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 __devinitdata = -1;
  24. static int disable_x86_fxsr __devinitdata = 0;
  25. static int disable_x86_serial_nr __devinitdata = 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 __devinit 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 __devinit 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 __devinit *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 __devinit 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 __devinit 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. #ifdef CONFIG_X86_HT
  197. phys_proc_id[smp_processor_id()] = (cpuid_ebx(1) >> 24) & 0xff;
  198. #endif
  199. }
  200. void __devinit generic_identify(struct cpuinfo_x86 * c)
  201. {
  202. u32 tfms, xlvl;
  203. int junk;
  204. if (have_cpuid_p()) {
  205. /* Get vendor name */
  206. cpuid(0x00000000, &c->cpuid_level,
  207. (int *)&c->x86_vendor_id[0],
  208. (int *)&c->x86_vendor_id[8],
  209. (int *)&c->x86_vendor_id[4]);
  210. get_cpu_vendor(c, 0);
  211. /* Initialize the standard set of capabilities */
  212. /* Note that the vendor-specific code below might override */
  213. /* Intel-defined flags: level 0x00000001 */
  214. if ( c->cpuid_level >= 0x00000001 ) {
  215. u32 capability, excap;
  216. cpuid(0x00000001, &tfms, &junk, &excap, &capability);
  217. c->x86_capability[0] = capability;
  218. c->x86_capability[4] = excap;
  219. c->x86 = (tfms >> 8) & 15;
  220. c->x86_model = (tfms >> 4) & 15;
  221. if (c->x86 == 0xf) {
  222. c->x86 += (tfms >> 20) & 0xff;
  223. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  224. }
  225. c->x86_mask = tfms & 15;
  226. } else {
  227. /* Have CPUID level 0 only - unheard of */
  228. c->x86 = 4;
  229. }
  230. /* AMD-defined flags: level 0x80000001 */
  231. xlvl = cpuid_eax(0x80000000);
  232. if ( (xlvl & 0xffff0000) == 0x80000000 ) {
  233. if ( xlvl >= 0x80000001 ) {
  234. c->x86_capability[1] = cpuid_edx(0x80000001);
  235. c->x86_capability[6] = cpuid_ecx(0x80000001);
  236. }
  237. if ( xlvl >= 0x80000004 )
  238. get_model_name(c); /* Default name */
  239. }
  240. }
  241. }
  242. static void __devinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
  243. {
  244. if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr ) {
  245. /* Disable processor serial number */
  246. unsigned long lo,hi;
  247. rdmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  248. lo |= 0x200000;
  249. wrmsr(MSR_IA32_BBL_CR_CTL,lo,hi);
  250. printk(KERN_NOTICE "CPU serial number disabled.\n");
  251. clear_bit(X86_FEATURE_PN, c->x86_capability);
  252. /* Disabling the serial number may affect the cpuid level */
  253. c->cpuid_level = cpuid_eax(0);
  254. }
  255. }
  256. static int __init x86_serial_nr_setup(char *s)
  257. {
  258. disable_x86_serial_nr = 0;
  259. return 1;
  260. }
  261. __setup("serialnumber", x86_serial_nr_setup);
  262. /*
  263. * This does the hard work of actually picking apart the CPU stuff...
  264. */
  265. void __devinit identify_cpu(struct cpuinfo_x86 *c)
  266. {
  267. int i;
  268. c->loops_per_jiffy = loops_per_jiffy;
  269. c->x86_cache_size = -1;
  270. c->x86_vendor = X86_VENDOR_UNKNOWN;
  271. c->cpuid_level = -1; /* CPUID not detected */
  272. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  273. c->x86_vendor_id[0] = '\0'; /* Unset */
  274. c->x86_model_id[0] = '\0'; /* Unset */
  275. c->x86_num_cores = 1;
  276. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  277. if (!have_cpuid_p()) {
  278. /* First of all, decide if this is a 486 or higher */
  279. /* It's a 486 if we can modify the AC flag */
  280. if ( flag_is_changeable_p(X86_EFLAGS_AC) )
  281. c->x86 = 4;
  282. else
  283. c->x86 = 3;
  284. }
  285. generic_identify(c);
  286. printk(KERN_DEBUG "CPU: After generic identify, caps:");
  287. for (i = 0; i < NCAPINTS; i++)
  288. printk(" %08lx", c->x86_capability[i]);
  289. printk("\n");
  290. if (this_cpu->c_identify) {
  291. this_cpu->c_identify(c);
  292. printk(KERN_DEBUG "CPU: After vendor identify, caps:");
  293. for (i = 0; i < NCAPINTS; i++)
  294. printk(" %08lx", c->x86_capability[i]);
  295. printk("\n");
  296. }
  297. /*
  298. * Vendor-specific initialization. In this section we
  299. * canonicalize the feature flags, meaning if there are
  300. * features a certain CPU supports which CPUID doesn't
  301. * tell us, CPUID claiming incorrect flags, or other bugs,
  302. * we handle them here.
  303. *
  304. * At the end of this section, c->x86_capability better
  305. * indicate the features this CPU genuinely supports!
  306. */
  307. if (this_cpu->c_init)
  308. this_cpu->c_init(c);
  309. /* Disable the PN if appropriate */
  310. squash_the_stupid_serial_number(c);
  311. /*
  312. * The vendor-specific functions might have changed features. Now
  313. * we do "generic changes."
  314. */
  315. /* TSC disabled? */
  316. if ( tsc_disable )
  317. clear_bit(X86_FEATURE_TSC, c->x86_capability);
  318. /* FXSR disabled? */
  319. if (disable_x86_fxsr) {
  320. clear_bit(X86_FEATURE_FXSR, c->x86_capability);
  321. clear_bit(X86_FEATURE_XMM, c->x86_capability);
  322. }
  323. if (disable_pse)
  324. clear_bit(X86_FEATURE_PSE, c->x86_capability);
  325. /* If the model name is still unset, do table lookup. */
  326. if ( !c->x86_model_id[0] ) {
  327. char *p;
  328. p = table_lookup_model(c);
  329. if ( p )
  330. strcpy(c->x86_model_id, p);
  331. else
  332. /* Last resort... */
  333. sprintf(c->x86_model_id, "%02x/%02x",
  334. c->x86_vendor, c->x86_model);
  335. }
  336. /* Now the feature flags better reflect actual CPU features! */
  337. printk(KERN_DEBUG "CPU: After all inits, caps:");
  338. for (i = 0; i < NCAPINTS; i++)
  339. printk(" %08lx", c->x86_capability[i]);
  340. printk("\n");
  341. /*
  342. * On SMP, boot_cpu_data holds the common feature set between
  343. * all CPUs; so make sure that we indicate which features are
  344. * common between the CPUs. The first time this routine gets
  345. * executed, c == &boot_cpu_data.
  346. */
  347. if ( c != &boot_cpu_data ) {
  348. /* AND the already accumulated flags with these */
  349. for ( i = 0 ; i < NCAPINTS ; i++ )
  350. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  351. }
  352. /* Init Machine Check Exception if available. */
  353. #ifdef CONFIG_X86_MCE
  354. mcheck_init(c);
  355. #endif
  356. if (c == &boot_cpu_data)
  357. sysenter_setup();
  358. enable_sep_cpu();
  359. if (c == &boot_cpu_data)
  360. mtrr_bp_init();
  361. else
  362. mtrr_ap_init();
  363. }
  364. #ifdef CONFIG_X86_HT
  365. void __devinit detect_ht(struct cpuinfo_x86 *c)
  366. {
  367. u32 eax, ebx, ecx, edx;
  368. int index_msb, tmp;
  369. int cpu = smp_processor_id();
  370. if (!cpu_has(c, X86_FEATURE_HT) || cpu_has(c, X86_FEATURE_CMP_LEGACY))
  371. return;
  372. cpuid(1, &eax, &ebx, &ecx, &edx);
  373. smp_num_siblings = (ebx & 0xff0000) >> 16;
  374. if (smp_num_siblings == 1) {
  375. printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
  376. } else if (smp_num_siblings > 1 ) {
  377. index_msb = 31;
  378. if (smp_num_siblings > NR_CPUS) {
  379. printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
  380. smp_num_siblings = 1;
  381. return;
  382. }
  383. tmp = smp_num_siblings;
  384. while ((tmp & 0x80000000 ) == 0) {
  385. tmp <<=1 ;
  386. index_msb--;
  387. }
  388. if (smp_num_siblings & (smp_num_siblings - 1))
  389. index_msb++;
  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_num_cores;
  394. tmp = smp_num_siblings;
  395. index_msb = 31;
  396. while ((tmp & 0x80000000) == 0) {
  397. tmp <<=1 ;
  398. index_msb--;
  399. }
  400. if (smp_num_siblings & (smp_num_siblings - 1))
  401. index_msb++;
  402. cpu_core_id[cpu] = phys_pkg_id((ebx >> 24) & 0xFF, index_msb);
  403. if (c->x86_num_cores > 1)
  404. printk(KERN_INFO "CPU: Processor Core ID: %d\n",
  405. cpu_core_id[cpu]);
  406. }
  407. }
  408. #endif
  409. void __devinit print_cpu_info(struct cpuinfo_x86 *c)
  410. {
  411. char *vendor = NULL;
  412. if (c->x86_vendor < X86_VENDOR_NUM)
  413. vendor = this_cpu->c_vendor;
  414. else if (c->cpuid_level >= 0)
  415. vendor = c->x86_vendor_id;
  416. if (vendor && strncmp(c->x86_model_id, vendor, strlen(vendor)))
  417. printk("%s ", vendor);
  418. if (!c->x86_model_id[0])
  419. printk("%d86", c->x86);
  420. else
  421. printk("%s", c->x86_model_id);
  422. if (c->x86_mask || c->cpuid_level >= 0)
  423. printk(" stepping %02x\n", c->x86_mask);
  424. else
  425. printk("\n");
  426. }
  427. cpumask_t cpu_initialized __devinitdata = CPU_MASK_NONE;
  428. /* This is hacky. :)
  429. * We're emulating future behavior.
  430. * In the future, the cpu-specific init functions will be called implicitly
  431. * via the magic of initcalls.
  432. * They will insert themselves into the cpu_devs structure.
  433. * Then, when cpu_init() is called, we can just iterate over that array.
  434. */
  435. extern int intel_cpu_init(void);
  436. extern int cyrix_init_cpu(void);
  437. extern int nsc_init_cpu(void);
  438. extern int amd_init_cpu(void);
  439. extern int centaur_init_cpu(void);
  440. extern int transmeta_init_cpu(void);
  441. extern int rise_init_cpu(void);
  442. extern int nexgen_init_cpu(void);
  443. extern int umc_init_cpu(void);
  444. void __init early_cpu_init(void)
  445. {
  446. intel_cpu_init();
  447. cyrix_init_cpu();
  448. nsc_init_cpu();
  449. amd_init_cpu();
  450. centaur_init_cpu();
  451. transmeta_init_cpu();
  452. rise_init_cpu();
  453. nexgen_init_cpu();
  454. umc_init_cpu();
  455. early_cpu_detect();
  456. #ifdef CONFIG_DEBUG_PAGEALLOC
  457. /* pse is not compatible with on-the-fly unmapping,
  458. * disable it even if the cpus claim to support it.
  459. */
  460. clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability);
  461. disable_pse = 1;
  462. #endif
  463. }
  464. /*
  465. * cpu_init() initializes state that is per-CPU. Some data is already
  466. * initialized (naturally) in the bootstrap process, such as the GDT
  467. * and IDT. We reload them nevertheless, this function acts as a
  468. * 'CPU state barrier', nothing should get across.
  469. */
  470. void __devinit cpu_init(void)
  471. {
  472. int cpu = smp_processor_id();
  473. struct tss_struct * t = &per_cpu(init_tss, cpu);
  474. struct thread_struct *thread = &current->thread;
  475. __u32 stk16_off = (__u32)&per_cpu(cpu_16bit_stack, cpu);
  476. if (cpu_test_and_set(cpu, cpu_initialized)) {
  477. printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
  478. for (;;) local_irq_enable();
  479. }
  480. printk(KERN_INFO "Initializing CPU#%d\n", cpu);
  481. if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
  482. clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
  483. if (tsc_disable && cpu_has_tsc) {
  484. printk(KERN_NOTICE "Disabling TSC...\n");
  485. /**** FIX-HPA: DOES THIS REALLY BELONG HERE? ****/
  486. clear_bit(X86_FEATURE_TSC, boot_cpu_data.x86_capability);
  487. set_in_cr4(X86_CR4_TSD);
  488. }
  489. /*
  490. * Initialize the per-CPU GDT with the boot GDT,
  491. * and set up the GDT descriptor:
  492. */
  493. memcpy(&per_cpu(cpu_gdt_table, cpu), cpu_gdt_table,
  494. GDT_SIZE);
  495. /* Set up GDT entry for 16bit stack */
  496. *(__u64 *)&(per_cpu(cpu_gdt_table, cpu)[GDT_ENTRY_ESPFIX_SS]) |=
  497. ((((__u64)stk16_off) << 16) & 0x000000ffffff0000ULL) |
  498. ((((__u64)stk16_off) << 32) & 0xff00000000000000ULL) |
  499. (CPU_16BIT_STACK_SIZE - 1);
  500. cpu_gdt_descr[cpu].size = GDT_SIZE - 1;
  501. cpu_gdt_descr[cpu].address =
  502. (unsigned long)&per_cpu(cpu_gdt_table, cpu);
  503. /*
  504. * Set up the per-thread TLS descriptor cache:
  505. */
  506. memcpy(thread->tls_array, &per_cpu(cpu_gdt_table, cpu),
  507. GDT_ENTRY_TLS_ENTRIES * 8);
  508. load_gdt(&cpu_gdt_descr[cpu]);
  509. load_idt(&idt_descr);
  510. /*
  511. * Delete NT
  512. */
  513. __asm__("pushfl ; andl $0xffffbfff,(%esp) ; popfl");
  514. /*
  515. * Set up and load the per-CPU TSS and LDT
  516. */
  517. atomic_inc(&init_mm.mm_count);
  518. current->active_mm = &init_mm;
  519. if (current->mm)
  520. BUG();
  521. enter_lazy_tlb(&init_mm, current);
  522. load_esp0(t, thread);
  523. set_tss_desc(cpu,t);
  524. load_TR_desc();
  525. load_LDT(&init_mm.context);
  526. /* Set up doublefault TSS pointer in the GDT */
  527. __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
  528. /* Clear %fs and %gs. */
  529. asm volatile ("xorl %eax, %eax; movl %eax, %fs; movl %eax, %gs");
  530. /* Clear all 6 debug registers: */
  531. set_debugreg(0, 0);
  532. set_debugreg(0, 1);
  533. set_debugreg(0, 2);
  534. set_debugreg(0, 3);
  535. set_debugreg(0, 6);
  536. set_debugreg(0, 7);
  537. /*
  538. * Force FPU initialization:
  539. */
  540. current_thread_info()->status = 0;
  541. clear_used_math();
  542. mxcsr_feature_mask_init();
  543. }
  544. #ifdef CONFIG_HOTPLUG_CPU
  545. void __devinit cpu_uninit(void)
  546. {
  547. int cpu = raw_smp_processor_id();
  548. cpu_clear(cpu, cpu_initialized);
  549. /* lazy TLB state */
  550. per_cpu(cpu_tlbstate, cpu).state = 0;
  551. per_cpu(cpu_tlbstate, cpu).active_mm = &init_mm;
  552. }
  553. #endif