common.c 16 KB

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  1. #include <linux/init.h>
  2. #include <linux/string.h>
  3. #include <linux/delay.h>
  4. #include <linux/smp.h>
  5. #include <linux/module.h>
  6. #include <linux/percpu.h>
  7. #include <asm/semaphore.h>
  8. #include <asm/processor.h>
  9. #include <asm/i387.h>
  10. #include <asm/msr.h>
  11. #include <asm/io.h>
  12. #include <asm/mmu_context.h>
  13. #ifdef CONFIG_X86_LOCAL_APIC
  14. #include <asm/mpspec.h>
  15. #include <asm/apic.h>
  16. #include <mach_apic.h>
  17. #endif
  18. #include "cpu.h"
  19. DEFINE_PER_CPU(struct desc_struct, cpu_gdt_table[GDT_ENTRIES]);
  20. EXPORT_PER_CPU_SYMBOL(cpu_gdt_table);
  21. DEFINE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
  22. EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
  23. static int cachesize_override __initdata = -1;
  24. static int disable_x86_fxsr __initdata = 0;
  25. static int disable_x86_serial_nr __initdata = 1;
  26. struct cpu_dev * cpu_devs[X86_VENDOR_NUM] = {};
  27. extern void mcheck_init(struct cpuinfo_x86 *c);
  28. extern int disable_pse;
  29. static void default_init(struct cpuinfo_x86 * c)
  30. {
  31. /* Not much we can do here... */
  32. /* Check if at least it has cpuid */
  33. if (c->cpuid_level == -1) {
  34. /* No cpuid. It must be an ancient CPU */
  35. if (c->x86 == 4)
  36. strcpy(c->x86_model_id, "486");
  37. else if (c->x86 == 3)
  38. strcpy(c->x86_model_id, "386");
  39. }
  40. }
  41. static struct cpu_dev default_cpu = {
  42. .c_init = default_init,
  43. };
  44. static struct cpu_dev * this_cpu = &default_cpu;
  45. static int __init cachesize_setup(char *str)
  46. {
  47. get_option (&str, &cachesize_override);
  48. return 1;
  49. }
  50. __setup("cachesize=", cachesize_setup);
  51. int __init get_model_name(struct cpuinfo_x86 *c)
  52. {
  53. unsigned int *v;
  54. char *p, *q;
  55. if (cpuid_eax(0x80000000) < 0x80000004)
  56. return 0;
  57. v = (unsigned int *) c->x86_model_id;
  58. cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
  59. cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
  60. cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
  61. c->x86_model_id[48] = 0;
  62. /* Intel chips right-justify this string for some dumb reason;
  63. undo that brain damage */
  64. p = q = &c->x86_model_id[0];
  65. while ( *p == ' ' )
  66. p++;
  67. if ( p != q ) {
  68. while ( *p )
  69. *q++ = *p++;
  70. while ( q <= &c->x86_model_id[48] )
  71. *q++ = '\0'; /* Zero-pad the rest */
  72. }
  73. return 1;
  74. }
  75. void __init display_cacheinfo(struct cpuinfo_x86 *c)
  76. {
  77. unsigned int n, dummy, ecx, edx, l2size;
  78. n = cpuid_eax(0x80000000);
  79. if (n >= 0x80000005) {
  80. cpuid(0x80000005, &dummy, &dummy, &ecx, &edx);
  81. printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
  82. edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
  83. c->x86_cache_size=(ecx>>24)+(edx>>24);
  84. }
  85. if (n < 0x80000006) /* Some chips just has a large L1. */
  86. return;
  87. ecx = cpuid_ecx(0x80000006);
  88. l2size = ecx >> 16;
  89. /* do processor-specific cache resizing */
  90. if (this_cpu->c_size_cache)
  91. l2size = this_cpu->c_size_cache(c,l2size);
  92. /* Allow user to override all this if necessary. */
  93. if (cachesize_override != -1)
  94. l2size = cachesize_override;
  95. if ( l2size == 0 )
  96. return; /* Again, no L2 cache is possible */
  97. c->x86_cache_size = l2size;
  98. printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
  99. l2size, ecx & 0xFF);
  100. }
  101. /* Naming convention should be: <Name> [(<Codename>)] */
  102. /* This table only is used unless init_<vendor>() below doesn't set it; */
  103. /* in particular, if CPUID levels 0x80000002..4 are supported, this isn't used */
  104. /* Look up CPU names by table lookup. */
  105. static char __init *table_lookup_model(struct cpuinfo_x86 *c)
  106. {
  107. struct cpu_model_info *info;
  108. if ( c->x86_model >= 16 )
  109. return NULL; /* Range check */
  110. if (!this_cpu)
  111. return NULL;
  112. info = this_cpu->c_models;
  113. while (info && info->family) {
  114. if (info->family == c->x86)
  115. return info->model_names[c->x86_model];
  116. info++;
  117. }
  118. return NULL; /* Not found */
  119. }
  120. void __init get_cpu_vendor(struct cpuinfo_x86 *c, int early)
  121. {
  122. char *v = c->x86_vendor_id;
  123. int i;
  124. for (i = 0; i < X86_VENDOR_NUM; i++) {
  125. if (cpu_devs[i]) {
  126. if (!strcmp(v,cpu_devs[i]->c_ident[0]) ||
  127. (cpu_devs[i]->c_ident[1] &&
  128. !strcmp(v,cpu_devs[i]->c_ident[1]))) {
  129. c->x86_vendor = i;
  130. if (!early)
  131. this_cpu = cpu_devs[i];
  132. break;
  133. }
  134. }
  135. }
  136. }
  137. static int __init x86_fxsr_setup(char * s)
  138. {
  139. disable_x86_fxsr = 1;
  140. return 1;
  141. }
  142. __setup("nofxsr", x86_fxsr_setup);
  143. /* Standard macro to see if a specific flag is changeable */
  144. static inline int flag_is_changeable_p(u32 flag)
  145. {
  146. u32 f1, f2;
  147. asm("pushfl\n\t"
  148. "pushfl\n\t"
  149. "popl %0\n\t"
  150. "movl %0,%1\n\t"
  151. "xorl %2,%0\n\t"
  152. "pushl %0\n\t"
  153. "popfl\n\t"
  154. "pushfl\n\t"
  155. "popl %0\n\t"
  156. "popfl\n\t"
  157. : "=&r" (f1), "=&r" (f2)
  158. : "ir" (flag));
  159. return ((f1^f2) & flag) != 0;
  160. }
  161. /* Probe for the CPUID instruction */
  162. static int __init have_cpuid_p(void)
  163. {
  164. return flag_is_changeable_p(X86_EFLAGS_ID);
  165. }
  166. /* Do minimum CPU detection early.
  167. Fields really needed: vendor, cpuid_level, family, model, mask, cache alignment.
  168. The others are not touched to avoid unwanted side effects. */
  169. static void __init early_cpu_detect(void)
  170. {
  171. struct cpuinfo_x86 *c = &boot_cpu_data;
  172. c->x86_cache_alignment = 32;
  173. if (!have_cpuid_p())
  174. return;
  175. /* Get vendor name */
  176. cpuid(0x00000000, &c->cpuid_level,
  177. (int *)&c->x86_vendor_id[0],
  178. (int *)&c->x86_vendor_id[8],
  179. (int *)&c->x86_vendor_id[4]);
  180. get_cpu_vendor(c, 1);
  181. c->x86 = 4;
  182. if (c->cpuid_level >= 0x00000001) {
  183. u32 junk, tfms, cap0, misc;
  184. cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
  185. c->x86 = (tfms >> 8) & 15;
  186. c->x86_model = (tfms >> 4) & 15;
  187. if (c->x86 == 0xf) {
  188. c->x86 += (tfms >> 20) & 0xff;
  189. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  190. }
  191. c->x86_mask = tfms & 15;
  192. if (cap0 & (1<<19))
  193. c->x86_cache_alignment = ((misc >> 8) & 0xff) * 8;
  194. }
  195. early_intel_workaround(c);
  196. }
  197. void __init generic_identify(struct cpuinfo_x86 * c)
  198. {
  199. u32 tfms, xlvl;
  200. int junk;
  201. if (have_cpuid_p()) {
  202. /* Get vendor name */
  203. cpuid(0x00000000, &c->cpuid_level,
  204. (int *)&c->x86_vendor_id[0],
  205. (int *)&c->x86_vendor_id[8],
  206. (int *)&c->x86_vendor_id[4]);
  207. get_cpu_vendor(c, 0);
  208. /* Initialize the standard set of capabilities */
  209. /* Note that the vendor-specific code below might override */
  210. /* Intel-defined flags: level 0x00000001 */
  211. if ( c->cpuid_level >= 0x00000001 ) {
  212. u32 capability, excap;
  213. cpuid(0x00000001, &tfms, &junk, &excap, &capability);
  214. c->x86_capability[0] = capability;
  215. c->x86_capability[4] = excap;
  216. c->x86 = (tfms >> 8) & 15;
  217. c->x86_model = (tfms >> 4) & 15;
  218. if (c->x86 == 0xf) {
  219. c->x86 += (tfms >> 20) & 0xff;
  220. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  221. }
  222. c->x86_mask = tfms & 15;
  223. } else {
  224. /* Have CPUID level 0 only - unheard of */
  225. c->x86 = 4;
  226. }
  227. /* AMD-defined flags: level 0x80000001 */
  228. xlvl = cpuid_eax(0x80000000);
  229. if ( (xlvl & 0xffff0000) == 0x80000000 ) {
  230. if ( xlvl >= 0x80000001 ) {
  231. c->x86_capability[1] = cpuid_edx(0x80000001);
  232. c->x86_capability[6] = cpuid_ecx(0x80000001);
  233. }
  234. if ( xlvl >= 0x80000004 )
  235. get_model_name(c); /* Default name */
  236. }
  237. }
  238. }
  239. static void __init squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  240. {
  241. if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr ) {
  242. /* Disable processor serial number */
  243. unsigned long lo,hi;
  244. rdmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  245. lo |= 0x200000;
  246. wrmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  247. printk(KERN_NOTICE "CPU serial number disabled.\n");
  248. clear_bit(X86_FEATURE_PN, c->x86_capability);
  249. /* Disabling the serial number may affect the cpuid level */
  250. c->cpuid_level = cpuid_eax(0);
  251. }
  252. }
  253. static int __init x86_serial_nr_setup(char *s)
  254. {
  255. disable_x86_serial_nr = 0;
  256. return 1;
  257. }
  258. __setup("serialnumber", x86_serial_nr_setup);
  259. /*
  260. * This does the hard work of actually picking apart the CPU stuff...
  261. */
  262. void __init identify_cpu(struct cpuinfo_x86 *c)
  263. {
  264. int i;
  265. c->loops_per_jiffy = loops_per_jiffy;
  266. c->x86_cache_size = -1;
  267. c->x86_vendor = X86_VENDOR_UNKNOWN;
  268. c->cpuid_level = -1; /* CPUID not detected */
  269. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  270. c->x86_vendor_id[0] = '\0'; /* Unset */
  271. c->x86_model_id[0] = '\0'; /* Unset */
  272. c->x86_num_cores = 1;
  273. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  274. if (!have_cpuid_p()) {
  275. /* First of all, decide if this is a 486 or higher */
  276. /* It's a 486 if we can modify the AC flag */
  277. if ( flag_is_changeable_p(X86_EFLAGS_AC) )
  278. c->x86 = 4;
  279. else
  280. c->x86 = 3;
  281. }
  282. generic_identify(c);
  283. printk(KERN_DEBUG "CPU: After generic identify, caps:");
  284. for (i = 0; i < NCAPINTS; i++)
  285. printk(" %08lx", c->x86_capability[i]);
  286. printk("\n");
  287. if (this_cpu->c_identify) {
  288. this_cpu->c_identify(c);
  289. printk(KERN_DEBUG "CPU: After vendor identify, caps:");
  290. for (i = 0; i < NCAPINTS; i++)
  291. printk(" %08lx", c->x86_capability[i]);
  292. printk("\n");
  293. }
  294. /*
  295. * Vendor-specific initialization. In this section we
  296. * canonicalize the feature flags, meaning if there are
  297. * features a certain CPU supports which CPUID doesn't
  298. * tell us, CPUID claiming incorrect flags, or other bugs,
  299. * we handle them here.
  300. *
  301. * At the end of this section, c->x86_capability better
  302. * indicate the features this CPU genuinely supports!
  303. */
  304. if (this_cpu->c_init)
  305. this_cpu->c_init(c);
  306. /* Disable the PN if appropriate */
  307. squash_the_stupid_serial_number(c);
  308. /*
  309. * The vendor-specific functions might have changed features. Now
  310. * we do "generic changes."
  311. */
  312. /* TSC disabled? */
  313. if ( tsc_disable )
  314. clear_bit(X86_FEATURE_TSC, c->x86_capability);
  315. /* FXSR disabled? */
  316. if (disable_x86_fxsr) {
  317. clear_bit(X86_FEATURE_FXSR, c->x86_capability);
  318. clear_bit(X86_FEATURE_XMM, c->x86_capability);
  319. }
  320. if (disable_pse)
  321. clear_bit(X86_FEATURE_PSE, c->x86_capability);
  322. /* If the model name is still unset, do table lookup. */
  323. if ( !c->x86_model_id[0] ) {
  324. char *p;
  325. p = table_lookup_model(c);
  326. if ( p )
  327. strcpy(c->x86_model_id, p);
  328. else
  329. /* Last resort... */
  330. sprintf(c->x86_model_id, "%02x/%02x",
  331. c->x86_vendor, c->x86_model);
  332. }
  333. /* Now the feature flags better reflect actual CPU features! */
  334. printk(KERN_DEBUG "CPU: After all inits, caps:");
  335. for (i = 0; i < NCAPINTS; i++)
  336. printk(" %08lx", c->x86_capability[i]);
  337. printk("\n");
  338. /*
  339. * On SMP, boot_cpu_data holds the common feature set between
  340. * all CPUs; so make sure that we indicate which features are
  341. * common between the CPUs. The first time this routine gets
  342. * executed, c == &boot_cpu_data.
  343. */
  344. if ( c != &boot_cpu_data ) {
  345. /* AND the already accumulated flags with these */
  346. for ( i = 0 ; i < NCAPINTS ; i++ )
  347. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  348. }
  349. /* Init Machine Check Exception if available. */
  350. #ifdef CONFIG_X86_MCE
  351. mcheck_init(c);
  352. #endif
  353. }
  354. #ifdef CONFIG_X86_HT
  355. void __init detect_ht(struct cpuinfo_x86 *c)
  356. {
  357. u32 eax, ebx, ecx, edx;
  358. int index_msb, tmp;
  359. int cpu = smp_processor_id();
  360. if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
  361. return;
  362. cpuid(1, &eax, &ebx, &ecx, &edx);
  363. smp_num_siblings = (ebx & 0xff0000) >> 16;
  364. if (smp_num_siblings == 1) {
  365. printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
  366. } else if (smp_num_siblings > 1 ) {
  367. index_msb = 31;
  368. if (smp_num_siblings > NR_CPUS) {
  369. printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
  370. smp_num_siblings = 1;
  371. return;
  372. }
  373. tmp = smp_num_siblings;
  374. while ((tmp & 0x80000000 ) == 0) {
  375. tmp <<=1 ;
  376. index_msb--;
  377. }
  378. if (smp_num_siblings & (smp_num_siblings - 1))
  379. index_msb++;
  380. phys_proc_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
  381. printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
  382. phys_proc_id[cpu]);
  383. smp_num_siblings = smp_num_siblings / c->x86_num_cores;
  384. tmp = smp_num_siblings;
  385. index_msb = 31;
  386. while ((tmp & 0x80000000) == 0) {
  387. tmp <<=1 ;
  388. index_msb--;
  389. }
  390. if (smp_num_siblings & (smp_num_siblings - 1))
  391. index_msb++;
  392. cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
  393. if (c->x86_num_cores > 1)
  394. printk(KERN_INFO "CPU: Processor Core ID: %d\n",
  395. cpu_core_id[cpu]);
  396. }
  397. }
  398. #endif
  399. void __init print_cpu_info(struct cpuinfo_x86 *c)
  400. {
  401. char *vendor = NULL;
  402. if (c->x86_vendor < X86_VENDOR_NUM)
  403. vendor = this_cpu->c_vendor;
  404. else if (c->cpuid_level >= 0)
  405. vendor = c->x86_vendor_id;
  406. if (vendor && strncmp(c->x86_model_id, vendor, strlen(vendor)))
  407. printk("%s ", vendor);
  408. if (!c->x86_model_id[0])
  409. printk("%d86", c->x86);
  410. else
  411. printk("%s", c->x86_model_id);
  412. if (c->x86_mask || c->cpuid_level >= 0)
  413. printk(" stepping %02x\n", c->x86_mask);
  414. else
  415. printk("\n");
  416. }
  417. cpumask_t cpu_initialized __initdata = CPU_MASK_NONE;
  418. /* This is hacky. :)
  419. * We're emulating future behavior.
  420. * In the future, the cpu-specific init functions will be called implicitly
  421. * via the magic of initcalls.
  422. * They will insert themselves into the cpu_devs structure.
  423. * Then, when cpu_init() is called, we can just iterate over that array.
  424. */
  425. extern int intel_cpu_init(void);
  426. extern int cyrix_init_cpu(void);
  427. extern int nsc_init_cpu(void);
  428. extern int amd_init_cpu(void);
  429. extern int centaur_init_cpu(void);
  430. extern int transmeta_init_cpu(void);
  431. extern int rise_init_cpu(void);
  432. extern int nexgen_init_cpu(void);
  433. extern int umc_init_cpu(void);
  434. void __init early_cpu_init(void)
  435. {
  436. intel_cpu_init();
  437. cyrix_init_cpu();
  438. nsc_init_cpu();
  439. amd_init_cpu();
  440. centaur_init_cpu();
  441. transmeta_init_cpu();
  442. rise_init_cpu();
  443. nexgen_init_cpu();
  444. umc_init_cpu();
  445. early_cpu_detect();
  446. #ifdef CONFIG_DEBUG_PAGEALLOC
  447. /* pse is not compatible with on-the-fly unmapping,
  448. * disable it even if the cpus claim to support it.
  449. */
  450. clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability);
  451. disable_pse = 1;
  452. #endif
  453. }
  454. /*
  455. * cpu_init() initializes state that is per-CPU. Some data is already
  456. * initialized (naturally) in the bootstrap process, such as the GDT
  457. * and IDT. We reload them nevertheless, this function acts as a
  458. * 'CPU state barrier', nothing should get across.
  459. */
  460. void __init cpu_init (void)
  461. {
  462. int cpu = smp_processor_id();
  463. struct tss_struct * t = &per_cpu(init_tss, cpu);
  464. struct thread_struct *thread = &current->thread;
  465. __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
  466. if (cpu_test_and_set(cpu, cpu_initialized)) {
  467. printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
  468. for (;;) local_irq_enable();
  469. }
  470. printk(KERN_INFO "Initializing CPU#%d\n", cpu);
  471. if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
  472. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  473. if (tsc_disable && cpu_has_tsc) {
  474. printk(KERN_NOTICE "Disabling TSC...\n");
  475. /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
  476. clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
  477. set_in_cr4(X86_CR4_TSD);
  478. }
  479. /*
  480. * Initialize the per-CPU GDT with the boot GDT,
  481. * and set up the GDT descriptor:
  482. */
  483. memcpy(&per_cpu(cpu_gdt_table, cpu), cpu_gdt_table,
  484. GDT_SIZE);
  485. /* Set up GDT entry for 16bit stack */
  486. *(__u64 *)&(per_cpu(cpu_gdt_table, cpu)[GDT_ENTRY_ESPFIX_SS]) |=
  487. ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
  488. ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
  489. (CPU_16BIT_STACK_SIZE - 1);
  490. cpu_gdt_descr[cpu].size = GDT_SIZE - 1;
  491. cpu_gdt_descr[cpu].address =
  492. (unsigned long)&per_cpu(cpu_gdt_table, cpu);
  493. /*
  494. * Set up the per-thread TLS descriptor cache:
  495. */
  496. memcpy(thread->tls_array, &per_cpu(cpu_gdt_table, cpu),
  497. GDT_ENTRY_TLS_ENTRIES * 8);
  498. __asm__ __volatile__("lgdt %0" : : "m" (cpu_gdt_descr[cpu]));
  499. __asm__ __volatile__("lidt %0" : : "m" (idt_descr));
  500. /*
  501. * Delete NT
  502. */
  503. __asm__("pushfl ; andl $0xffffbfff,(%esp) ; popfl");
  504. /*
  505. * Set up and load the per-CPU TSS and LDT
  506. */
  507. atomic_inc(&init_mm.mm_count);
  508. current->active_mm = &init_mm;
  509. if (current->mm)
  510. BUG();
  511. enter_lazy_tlb(&init_mm, current);
  512. load_esp0(t, thread);
  513. set_tss_desc(cpu,t);
  514. load_TR_desc();
  515. load_LDT(&init_mm.context);
  516. /* Set up doublefault TSS pointer in the GDT */
  517. __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
  518. /* Clear %fs and %gs. */
  519. asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
  520. /* Clear all 6 debug registers: */
  521. #define CD(register) __asm__("movl %0,%%db" #register ::"r"(0) );
  522. CD(0); CD(1); CD(2); CD(3); /* no db4 and db5 */; CD(6); CD(7);
  523. #undef CD
  524. /*
  525. * Force FPU initialization:
  526. */
  527. current_thread_info()->status = 0;
  528. clear_used_math();
  529. mxcsr_feature_mask_init();
  530. }