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. .c_vendor = "Unknown",
  41. };
  42. static struct cpu_dev * this_cpu = &default_cpu;
  43. static int __init cachesize_setup(char *str)
  44. {
  45. get_option (&str, &cachesize_override);
  46. return 1;
  47. }
  48. __setup("cachesize=", cachesize_setup);
  49. int __devinit get_model_name(struct cpuinfo_x86 *c)
  50. {
  51. unsigned int *v;
  52. char *p, *q;
  53. if (cpuid_eax(0x80000000) < 0x80000004)
  54. return 0;
  55. v = (unsigned int *) c->x86_model_id;
  56. cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
  57. cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
  58. cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
  59. c->x86_model_id[48] = 0;
  60. /* Intel chips right-justify this string for some dumb reason;
  61. undo that brain damage */
  62. p = q = &c->x86_model_id[0];
  63. while ( *p == ' ' )
  64. p++;
  65. if ( p != q ) {
  66. while ( *p )
  67. *q++ = *p++;
  68. while ( q <= &c->x86_model_id[48] )
  69. *q++ = '\0'; /* Zero-pad the rest */
  70. }
  71. return 1;
  72. }
  73. void __devinit display_cacheinfo(struct cpuinfo_x86 *c)
  74. {
  75. unsigned int n, dummy, ecx, edx, l2size;
  76. n = cpuid_eax(0x80000000);
  77. if (n >= 0x80000005) {
  78. cpuid(0x80000005, &dummy, &dummy, &ecx, &edx);
  79. printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
  80. edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
  81. c->x86_cache_size=(ecx>>24)+(edx>>24);
  82. }
  83. if (n < 0x80000006) /* Some chips just has a large L1. */
  84. return;
  85. ecx = cpuid_ecx(0x80000006);
  86. l2size = ecx >> 16;
  87. /* do processor-specific cache resizing */
  88. if (this_cpu->c_size_cache)
  89. l2size = this_cpu->c_size_cache(c,l2size);
  90. /* Allow user to override all this if necessary. */
  91. if (cachesize_override != -1)
  92. l2size = cachesize_override;
  93. if ( l2size == 0 )
  94. return; /* Again, no L2 cache is possible */
  95. c->x86_cache_size = l2size;
  96. printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
  97. l2size, ecx & 0xFF);
  98. }
  99. /* Naming convention should be: <Name> [(<Codename>)] */
  100. /* This table only is used unless init_<vendor>() below doesn't set it; */
  101. /* in particular, if CPUID levels 0x80000002..4 are supported, this isn't used */
  102. /* Look up CPU names by table lookup. */
  103. static char __devinit *table_lookup_model(struct cpuinfo_x86 *c)
  104. {
  105. struct cpu_model_info *info;
  106. if ( c->x86_model >= 16 )
  107. return NULL; /* Range check */
  108. if (!this_cpu)
  109. return NULL;
  110. info = this_cpu->c_models;
  111. while (info && info->family) {
  112. if (info->family == c->x86)
  113. return info->model_names[c->x86_model];
  114. info++;
  115. }
  116. return NULL; /* Not found */
  117. }
  118. static void __devinit get_cpu_vendor(struct cpuinfo_x86 *c, int early)
  119. {
  120. char *v = c->x86_vendor_id;
  121. int i;
  122. static int printed;
  123. for (i = 0; i < X86_VENDOR_NUM; i++) {
  124. if (cpu_devs[i]) {
  125. if (!strcmp(v,cpu_devs[i]->c_ident[0]) ||
  126. (cpu_devs[i]->c_ident[1] &&
  127. !strcmp(v,cpu_devs[i]->c_ident[1]))) {
  128. c->x86_vendor = i;
  129. if (!early)
  130. this_cpu = cpu_devs[i];
  131. return;
  132. }
  133. }
  134. }
  135. if (!printed) {
  136. printed++;
  137. printk(KERN_ERR "CPU: Vendor unknown, using generic init.\n");
  138. printk(KERN_ERR "CPU: Your system may be unstable.\n");
  139. }
  140. c->x86_vendor = X86_VENDOR_UNKNOWN;
  141. this_cpu = &default_cpu;
  142. }
  143. static int __init x86_fxsr_setup(char * s)
  144. {
  145. disable_x86_fxsr = 1;
  146. return 1;
  147. }
  148. __setup("nofxsr", x86_fxsr_setup);
  149. /* Standard macro to see if a specific flag is changeable */
  150. static inline int flag_is_changeable_p(u32 flag)
  151. {
  152. u32 f1, f2;
  153. asm("pushfl\n\t"
  154. "pushfl\n\t"
  155. "popl %0\n\t"
  156. "movl %0,%1\n\t"
  157. "xorl %2,%0\n\t"
  158. "pushl %0\n\t"
  159. "popfl\n\t"
  160. "pushfl\n\t"
  161. "popl %0\n\t"
  162. "popfl\n\t"
  163. : "=&r" (f1), "=&r" (f2)
  164. : "ir" (flag));
  165. return ((f1^f2) & flag) != 0;
  166. }
  167. /* Probe for the CPUID instruction */
  168. static int __devinit have_cpuid_p(void)
  169. {
  170. return flag_is_changeable_p(X86_EFLAGS_ID);
  171. }
  172. /* Do minimum CPU detection early.
  173. Fields really needed: vendor, cpuid_level, family, model, mask, cache alignment.
  174. The others are not touched to avoid unwanted side effects.
  175. WARNING: this function is only called on the BP. Don't add code here
  176. that is supposed to run on all CPUs. */
  177. static void __init early_cpu_detect(void)
  178. {
  179. struct cpuinfo_x86 *c = &boot_cpu_data;
  180. c->x86_cache_alignment = 32;
  181. if (!have_cpuid_p())
  182. return;
  183. /* Get vendor name */
  184. cpuid(0x00000000, &c->cpuid_level,
  185. (int *)&c->x86_vendor_id[0],
  186. (int *)&c->x86_vendor_id[8],
  187. (int *)&c->x86_vendor_id[4]);
  188. get_cpu_vendor(c, 1);
  189. c->x86 = 4;
  190. if (c->cpuid_level >= 0x00000001) {
  191. u32 junk, tfms, cap0, misc;
  192. cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
  193. c->x86 = (tfms >> 8) & 15;
  194. c->x86_model = (tfms >> 4) & 15;
  195. if (c->x86 == 0xf)
  196. c->x86 += (tfms >> 20) & 0xff;
  197. if (c->x86 >= 0x6)
  198. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  199. c->x86_mask = tfms & 15;
  200. if (cap0 & (1<<19))
  201. c->x86_cache_alignment = ((misc >> 8) & 0xff) * 8;
  202. }
  203. }
  204. void __devinit generic_identify(struct cpuinfo_x86 * c)
  205. {
  206. u32 tfms, xlvl;
  207. int junk;
  208. if (have_cpuid_p()) {
  209. /* Get vendor name */
  210. cpuid(0x00000000, &c->cpuid_level,
  211. (int *)&c->x86_vendor_id[0],
  212. (int *)&c->x86_vendor_id[8],
  213. (int *)&c->x86_vendor_id[4]);
  214. get_cpu_vendor(c, 0);
  215. /* Initialize the standard set of capabilities */
  216. /* Note that the vendor-specific code below might override */
  217. /* Intel-defined flags: level 0x00000001 */
  218. if ( c->cpuid_level >= 0x00000001 ) {
  219. u32 capability, excap;
  220. cpuid(0x00000001, &tfms, &junk, &excap, &capability);
  221. c->x86_capability[0] = capability;
  222. c->x86_capability[4] = excap;
  223. c->x86 = (tfms >> 8) & 15;
  224. c->x86_model = (tfms >> 4) & 15;
  225. if (c->x86 == 0xf) {
  226. c->x86 += (tfms >> 20) & 0xff;
  227. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  228. }
  229. c->x86_mask = tfms & 15;
  230. } else {
  231. /* Have CPUID level 0 only - unheard of */
  232. c->x86 = 4;
  233. }
  234. /* AMD-defined flags: level 0x80000001 */
  235. xlvl = cpuid_eax(0x80000000);
  236. if ( (xlvl & 0xffff0000) == 0x80000000 ) {
  237. if ( xlvl >= 0x80000001 ) {
  238. c->x86_capability[1] = cpuid_edx(0x80000001);
  239. c->x86_capability[6] = cpuid_ecx(0x80000001);
  240. }
  241. if ( xlvl >= 0x80000004 )
  242. get_model_name(c); /* Default name */
  243. }
  244. }
  245. early_intel_workaround(c);
  246. #ifdef CONFIG_X86_HT
  247. phys_proc_id[smp_processor_id()] = (cpuid_ebx(1) >> 24) & 0xff;
  248. #endif
  249. }
  250. static void __devinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  251. {
  252. if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr ) {
  253. /* Disable processor serial number */
  254. unsigned long lo,hi;
  255. rdmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  256. lo |= 0x200000;
  257. wrmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  258. printk(KERN_NOTICE "CPU serial number disabled.\n");
  259. clear_bit(X86_FEATURE_PN, c->x86_capability);
  260. /* Disabling the serial number may affect the cpuid level */
  261. c->cpuid_level = cpuid_eax(0);
  262. }
  263. }
  264. static int __init x86_serial_nr_setup(char *s)
  265. {
  266. disable_x86_serial_nr = 0;
  267. return 1;
  268. }
  269. __setup("serialnumber", x86_serial_nr_setup);
  270. /*
  271. * This does the hard work of actually picking apart the CPU stuff...
  272. */
  273. void __devinit identify_cpu(struct cpuinfo_x86 *c)
  274. {
  275. int i;
  276. c->loops_per_jiffy = loops_per_jiffy;
  277. c->x86_cache_size = -1;
  278. c->x86_vendor = X86_VENDOR_UNKNOWN;
  279. c->cpuid_level = -1; /* CPUID not detected */
  280. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  281. c->x86_vendor_id[0] = '\0'; /* Unset */
  282. c->x86_model_id[0] = '\0'; /* Unset */
  283. c->x86_max_cores = 1;
  284. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  285. if (!have_cpuid_p()) {
  286. /* First of all, decide if this is a 486 or higher */
  287. /* It's a 486 if we can modify the AC flag */
  288. if ( flag_is_changeable_p(X86_EFLAGS_AC) )
  289. c->x86 = 4;
  290. else
  291. c->x86 = 3;
  292. }
  293. generic_identify(c);
  294. printk(KERN_DEBUG "CPU: After generic identify, caps:");
  295. for (i = 0; i < NCAPINTS; i++)
  296. printk(" %08lx", c->x86_capability[i]);
  297. printk("\n");
  298. if (this_cpu->c_identify) {
  299. this_cpu->c_identify(c);
  300. printk(KERN_DEBUG "CPU: After vendor identify, caps:");
  301. for (i = 0; i < NCAPINTS; i++)
  302. printk(" %08lx", c->x86_capability[i]);
  303. printk("\n");
  304. }
  305. /*
  306. * Vendor-specific initialization. In this section we
  307. * canonicalize the feature flags, meaning if there are
  308. * features a certain CPU supports which CPUID doesn't
  309. * tell us, CPUID claiming incorrect flags, or other bugs,
  310. * we handle them here.
  311. *
  312. * At the end of this section, c->x86_capability better
  313. * indicate the features this CPU genuinely supports!
  314. */
  315. if (this_cpu->c_init)
  316. this_cpu->c_init(c);
  317. /* Disable the PN if appropriate */
  318. squash_the_stupid_serial_number(c);
  319. /*
  320. * The vendor-specific functions might have changed features. Now
  321. * we do "generic changes."
  322. */
  323. /* TSC disabled? */
  324. if ( tsc_disable )
  325. clear_bit(X86_FEATURE_TSC, c->x86_capability);
  326. /* FXSR disabled? */
  327. if (disable_x86_fxsr) {
  328. clear_bit(X86_FEATURE_FXSR, c->x86_capability);
  329. clear_bit(X86_FEATURE_XMM, c->x86_capability);
  330. }
  331. if (disable_pse)
  332. clear_bit(X86_FEATURE_PSE, c->x86_capability);
  333. /* If the model name is still unset, do table lookup. */
  334. if ( !c->x86_model_id[0] ) {
  335. char *p;
  336. p = table_lookup_model(c);
  337. if ( p )
  338. strcpy(c->x86_model_id, p);
  339. else
  340. /* Last resort... */
  341. sprintf(c->x86_model_id, "%02x/%02x",
  342. c->x86_vendor, c->x86_model);
  343. }
  344. /* Now the feature flags better reflect actual CPU features! */
  345. printk(KERN_DEBUG "CPU: After all inits, caps:");
  346. for (i = 0; i < NCAPINTS; i++)
  347. printk(" %08lx", c->x86_capability[i]);
  348. printk("\n");
  349. /*
  350. * On SMP, boot_cpu_data holds the common feature set between
  351. * all CPUs; so make sure that we indicate which features are
  352. * common between the CPUs. The first time this routine gets
  353. * executed, c == &boot_cpu_data.
  354. */
  355. if ( c != &boot_cpu_data ) {
  356. /* AND the already accumulated flags with these */
  357. for ( i = 0 ; i < NCAPINTS ; i++ )
  358. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  359. }
  360. /* Init Machine Check Exception if available. */
  361. mcheck_init(c);
  362. if (c == &boot_cpu_data)
  363. sysenter_setup();
  364. enable_sep_cpu();
  365. if (c == &boot_cpu_data)
  366. mtrr_bp_init();
  367. else
  368. mtrr_ap_init();
  369. }
  370. #ifdef CONFIG_X86_HT
  371. void __devinit detect_ht(struct cpuinfo_x86 *c)
  372. {
  373. u32 eax, ebx, ecx, edx;
  374. int index_msb, core_bits;
  375. int cpu = smp_processor_id();
  376. cpuid(1, &eax, &ebx, &ecx, &edx);
  377. c->apicid = phys_pkg_id((ebx >> 24) & 0xFF, 0);
  378. if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
  379. return;
  380. smp_num_siblings = (ebx & 0xff0000) >> 16;
  381. if (smp_num_siblings == 1) {
  382. printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
  383. } else if (smp_num_siblings > 1 ) {
  384. if (smp_num_siblings > NR_CPUS) {
  385. printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
  386. smp_num_siblings = 1;
  387. return;
  388. }
  389. index_msb = get_count_order(smp_num_siblings);
  390. phys_proc_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
  391. printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
  392. phys_proc_id[cpu]);
  393. smp_num_siblings = smp_num_siblings / c->x86_max_cores;
  394. index_msb = get_count_order(smp_num_siblings) ;
  395. core_bits = get_count_order(c->x86_max_cores);
  396. cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb) &
  397. ((1 << core_bits) - 1);
  398. if (c->x86_max_cores > 1)
  399. printk(KERN_INFO "CPU: Processor Core ID: %d\n",
  400. cpu_core_id[cpu]);
  401. }
  402. }
  403. #endif
  404. void __devinit print_cpu_info(struct cpuinfo_x86 *c)
  405. {
  406. char *vendor = NULL;
  407. if (c->x86_vendor < X86_VENDOR_NUM)
  408. vendor = this_cpu->c_vendor;
  409. else if (c->cpuid_level >= 0)
  410. vendor = c->x86_vendor_id;
  411. if (vendor && strncmp(c->x86_model_id, vendor, strlen(vendor)))
  412. printk("%s ", vendor);
  413. if (!c->x86_model_id[0])
  414. printk("%d86", c->x86);
  415. else
  416. printk("%s", c->x86_model_id);
  417. if (c->x86_mask || c->cpuid_level >= 0)
  418. printk(" stepping %02x\n", c->x86_mask);
  419. else
  420. printk("\n");
  421. }
  422. cpumask_t cpu_initialized __devinitdata = CPU_MASK_NONE;
  423. /* This is hacky. :)
  424. * We're emulating future behavior.
  425. * In the future, the cpu-specific init functions will be called implicitly
  426. * via the magic of initcalls.
  427. * They will insert themselves into the cpu_devs structure.
  428. * Then, when cpu_init() is called, we can just iterate over that array.
  429. */
  430. extern int intel_cpu_init(void);
  431. extern int cyrix_init_cpu(void);
  432. extern int nsc_init_cpu(void);
  433. extern int amd_init_cpu(void);
  434. extern int centaur_init_cpu(void);
  435. extern int transmeta_init_cpu(void);
  436. extern int rise_init_cpu(void);
  437. extern int nexgen_init_cpu(void);
  438. extern int umc_init_cpu(void);
  439. void __init early_cpu_init(void)
  440. {
  441. intel_cpu_init();
  442. cyrix_init_cpu();
  443. nsc_init_cpu();
  444. amd_init_cpu();
  445. centaur_init_cpu();
  446. transmeta_init_cpu();
  447. rise_init_cpu();
  448. nexgen_init_cpu();
  449. umc_init_cpu();
  450. early_cpu_detect();
  451. #ifdef CONFIG_DEBUG_PAGEALLOC
  452. /* pse is not compatible with on-the-fly unmapping,
  453. * disable it even if the cpus claim to support it.
  454. */
  455. clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability);
  456. disable_pse = 1;
  457. #endif
  458. }
  459. /*
  460. * cpu_init() initializes state that is per-CPU. Some data is already
  461. * initialized (naturally) in the bootstrap process, such as the GDT
  462. * and IDT. We reload them nevertheless, this function acts as a
  463. * 'CPU state barrier', nothing should get across.
  464. */
  465. void __devinit cpu_init(void)
  466. {
  467. int cpu = smp_processor_id();
  468. struct tss_struct * t = &per_cpu(init_tss, cpu);
  469. struct thread_struct *thread = &current->thread;
  470. struct desc_struct *gdt = get_cpu_gdt_table(cpu);
  471. __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
  472. if (cpu_test_and_set(cpu, cpu_initialized)) {
  473. printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
  474. for (;;) local_irq_enable();
  475. }
  476. printk(KERN_INFO "Initializing CPU#%d\n", cpu);
  477. if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
  478. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  479. if (tsc_disable && cpu_has_tsc) {
  480. printk(KERN_NOTICE "Disabling TSC...\n");
  481. /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
  482. clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
  483. set_in_cr4(X86_CR4_TSD);
  484. }
  485. /*
  486. * Initialize the per-CPU GDT with the boot GDT,
  487. * and set up the GDT descriptor:
  488. */
  489. memcpy(gdt, cpu_gdt_table, GDT_SIZE);
  490. /* Set up GDT entry for 16bit stack */
  491. *(__u64 *)(&gdt[GDT_ENTRY_ESPFIX_SS]) |=
  492. ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
  493. ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
  494. (CPU_16BIT_STACK_SIZE - 1);
  495. cpu_gdt_descr[cpu].size = GDT_SIZE - 1;
  496. cpu_gdt_descr[cpu].address = (unsigned long)gdt;
  497. load_gdt(&cpu_gdt_descr[cpu]);
  498. load_idt(&idt_descr);
  499. /*
  500. * Set up and load the per-CPU TSS and LDT
  501. */
  502. atomic_inc(&init_mm.mm_count);
  503. current->active_mm = &init_mm;
  504. if (current->mm)
  505. BUG();
  506. enter_lazy_tlb(&init_mm, current);
  507. load_esp0(t, thread);
  508. set_tss_desc(cpu,t);
  509. load_TR_desc();
  510. load_LDT(&init_mm.context);
  511. #ifdef CONFIG_DOUBLEFAULT
  512. /* Set up doublefault TSS pointer in the GDT */
  513. __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
  514. #endif
  515. /* Clear %fs and %gs. */
  516. asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
  517. /* Clear all 6 debug registers: */
  518. set_debugreg(0, 0);
  519. set_debugreg(0, 1);
  520. set_debugreg(0, 2);
  521. set_debugreg(0, 3);
  522. set_debugreg(0, 6);
  523. set_debugreg(0, 7);
  524. /*
  525. * Force FPU initialization:
  526. */
  527. current_thread_info()->status = 0;
  528. clear_used_math();
  529. mxcsr_feature_mask_init();
  530. }
  531. #ifdef CONFIG_HOTPLUG_CPU
  532. void __devinit cpu_uninit(void)
  533. {
  534. int cpu = raw_smp_processor_id();
  535. cpu_clear(cpu, cpu_initialized);
  536. /* lazy TLB state */
  537. per_cpu(cpu_tlbstate, cpu).state = 0;
  538. per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm;
  539. }
  540. #endif