
		      "popfl\n\t"
		      : "=&r" (f1), "=&r" (f2)
		      : "ir" (flag));
179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210

	return ((f1^f2) & flag) != 0;
}

/* Probe for the CPUID instruction */
static int __cpuinit have_cpuid_p(void)
{
	return flag_is_changeable_p(X86_EFLAGS_ID);
}

static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
	if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr) {
		/* Disable processor serial number */
		unsigned long lo, hi;
		rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
		lo |= 0x200000;
		wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
		printk(KERN_NOTICE "CPU serial number disabled.\n");
		clear_cpu_cap(c, X86_FEATURE_PN);

		/* Disabling the serial number may affect the cpuid level */
		c->cpuid_level = cpuid_eax(0);
	}
}

static int __init x86_serial_nr_setup(char *s)
{
	disable_x86_serial_nr = 0;
	return 1;
}
__setup("serialnumber", x86_serial_nr_setup);
211
#else
212 213 214 215
static inline int flag_is_changeable_p(u32 flag)
{
	return 1;
}
216 217 218 219 220
/* Probe for the CPUID instruction */
static inline int have_cpuid_p(void)
{
	return 1;
}
221 222 223
static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
{
}
224
#endif
225

226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254
/*
 * Some CPU features depend on higher CPUID levels, which may not always
 * be available due to CPUID level capping or broken virtualization
 * software.  Add those features to this table to auto-disable them.
 */
struct cpuid_dependent_feature {
	u32 feature;
	u32 level;
};
static const struct cpuid_dependent_feature __cpuinitconst
cpuid_dependent_features[] = {
	{ X86_FEATURE_MWAIT,		0x00000005 },
	{ X86_FEATURE_DCA,		0x00000009 },
	{ X86_FEATURE_XSAVE,		0x0000000d },
	{ 0, 0 }
};

static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
{
	const struct cpuid_dependent_feature *df;
	for (df = cpuid_dependent_features; df->feature; df++) {
		/*
		 * Note: cpuid_level is set to -1 if unavailable, but
		 * extended_extended_level is set to 0 if unavailable
		 * and the legitimate extended levels are all negative
		 * when signed; hence the weird messing around with
		 * signs here...
		 */
		if (cpu_has(c, df->feature) &&
255 256 257
		    ((s32)df->level < 0 ?
		     (u32)df->level > (u32)c->extended_cpuid_level :
		     (s32)df->level > (s32)c->cpuid_level)) {
258 259 260 261 262 263 264 265 266
			clear_cpu_cap(c, df->feature);
			if (warn)
				printk(KERN_WARNING
				       "CPU: CPU feature %s disabled "
				       "due to lack of CPUID level 0x%x\n",
				       x86_cap_flags[df->feature],
				       df->level);
		}
	}
267
}
268

269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296
/*
 * Naming convention should be: <Name> [(<Codename>)]
 * This table only is used unless init_<vendor>() below doesn't set it;
 * in particular, if CPUID levels 0x80000002..4 are supported, this isn't used
 *
 */

/* Look up CPU names by table lookup. */
static char __cpuinit *table_lookup_model(struct cpuinfo_x86 *c)
{
	struct cpu_model_info *info;

	if (c->x86_model >= 16)
		return NULL;	/* Range check */

	if (!this_cpu)
		return NULL;

	info = this_cpu->c_models;

	while (info && info->family) {
		if (info->family == c->x86)
			return info->model_names[c->x86_model];
		info++;
	}
	return NULL;		/* Not found */
}

297 298
__u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;

299 300 301 302 303 304 305 306
void load_percpu_segment(int cpu)
{
#ifdef CONFIG_X86_32
	loadsegment(fs, __KERNEL_PERCPU);
#else
	loadsegment(gs, 0);
	wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
#endif
307
	load_stack_canary_segment();
308 309
}

310 311
/* Current gdt points %fs at the "master" per-cpu area: after this,
 * it's on the real one. */
312
void switch_to_new_gdt(int cpu)
313 314 315
{
	struct desc_ptr gdt_descr;

316
	gdt_descr.address = (long)get_cpu_gdt_table(cpu);
317 318
	gdt_descr.size = GDT_SIZE - 1;
	load_gdt(&gdt_descr);
319
	/* Reload the per-cpu base */
320 321

	load_percpu_segment(cpu);
322 323
}

Y
Yinghai Lu 已提交
324
static struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
L
Linus Torvalds 已提交
325

326
static void __cpuinit default_init(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
327
{
328 329 330
#ifdef CONFIG_X86_64
	display_cacheinfo(c);
#else
L
Linus Torvalds 已提交
331 332 333 334 335 336 337 338 339
	/* Not much we can do here... */
	/* Check if at least it has cpuid */
	if (c->cpuid_level == -1) {
		/* No cpuid. It must be an ancient CPU */
		if (c->x86 == 4)
			strcpy(c->x86_model_id, "486");
		else if (c->x86 == 3)
			strcpy(c->x86_model_id, "386");
	}
340
#endif
L
Linus Torvalds 已提交
341 342
}

343
static struct cpu_dev __cpuinitdata default_cpu = {
L
Linus Torvalds 已提交
344
	.c_init	= default_init,
345
	.c_vendor = "Unknown",
Y
Yinghai Lu 已提交
346
	.c_x86_vendor = X86_VENDOR_UNKNOWN,
L
Linus Torvalds 已提交
347 348
};

349
static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
350 351 352 353
{
	unsigned int *v;
	char *p, *q;

354
	if (c->extended_cpuid_level < 0x80000004)
355
		return;
L
Linus Torvalds 已提交
356 357 358 359 360 361 362 363 364 365

	v = (unsigned int *) c->x86_model_id;
	cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
	cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
	cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
	c->x86_model_id[48] = 0;

	/* Intel chips right-justify this string for some dumb reason;
	   undo that brain damage */
	p = q = &c->x86_model_id[0];
366
	while (*p == ' ')
L
Linus Torvalds 已提交
367
	     p++;
368 369
	if (p != q) {
	     while (*p)
L
Linus Torvalds 已提交
370
		  *q++ = *p++;
371
	     while (q <= &c->x86_model_id[48])
L
Linus Torvalds 已提交
372 373 374 375
		  *q++ = '\0';	/* Zero-pad the rest */
	}
}

376
void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
377
{
378
	unsigned int n, dummy, ebx, ecx, edx, l2size;
L
Linus Torvalds 已提交
379

380
	n = c->extended_cpuid_level;
L
Linus Torvalds 已提交
381 382

	if (n >= 0x80000005) {
383
		cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
L
Linus Torvalds 已提交
384
		printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
385 386
				edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
		c->x86_cache_size = (ecx>>24) + (edx>>24);
387 388 389 390
#ifdef CONFIG_X86_64
		/* On K8 L1 TLB is inclusive, so don't count it */
		c->x86_tlbsize = 0;
#endif
L
Linus Torvalds 已提交
391 392 393 394 395
	}

	if (n < 0x80000006)	/* Some chips just has a large L1. */
		return;

396
	cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
L
Linus Torvalds 已提交
397
	l2size = ecx >> 16;
398

399 400 401
#ifdef CONFIG_X86_64
	c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
#else
L
Linus Torvalds 已提交
402 403
	/* do processor-specific cache resizing */
	if (this_cpu->c_size_cache)
404
		l2size = this_cpu->c_size_cache(c, l2size);
L
Linus Torvalds 已提交
405 406 407 408 409

	/* Allow user to override all this if necessary. */
	if (cachesize_override != -1)
		l2size = cachesize_override;

410
	if (l2size == 0)
L
Linus Torvalds 已提交
411
		return;		/* Again, no L2 cache is possible */
412
#endif
L
Linus Torvalds 已提交
413 414 415 416

	c->x86_cache_size = l2size;

	printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
417
			l2size, ecx & 0xFF);
L
Linus Torvalds 已提交
418 419
}

420
void __cpuinit detect_ht(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
421
{
422
#ifdef CONFIG_X86_HT
423 424
	u32 eax, ebx, ecx, edx;
	int index_msb, core_bits;
L
Linus Torvalds 已提交
425

426
	if (!cpu_has(c, X86_FEATURE_HT))
427
		return;
L
Linus Torvalds 已提交
428

429 430
	if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
		goto out;
L
Linus Torvalds 已提交
431

432 433
	if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
		return;
L
Linus Torvalds 已提交
434

435
	cpuid(1, &eax, &ebx, &ecx, &edx);
L
Linus Torvalds 已提交
436

437 438 439 440 441 442
	smp_num_siblings = (ebx & 0xff0000) >> 16;

	if (smp_num_siblings == 1) {
		printk(KERN_INFO  "CPU: Hyper-Threading is disabled\n");
	} else if (smp_num_siblings > 1) {

443
		if (smp_num_siblings > nr_cpu_ids) {
444 445 446 447 448 449 450
			printk(KERN_WARNING "CPU: Unsupported number of siblings %d",
					smp_num_siblings);
			smp_num_siblings = 1;
			return;
		}

		index_msb = get_count_order(smp_num_siblings);
451
		c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
452 453 454 455 456 457 458

		smp_num_siblings = smp_num_siblings / c->x86_max_cores;

		index_msb = get_count_order(smp_num_siblings);

		core_bits = get_count_order(c->x86_max_cores);

459
		c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
460
					       ((1 << core_bits) - 1);
L
Linus Torvalds 已提交
461 462
	}

463 464 465 466 467 468
out:
	if ((c->x86_max_cores * smp_num_siblings) > 1) {
		printk(KERN_INFO  "CPU: Physical Processor ID: %d\n",
		       c->phys_proc_id);
		printk(KERN_INFO  "CPU: Processor Core ID: %d\n",
		       c->cpu_core_id);
469 470
	}
#endif
471
}
L
Linus Torvalds 已提交
472

473
static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
474 475 476
{
	char *v = c->x86_vendor_id;
	int i;
477
	static int printed;
L
Linus Torvalds 已提交
478 479

	for (i = 0; i < X86_VENDOR_NUM; i++) {
Y
Yinghai Lu 已提交
480 481 482 483 484 485 486 487 488
		if (!cpu_devs[i])
			break;

		if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
		    (cpu_devs[i]->c_ident[1] &&
		     !strcmp(v, cpu_devs[i]->c_ident[1]))) {
			this_cpu = cpu_devs[i];
			c->x86_vendor = this_cpu->c_x86_vendor;
			return;
L
Linus Torvalds 已提交
489 490
		}
	}
Y
Yinghai Lu 已提交
491

492 493
	if (!printed) {
		printed++;
494
		printk(KERN_ERR "CPU: vendor_id '%s' unknown, using generic init.\n", v);
495 496
		printk(KERN_ERR "CPU: Your system may be unstable.\n");
	}
Y
Yinghai Lu 已提交
497

498 499
	c->x86_vendor = X86_VENDOR_UNKNOWN;
	this_cpu = &default_cpu;
L
Linus Torvalds 已提交
500 501
}

502
void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
503 504
{
	/* Get vendor name */
505 506 507 508
	cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
	      (unsigned int *)&c->x86_vendor_id[0],
	      (unsigned int *)&c->x86_vendor_id[8],
	      (unsigned int *)&c->x86_vendor_id[4]);
L
Linus Torvalds 已提交
509 510

	c->x86 = 4;
511
	/* Intel-defined flags: level 0x00000001 */
L
Linus Torvalds 已提交
512 513 514
	if (c->cpuid_level >= 0x00000001) {
		u32 junk, tfms, cap0, misc;
		cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
515 516 517
		c->x86 = (tfms >> 8) & 0xf;
		c->x86_model = (tfms >> 4) & 0xf;
		c->x86_mask = tfms & 0xf;
518
		if (c->x86 == 0xf)
L
Linus Torvalds 已提交
519
			c->x86 += (tfms >> 20) & 0xff;
520
		if (c->x86 >= 0x6)
521
			c->x86_model += ((tfms >> 16) & 0xf) << 4;
H
Huang, Ying 已提交
522 523
		if (cap0 & (1<<19)) {
			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
524
			c->x86_cache_alignment = c->x86_clflush_size;
H
Huang, Ying 已提交
525
		}
L
Linus Torvalds 已提交
526 527
	}
}
528 529

static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
530 531
{
	u32 tfms, xlvl;
532
	u32 ebx;
533

534 535 536 537 538 539 540
	/* Intel-defined flags: level 0x00000001 */
	if (c->cpuid_level >= 0x00000001) {
		u32 capability, excap;
		cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
		c->x86_capability[0] = capability;
		c->x86_capability[4] = excap;
	}
541

542 543 544 545 546 547 548
	/* AMD-defined flags: level 0x80000001 */
	xlvl = cpuid_eax(0x80000000);
	c->extended_cpuid_level = xlvl;
	if ((xlvl & 0xffff0000) == 0x80000000) {
		if (xlvl >= 0x80000001) {
			c->x86_capability[1] = cpuid_edx(0x80000001);
			c->x86_capability[6] = cpuid_ecx(0x80000001);
549 550 551
		}
	}

552 553 554 555 556 557
#ifdef CONFIG_X86_64
	if (c->extended_cpuid_level >= 0x80000008) {
		u32 eax = cpuid_eax(0x80000008);

		c->x86_virt_bits = (eax >> 8) & 0xff;
		c->x86_phys_bits = eax & 0xff;
558
	}
559
#endif
560 561 562

	if (c->extended_cpuid_level >= 0x80000007)
		c->x86_power = cpuid_edx(0x80000007);
563 564

}
L
Linus Torvalds 已提交
565

Y
Yinghai Lu 已提交
566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591
static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
{
#ifdef CONFIG_X86_32
	int i;

	/*
	 * First of all, decide if this is a 486 or higher
	 * It's a 486 if we can modify the AC flag
	 */
	if (flag_is_changeable_p(X86_EFLAGS_AC))
		c->x86 = 4;
	else
		c->x86 = 3;

	for (i = 0; i < X86_VENDOR_NUM; i++)
		if (cpu_devs[i] && cpu_devs[i]->c_identify) {
			c->x86_vendor_id[0] = 0;
			cpu_devs[i]->c_identify(c);
			if (c->x86_vendor_id[0]) {
				get_cpu_vendor(c);
				break;
			}
		}
#endif
}

592 593 594 595 596 597 598 599 600
/*
 * Do minimum CPU detection early.
 * Fields really needed: vendor, cpuid_level, family, model, mask,
 * cache alignment.
 * The others are not touched to avoid unwanted side effects.
 *
 * WARNING: this function is only called on the BP.  Don't add code here
 * that is supposed to run on all CPUs.
 */
601
static void __init early_identify_cpu(struct cpuinfo_x86 *c)
602
{
603 604 605
#ifdef CONFIG_X86_64
	c->x86_clflush_size = 64;
#else
H
Huang, Ying 已提交
606
	c->x86_clflush_size = 32;
607
#endif
608
	c->x86_cache_alignment = c->x86_clflush_size;
609

610
	memset(&c->x86_capability, 0, sizeof c->x86_capability);
611
	c->extended_cpuid_level = 0;
612

Y
Yinghai Lu 已提交
613 614 615 616
	if (!have_cpuid_p())
		identify_cpu_without_cpuid(c);

	/* cyrix could have cpuid enabled via c_identify()*/
617 618 619 620 621
	if (!have_cpuid_p())
		return;

	cpu_detect(c);

622
	get_cpu_vendor(c);
623

624
	get_cpu_cap(c);
625

Y
Yinghai Lu 已提交
626 627
	if (this_cpu->c_early_init)
		this_cpu->c_early_init(c);
628

I
Ingo Molnar 已提交
629
#ifdef CONFIG_SMP
630
	c->cpu_index = boot_cpu_id;
I
Ingo Molnar 已提交
631
#endif
632
	filter_cpuid_features(c, false);
633 634
}

635 636
void __init early_cpu_init(void)
{
Y
Yinghai Lu 已提交
637 638 639 640 641 642 643
	struct cpu_dev **cdev;
	int count = 0;

	printk("KERNEL supported cpus:\n");
	for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
		struct cpu_dev *cpudev = *cdev;
		unsigned int j;
644

Y
Yinghai Lu 已提交
645 646 647 648 649 650 651 652 653 654 655 656
		if (count >= X86_VENDOR_NUM)
			break;
		cpu_devs[count] = cpudev;
		count++;

		for (j = 0; j < 2; j++) {
			if (!cpudev->c_ident[j])
				continue;
			printk("  %s %s\n", cpudev->c_vendor,
				cpudev->c_ident[j]);
		}
	}
657 658

	early_identify_cpu(&boot_cpu_data);
659
}
660

661 662
/*
 * The NOPL instruction is supposed to exist on all CPUs with
663
 * family >= 6; unfortunately, that's not true in practice because
664
 * of early VIA chips and (more importantly) broken virtualizers that
665 666 667
 * are not easy to detect.  In the latter case it doesn't even *fail*
 * reliably, so probing for it doesn't even work.  Disable it completely
 * unless we can find a reliable way to detect all the broken cases.
668 669 670 671
 */
static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
{
	clear_cpu_cap(c, X86_FEATURE_NOPL);
672 673
}

674
static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
675
{
Y
Yinghai Lu 已提交
676
	c->extended_cpuid_level = 0;
L
Linus Torvalds 已提交
677

678
	if (!have_cpuid_p())
Y
Yinghai Lu 已提交
679
		identify_cpu_without_cpuid(c);
680

Y
Yinghai Lu 已提交
681
	/* cyrix could have cpuid enabled via c_identify()*/
I
Ingo Molnar 已提交
682
	if (!have_cpuid_p())
Y
Yinghai Lu 已提交
683
		return;
L
Linus Torvalds 已提交
684

685
	cpu_detect(c);
L
Linus Torvalds 已提交
686

687
	get_cpu_vendor(c);
L
Linus Torvalds 已提交
688

689
	get_cpu_cap(c);
L
Linus Torvalds 已提交
690

691 692
	if (c->cpuid_level >= 0x00000001) {
		c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
693 694
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_HT
695
		c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
696
# else
697
		c->apicid = c->initial_apicid;
698 699
# endif
#endif
L
Linus Torvalds 已提交
700

701 702
#ifdef CONFIG_X86_HT
		c->phys_proc_id = c->initial_apicid;
703
#endif
704
	}
L
Linus Torvalds 已提交
705

706
	get_model_name(c); /* Default name */
L
Linus Torvalds 已提交
707

708 709
	init_scattered_cpuid_features(c);
	detect_nopl(c);
L
Linus Torvalds 已提交
710 711 712 713 714
}

/*
 * This does the hard work of actually picking apart the CPU stuff...
 */
Y
Yinghai Lu 已提交
715
static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
716 717 718 719 720 721 722 723 724
{
	int i;

	c->loops_per_jiffy = loops_per_jiffy;
	c->x86_cache_size = -1;
	c->x86_vendor = X86_VENDOR_UNKNOWN;
	c->x86_model = c->x86_mask = 0;	/* So far unknown... */
	c->x86_vendor_id[0] = '\0'; /* Unset */
	c->x86_model_id[0] = '\0';  /* Unset */
725
	c->x86_max_cores = 1;
726
	c->x86_coreid_bits = 0;
727
#ifdef CONFIG_X86_64
728 729 730
	c->x86_clflush_size = 64;
#else
	c->cpuid_level = -1;	/* CPUID not detected */
731
	c->x86_clflush_size = 32;
732 733
#endif
	c->x86_cache_alignment = c->x86_clflush_size;
L
Linus Torvalds 已提交
734 735 736 737
	memset(&c->x86_capability, 0, sizeof c->x86_capability);

	generic_identify(c);

738
	if (this_cpu->c_identify)
L
Linus Torvalds 已提交
739 740
		this_cpu->c_identify(c);

741
#ifdef CONFIG_X86_64
742
	c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
743 744
#endif

L
Linus Torvalds 已提交
745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765
	/*
	 * Vendor-specific initialization.  In this section we
	 * canonicalize the feature flags, meaning if there are
	 * features a certain CPU supports which CPUID doesn't
	 * tell us, CPUID claiming incorrect flags, or other bugs,
	 * we handle them here.
	 *
	 * At the end of this section, c->x86_capability better
	 * indicate the features this CPU genuinely supports!
	 */
	if (this_cpu->c_init)
		this_cpu->c_init(c);

	/* Disable the PN if appropriate */
	squash_the_stupid_serial_number(c);

	/*
	 * The vendor-specific functions might have changed features.  Now
	 * we do "generic changes."
	 */

766 767 768
	/* Filter out anything that depends on CPUID levels we don't have */
	filter_cpuid_features(c, true);

L
Linus Torvalds 已提交
769
	/* If the model name is still unset, do table lookup. */
770
	if (!c->x86_model_id[0]) {
L
Linus Torvalds 已提交
771 772
		char *p;
		p = table_lookup_model(c);
773
		if (p)
L
Linus Torvalds 已提交
774 775 776 777
			strcpy(c->x86_model_id, p);
		else
			/* Last resort... */
			sprintf(c->x86_model_id, "%02x/%02x",
778
				c->x86, c->x86_model);
L
Linus Torvalds 已提交
779 780
	}

781 782 783 784
#ifdef CONFIG_X86_64
	detect_ht(c);
#endif

785
	init_hypervisor(c);
L
Linus Torvalds 已提交
786 787 788 789 790 791
	/*
	 * On SMP, boot_cpu_data holds the common feature set between
	 * all CPUs; so make sure that we indicate which features are
	 * common between the CPUs.  The first time this routine gets
	 * executed, c == &boot_cpu_data.
	 */
792
	if (c != &boot_cpu_data) {
L
Linus Torvalds 已提交
793
		/* AND the already accumulated flags with these */
794
		for (i = 0; i < NCAPINTS; i++)
L
Linus Torvalds 已提交
795 796 797
			boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
	}

798 799
	/* Clear all flags overriden by options */
	for (i = 0; i < NCAPINTS; i++)
800
		c->x86_capability[i] &= ~cleared_cpu_caps[i];
801

802
#ifdef CONFIG_X86_MCE
L
Linus Torvalds 已提交
803 804
	/* Init Machine Check Exception if available. */
	mcheck_init(c);
805
#endif
806 807

	select_idle_routine(c);
808 809 810 811

#if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
	numa_add_cpu(smp_processor_id());
#endif
812
}
S
Shaohua Li 已提交
813

814 815 816 817 818 819 820 821 822 823
#ifdef CONFIG_X86_64
static void vgetcpu_set_mode(void)
{
	if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
		vgetcpu_mode = VGETCPU_RDTSCP;
	else
		vgetcpu_mode = VGETCPU_LSL;
}
#endif

824 825 826
void __init identify_boot_cpu(void)
{
	identify_cpu(&boot_cpu_data);
827
#ifdef CONFIG_X86_32
828
	sysenter_setup();
L
Li Shaohua 已提交
829
	enable_sep_cpu();
830 831
#else
	vgetcpu_set_mode();
832
#endif
833
}
S
Shaohua Li 已提交
834

835 836 837 838
void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
{
	BUG_ON(c == &boot_cpu_data);
	identify_cpu(c);
839
#ifdef CONFIG_X86_32
840
	enable_sep_cpu();
841
#endif
842
	mtrr_ap_init();
L
Linus Torvalds 已提交
843 844
}

845 846 847 848
struct msr_range {
	unsigned min;
	unsigned max;
};
L
Linus Torvalds 已提交
849

850 851 852 853 854 855
static struct msr_range msr_range_array[] __cpuinitdata = {
	{ 0x00000000, 0x00000418},
	{ 0xc0000000, 0xc000040b},
	{ 0xc0010000, 0xc0010142},
	{ 0xc0011000, 0xc001103b},
};
L
Linus Torvalds 已提交
856

857 858 859 860 861 862 863 864 865 866 867 868 869 870
static void __cpuinit print_cpu_msr(void)
{
	unsigned index;
	u64 val;
	int i;
	unsigned index_min, index_max;

	for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
		index_min = msr_range_array[i].min;
		index_max = msr_range_array[i].max;
		for (index = index_min; index < index_max; index++) {
			if (rdmsrl_amd_safe(index, &val))
				continue;
			printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
L
Linus Torvalds 已提交
871
		}
872 873
	}
}
874

875 876 877 878
static int show_msr __cpuinitdata;
static __init int setup_show_msr(char *arg)
{
	int num;
879

880
	get_option(&arg, &num);
881

882 883 884
	if (num > 0)
		show_msr = num;
	return 1;
L
Linus Torvalds 已提交
885
}
886
__setup("show_msr=", setup_show_msr);
L
Linus Torvalds 已提交
887

A
Andi Kleen 已提交
888 889 890 891 892 893 894
static __init int setup_noclflush(char *arg)
{
	setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
	return 1;
}
__setup("noclflush", setup_noclflush);

895
void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
L
Linus Torvalds 已提交
896 897 898 899 900 901 902 903
{
	char *vendor = NULL;

	if (c->x86_vendor < X86_VENDOR_NUM)
		vendor = this_cpu->c_vendor;
	else if (c->cpuid_level >= 0)
		vendor = c->x86_vendor_id;

904
	if (vendor && !strstr(c->x86_model_id, vendor))
905
		printk(KERN_CONT "%s ", vendor);
L
Linus Torvalds 已提交
906

907 908
	if (c->x86_model_id[0])
		printk(KERN_CONT "%s", c->x86_model_id);
L
Linus Torvalds 已提交
909
	else
910
		printk(KERN_CONT "%d86", c->x86);
L
Linus Torvalds 已提交
911

912
	if (c->x86_mask || c->cpuid_level >= 0)
913
		printk(KERN_CONT " stepping %02x\n", c->x86_mask);
L
Linus Torvalds 已提交
914
	else
915
		printk(KERN_CONT "\n");
916 917 918 919 920 921 922 923

#ifdef CONFIG_SMP
	if (c->cpu_index < show_msr)
		print_cpu_msr();
#else
	if (show_msr)
		print_cpu_msr();
#endif
L
Linus Torvalds 已提交
924 925
}

926 927 928 929 930 931 932 933 934 935 936
static __init int setup_disablecpuid(char *arg)
{
	int bit;
	if (get_option(&arg, &bit) && bit < NCAPINTS*32)
		setup_clear_cpu_cap(bit);
	else
		return 0;
	return 1;
}
__setup("clearcpuid=", setup_disablecpuid);

937 938 939
#ifdef CONFIG_X86_64
struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };

940 941
DEFINE_PER_CPU_FIRST(union irq_stack_union,
		     irq_stack_union) __aligned(PAGE_SIZE);
942
DEFINE_PER_CPU(char *, irq_stack_ptr) =
943
	init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
944

945 946 947
DEFINE_PER_CPU(unsigned long, kernel_stack) =
	(unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
EXPORT_PER_CPU_SYMBOL(kernel_stack);
948

949
DEFINE_PER_CPU(unsigned int, irq_count) = -1;
950

951 952 953
static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
	[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ])
	__aligned(PAGE_SIZE);
954 955 956 957 958

extern asmlinkage void ignore_sysret(void);

/* May not be marked __init: used by software suspend */
void syscall_init(void)
L
Linus Torvalds 已提交
959
{
960 961 962 963 964 965 966 967
	/*
	 * LSTAR and STAR live in a bit strange symbiosis.
	 * They both write to the same internal register. STAR allows to
	 * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
	 */
	wrmsrl(MSR_STAR,  ((u64)__USER32_CS)<<48  | ((u64)__KERNEL_CS)<<32);
	wrmsrl(MSR_LSTAR, system_call);
	wrmsrl(MSR_CSTAR, ignore_sysret);
968

969 970 971
#ifdef CONFIG_IA32_EMULATION
	syscall32_cpu_init();
#endif
972

973 974 975
	/* Flags to clear on syscall */
	wrmsrl(MSR_SYSCALL_MASK,
	       X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
L
Linus Torvalds 已提交
976
}
977

978 979 980 981 982 983 984 985
unsigned long kernel_eflags;

/*
 * Copies of the original ist values from the tss are only accessed during
 * debugging, no special alignment required.
 */
DEFINE_PER_CPU(struct orig_ist, orig_ist);

986
#else	/* x86_64 */
987

988 989 990
#ifdef CONFIG_CC_STACKPROTECTOR
DEFINE_PER_CPU(unsigned long, stack_canary);
#endif
991

992
/* Make sure %fs and %gs are initialized properly in idle threads */
A
Adrian Bunk 已提交
993
struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
994 995
{
	memset(regs, 0, sizeof(struct pt_regs));
996
	regs->fs = __KERNEL_PERCPU;
997
	regs->gs = __KERNEL_STACK_CANARY;
998 999
	return regs;
}
1000
#endif	/* x86_64 */
1001

1002 1003 1004 1005 1006
/*
 * cpu_init() initializes state that is per-CPU. Some data is already
 * initialized (naturally) in the bootstrap process, such as the GDT
 * and IDT. We reload them nevertheless, this function acts as a
 * 'CPU state barrier', nothing should get across.
1007
 * A lot of state is already set up in PDA init for 64 bit
1008
 */
1009 1010 1011 1012 1013 1014 1015 1016 1017 1018
#ifdef CONFIG_X86_64
void __cpuinit cpu_init(void)
{
	int cpu = stack_smp_processor_id();
	struct tss_struct *t = &per_cpu(init_tss, cpu);
	struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
	unsigned long v;
	struct task_struct *me;
	int i;

1019 1020 1021 1022 1023
#ifdef CONFIG_NUMA
	if (cpu != 0 && percpu_read(node_number) == 0 &&
	    cpu_to_node(cpu) != NUMA_NO_NODE)
		percpu_write(node_number, cpu_to_node(cpu));
#endif
1024 1025 1026

	me = current;

1027
	if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038
		panic("CPU#%d already initialized!\n", cpu);

	printk(KERN_INFO "Initializing CPU#%d\n", cpu);

	clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);

	/*
	 * Initialize the per-CPU GDT with the boot GDT,
	 * and set up the GDT descriptor:
	 */

1039
	switch_to_new_gdt(cpu);
1040 1041
	loadsegment(fs, 0);

1042 1043 1044 1045 1046 1047 1048 1049 1050 1051
	load_idt((const struct desc_ptr *)&idt_descr);

	memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
	syscall_init();

	wrmsrl(MSR_FS_BASE, 0);
	wrmsrl(MSR_KERNEL_GS_BASE, 0);
	barrier();

	check_efer();
Y
Yinghai Lu 已提交
1052
	if (cpu != 0)
1053 1054 1055 1056 1057 1058
		enable_x2apic();

	/*
	 * set up and load the per-CPU TSS
	 */
	if (!orig_ist->ist[0]) {
1059 1060 1061
		static const unsigned int sizes[N_EXCEPTION_STACKS] = {
		  [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
		  [DEBUG_STACK - 1] = DEBUG_STKSZ
1062
		};
1063
		char *estacks = per_cpu(exception_stacks, cpu);
1064
		for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1065
			estacks += sizes[v];
1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
			orig_ist->ist[v] = t->x86_tss.ist[v] =
					(unsigned long)estacks;
		}
	}

	t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
	/*
	 * <= is required because the CPU will access up to
	 * 8 bits beyond the end of the IO permission bitmap.
	 */
	for (i = 0; i <= IO_BITMAP_LONGS; i++)
		t->io_bitmap[i] = ~0UL;

	atomic_inc(&init_mm.mm_count);
	me->active_mm = &init_mm;
S
Stoyan Gaydarov 已提交
1081
	BUG_ON(me->mm);
1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
	enter_lazy_tlb(&init_mm, me);

	load_sp0(t, &current->thread);
	set_tss_desc(cpu, t);
	load_TR_desc();
	load_LDT(&init_mm.context);

#ifdef CONFIG_KGDB
	/*
	 * If the kgdb is connected no debug regs should be altered.  This
	 * is only applicable when KGDB and a KGDB I/O module are built
	 * into the kernel and you are using early debugging with
	 * kgdbwait. KGDB will control the kernel HW breakpoint registers.
	 */
	if (kgdb_connected && arch_kgdb_ops.correct_hw_break)
		arch_kgdb_ops.correct_hw_break();
1098
	else
1099
#endif
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109
	{
		/*
		 * Clear all 6 debug registers:
		 */
		set_debugreg(0UL, 0);
		set_debugreg(0UL, 1);
		set_debugreg(0UL, 2);
		set_debugreg(0UL, 3);
		set_debugreg(0UL, 6);
		set_debugreg(0UL, 7);
1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121
	}

	fpu_init();

	raw_local_save_flags(kernel_eflags);

	if (is_uv_system())
		uv_cpu_init();
}

#else

1122
void __cpuinit cpu_init(void)
1123
{
1124 1125
	int cpu = smp_processor_id();
	struct task_struct *curr = current;
1126
	struct tss_struct *t = &per_cpu(init_tss, cpu);
1127
	struct thread_struct *thread = &curr->thread;
1128

1129
	if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
1130 1131 1132 1133 1134 1135 1136 1137 1138
		printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
		for (;;) local_irq_enable();
	}

	printk(KERN_INFO "Initializing CPU#%d\n", cpu);

	if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
		clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);

1139
	load_idt(&idt_descr);
1140
	switch_to_new_gdt(cpu);
L
Linus Torvalds 已提交
1141 1142 1143 1144 1145

	/*
	 * Set up and load the per-CPU TSS and LDT
	 */
	atomic_inc(&init_mm.mm_count);
1146
	curr->active_mm = &init_mm;
S
Stoyan Gaydarov 已提交
1147
	BUG_ON(curr->mm);
1148
	enter_lazy_tlb(&init_mm, curr);
L
Linus Torvalds 已提交
1149

1150
	load_sp0(t, thread);
1151
	set_tss_desc(cpu, t);
L
Linus Torvalds 已提交
1152 1153 1154
	load_TR_desc();
	load_LDT(&init_mm.context);

1155
#ifdef CONFIG_DOUBLEFAULT
L
Linus Torvalds 已提交
1156 1157
	/* Set up doublefault TSS pointer in the GDT */
	__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1158
#endif
L
Linus Torvalds 已提交
1159 1160

	/* Clear all 6 debug registers: */
1161 1162 1163 1164 1165 1166
	set_debugreg(0, 0);
	set_debugreg(0, 1);
	set_debugreg(0, 2);
	set_debugreg(0, 3);
	set_debugreg(0, 6);
	set_debugreg(0, 7);
L
Linus Torvalds 已提交
1167 1168 1169 1170

	/*
	 * Force FPU initialization:
	 */
1171 1172 1173 1174
	if (cpu_has_xsave)
		current_thread_info()->status = TS_XSAVE;
	else
		current_thread_info()->status = 0;
L
Linus Torvalds 已提交
1175 1176
	clear_used_math();
	mxcsr_feature_mask_init();
1177 1178 1179 1180

	/*
	 * Boot processor to setup the FP and extended state context info.
	 */
1181
	if (smp_processor_id() == boot_cpu_id)
1182 1183 1184
		init_thread_xstate();

	xsave_init();
L
Linus Torvalds 已提交
1185
}
1186

1187 1188

#endif