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(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
  20. EXPORT_PER_CPU_SYMBOL(cpu_16bit_stack);
  21. static int cachesize_override __devinitdata = -1;
  22. static int disable_x86_fxsr __devinitdata = 0;
  23. static int disable_x86_serial_nr __devinitdata = 1;
  24. struct cpu_dev * cpu_devs[X86_VENDOR_NUM] = {};
  25. extern int disable_pse;
  26. static void default_init(struct cpuinfo_x86 * c)
  27. {
  28. /* Not much we can do here... */
  29. /* Check if at least it has cpuid */
  30. if (c->cpuid_level == -1) {
  31. /* No cpuid. It must be an ancient CPU */
  32. if (c->x86 == 4)
  33. strcpy(c->x86_model_id, "486");
  34. else if (c->x86 == 3)
  35. strcpy(c->x86_model_id, "386");
  36. }
  37. }
  38. static struct cpu_dev default_cpu = {
  39. .c_init = default_init,
  40. };
  41. static struct cpu_dev * this_cpu = &default_cpu;
  42. static int __init cachesize_setup(char *str)
  43. {
  44. get_option (&str, &cachesize_override);
  45. return 1;
  46. }
  47. __setup("cachesize=", cachesize_setup);
  48. int __devinit get_model_name(struct cpuinfo_x86 *c)
  49. {
  50. unsigned int *v;
  51. char *p, *q;
  52. if (cpuid_eax(0x80000000) < 0x80000004)
  53. return 0;
  54. v = (unsigned int *) c->x86_model_id;
  55. cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
  56. cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
  57. cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
  58. c->x86_model_id[48] = 0;
  59. /* Intel chips right-justify this string for some dumb reason;
  60. undo that brain damage */
  61. p = q = &c->x86_model_id[0];
  62. while ( *p == ' ' )
  63. p++;
  64. if ( p != q ) {
  65. while ( *p )
  66. *q++ = *p++;
  67. while ( q <= &c->x86_model_id[48] )
  68. *q++ = '\0'; /* Zero-pad the rest */
  69. }
  70. return 1;
  71. }
  72. void __devinit display_cacheinfo(struct cpuinfo_x86 *c)
  73. {
  74. unsigned int n, dummy, ecx, edx, l2size;
  75. n = cpuid_eax(0x80000000);
  76. if (n >= 0x80000005) {
  77. cpuid(0x80000005, &dummy, &dummy, &ecx, &edx);
  78. printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
  79. edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
  80. c->x86_cache_size=(ecx>>24)+(edx>>24);
  81. }
  82. if (n < 0x80000006) /* Some chips just has a large L1. */
  83. return;
  84. ecx = cpuid_ecx(0x80000006);
  85. l2size = ecx >> 16;
  86. /* do processor-specific cache resizing */
  87. if (this_cpu->c_size_cache)
  88. l2size = this_cpu->c_size_cache(c,l2size);
  89. /* Allow user to override all this if necessary. */
  90. if (cachesize_override != -1)
  91. l2size = cachesize_override;
  92. if ( l2size == 0 )
  93. return; /* Again, no L2 cache is possible */
  94. c->x86_cache_size = l2size;
  95. printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
  96. l2size, ecx & 0xFF);
  97. }
  98. /* Naming convention should be: <Name> [(<Codename>)] */
  99. /* This table only is used unless init_<vendor>() below doesn't set it; */
  100. /* in particular, if CPUID levels 0x80000002..4 are supported, this isn't used */
  101. /* Look up CPU names by table lookup. */
  102. static char __devinit *table_lookup_model(struct cpuinfo_x86 *c)
  103. {
  104. struct cpu_model_info *info;
  105. if ( c->x86_model >= 16 )
  106. return NULL; /* Range check */
  107. if (!this_cpu)
  108. return NULL;
  109. info = this_cpu->c_models;
  110. while (info && info->family) {
  111. if (info->family == c->x86)
  112. return info->model_names[c->x86_model];
  113. info++;
  114. }
  115. return NULL; /* Not found */
  116. }
  117. static void __devinit get_cpu_vendor(struct cpuinfo_x86 *c, int early)
  118. {
  119. char *v = c->x86_vendor_id;
  120. int i;
  121. for (i = 0; i < X86_VENDOR_NUM; i++) {
  122. if (cpu_devs[i]) {
  123. if (!strcmp(v,cpu_devs[i]->c_ident[0]) ||
  124. (cpu_devs[i]->c_ident[1] &&
  125. !strcmp(v,cpu_devs[i]->c_ident[1]))) {
  126. c->x86_vendor = i;
  127. if (!early)
  128. this_cpu = cpu_devs[i];
  129. break;
  130. }
  131. }
  132. }
  133. }
  134. static int __init x86_fxsr_setup(char * s)
  135. {
  136. disable_x86_fxsr = 1;
  137. return 1;
  138. }
  139. __setup("nofxsr", x86_fxsr_setup);
  140. /* Standard macro to see if a specific flag is changeable */
  141. static inline int flag_is_changeable_p(u32 flag)
  142. {
  143. u32 f1, f2;
  144. asm("pushfl\n\t"
  145. "pushfl\n\t"
  146. "popl %0\n\t"
  147. "movl %0,%1\n\t"
  148. "xorl %2,%0\n\t"
  149. "pushl %0\n\t"
  150. "popfl\n\t"
  151. "pushfl\n\t"
  152. "popl %0\n\t"
  153. "popfl\n\t"
  154. : "=&r" (f1), "=&r" (f2)
  155. : "ir" (flag));
  156. return ((f1^f2) & flag) != 0;
  157. }
  158. /* Probe for the CPUID instruction */
  159. static int __devinit have_cpuid_p(void)
  160. {
  161. return flag_is_changeable_p(X86_EFLAGS_ID);
  162. }
  163. /* Do minimum CPU detection early.
  164. Fields really needed: vendor, cpuid_level, family, model, mask, cache alignment.
  165. The others are not touched to avoid unwanted side effects.
  166. WARNING: this function is only called on the BP. Don't add code here
  167. that is supposed to run on all CPUs. */
  168. static void __init early_cpu_detect(void)
  169. {
  170. struct cpuinfo_x86 *c = &boot_cpu_data;
  171. c->x86_cache_alignment = 32;
  172. if (!have_cpuid_p())
  173. return;
  174. /* Get vendor name */
  175. cpuid(0x00000000, &c->cpuid_level,
  176. (int *)&c->x86_vendor_id[0],
  177. (int *)&c->x86_vendor_id[8],
  178. (int *)&c->x86_vendor_id[4]);
  179. get_cpu_vendor(c, 1);
  180. c->x86 = 4;
  181. if (c->cpuid_level >= 0x00000001) {
  182. u32 junk, tfms, cap0, misc;
  183. cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
  184. c->x86 = (tfms >> 8) & 15;
  185. c->x86_model = (tfms >> 4) & 15;
  186. if (c->x86 == 0xf)
  187. c->x86 += (tfms >> 20) & 0xff;
  188. if (c->x86 >= 0x6)
  189. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  190. c->x86_mask = tfms & 15;
  191. if (cap0 & (1<<19))
  192. c->x86_cache_alignment = ((misc >> 8) & 0xff) * 8;
  193. }
  194. }
  195. void __devinit generic_identify(struct cpuinfo_x86 * c)
  196. {
  197. u32 tfms, xlvl;
  198. int junk;
  199. if (have_cpuid_p()) {
  200. /* Get vendor name */
  201. cpuid(0x00000000, &c->cpuid_level,
  202. (int *)&c->x86_vendor_id[0],
  203. (int *)&c->x86_vendor_id[8],
  204. (int *)&c->x86_vendor_id[4]);
  205. get_cpu_vendor(c, 0);
  206. /* Initialize the standard set of capabilities */
  207. /* Note that the vendor-specific code below might override */
  208. /* Intel-defined flags: level 0x00000001 */
  209. if ( c->cpuid_level >= 0x00000001 ) {
  210. u32 capability, excap;
  211. cpuid(0x00000001, &tfms, &junk, &excap, &capability);
  212. c->x86_capability[0] = capability;
  213. c->x86_capability[4] = excap;
  214. c->x86 = (tfms >> 8) & 15;
  215. c->x86_model = (tfms >> 4) & 15;
  216. if (c->x86 == 0xf) {
  217. c->x86 += (tfms >> 20) & 0xff;
  218. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  219. }
  220. c->x86_mask = tfms & 15;
  221. } else {
  222. /* Have CPUID level 0 only - unheard of */
  223. c->x86 = 4;
  224. }
  225. /* AMD-defined flags: level 0x80000001 */
  226. xlvl = cpuid_eax(0x80000000);
  227. if ( (xlvl & 0xffff0000) == 0x80000000 ) {
  228. if ( xlvl >= 0x80000001 ) {
  229. c->x86_capability[1] = cpuid_edx(0x80000001);
  230. c->x86_capability[6] = cpuid_ecx(0x80000001);
  231. }
  232. if ( xlvl >= 0x80000004 )
  233. get_model_name(c); /* Default name */
  234. }
  235. }
  236. early_intel_workaround(c);
  237. #ifdef CONFIG_X86_HT
  238. phys_proc_id[smp_processor_id()] = (cpuid_ebx(1) >> 24) & 0xff;
  239. #endif
  240. }
  241. static void __devinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  242. {
  243. if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr ) {
  244. /* Disable processor serial number */
  245. unsigned long lo,hi;
  246. rdmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  247. lo |= 0x200000;
  248. wrmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  249. printk(KERN_NOTICE "CPU serial number disabled.\n");
  250. clear_bit(X86_FEATURE_PN, c->x86_capability);
  251. /* Disabling the serial number may affect the cpuid level */
  252. c->cpuid_level = cpuid_eax(0);
  253. }
  254. }
  255. static int __init x86_serial_nr_setup(char *s)
  256. {
  257. disable_x86_serial_nr = 0;
  258. return 1;
  259. }
  260. __setup("serialnumber", x86_serial_nr_setup);
  261. /*
  262. * This does the hard work of actually picking apart the CPU stuff...
  263. */
  264. void __devinit identify_cpu(struct cpuinfo_x86 *c)
  265. {
  266. int i;
  267. c->loops_per_jiffy = loops_per_jiffy;
  268. c->x86_cache_size = -1;
  269. c->x86_vendor = X86_VENDOR_UNKNOWN;
  270. c->cpuid_level = -1; /* CPUID not detected */
  271. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  272. c->x86_vendor_id[0] = '\0'; /* Unset */
  273. c->x86_model_id[0] = '\0'; /* Unset */
  274. c->x86_max_cores = 1;
  275. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  276. if (!have_cpuid_p()) {
  277. /* First of all, decide if this is a 486 or higher */
  278. /* It's a 486 if we can modify the AC flag */
  279. if ( flag_is_changeable_p(X86_EFLAGS_AC) )
  280. c->x86 = 4;
  281. else
  282. c->x86 = 3;
  283. }
  284. generic_identify(c);
  285. printk(KERN_DEBUG "CPU: After generic identify, caps:");
  286. for (i = 0; i < NCAPINTS; i++)
  287. printk(" %08lx", c->x86_capability[i]);
  288. printk("\n");
  289. if (this_cpu->c_identify) {
  290. this_cpu->c_identify(c);
  291. printk(KERN_DEBUG "CPU: After vendor identify, caps:");
  292. for (i = 0; i < NCAPINTS; i++)
  293. printk(" %08lx", c->x86_capability[i]);
  294. printk("\n");
  295. }
  296. /*
  297. * Vendor-specific initialization. In this section we
  298. * canonicalize the feature flags, meaning if there are
  299. * features a certain CPU supports which CPUID doesn't
  300. * tell us, CPUID claiming incorrect flags, or other bugs,
  301. * we handle them here.
  302. *
  303. * At the end of this section, c->x86_capability better
  304. * indicate the features this CPU genuinely supports!
  305. */
  306. if (this_cpu->c_init)
  307. this_cpu->c_init(c);
  308. /* Disable the PN if appropriate */
  309. squash_the_stupid_serial_number(c);
  310. /*
  311. * The vendor-specific functions might have changed features. Now
  312. * we do "generic changes."
  313. */
  314. /* TSC disabled? */
  315. if ( tsc_disable )
  316. clear_bit(X86_FEATURE_TSC, c->x86_capability);
  317. /* FXSR disabled? */
  318. if (disable_x86_fxsr) {
  319. clear_bit(X86_FEATURE_FXSR, c->x86_capability);
  320. clear_bit(X86_FEATURE_XMM, c->x86_capability);
  321. }
  322. if (disable_pse)
  323. clear_bit(X86_FEATURE_PSE, c->x86_capability);
  324. /* If the model name is still unset, do table lookup. */
  325. if ( !c->x86_model_id[0] ) {
  326. char *p;
  327. p = table_lookup_model(c);
  328. if ( p )
  329. strcpy(c->x86_model_id, p);
  330. else
  331. /* Last resort... */
  332. sprintf(c->x86_model_id, "%02x/%02x",
  333. c->x86_vendor, c->x86_model);
  334. }
  335. /* Now the feature flags better reflect actual CPU features! */
  336. printk(KERN_DEBUG "CPU: After all inits, caps:");
  337. for (i = 0; i < NCAPINTS; i++)
  338. printk(" %08lx", c->x86_capability[i]);
  339. printk("\n");
  340. /*
  341. * On SMP, boot_cpu_data holds the common feature set between
  342. * all CPUs; so make sure that we indicate which features are
  343. * common between the CPUs. The first time this routine gets
  344. * executed, c == &boot_cpu_data.
  345. */
  346. if ( c != &boot_cpu_data ) {
  347. /* AND the already accumulated flags with these */
  348. for ( i = 0 ; i < NCAPINTS ; i++ )
  349. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  350. }
  351. /* Init Machine Check Exception if available. */
  352. mcheck_init(c);
  353. if (c == &boot_cpu_data)
  354. sysenter_setup();
  355. enable_sep_cpu();
  356. if (c == &boot_cpu_data)
  357. mtrr_bp_init();
  358. else
  359. mtrr_ap_init();
  360. }
  361. #ifdef CONFIG_X86_HT
  362. void __devinit detect_ht(struct cpuinfo_x86 *c)
  363. {
  364. u32 eax, ebx, ecx, edx;
  365. int index_msb, core_bits;
  366. int cpu = smp_processor_id();
  367. cpuid(1, &eax, &ebx, &ecx, &edx);
  368. c->apicid = phys_pkg_id((ebx >> 24) & 0xFF, 0);
  369. if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
  370. return;
  371. smp_num_siblings = (ebx & 0xff0000) >> 16;
  372. if (smp_num_siblings == 1) {
  373. printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
  374. } else if (smp_num_siblings > 1 ) {
  375. if (smp_num_siblings > NR_CPUS) {
  376. printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
  377. smp_num_siblings = 1;
  378. return;
  379. }
  380. index_msb = get_count_order(smp_num_siblings);
  381. phys_proc_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
  382. printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
  383. phys_proc_id[cpu]);
  384. smp_num_siblings = smp_num_siblings / c->x86_max_cores;
  385. index_msb = get_count_order(smp_num_siblings) ;
  386. core_bits = get_count_order(c->x86_max_cores);
  387. cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb) &
  388. ((1 << core_bits) - 1);
  389. if (c->x86_max_cores > 1)
  390. printk(KERN_INFO "CPU: Processor Core ID: %d\n",
  391. cpu_core_id[cpu]);
  392. }
  393. }
  394. #endif
  395. void __devinit print_cpu_info(struct cpuinfo_x86 *c)
  396. {
  397. char *vendor = NULL;
  398. if (c->x86_vendor < X86_VENDOR_NUM)
  399. vendor = this_cpu->c_vendor;
  400. else if (c->cpuid_level >= 0)
  401. vendor = c->x86_vendor_id;
  402. if (vendor && strncmp(c->x86_model_id, vendor, strlen(vendor)))
  403. printk("%s ", vendor);
  404. if (!c->x86_model_id[0])
  405. printk("%d86", c->x86);
  406. else
  407. printk("%s", c->x86_model_id);
  408. if (c->x86_mask || c->cpuid_level >= 0)
  409. printk(" stepping %02x\n", c->x86_mask);
  410. else
  411. printk("\n");
  412. }
  413. cpumask_t cpu_initialized __devinitdata = CPU_MASK_NONE;
  414. /* This is hacky. :)
  415. * We're emulating future behavior.
  416. * In the future, the cpu-specific init functions will be called implicitly
  417. * via the magic of initcalls.
  418. * They will insert themselves into the cpu_devs structure.
  419. * Then, when cpu_init() is called, we can just iterate over that array.
  420. */
  421. extern int intel_cpu_init(void);
  422. extern int cyrix_init_cpu(void);
  423. extern int nsc_init_cpu(void);
  424. extern int amd_init_cpu(void);
  425. extern int centaur_init_cpu(void);
  426. extern int transmeta_init_cpu(void);
  427. extern int rise_init_cpu(void);
  428. extern int nexgen_init_cpu(void);
  429. extern int umc_init_cpu(void);
  430. void __init early_cpu_init(void)
  431. {
  432. intel_cpu_init();
  433. cyrix_init_cpu();
  434. nsc_init_cpu();
  435. amd_init_cpu();
  436. centaur_init_cpu();
  437. transmeta_init_cpu();
  438. rise_init_cpu();
  439. nexgen_init_cpu();
  440. umc_init_cpu();
  441. early_cpu_detect();
  442. #ifdef CONFIG_DEBUG_PAGEALLOC
  443. /* pse is not compatible with on-the-fly unmapping,
  444. * disable it even if the cpus claim to support it.
  445. */
  446. clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability);
  447. disable_pse = 1;
  448. #endif
  449. }
  450. /*
  451. * cpu_init() initializes state that is per-CPU. Some data is already
  452. * initialized (naturally) in the bootstrap process, such as the GDT
  453. * and IDT. We reload them nevertheless, this function acts as a
  454. * 'CPU state barrier', nothing should get across.
  455. */
  456. void __devinit cpu_init(void)
  457. {
  458. int cpu = smp_processor_id();
  459. struct tss_struct * t = &per_cpu(init_tss, cpu);
  460. struct thread_struct *thread = &current->thread;
  461. struct desc_struct *gdt = get_cpu_gdt_table(cpu);
  462. __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
  463. if (cpu_test_and_set(cpu, cpu_initialized)) {
  464. printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
  465. for (;;) local_irq_enable();
  466. }
  467. printk(KERN_INFO "Initializing CPU#%d\n", cpu);
  468. if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
  469. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  470. if (tsc_disable && cpu_has_tsc) {
  471. printk(KERN_NOTICE "Disabling TSC...\n");
  472. /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
  473. clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
  474. set_in_cr4(X86_CR4_TSD);
  475. }
  476. /*
  477. * Initialize the per-CPU GDT with the boot GDT,
  478. * and set up the GDT descriptor:
  479. */
  480. memcpy(gdt, cpu_gdt_table, GDT_SIZE);
  481. /* Set up GDT entry for 16bit stack */
  482. *(__u64 *)(&gdt[GDT_ENTRY_ESPFIX_SS]) |=
  483. ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
  484. ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
  485. (CPU_16BIT_STACK_SIZE - 1);
  486. cpu_gdt_descr[cpu].size = GDT_SIZE - 1;
  487. cpu_gdt_descr[cpu].address = (unsigned long)gdt;
  488. load_gdt(&cpu_gdt_descr[cpu]);
  489. load_idt(&idt_descr);
  490. /*
  491. * Set up and load the per-CPU TSS and LDT
  492. */
  493. atomic_inc(&init_mm.mm_count);
  494. current->active_mm = &init_mm;
  495. if (current->mm)
  496. BUG();
  497. enter_lazy_tlb(&init_mm, current);
  498. load_esp0(t, thread);
  499. set_tss_desc(cpu,t);
  500. load_TR_desc();
  501. load_LDT(&init_mm.context);
  502. #ifdef CONFIG_DOUBLEFAULT
  503. /* Set up doublefault TSS pointer in the GDT */
  504. __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
  505. #endif
  506. /* Clear %fs and %gs. */
  507. asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
  508. /* Clear all 6 debug registers: */
  509. set_debugreg(0, 0);
  510. set_debugreg(0, 1);
  511. set_debugreg(0, 2);
  512. set_debugreg(0, 3);
  513. set_debugreg(0, 6);
  514. set_debugreg(0, 7);
  515. /*
  516. * Force FPU initialization:
  517. */
  518. current_thread_info()->status = 0;
  519. clear_used_math();
  520. mxcsr_feature_mask_init();
  521. }
  522. #ifdef CONFIG_HOTPLUG_CPU
  523. void __devinit cpu_uninit(void)
  524. {
  525. int cpu = raw_smp_processor_id();
  526. cpu_clear(cpu, cpu_initialized);
  527. /* lazy TLB state */
  528. per_cpu(cpu_tlbstate, cpu).state = 0;
  529. per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm;
  530. }
  531. #endif