setup_64.c 31 KB

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  1. /*
  2. * Copyright (C) 1995 Linus Torvalds
  3. */
  4. /*
  5. * This file handles the architecture-dependent parts of initialization
  6. */
  7. #include <linux/errno.h>
  8. #include <linux/sched.h>
  9. #include <linux/kernel.h>
  10. #include <linux/mm.h>
  11. #include <linux/stddef.h>
  12. #include <linux/unistd.h>
  13. #include <linux/ptrace.h>
  14. #include <linux/slab.h>
  15. #include <linux/user.h>
  16. #include <linux/a.out.h>
  17. #include <linux/screen_info.h>
  18. #include <linux/ioport.h>
  19. #include <linux/delay.h>
  20. #include <linux/init.h>
  21. #include <linux/initrd.h>
  22. #include <linux/highmem.h>
  23. #include <linux/bootmem.h>
  24. #include <linux/module.h>
  25. #include <asm/processor.h>
  26. #include <linux/console.h>
  27. #include <linux/seq_file.h>
  28. #include <linux/crash_dump.h>
  29. #include <linux/root_dev.h>
  30. #include <linux/pci.h>
  31. #include <linux/acpi.h>
  32. #include <linux/kallsyms.h>
  33. #include <linux/edd.h>
  34. #include <linux/mmzone.h>
  35. #include <linux/kexec.h>
  36. #include <linux/cpufreq.h>
  37. #include <linux/dmi.h>
  38. #include <linux/dma-mapping.h>
  39. #include <linux/ctype.h>
  40. #include <asm/mtrr.h>
  41. #include <asm/uaccess.h>
  42. #include <asm/system.h>
  43. #include <asm/io.h>
  44. #include <asm/smp.h>
  45. #include <asm/msr.h>
  46. #include <asm/desc.h>
  47. #include <video/edid.h>
  48. #include <asm/e820.h>
  49. #include <asm/dma.h>
  50. #include <asm/mpspec.h>
  51. #include <asm/mmu_context.h>
  52. #include <asm/proto.h>
  53. #include <asm/setup.h>
  54. #include <asm/mach_apic.h>
  55. #include <asm/numa.h>
  56. #include <asm/sections.h>
  57. #include <asm/dmi.h>
  58. #include <asm/cacheflush.h>
  59. /*
  60. * Machine setup..
  61. */
  62. struct cpuinfo_x86 boot_cpu_data __read_mostly;
  63. EXPORT_SYMBOL(boot_cpu_data);
  64. unsigned long mmu_cr4_features;
  65. /* Boot loader ID as an integer, for the benefit of proc_dointvec */
  66. int bootloader_type;
  67. unsigned long saved_video_mode;
  68. int force_mwait __cpuinitdata;
  69. /*
  70. * Early DMI memory
  71. */
  72. int dmi_alloc_index;
  73. char dmi_alloc_data[DMI_MAX_DATA];
  74. /*
  75. * Setup options
  76. */
  77. struct screen_info screen_info;
  78. EXPORT_SYMBOL(screen_info);
  79. struct sys_desc_table_struct {
  80. unsigned short length;
  81. unsigned char table[0];
  82. };
  83. struct edid_info edid_info;
  84. EXPORT_SYMBOL_GPL(edid_info);
  85. extern int root_mountflags;
  86. char __initdata command_line[COMMAND_LINE_SIZE];
  87. struct resource standard_io_resources[] = {
  88. { .name = "dma1", .start = 0x00, .end = 0x1f,
  89. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  90. { .name = "pic1", .start = 0x20, .end = 0x21,
  91. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  92. { .name = "timer0", .start = 0x40, .end = 0x43,
  93. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  94. { .name = "timer1", .start = 0x50, .end = 0x53,
  95. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  96. { .name = "keyboard", .start = 0x60, .end = 0x6f,
  97. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  98. { .name = "dma page reg", .start = 0x80, .end = 0x8f,
  99. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  100. { .name = "pic2", .start = 0xa0, .end = 0xa1,
  101. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  102. { .name = "dma2", .start = 0xc0, .end = 0xdf,
  103. .flags = IORESOURCE_BUSY | IORESOURCE_IO },
  104. { .name = "fpu", .start = 0xf0, .end = 0xff,
  105. .flags = IORESOURCE_BUSY | IORESOURCE_IO }
  106. };
  107. #define IORESOURCE_RAM (IORESOURCE_BUSY | IORESOURCE_MEM)
  108. struct resource data_resource = {
  109. .name = "Kernel data",
  110. .start = 0,
  111. .end = 0,
  112. .flags = IORESOURCE_RAM,
  113. };
  114. struct resource code_resource = {
  115. .name = "Kernel code",
  116. .start = 0,
  117. .end = 0,
  118. .flags = IORESOURCE_RAM,
  119. };
  120. struct resource bss_resource = {
  121. .name = "Kernel bss",
  122. .start = 0,
  123. .end = 0,
  124. .flags = IORESOURCE_RAM,
  125. };
  126. #ifdef CONFIG_PROC_VMCORE
  127. /* elfcorehdr= specifies the location of elf core header
  128. * stored by the crashed kernel. This option will be passed
  129. * by kexec loader to the capture kernel.
  130. */
  131. static int __init setup_elfcorehdr(char *arg)
  132. {
  133. char *end;
  134. if (!arg)
  135. return -EINVAL;
  136. elfcorehdr_addr = memparse(arg, &end);
  137. return end > arg ? 0 : -EINVAL;
  138. }
  139. early_param("elfcorehdr", setup_elfcorehdr);
  140. #endif
  141. #ifndef CONFIG_NUMA
  142. static void __init
  143. contig_initmem_init(unsigned long start_pfn, unsigned long end_pfn)
  144. {
  145. unsigned long bootmap_size, bootmap;
  146. bootmap_size = bootmem_bootmap_pages(end_pfn)<<PAGE_SHIFT;
  147. bootmap = find_e820_area(0, end_pfn<<PAGE_SHIFT, bootmap_size);
  148. if (bootmap == -1L)
  149. panic("Cannot find bootmem map of size %ld\n",bootmap_size);
  150. bootmap_size = init_bootmem(bootmap >> PAGE_SHIFT, end_pfn);
  151. e820_register_active_regions(0, start_pfn, end_pfn);
  152. free_bootmem_with_active_regions(0, end_pfn);
  153. reserve_bootmem(bootmap, bootmap_size);
  154. }
  155. #endif
  156. #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
  157. struct edd edd;
  158. #ifdef CONFIG_EDD_MODULE
  159. EXPORT_SYMBOL(edd);
  160. #endif
  161. /**
  162. * copy_edd() - Copy the BIOS EDD information
  163. * from boot_params into a safe place.
  164. *
  165. */
  166. static inline void copy_edd(void)
  167. {
  168. memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
  169. sizeof(edd.mbr_signature));
  170. memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
  171. edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
  172. edd.edd_info_nr = boot_params.eddbuf_entries;
  173. }
  174. #else
  175. static inline void copy_edd(void)
  176. {
  177. }
  178. #endif
  179. #ifdef CONFIG_KEXEC
  180. static void __init reserve_crashkernel(void)
  181. {
  182. unsigned long long free_mem;
  183. unsigned long long crash_size, crash_base;
  184. int ret;
  185. free_mem = ((unsigned long long)max_low_pfn - min_low_pfn) << PAGE_SHIFT;
  186. ret = parse_crashkernel(boot_command_line, free_mem,
  187. &crash_size, &crash_base);
  188. if (ret == 0 && crash_size) {
  189. if (crash_base > 0) {
  190. printk(KERN_INFO "Reserving %ldMB of memory at %ldMB "
  191. "for crashkernel (System RAM: %ldMB)\n",
  192. (unsigned long)(crash_size >> 20),
  193. (unsigned long)(crash_base >> 20),
  194. (unsigned long)(free_mem >> 20));
  195. crashk_res.start = crash_base;
  196. crashk_res.end = crash_base + crash_size - 1;
  197. reserve_bootmem(crash_base, crash_size);
  198. } else
  199. printk(KERN_INFO "crashkernel reservation failed - "
  200. "you have to specify a base address\n");
  201. }
  202. }
  203. #else
  204. static inline void __init reserve_crashkernel(void)
  205. {}
  206. #endif
  207. #define EBDA_ADDR_POINTER 0x40E
  208. unsigned __initdata ebda_addr;
  209. unsigned __initdata ebda_size;
  210. static void discover_ebda(void)
  211. {
  212. /*
  213. * there is a real-mode segmented pointer pointing to the
  214. * 4K EBDA area at 0x40E
  215. */
  216. ebda_addr = *(unsigned short *)__va(EBDA_ADDR_POINTER);
  217. ebda_addr <<= 4;
  218. ebda_size = *(unsigned short *)__va(ebda_addr);
  219. /* Round EBDA up to pages */
  220. if (ebda_size == 0)
  221. ebda_size = 1;
  222. ebda_size <<= 10;
  223. ebda_size = round_up(ebda_size + (ebda_addr & ~PAGE_MASK), PAGE_SIZE);
  224. if (ebda_size > 64*1024)
  225. ebda_size = 64*1024;
  226. }
  227. void __init setup_arch(char **cmdline_p)
  228. {
  229. printk(KERN_INFO "Command line: %s\n", boot_command_line);
  230. ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
  231. screen_info = boot_params.screen_info;
  232. edid_info = boot_params.edid_info;
  233. saved_video_mode = boot_params.hdr.vid_mode;
  234. bootloader_type = boot_params.hdr.type_of_loader;
  235. #ifdef CONFIG_BLK_DEV_RAM
  236. rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
  237. rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
  238. rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
  239. #endif
  240. setup_memory_region();
  241. copy_edd();
  242. if (!boot_params.hdr.root_flags)
  243. root_mountflags &= ~MS_RDONLY;
  244. init_mm.start_code = (unsigned long) &_text;
  245. init_mm.end_code = (unsigned long) &_etext;
  246. init_mm.end_data = (unsigned long) &_edata;
  247. init_mm.brk = (unsigned long) &_end;
  248. code_resource.start = virt_to_phys(&_text);
  249. code_resource.end = virt_to_phys(&_etext)-1;
  250. data_resource.start = virt_to_phys(&_etext);
  251. data_resource.end = virt_to_phys(&_edata)-1;
  252. bss_resource.start = virt_to_phys(&__bss_start);
  253. bss_resource.end = virt_to_phys(&__bss_stop)-1;
  254. early_identify_cpu(&boot_cpu_data);
  255. strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
  256. *cmdline_p = command_line;
  257. parse_early_param();
  258. finish_e820_parsing();
  259. e820_register_active_regions(0, 0, -1UL);
  260. /*
  261. * partially used pages are not usable - thus
  262. * we are rounding upwards:
  263. */
  264. end_pfn = e820_end_of_ram();
  265. num_physpages = end_pfn;
  266. check_efer();
  267. discover_ebda();
  268. init_memory_mapping(0, (end_pfn_map << PAGE_SHIFT));
  269. dmi_scan_machine();
  270. #ifdef CONFIG_SMP
  271. /* setup to use the static apicid table during kernel startup */
  272. x86_cpu_to_apicid_ptr = (void *)&x86_cpu_to_apicid_init;
  273. #endif
  274. #ifdef CONFIG_ACPI
  275. /*
  276. * Initialize the ACPI boot-time table parser (gets the RSDP and SDT).
  277. * Call this early for SRAT node setup.
  278. */
  279. acpi_boot_table_init();
  280. #endif
  281. /* How many end-of-memory variables you have, grandma! */
  282. max_low_pfn = end_pfn;
  283. max_pfn = end_pfn;
  284. high_memory = (void *)__va(end_pfn * PAGE_SIZE - 1) + 1;
  285. /* Remove active ranges so rediscovery with NUMA-awareness happens */
  286. remove_all_active_ranges();
  287. #ifdef CONFIG_ACPI_NUMA
  288. /*
  289. * Parse SRAT to discover nodes.
  290. */
  291. acpi_numa_init();
  292. #endif
  293. #ifdef CONFIG_NUMA
  294. numa_initmem_init(0, end_pfn);
  295. #else
  296. contig_initmem_init(0, end_pfn);
  297. #endif
  298. /* Reserve direct mapping */
  299. reserve_bootmem_generic(table_start << PAGE_SHIFT,
  300. (table_end - table_start) << PAGE_SHIFT);
  301. /* reserve kernel */
  302. reserve_bootmem_generic(__pa_symbol(&_text),
  303. __pa_symbol(&_end) - __pa_symbol(&_text));
  304. /*
  305. * reserve physical page 0 - it's a special BIOS page on many boxes,
  306. * enabling clean reboots, SMP operation, laptop functions.
  307. */
  308. reserve_bootmem_generic(0, PAGE_SIZE);
  309. /* reserve ebda region */
  310. if (ebda_addr)
  311. reserve_bootmem_generic(ebda_addr, ebda_size);
  312. #ifdef CONFIG_NUMA
  313. /* reserve nodemap region */
  314. if (nodemap_addr)
  315. reserve_bootmem_generic(nodemap_addr, nodemap_size);
  316. #endif
  317. #ifdef CONFIG_SMP
  318. /* Reserve SMP trampoline */
  319. reserve_bootmem_generic(SMP_TRAMPOLINE_BASE, 2*PAGE_SIZE);
  320. #endif
  321. #ifdef CONFIG_ACPI_SLEEP
  322. /*
  323. * Reserve low memory region for sleep support.
  324. */
  325. acpi_reserve_bootmem();
  326. #endif
  327. /*
  328. * Find and reserve possible boot-time SMP configuration:
  329. */
  330. find_smp_config();
  331. #ifdef CONFIG_BLK_DEV_INITRD
  332. if (boot_params.hdr.type_of_loader && boot_params.hdr.ramdisk_image) {
  333. unsigned long ramdisk_image = boot_params.hdr.ramdisk_image;
  334. unsigned long ramdisk_size = boot_params.hdr.ramdisk_size;
  335. unsigned long ramdisk_end = ramdisk_image + ramdisk_size;
  336. unsigned long end_of_mem = end_pfn << PAGE_SHIFT;
  337. if (ramdisk_end <= end_of_mem) {
  338. reserve_bootmem_generic(ramdisk_image, ramdisk_size);
  339. initrd_start = ramdisk_image + PAGE_OFFSET;
  340. initrd_end = initrd_start+ramdisk_size;
  341. } else {
  342. printk(KERN_ERR "initrd extends beyond end of memory "
  343. "(0x%08lx > 0x%08lx)\ndisabling initrd\n",
  344. ramdisk_end, end_of_mem);
  345. initrd_start = 0;
  346. }
  347. }
  348. #endif
  349. reserve_crashkernel();
  350. paging_init();
  351. #ifdef CONFIG_PCI
  352. early_quirks();
  353. #endif
  354. /*
  355. * set this early, so we dont allocate cpu0
  356. * if MADT list doesnt list BSP first
  357. * mpparse.c/MP_processor_info() allocates logical cpu numbers.
  358. */
  359. cpu_set(0, cpu_present_map);
  360. #ifdef CONFIG_ACPI
  361. /*
  362. * Read APIC and some other early information from ACPI tables.
  363. */
  364. acpi_boot_init();
  365. #endif
  366. init_cpu_to_node();
  367. /*
  368. * get boot-time SMP configuration:
  369. */
  370. if (smp_found_config)
  371. get_smp_config();
  372. init_apic_mappings();
  373. /*
  374. * We trust e820 completely. No explicit ROM probing in memory.
  375. */
  376. e820_reserve_resources();
  377. e820_mark_nosave_regions();
  378. {
  379. unsigned i;
  380. /* request I/O space for devices used on all i[345]86 PCs */
  381. for (i = 0; i < ARRAY_SIZE(standard_io_resources); i++)
  382. request_resource(&ioport_resource, &standard_io_resources[i]);
  383. }
  384. e820_setup_gap();
  385. #ifdef CONFIG_VT
  386. #if defined(CONFIG_VGA_CONSOLE)
  387. conswitchp = &vga_con;
  388. #elif defined(CONFIG_DUMMY_CONSOLE)
  389. conswitchp = &dummy_con;
  390. #endif
  391. #endif
  392. }
  393. static int __cpuinit get_model_name(struct cpuinfo_x86 *c)
  394. {
  395. unsigned int *v;
  396. if (c->extended_cpuid_level < 0x80000004)
  397. return 0;
  398. v = (unsigned int *) c->x86_model_id;
  399. cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
  400. cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
  401. cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
  402. c->x86_model_id[48] = 0;
  403. return 1;
  404. }
  405. static void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
  406. {
  407. unsigned int n, dummy, eax, ebx, ecx, edx;
  408. n = c->extended_cpuid_level;
  409. if (n >= 0x80000005) {
  410. cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
  411. printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
  412. edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
  413. c->x86_cache_size=(ecx>>24)+(edx>>24);
  414. /* On K8 L1 TLB is inclusive, so don't count it */
  415. c->x86_tlbsize = 0;
  416. }
  417. if (n >= 0x80000006) {
  418. cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
  419. ecx = cpuid_ecx(0x80000006);
  420. c->x86_cache_size = ecx >> 16;
  421. c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
  422. printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
  423. c->x86_cache_size, ecx & 0xFF);
  424. }
  425. if (n >= 0x80000007)
  426. cpuid(0x80000007, &dummy, &dummy, &dummy, &c->x86_power);
  427. if (n >= 0x80000008) {
  428. cpuid(0x80000008, &eax, &dummy, &dummy, &dummy);
  429. c->x86_virt_bits = (eax >> 8) & 0xff;
  430. c->x86_phys_bits = eax & 0xff;
  431. }
  432. }
  433. #ifdef CONFIG_NUMA
  434. static int nearby_node(int apicid)
  435. {
  436. int i;
  437. for (i = apicid - 1; i >= 0; i--) {
  438. int node = apicid_to_node[i];
  439. if (node != NUMA_NO_NODE && node_online(node))
  440. return node;
  441. }
  442. for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) {
  443. int node = apicid_to_node[i];
  444. if (node != NUMA_NO_NODE && node_online(node))
  445. return node;
  446. }
  447. return first_node(node_online_map); /* Shouldn't happen */
  448. }
  449. #endif
  450. /*
  451. * On a AMD dual core setup the lower bits of the APIC id distingush the cores.
  452. * Assumes number of cores is a power of two.
  453. */
  454. static void __init amd_detect_cmp(struct cpuinfo_x86 *c)
  455. {
  456. #ifdef CONFIG_SMP
  457. unsigned bits;
  458. #ifdef CONFIG_NUMA
  459. int cpu = smp_processor_id();
  460. int node = 0;
  461. unsigned apicid = hard_smp_processor_id();
  462. #endif
  463. unsigned ecx = cpuid_ecx(0x80000008);
  464. c->x86_max_cores = (ecx & 0xff) + 1;
  465. /* CPU telling us the core id bits shift? */
  466. bits = (ecx >> 12) & 0xF;
  467. /* Otherwise recompute */
  468. if (bits == 0) {
  469. while ((1 << bits) < c->x86_max_cores)
  470. bits++;
  471. }
  472. /* Low order bits define the core id (index of core in socket) */
  473. c->cpu_core_id = c->phys_proc_id & ((1 << bits)-1);
  474. /* Convert the APIC ID into the socket ID */
  475. c->phys_proc_id = phys_pkg_id(bits);
  476. #ifdef CONFIG_NUMA
  477. node = c->phys_proc_id;
  478. if (apicid_to_node[apicid] != NUMA_NO_NODE)
  479. node = apicid_to_node[apicid];
  480. if (!node_online(node)) {
  481. /* Two possibilities here:
  482. - The CPU is missing memory and no node was created.
  483. In that case try picking one from a nearby CPU
  484. - The APIC IDs differ from the HyperTransport node IDs
  485. which the K8 northbridge parsing fills in.
  486. Assume they are all increased by a constant offset,
  487. but in the same order as the HT nodeids.
  488. If that doesn't result in a usable node fall back to the
  489. path for the previous case. */
  490. int ht_nodeid = apicid - (cpu_data(0).phys_proc_id << bits);
  491. if (ht_nodeid >= 0 &&
  492. apicid_to_node[ht_nodeid] != NUMA_NO_NODE)
  493. node = apicid_to_node[ht_nodeid];
  494. /* Pick a nearby node */
  495. if (!node_online(node))
  496. node = nearby_node(apicid);
  497. }
  498. numa_set_node(cpu, node);
  499. printk(KERN_INFO "CPU %d/%x -> Node %d\n", cpu, apicid, node);
  500. #endif
  501. #endif
  502. }
  503. #define ENABLE_C1E_MASK 0x18000000
  504. #define CPUID_PROCESSOR_SIGNATURE 1
  505. #define CPUID_XFAM 0x0ff00000
  506. #define CPUID_XFAM_K8 0x00000000
  507. #define CPUID_XFAM_10H 0x00100000
  508. #define CPUID_XFAM_11H 0x00200000
  509. #define CPUID_XMOD 0x000f0000
  510. #define CPUID_XMOD_REV_F 0x00040000
  511. /* AMD systems with C1E don't have a working lAPIC timer. Check for that. */
  512. static __cpuinit int amd_apic_timer_broken(void)
  513. {
  514. u32 lo, hi;
  515. u32 eax = cpuid_eax(CPUID_PROCESSOR_SIGNATURE);
  516. switch (eax & CPUID_XFAM) {
  517. case CPUID_XFAM_K8:
  518. if ((eax & CPUID_XMOD) < CPUID_XMOD_REV_F)
  519. break;
  520. case CPUID_XFAM_10H:
  521. case CPUID_XFAM_11H:
  522. rdmsr(MSR_K8_ENABLE_C1E, lo, hi);
  523. if (lo & ENABLE_C1E_MASK)
  524. return 1;
  525. break;
  526. default:
  527. /* err on the side of caution */
  528. return 1;
  529. }
  530. return 0;
  531. }
  532. static void __cpuinit init_amd(struct cpuinfo_x86 *c)
  533. {
  534. unsigned level;
  535. #ifdef CONFIG_SMP
  536. unsigned long value;
  537. /*
  538. * Disable TLB flush filter by setting HWCR.FFDIS on K8
  539. * bit 6 of msr C001_0015
  540. *
  541. * Errata 63 for SH-B3 steppings
  542. * Errata 122 for all steppings (F+ have it disabled by default)
  543. */
  544. if (c->x86 == 15) {
  545. rdmsrl(MSR_K8_HWCR, value);
  546. value |= 1 << 6;
  547. wrmsrl(MSR_K8_HWCR, value);
  548. }
  549. #endif
  550. /* Bit 31 in normal CPUID used for nonstandard 3DNow ID;
  551. 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */
  552. clear_bit(0*32+31, &c->x86_capability);
  553. /* On C+ stepping K8 rep microcode works well for copy/memset */
  554. level = cpuid_eax(1);
  555. if (c->x86 == 15 && ((level >= 0x0f48 && level < 0x0f50) || level >= 0x0f58))
  556. set_bit(X86_FEATURE_REP_GOOD, &c->x86_capability);
  557. if (c->x86 == 0x10 || c->x86 == 0x11)
  558. set_bit(X86_FEATURE_REP_GOOD, &c->x86_capability);
  559. /* Enable workaround for FXSAVE leak */
  560. if (c->x86 >= 6)
  561. set_bit(X86_FEATURE_FXSAVE_LEAK, &c->x86_capability);
  562. level = get_model_name(c);
  563. if (!level) {
  564. switch (c->x86) {
  565. case 15:
  566. /* Should distinguish Models here, but this is only
  567. a fallback anyways. */
  568. strcpy(c->x86_model_id, "Hammer");
  569. break;
  570. }
  571. }
  572. display_cacheinfo(c);
  573. /* c->x86_power is 8000_0007 edx. Bit 8 is constant TSC */
  574. if (c->x86_power & (1<<8))
  575. set_bit(X86_FEATURE_CONSTANT_TSC, &c->x86_capability);
  576. /* Multi core CPU? */
  577. if (c->extended_cpuid_level >= 0x80000008)
  578. amd_detect_cmp(c);
  579. if (c->extended_cpuid_level >= 0x80000006 &&
  580. (cpuid_edx(0x80000006) & 0xf000))
  581. num_cache_leaves = 4;
  582. else
  583. num_cache_leaves = 3;
  584. if (c->x86 == 0xf || c->x86 == 0x10 || c->x86 == 0x11)
  585. set_bit(X86_FEATURE_K8, &c->x86_capability);
  586. /* RDTSC can be speculated around */
  587. clear_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability);
  588. /* Family 10 doesn't support C states in MWAIT so don't use it */
  589. if (c->x86 == 0x10 && !force_mwait)
  590. clear_bit(X86_FEATURE_MWAIT, &c->x86_capability);
  591. if (amd_apic_timer_broken())
  592. disable_apic_timer = 1;
  593. }
  594. static void __cpuinit detect_ht(struct cpuinfo_x86 *c)
  595. {
  596. #ifdef CONFIG_SMP
  597. u32 eax, ebx, ecx, edx;
  598. int index_msb, core_bits;
  599. cpuid(1, &eax, &ebx, &ecx, &edx);
  600. if (!cpu_has(c, X86_FEATURE_HT))
  601. return;
  602. if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
  603. goto out;
  604. smp_num_siblings = (ebx & 0xff0000) >> 16;
  605. if (smp_num_siblings == 1) {
  606. printk(KERN_INFO "CPU: Hyper-Threading is disabled\n");
  607. } else if (smp_num_siblings > 1 ) {
  608. if (smp_num_siblings > NR_CPUS) {
  609. printk(KERN_WARNING "CPU: Unsupported number of the siblings %d", smp_num_siblings);
  610. smp_num_siblings = 1;
  611. return;
  612. }
  613. index_msb = get_count_order(smp_num_siblings);
  614. c->phys_proc_id = phys_pkg_id(index_msb);
  615. smp_num_siblings = smp_num_siblings / c->x86_max_cores;
  616. index_msb = get_count_order(smp_num_siblings) ;
  617. core_bits = get_count_order(c->x86_max_cores);
  618. c->cpu_core_id = phys_pkg_id(index_msb) &
  619. ((1 << core_bits) - 1);
  620. }
  621. out:
  622. if ((c->x86_max_cores * smp_num_siblings) > 1) {
  623. printk(KERN_INFO "CPU: Physical Processor ID: %d\n", c->phys_proc_id);
  624. printk(KERN_INFO "CPU: Processor Core ID: %d\n", c->cpu_core_id);
  625. }
  626. #endif
  627. }
  628. /*
  629. * find out the number of processor cores on the die
  630. */
  631. static int __cpuinit intel_num_cpu_cores(struct cpuinfo_x86 *c)
  632. {
  633. unsigned int eax, t;
  634. if (c->cpuid_level < 4)
  635. return 1;
  636. cpuid_count(4, 0, &eax, &t, &t, &t);
  637. if (eax & 0x1f)
  638. return ((eax >> 26) + 1);
  639. else
  640. return 1;
  641. }
  642. static void srat_detect_node(void)
  643. {
  644. #ifdef CONFIG_NUMA
  645. unsigned node;
  646. int cpu = smp_processor_id();
  647. int apicid = hard_smp_processor_id();
  648. /* Don't do the funky fallback heuristics the AMD version employs
  649. for now. */
  650. node = apicid_to_node[apicid];
  651. if (node == NUMA_NO_NODE)
  652. node = first_node(node_online_map);
  653. numa_set_node(cpu, node);
  654. printk(KERN_INFO "CPU %d/%x -> Node %d\n", cpu, apicid, node);
  655. #endif
  656. }
  657. static void __cpuinit init_intel(struct cpuinfo_x86 *c)
  658. {
  659. /* Cache sizes */
  660. unsigned n;
  661. init_intel_cacheinfo(c);
  662. if (c->cpuid_level > 9 ) {
  663. unsigned eax = cpuid_eax(10);
  664. /* Check for version and the number of counters */
  665. if ((eax & 0xff) && (((eax>>8) & 0xff) > 1))
  666. set_bit(X86_FEATURE_ARCH_PERFMON, &c->x86_capability);
  667. }
  668. if (cpu_has_ds) {
  669. unsigned int l1, l2;
  670. rdmsr(MSR_IA32_MISC_ENABLE, l1, l2);
  671. if (!(l1 & (1<<11)))
  672. set_bit(X86_FEATURE_BTS, c->x86_capability);
  673. if (!(l1 & (1<<12)))
  674. set_bit(X86_FEATURE_PEBS, c->x86_capability);
  675. }
  676. n = c->extended_cpuid_level;
  677. if (n >= 0x80000008) {
  678. unsigned eax = cpuid_eax(0x80000008);
  679. c->x86_virt_bits = (eax >> 8) & 0xff;
  680. c->x86_phys_bits = eax & 0xff;
  681. /* CPUID workaround for Intel 0F34 CPU */
  682. if (c->x86_vendor == X86_VENDOR_INTEL &&
  683. c->x86 == 0xF && c->x86_model == 0x3 &&
  684. c->x86_mask == 0x4)
  685. c->x86_phys_bits = 36;
  686. }
  687. if (c->x86 == 15)
  688. c->x86_cache_alignment = c->x86_clflush_size * 2;
  689. if ((c->x86 == 0xf && c->x86_model >= 0x03) ||
  690. (c->x86 == 0x6 && c->x86_model >= 0x0e))
  691. set_bit(X86_FEATURE_CONSTANT_TSC, &c->x86_capability);
  692. if (c->x86 == 6)
  693. set_bit(X86_FEATURE_REP_GOOD, &c->x86_capability);
  694. if (c->x86 == 15)
  695. set_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability);
  696. else
  697. clear_bit(X86_FEATURE_SYNC_RDTSC, &c->x86_capability);
  698. c->x86_max_cores = intel_num_cpu_cores(c);
  699. srat_detect_node();
  700. }
  701. static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
  702. {
  703. char *v = c->x86_vendor_id;
  704. if (!strcmp(v, "AuthenticAMD"))
  705. c->x86_vendor = X86_VENDOR_AMD;
  706. else if (!strcmp(v, "GenuineIntel"))
  707. c->x86_vendor = X86_VENDOR_INTEL;
  708. else
  709. c->x86_vendor = X86_VENDOR_UNKNOWN;
  710. }
  711. struct cpu_model_info {
  712. int vendor;
  713. int family;
  714. char *model_names[16];
  715. };
  716. /* Do some early cpuid on the boot CPU to get some parameter that are
  717. needed before check_bugs. Everything advanced is in identify_cpu
  718. below. */
  719. void __cpuinit early_identify_cpu(struct cpuinfo_x86 *c)
  720. {
  721. u32 tfms;
  722. c->loops_per_jiffy = loops_per_jiffy;
  723. c->x86_cache_size = -1;
  724. c->x86_vendor = X86_VENDOR_UNKNOWN;
  725. c->x86_model = c->x86_mask = 0; /* So far unknown... */
  726. c->x86_vendor_id[0] = '\0'; /* Unset */
  727. c->x86_model_id[0] = '\0'; /* Unset */
  728. c->x86_clflush_size = 64;
  729. c->x86_cache_alignment = c->x86_clflush_size;
  730. c->x86_max_cores = 1;
  731. c->extended_cpuid_level = 0;
  732. memset(&c->x86_capability, 0, sizeof c->x86_capability);
  733. /* Get vendor name */
  734. cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
  735. (unsigned int *)&c->x86_vendor_id[0],
  736. (unsigned int *)&c->x86_vendor_id[8],
  737. (unsigned int *)&c->x86_vendor_id[4]);
  738. get_cpu_vendor(c);
  739. /* Initialize the standard set of capabilities */
  740. /* Note that the vendor-specific code below might override */
  741. /* Intel-defined flags: level 0x00000001 */
  742. if (c->cpuid_level >= 0x00000001) {
  743. __u32 misc;
  744. cpuid(0x00000001, &tfms, &misc, &c->x86_capability[4],
  745. &c->x86_capability[0]);
  746. c->x86 = (tfms >> 8) & 0xf;
  747. c->x86_model = (tfms >> 4) & 0xf;
  748. c->x86_mask = tfms & 0xf;
  749. if (c->x86 == 0xf)
  750. c->x86 += (tfms >> 20) & 0xff;
  751. if (c->x86 >= 0x6)
  752. c->x86_model += ((tfms >> 16) & 0xF) << 4;
  753. if (c->x86_capability[0] & (1<<19))
  754. c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
  755. } else {
  756. /* Have CPUID level 0 only - unheard of */
  757. c->x86 = 4;
  758. }
  759. #ifdef CONFIG_SMP
  760. c->phys_proc_id = (cpuid_ebx(1) >> 24) & 0xff;
  761. #endif
  762. }
  763. /*
  764. * This does the hard work of actually picking apart the CPU stuff...
  765. */
  766. void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
  767. {
  768. int i;
  769. u32 xlvl;
  770. early_identify_cpu(c);
  771. /* AMD-defined flags: level 0x80000001 */
  772. xlvl = cpuid_eax(0x80000000);
  773. c->extended_cpuid_level = xlvl;
  774. if ((xlvl & 0xffff0000) == 0x80000000) {
  775. if (xlvl >= 0x80000001) {
  776. c->x86_capability[1] = cpuid_edx(0x80000001);
  777. c->x86_capability[6] = cpuid_ecx(0x80000001);
  778. }
  779. if (xlvl >= 0x80000004)
  780. get_model_name(c); /* Default name */
  781. }
  782. /* Transmeta-defined flags: level 0x80860001 */
  783. xlvl = cpuid_eax(0x80860000);
  784. if ((xlvl & 0xffff0000) == 0x80860000) {
  785. /* Don't set x86_cpuid_level here for now to not confuse. */
  786. if (xlvl >= 0x80860001)
  787. c->x86_capability[2] = cpuid_edx(0x80860001);
  788. }
  789. init_scattered_cpuid_features(c);
  790. c->apicid = phys_pkg_id(0);
  791. /*
  792. * Vendor-specific initialization. In this section we
  793. * canonicalize the feature flags, meaning if there are
  794. * features a certain CPU supports which CPUID doesn't
  795. * tell us, CPUID claiming incorrect flags, or other bugs,
  796. * we handle them here.
  797. *
  798. * At the end of this section, c->x86_capability better
  799. * indicate the features this CPU genuinely supports!
  800. */
  801. switch (c->x86_vendor) {
  802. case X86_VENDOR_AMD:
  803. init_amd(c);
  804. break;
  805. case X86_VENDOR_INTEL:
  806. init_intel(c);
  807. break;
  808. case X86_VENDOR_UNKNOWN:
  809. default:
  810. display_cacheinfo(c);
  811. break;
  812. }
  813. select_idle_routine(c);
  814. detect_ht(c);
  815. /*
  816. * On SMP, boot_cpu_data holds the common feature set between
  817. * all CPUs; so make sure that we indicate which features are
  818. * common between the CPUs. The first time this routine gets
  819. * executed, c == &boot_cpu_data.
  820. */
  821. if (c != &boot_cpu_data) {
  822. /* AND the already accumulated flags with these */
  823. for (i = 0 ; i < NCAPINTS ; i++)
  824. boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
  825. }
  826. #ifdef CONFIG_X86_MCE
  827. mcheck_init(c);
  828. #endif
  829. if (c != &boot_cpu_data)
  830. mtrr_ap_init();
  831. #ifdef CONFIG_NUMA
  832. numa_add_cpu(smp_processor_id());
  833. #endif
  834. }
  835. void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
  836. {
  837. if (c->x86_model_id[0])
  838. printk("%s", c->x86_model_id);
  839. if (c->x86_mask || c->cpuid_level >= 0)
  840. printk(" stepping %02x\n", c->x86_mask);
  841. else
  842. printk("\n");
  843. }
  844. /*
  845. * Get CPU information for use by the procfs.
  846. */
  847. static int show_cpuinfo(struct seq_file *m, void *v)
  848. {
  849. struct cpuinfo_x86 *c = v;
  850. int cpu = 0;
  851. /*
  852. * These flag bits must match the definitions in <asm/cpufeature.h>.
  853. * NULL means this bit is undefined or reserved; either way it doesn't
  854. * have meaning as far as Linux is concerned. Note that it's important
  855. * to realize there is a difference between this table and CPUID -- if
  856. * applications want to get the raw CPUID data, they should access
  857. * /dev/cpu/<cpu_nr>/cpuid instead.
  858. */
  859. static const char *const x86_cap_flags[] = {
  860. /* Intel-defined */
  861. "fpu", "vme", "de", "pse", "tsc", "msr", "pae", "mce",
  862. "cx8", "apic", NULL, "sep", "mtrr", "pge", "mca", "cmov",
  863. "pat", "pse36", "pn", "clflush", NULL, "dts", "acpi", "mmx",
  864. "fxsr", "sse", "sse2", "ss", "ht", "tm", "ia64", "pbe",
  865. /* AMD-defined */
  866. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  867. NULL, NULL, NULL, "syscall", NULL, NULL, NULL, NULL,
  868. NULL, NULL, NULL, NULL, "nx", NULL, "mmxext", NULL,
  869. NULL, "fxsr_opt", "pdpe1gb", "rdtscp", NULL, "lm",
  870. "3dnowext", "3dnow",
  871. /* Transmeta-defined */
  872. "recovery", "longrun", NULL, "lrti", NULL, NULL, NULL, NULL,
  873. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  874. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  875. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  876. /* Other (Linux-defined) */
  877. "cxmmx", "k6_mtrr", "cyrix_arr", "centaur_mcr",
  878. NULL, NULL, NULL, NULL,
  879. "constant_tsc", "up", NULL, "arch_perfmon",
  880. "pebs", "bts", NULL, "sync_rdtsc",
  881. "rep_good", NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  882. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  883. /* Intel-defined (#2) */
  884. "pni", NULL, NULL, "monitor", "ds_cpl", "vmx", "smx", "est",
  885. "tm2", "ssse3", "cid", NULL, NULL, "cx16", "xtpr", NULL,
  886. NULL, NULL, "dca", "sse4_1", "sse4_2", NULL, NULL, "popcnt",
  887. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  888. /* VIA/Cyrix/Centaur-defined */
  889. NULL, NULL, "rng", "rng_en", NULL, NULL, "ace", "ace_en",
  890. "ace2", "ace2_en", "phe", "phe_en", "pmm", "pmm_en", NULL, NULL,
  891. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  892. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  893. /* AMD-defined (#2) */
  894. "lahf_lm", "cmp_legacy", "svm", "extapic",
  895. "cr8_legacy", "abm", "sse4a", "misalignsse",
  896. "3dnowprefetch", "osvw", "ibs", "sse5",
  897. "skinit", "wdt", NULL, NULL,
  898. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  899. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  900. /* Auxiliary (Linux-defined) */
  901. "ida", NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  902. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  903. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  904. NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
  905. };
  906. static const char *const x86_power_flags[] = {
  907. "ts", /* temperature sensor */
  908. "fid", /* frequency id control */
  909. "vid", /* voltage id control */
  910. "ttp", /* thermal trip */
  911. "tm",
  912. "stc",
  913. "100mhzsteps",
  914. "hwpstate",
  915. "", /* tsc invariant mapped to constant_tsc */
  916. /* nothing */
  917. };
  918. #ifdef CONFIG_SMP
  919. cpu = c->cpu_index;
  920. #endif
  921. seq_printf(m,"processor\t: %u\n"
  922. "vendor_id\t: %s\n"
  923. "cpu family\t: %d\n"
  924. "model\t\t: %d\n"
  925. "model name\t: %s\n",
  926. (unsigned)cpu,
  927. c->x86_vendor_id[0] ? c->x86_vendor_id : "unknown",
  928. c->x86,
  929. (int)c->x86_model,
  930. c->x86_model_id[0] ? c->x86_model_id : "unknown");
  931. if (c->x86_mask || c->cpuid_level >= 0)
  932. seq_printf(m, "stepping\t: %d\n", c->x86_mask);
  933. else
  934. seq_printf(m, "stepping\t: unknown\n");
  935. if (cpu_has(c,X86_FEATURE_TSC)) {
  936. unsigned int freq = cpufreq_quick_get((unsigned)cpu);
  937. if (!freq)
  938. freq = cpu_khz;
  939. seq_printf(m, "cpu MHz\t\t: %u.%03u\n",
  940. freq / 1000, (freq % 1000));
  941. }
  942. /* Cache size */
  943. if (c->x86_cache_size >= 0)
  944. seq_printf(m, "cache size\t: %d KB\n", c->x86_cache_size);
  945. #ifdef CONFIG_SMP
  946. if (smp_num_siblings * c->x86_max_cores > 1) {
  947. seq_printf(m, "physical id\t: %d\n", c->phys_proc_id);
  948. seq_printf(m, "siblings\t: %d\n",
  949. cpus_weight(per_cpu(cpu_core_map, cpu)));
  950. seq_printf(m, "core id\t\t: %d\n", c->cpu_core_id);
  951. seq_printf(m, "cpu cores\t: %d\n", c->booted_cores);
  952. }
  953. #endif
  954. seq_printf(m,
  955. "fpu\t\t: yes\n"
  956. "fpu_exception\t: yes\n"
  957. "cpuid level\t: %d\n"
  958. "wp\t\t: yes\n"
  959. "flags\t\t:",
  960. c->cpuid_level);
  961. {
  962. int i;
  963. for ( i = 0 ; i < 32*NCAPINTS ; i++ )
  964. if (cpu_has(c, i) && x86_cap_flags[i] != NULL)
  965. seq_printf(m, " %s", x86_cap_flags[i]);
  966. }
  967. seq_printf(m, "\nbogomips\t: %lu.%02lu\n",
  968. c->loops_per_jiffy/(500000/HZ),
  969. (c->loops_per_jiffy/(5000/HZ)) % 100);
  970. if (c->x86_tlbsize > 0)
  971. seq_printf(m, "TLB size\t: %d 4K pages\n", c->x86_tlbsize);
  972. seq_printf(m, "clflush size\t: %d\n", c->x86_clflush_size);
  973. seq_printf(m, "cache_alignment\t: %d\n", c->x86_cache_alignment);
  974. seq_printf(m, "address sizes\t: %u bits physical, %u bits virtual\n",
  975. c->x86_phys_bits, c->x86_virt_bits);
  976. seq_printf(m, "power management:");
  977. {
  978. unsigned i;
  979. for (i = 0; i < 32; i++)
  980. if (c->x86_power & (1 << i)) {
  981. if (i < ARRAY_SIZE(x86_power_flags) &&
  982. x86_power_flags[i])
  983. seq_printf(m, "%s%s",
  984. x86_power_flags[i][0]?" ":"",
  985. x86_power_flags[i]);
  986. else
  987. seq_printf(m, " [%d]", i);
  988. }
  989. }
  990. seq_printf(m, "\n\n");
  991. return 0;
  992. }
  993. static void *c_start(struct seq_file *m, loff_t *pos)
  994. {
  995. if (*pos == 0) /* just in case, cpu 0 is not the first */
  996. *pos = first_cpu(cpu_online_map);
  997. if ((*pos) < NR_CPUS && cpu_online(*pos))
  998. return &cpu_data(*pos);
  999. return NULL;
  1000. }
  1001. static void *c_next(struct seq_file *m, void *v, loff_t *pos)
  1002. {
  1003. *pos = next_cpu(*pos, cpu_online_map);
  1004. return c_start(m, pos);
  1005. }
  1006. static void c_stop(struct seq_file *m, void *v)
  1007. {
  1008. }
  1009. struct seq_operations cpuinfo_op = {
  1010. .start =c_start,
  1011. .next = c_next,
  1012. .stop = c_stop,
  1013. .show = show_cpuinfo,
  1014. };