1 #include <linux/bootmem.h>
2 #include <linux/linkage.h>
3 #include <linux/bitops.h>
4 #include <linux/kernel.h>
5 #include <linux/module.h>
6 #include <linux/percpu.h>
7 #include <linux/string.h>
8 #include <linux/delay.h>
9 #include <linux/sched.h>
10 #include <linux/init.h>
11 #include <linux/kgdb.h>
12 #include <linux/smp.h>
15 #include <asm/stackprotector.h>
16 #include <asm/perf_event.h>
17 #include <asm/mmu_context.h>
18 #include <asm/archrandom.h>
19 #include <asm/hypervisor.h>
20 #include <asm/processor.h>
21 #include <asm/debugreg.h>
22 #include <asm/sections.h>
23 #include <linux/topology.h>
24 #include <linux/cpumask.h>
25 #include <asm/pgtable.h>
26 #include <linux/atomic.h>
27 #include <asm/proto.h>
28 #include <asm/setup.h>
32 #include <asm/fpu-internal.h>
34 #include <linux/numa.h>
40 #include <asm/microcode.h>
41 #include <asm/microcode_intel.h>
43 #ifdef CONFIG_X86_LOCAL_APIC
44 #include <asm/uv/uv.h>
49 /* all of these masks are initialized in setup_cpu_local_masks() */
50 cpumask_var_t cpu_initialized_mask;
51 cpumask_var_t cpu_callout_mask;
52 cpumask_var_t cpu_callin_mask;
54 /* representing cpus for which sibling maps can be computed */
55 cpumask_var_t cpu_sibling_setup_mask;
57 /* correctly size the local cpu masks */
58 void __init setup_cpu_local_masks(void)
60 alloc_bootmem_cpumask_var(&cpu_initialized_mask);
61 alloc_bootmem_cpumask_var(&cpu_callin_mask);
62 alloc_bootmem_cpumask_var(&cpu_callout_mask);
63 alloc_bootmem_cpumask_var(&cpu_sibling_setup_mask);
66 static void __cpuinit default_init(struct cpuinfo_x86 *c)
69 cpu_detect_cache_sizes(c);
71 /* Not much we can do here... */
72 /* Check if at least it has cpuid */
73 if (c->cpuid_level == -1) {
74 /* No cpuid. It must be an ancient CPU */
76 strcpy(c->x86_model_id, "486");
78 strcpy(c->x86_model_id, "386");
83 static const struct cpu_dev __cpuinitconst default_cpu = {
84 .c_init = default_init,
85 .c_vendor = "Unknown",
86 .c_x86_vendor = X86_VENDOR_UNKNOWN,
89 static const struct cpu_dev *this_cpu __cpuinitdata = &default_cpu;
91 DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
94 * We need valid kernel segments for data and code in long mode too
95 * IRET will check the segment types kkeil 2000/10/28
96 * Also sysret mandates a special GDT layout
98 * TLS descriptors are currently at a different place compared to i386.
99 * Hopefully nobody expects them at a fixed place (Wine?)
101 [GDT_ENTRY_KERNEL32_CS] = GDT_ENTRY_INIT(0xc09b, 0, 0xfffff),
102 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xa09b, 0, 0xfffff),
103 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc093, 0, 0xfffff),
104 [GDT_ENTRY_DEFAULT_USER32_CS] = GDT_ENTRY_INIT(0xc0fb, 0, 0xfffff),
105 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f3, 0, 0xfffff),
106 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xa0fb, 0, 0xfffff),
108 [GDT_ENTRY_KERNEL_CS] = GDT_ENTRY_INIT(0xc09a, 0, 0xfffff),
109 [GDT_ENTRY_KERNEL_DS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
110 [GDT_ENTRY_DEFAULT_USER_CS] = GDT_ENTRY_INIT(0xc0fa, 0, 0xfffff),
111 [GDT_ENTRY_DEFAULT_USER_DS] = GDT_ENTRY_INIT(0xc0f2, 0, 0xfffff),
113 * Segments used for calling PnP BIOS have byte granularity.
114 * They code segments and data segments have fixed 64k limits,
115 * the transfer segment sizes are set at run time.
118 [GDT_ENTRY_PNPBIOS_CS32] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
120 [GDT_ENTRY_PNPBIOS_CS16] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
122 [GDT_ENTRY_PNPBIOS_DS] = GDT_ENTRY_INIT(0x0092, 0, 0xffff),
124 [GDT_ENTRY_PNPBIOS_TS1] = GDT_ENTRY_INIT(0x0092, 0, 0),
126 [GDT_ENTRY_PNPBIOS_TS2] = GDT_ENTRY_INIT(0x0092, 0, 0),
128 * The APM segments have byte granularity and their bases
129 * are set at run time. All have 64k limits.
132 [GDT_ENTRY_APMBIOS_BASE] = GDT_ENTRY_INIT(0x409a, 0, 0xffff),
134 [GDT_ENTRY_APMBIOS_BASE+1] = GDT_ENTRY_INIT(0x009a, 0, 0xffff),
136 [GDT_ENTRY_APMBIOS_BASE+2] = GDT_ENTRY_INIT(0x4092, 0, 0xffff),
138 [GDT_ENTRY_ESPFIX_SS] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
139 [GDT_ENTRY_PERCPU] = GDT_ENTRY_INIT(0xc092, 0, 0xfffff),
140 GDT_STACK_CANARY_INIT
143 EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
145 static int __init x86_xsave_setup(char *s)
147 setup_clear_cpu_cap(X86_FEATURE_XSAVE);
148 setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
149 setup_clear_cpu_cap(X86_FEATURE_AVX);
150 setup_clear_cpu_cap(X86_FEATURE_AVX2);
153 __setup("noxsave", x86_xsave_setup);
155 static int __init x86_xsaveopt_setup(char *s)
157 setup_clear_cpu_cap(X86_FEATURE_XSAVEOPT);
160 __setup("noxsaveopt", x86_xsaveopt_setup);
163 static int cachesize_override __cpuinitdata = -1;
164 static int disable_x86_serial_nr __cpuinitdata = 1;
166 static int __init cachesize_setup(char *str)
168 get_option(&str, &cachesize_override);
171 __setup("cachesize=", cachesize_setup);
173 static int __init x86_fxsr_setup(char *s)
175 setup_clear_cpu_cap(X86_FEATURE_FXSR);
176 setup_clear_cpu_cap(X86_FEATURE_XMM);
179 __setup("nofxsr", x86_fxsr_setup);
181 static int __init x86_sep_setup(char *s)
183 setup_clear_cpu_cap(X86_FEATURE_SEP);
186 __setup("nosep", x86_sep_setup);
188 /* Standard macro to see if a specific flag is changeable */
189 static inline int flag_is_changeable_p(u32 flag)
194 * Cyrix and IDT cpus allow disabling of CPUID
195 * so the code below may return different results
196 * when it is executed before and after enabling
197 * the CPUID. Add "volatile" to not allow gcc to
198 * optimize the subsequent calls to this function.
200 asm volatile ("pushfl \n\t"
211 : "=&r" (f1), "=&r" (f2)
214 return ((f1^f2) & flag) != 0;
217 /* Probe for the CPUID instruction */
218 int __cpuinit have_cpuid_p(void)
220 return flag_is_changeable_p(X86_EFLAGS_ID);
223 static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
225 unsigned long lo, hi;
227 if (!cpu_has(c, X86_FEATURE_PN) || !disable_x86_serial_nr)
230 /* Disable processor serial number: */
232 rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
234 wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
236 printk(KERN_NOTICE "CPU serial number disabled.\n");
237 clear_cpu_cap(c, X86_FEATURE_PN);
239 /* Disabling the serial number may affect the cpuid level */
240 c->cpuid_level = cpuid_eax(0);
243 static int __init x86_serial_nr_setup(char *s)
245 disable_x86_serial_nr = 0;
248 __setup("serialnumber", x86_serial_nr_setup);
250 static inline int flag_is_changeable_p(u32 flag)
254 static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
259 static __init int setup_disable_smep(char *arg)
261 setup_clear_cpu_cap(X86_FEATURE_SMEP);
264 __setup("nosmep", setup_disable_smep);
266 static __always_inline void setup_smep(struct cpuinfo_x86 *c)
268 if (cpu_has(c, X86_FEATURE_SMEP))
269 set_in_cr4(X86_CR4_SMEP);
272 static __init int setup_disable_smap(char *arg)
274 setup_clear_cpu_cap(X86_FEATURE_SMAP);
277 __setup("nosmap", setup_disable_smap);
279 static __always_inline void setup_smap(struct cpuinfo_x86 *c)
281 unsigned long eflags;
283 /* This should have been cleared long ago */
284 raw_local_save_flags(eflags);
285 BUG_ON(eflags & X86_EFLAGS_AC);
287 if (cpu_has(c, X86_FEATURE_SMAP))
288 set_in_cr4(X86_CR4_SMAP);
292 * Some CPU features depend on higher CPUID levels, which may not always
293 * be available due to CPUID level capping or broken virtualization
294 * software. Add those features to this table to auto-disable them.
296 struct cpuid_dependent_feature {
301 static const struct cpuid_dependent_feature __cpuinitconst
302 cpuid_dependent_features[] = {
303 { X86_FEATURE_MWAIT, 0x00000005 },
304 { X86_FEATURE_DCA, 0x00000009 },
305 { X86_FEATURE_XSAVE, 0x0000000d },
309 static void __cpuinit filter_cpuid_features(struct cpuinfo_x86 *c, bool warn)
311 const struct cpuid_dependent_feature *df;
313 for (df = cpuid_dependent_features; df->feature; df++) {
315 if (!cpu_has(c, df->feature))
318 * Note: cpuid_level is set to -1 if unavailable, but
319 * extended_extended_level is set to 0 if unavailable
320 * and the legitimate extended levels are all negative
321 * when signed; hence the weird messing around with
324 if (!((s32)df->level < 0 ?
325 (u32)df->level > (u32)c->extended_cpuid_level :
326 (s32)df->level > (s32)c->cpuid_level))
329 clear_cpu_cap(c, df->feature);
334 "CPU: CPU feature %s disabled, no CPUID level 0x%x\n",
335 x86_cap_flags[df->feature], df->level);
340 * Naming convention should be: <Name> [(<Codename>)]
341 * This table only is used unless init_<vendor>() below doesn't set it;
342 * in particular, if CPUID levels 0x80000002..4 are supported, this
346 /* Look up CPU names by table lookup. */
347 static const char *__cpuinit table_lookup_model(struct cpuinfo_x86 *c)
349 const struct cpu_model_info *info;
351 if (c->x86_model >= 16)
352 return NULL; /* Range check */
357 info = this_cpu->c_models;
359 while (info && info->family) {
360 if (info->family == c->x86)
361 return info->model_names[c->x86_model];
364 return NULL; /* Not found */
367 __u32 cpu_caps_cleared[NCAPINTS] __cpuinitdata;
368 __u32 cpu_caps_set[NCAPINTS] __cpuinitdata;
370 void load_percpu_segment(int cpu)
373 loadsegment(fs, __KERNEL_PERCPU);
376 wrmsrl(MSR_GS_BASE, (unsigned long)per_cpu(irq_stack_union.gs_base, cpu));
378 load_stack_canary_segment();
382 * Current gdt points %fs at the "master" per-cpu area: after this,
383 * it's on the real one.
385 void switch_to_new_gdt(int cpu)
387 struct desc_ptr gdt_descr;
389 gdt_descr.address = (long)get_cpu_gdt_table(cpu);
390 gdt_descr.size = GDT_SIZE - 1;
391 load_gdt(&gdt_descr);
392 /* Reload the per-cpu base */
394 load_percpu_segment(cpu);
397 static const struct cpu_dev *__cpuinitdata cpu_devs[X86_VENDOR_NUM] = {};
399 static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
404 if (c->extended_cpuid_level < 0x80000004)
407 v = (unsigned int *)c->x86_model_id;
408 cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
409 cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
410 cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
411 c->x86_model_id[48] = 0;
414 * Intel chips right-justify this string for some dumb reason;
415 * undo that brain damage:
417 p = q = &c->x86_model_id[0];
423 while (q <= &c->x86_model_id[48])
424 *q++ = '\0'; /* Zero-pad the rest */
428 void __cpuinit cpu_detect_cache_sizes(struct cpuinfo_x86 *c)
430 unsigned int n, dummy, ebx, ecx, edx, l2size;
432 n = c->extended_cpuid_level;
434 if (n >= 0x80000005) {
435 cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
436 c->x86_cache_size = (ecx>>24) + (edx>>24);
438 /* On K8 L1 TLB is inclusive, so don't count it */
443 if (n < 0x80000006) /* Some chips just has a large L1. */
446 cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
450 c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
452 /* do processor-specific cache resizing */
453 if (this_cpu->c_size_cache)
454 l2size = this_cpu->c_size_cache(c, l2size);
456 /* Allow user to override all this if necessary. */
457 if (cachesize_override != -1)
458 l2size = cachesize_override;
461 return; /* Again, no L2 cache is possible */
464 c->x86_cache_size = l2size;
467 u16 __read_mostly tlb_lli_4k[NR_INFO];
468 u16 __read_mostly tlb_lli_2m[NR_INFO];
469 u16 __read_mostly tlb_lli_4m[NR_INFO];
470 u16 __read_mostly tlb_lld_4k[NR_INFO];
471 u16 __read_mostly tlb_lld_2m[NR_INFO];
472 u16 __read_mostly tlb_lld_4m[NR_INFO];
475 * tlb_flushall_shift shows the balance point in replacing cr3 write
476 * with multiple 'invlpg'. It will do this replacement when
477 * flush_tlb_lines <= active_lines/2^tlb_flushall_shift.
478 * If tlb_flushall_shift is -1, means the replacement will be disabled.
480 s8 __read_mostly tlb_flushall_shift = -1;
482 void __cpuinit cpu_detect_tlb(struct cpuinfo_x86 *c)
484 if (this_cpu->c_detect_tlb)
485 this_cpu->c_detect_tlb(c);
487 printk(KERN_INFO "Last level iTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \
488 "Last level dTLB entries: 4KB %d, 2MB %d, 4MB %d\n" \
489 "tlb_flushall_shift: %d\n",
490 tlb_lli_4k[ENTRIES], tlb_lli_2m[ENTRIES],
491 tlb_lli_4m[ENTRIES], tlb_lld_4k[ENTRIES],
492 tlb_lld_2m[ENTRIES], tlb_lld_4m[ENTRIES],
496 void __cpuinit detect_ht(struct cpuinfo_x86 *c)
499 u32 eax, ebx, ecx, edx;
500 int index_msb, core_bits;
503 if (!cpu_has(c, X86_FEATURE_HT))
506 if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
509 if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
512 cpuid(1, &eax, &ebx, &ecx, &edx);
514 smp_num_siblings = (ebx & 0xff0000) >> 16;
516 if (smp_num_siblings == 1) {
517 printk_once(KERN_INFO "CPU0: Hyper-Threading is disabled\n");
521 if (smp_num_siblings <= 1)
524 index_msb = get_count_order(smp_num_siblings);
525 c->phys_proc_id = apic->phys_pkg_id(c->initial_apicid, index_msb);
527 smp_num_siblings = smp_num_siblings / c->x86_max_cores;
529 index_msb = get_count_order(smp_num_siblings);
531 core_bits = get_count_order(c->x86_max_cores);
533 c->cpu_core_id = apic->phys_pkg_id(c->initial_apicid, index_msb) &
534 ((1 << core_bits) - 1);
537 if (!printed && (c->x86_max_cores * smp_num_siblings) > 1) {
538 printk(KERN_INFO "CPU: Physical Processor ID: %d\n",
540 printk(KERN_INFO "CPU: Processor Core ID: %d\n",
547 static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
549 char *v = c->x86_vendor_id;
552 for (i = 0; i < X86_VENDOR_NUM; i++) {
556 if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
557 (cpu_devs[i]->c_ident[1] &&
558 !strcmp(v, cpu_devs[i]->c_ident[1]))) {
560 this_cpu = cpu_devs[i];
561 c->x86_vendor = this_cpu->c_x86_vendor;
567 "CPU: vendor_id '%s' unknown, using generic init.\n" \
568 "CPU: Your system may be unstable.\n", v);
570 c->x86_vendor = X86_VENDOR_UNKNOWN;
571 this_cpu = &default_cpu;
574 void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
576 /* Get vendor name */
577 cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
578 (unsigned int *)&c->x86_vendor_id[0],
579 (unsigned int *)&c->x86_vendor_id[8],
580 (unsigned int *)&c->x86_vendor_id[4]);
583 /* Intel-defined flags: level 0x00000001 */
584 if (c->cpuid_level >= 0x00000001) {
585 u32 junk, tfms, cap0, misc;
587 cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
588 c->x86 = (tfms >> 8) & 0xf;
589 c->x86_model = (tfms >> 4) & 0xf;
590 c->x86_mask = tfms & 0xf;
593 c->x86 += (tfms >> 20) & 0xff;
595 c->x86_model += ((tfms >> 16) & 0xf) << 4;
597 if (cap0 & (1<<19)) {
598 c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
599 c->x86_cache_alignment = c->x86_clflush_size;
604 void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
609 /* Intel-defined flags: level 0x00000001 */
610 if (c->cpuid_level >= 0x00000001) {
611 u32 capability, excap;
613 cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
614 c->x86_capability[0] = capability;
615 c->x86_capability[4] = excap;
618 /* Additional Intel-defined flags: level 0x00000007 */
619 if (c->cpuid_level >= 0x00000007) {
620 u32 eax, ebx, ecx, edx;
622 cpuid_count(0x00000007, 0, &eax, &ebx, &ecx, &edx);
624 c->x86_capability[9] = ebx;
627 /* AMD-defined flags: level 0x80000001 */
628 xlvl = cpuid_eax(0x80000000);
629 c->extended_cpuid_level = xlvl;
631 if ((xlvl & 0xffff0000) == 0x80000000) {
632 if (xlvl >= 0x80000001) {
633 c->x86_capability[1] = cpuid_edx(0x80000001);
634 c->x86_capability[6] = cpuid_ecx(0x80000001);
638 if (c->extended_cpuid_level >= 0x80000008) {
639 u32 eax = cpuid_eax(0x80000008);
641 c->x86_virt_bits = (eax >> 8) & 0xff;
642 c->x86_phys_bits = eax & 0xff;
645 else if (cpu_has(c, X86_FEATURE_PAE) || cpu_has(c, X86_FEATURE_PSE36))
646 c->x86_phys_bits = 36;
649 if (c->extended_cpuid_level >= 0x80000007)
650 c->x86_power = cpuid_edx(0x80000007);
652 init_scattered_cpuid_features(c);
655 static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
661 * First of all, decide if this is a 486 or higher
662 * It's a 486 if we can modify the AC flag
664 if (flag_is_changeable_p(X86_EFLAGS_AC))
669 for (i = 0; i < X86_VENDOR_NUM; i++)
670 if (cpu_devs[i] && cpu_devs[i]->c_identify) {
671 c->x86_vendor_id[0] = 0;
672 cpu_devs[i]->c_identify(c);
673 if (c->x86_vendor_id[0]) {
682 * Do minimum CPU detection early.
683 * Fields really needed: vendor, cpuid_level, family, model, mask,
685 * The others are not touched to avoid unwanted side effects.
687 * WARNING: this function is only called on the BP. Don't add code here
688 * that is supposed to run on all CPUs.
690 static void __init early_identify_cpu(struct cpuinfo_x86 *c)
693 c->x86_clflush_size = 64;
694 c->x86_phys_bits = 36;
695 c->x86_virt_bits = 48;
697 c->x86_clflush_size = 32;
698 c->x86_phys_bits = 32;
699 c->x86_virt_bits = 32;
701 c->x86_cache_alignment = c->x86_clflush_size;
703 memset(&c->x86_capability, 0, sizeof c->x86_capability);
704 c->extended_cpuid_level = 0;
707 identify_cpu_without_cpuid(c);
709 /* cyrix could have cpuid enabled via c_identify()*/
718 if (this_cpu->c_early_init)
719 this_cpu->c_early_init(c);
722 filter_cpuid_features(c, false);
724 if (this_cpu->c_bsp_init)
725 this_cpu->c_bsp_init(c);
727 setup_force_cpu_cap(X86_FEATURE_ALWAYS);
730 void __init early_cpu_init(void)
732 const struct cpu_dev *const *cdev;
735 #ifdef CONFIG_PROCESSOR_SELECT
736 printk(KERN_INFO "KERNEL supported cpus:\n");
739 for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
740 const struct cpu_dev *cpudev = *cdev;
742 if (count >= X86_VENDOR_NUM)
744 cpu_devs[count] = cpudev;
747 #ifdef CONFIG_PROCESSOR_SELECT
751 for (j = 0; j < 2; j++) {
752 if (!cpudev->c_ident[j])
754 printk(KERN_INFO " %s %s\n", cpudev->c_vendor,
760 early_identify_cpu(&boot_cpu_data);
764 * The NOPL instruction is supposed to exist on all CPUs of family >= 6;
765 * unfortunately, that's not true in practice because of early VIA
766 * chips and (more importantly) broken virtualizers that are not easy
767 * to detect. In the latter case it doesn't even *fail* reliably, so
768 * probing for it doesn't even work. Disable it completely on 32-bit
769 * unless we can find a reliable way to detect all the broken cases.
770 * Enable it explicitly on 64-bit for non-constant inputs of cpu_has().
772 static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
775 clear_cpu_cap(c, X86_FEATURE_NOPL);
777 set_cpu_cap(c, X86_FEATURE_NOPL);
781 static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
783 c->extended_cpuid_level = 0;
786 identify_cpu_without_cpuid(c);
788 /* cyrix could have cpuid enabled via c_identify()*/
798 if (c->cpuid_level >= 0x00000001) {
799 c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
801 # ifdef CONFIG_X86_HT
802 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
804 c->apicid = c->initial_apicid;
807 c->phys_proc_id = c->initial_apicid;
810 get_model_name(c); /* Default name */
816 * This does the hard work of actually picking apart the CPU stuff...
818 static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
822 c->loops_per_jiffy = loops_per_jiffy;
823 c->x86_cache_size = -1;
824 c->x86_vendor = X86_VENDOR_UNKNOWN;
825 c->x86_model = c->x86_mask = 0; /* So far unknown... */
826 c->x86_vendor_id[0] = '\0'; /* Unset */
827 c->x86_model_id[0] = '\0'; /* Unset */
828 c->x86_max_cores = 1;
829 c->x86_coreid_bits = 0;
831 c->x86_clflush_size = 64;
832 c->x86_phys_bits = 36;
833 c->x86_virt_bits = 48;
835 c->cpuid_level = -1; /* CPUID not detected */
836 c->x86_clflush_size = 32;
837 c->x86_phys_bits = 32;
838 c->x86_virt_bits = 32;
840 c->x86_cache_alignment = c->x86_clflush_size;
841 memset(&c->x86_capability, 0, sizeof c->x86_capability);
845 if (this_cpu->c_identify)
846 this_cpu->c_identify(c);
848 /* Clear/Set all flags overriden by options, after probe */
849 for (i = 0; i < NCAPINTS; i++) {
850 c->x86_capability[i] &= ~cpu_caps_cleared[i];
851 c->x86_capability[i] |= cpu_caps_set[i];
855 c->apicid = apic->phys_pkg_id(c->initial_apicid, 0);
859 * Vendor-specific initialization. In this section we
860 * canonicalize the feature flags, meaning if there are
861 * features a certain CPU supports which CPUID doesn't
862 * tell us, CPUID claiming incorrect flags, or other bugs,
863 * we handle them here.
865 * At the end of this section, c->x86_capability better
866 * indicate the features this CPU genuinely supports!
868 if (this_cpu->c_init)
871 /* Disable the PN if appropriate */
872 squash_the_stupid_serial_number(c);
874 /* Set up SMEP/SMAP */
879 * The vendor-specific functions might have changed features.
880 * Now we do "generic changes."
883 /* Filter out anything that depends on CPUID levels we don't have */
884 filter_cpuid_features(c, true);
886 /* If the model name is still unset, do table lookup. */
887 if (!c->x86_model_id[0]) {
889 p = table_lookup_model(c);
891 strcpy(c->x86_model_id, p);
894 sprintf(c->x86_model_id, "%02x/%02x",
895 c->x86, c->x86_model);
906 * Clear/Set all flags overriden by options, need do it
907 * before following smp all cpus cap AND.
909 for (i = 0; i < NCAPINTS; i++) {
910 c->x86_capability[i] &= ~cpu_caps_cleared[i];
911 c->x86_capability[i] |= cpu_caps_set[i];
915 * On SMP, boot_cpu_data holds the common feature set between
916 * all CPUs; so make sure that we indicate which features are
917 * common between the CPUs. The first time this routine gets
918 * executed, c == &boot_cpu_data.
920 if (c != &boot_cpu_data) {
921 /* AND the already accumulated flags with these */
922 for (i = 0; i < NCAPINTS; i++)
923 boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
925 /* OR, i.e. replicate the bug flags */
926 for (i = NCAPINTS; i < NCAPINTS + NBUGINTS; i++)
927 c->x86_capability[i] |= boot_cpu_data.x86_capability[i];
930 /* Init Machine Check Exception if available. */
933 select_idle_routine(c);
936 numa_add_cpu(smp_processor_id());
941 static void vgetcpu_set_mode(void)
943 if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
944 vgetcpu_mode = VGETCPU_RDTSCP;
946 vgetcpu_mode = VGETCPU_LSL;
950 void __init identify_boot_cpu(void)
952 identify_cpu(&boot_cpu_data);
953 init_amd_e400_c1e_mask();
960 cpu_detect_tlb(&boot_cpu_data);
963 void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
965 BUG_ON(c == &boot_cpu_data);
978 static const struct msr_range msr_range_array[] __cpuinitconst = {
979 { 0x00000000, 0x00000418},
980 { 0xc0000000, 0xc000040b},
981 { 0xc0010000, 0xc0010142},
982 { 0xc0011000, 0xc001103b},
985 static void __cpuinit __print_cpu_msr(void)
987 unsigned index_min, index_max;
992 for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
993 index_min = msr_range_array[i].min;
994 index_max = msr_range_array[i].max;
996 for (index = index_min; index < index_max; index++) {
997 if (rdmsrl_safe(index, &val))
999 printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
1004 static int show_msr __cpuinitdata;
1006 static __init int setup_show_msr(char *arg)
1010 get_option(&arg, &num);
1016 __setup("show_msr=", setup_show_msr);
1018 static __init int setup_noclflush(char *arg)
1020 setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
1023 __setup("noclflush", setup_noclflush);
1025 void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
1027 const char *vendor = NULL;
1029 if (c->x86_vendor < X86_VENDOR_NUM) {
1030 vendor = this_cpu->c_vendor;
1032 if (c->cpuid_level >= 0)
1033 vendor = c->x86_vendor_id;
1036 if (vendor && !strstr(c->x86_model_id, vendor))
1037 printk(KERN_CONT "%s ", vendor);
1039 if (c->x86_model_id[0])
1040 printk(KERN_CONT "%s", strim(c->x86_model_id));
1042 printk(KERN_CONT "%d86", c->x86);
1044 printk(KERN_CONT " (fam: %02x, model: %02x", c->x86, c->x86_model);
1046 if (c->x86_mask || c->cpuid_level >= 0)
1047 printk(KERN_CONT ", stepping: %02x)\n", c->x86_mask);
1049 printk(KERN_CONT ")\n");
1054 void __cpuinit print_cpu_msr(struct cpuinfo_x86 *c)
1056 if (c->cpu_index < show_msr)
1060 static __init int setup_disablecpuid(char *arg)
1064 if (get_option(&arg, &bit) && bit < NCAPINTS*32)
1065 setup_clear_cpu_cap(bit);
1071 __setup("clearcpuid=", setup_disablecpuid);
1073 #ifdef CONFIG_X86_64
1074 struct desc_ptr idt_descr = { NR_VECTORS * 16 - 1, (unsigned long) idt_table };
1075 struct desc_ptr debug_idt_descr = { NR_VECTORS * 16 - 1,
1076 (unsigned long) debug_idt_table };
1078 DEFINE_PER_CPU_FIRST(union irq_stack_union,
1079 irq_stack_union) __aligned(PAGE_SIZE);
1082 * The following four percpu variables are hot. Align current_task to
1083 * cacheline size such that all four fall in the same cacheline.
1085 DEFINE_PER_CPU(struct task_struct *, current_task) ____cacheline_aligned =
1087 EXPORT_PER_CPU_SYMBOL(current_task);
1089 DEFINE_PER_CPU(unsigned long, kernel_stack) =
1090 (unsigned long)&init_thread_union - KERNEL_STACK_OFFSET + THREAD_SIZE;
1091 EXPORT_PER_CPU_SYMBOL(kernel_stack);
1093 DEFINE_PER_CPU(char *, irq_stack_ptr) =
1094 init_per_cpu_var(irq_stack_union.irq_stack) + IRQ_STACK_SIZE - 64;
1096 DEFINE_PER_CPU(unsigned int, irq_count) = -1;
1098 DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
1101 * Special IST stacks which the CPU switches to when it calls
1102 * an IST-marked descriptor entry. Up to 7 stacks (hardware
1103 * limit), all of them are 4K, except the debug stack which
1106 static const unsigned int exception_stack_sizes[N_EXCEPTION_STACKS] = {
1107 [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STKSZ,
1108 [DEBUG_STACK - 1] = DEBUG_STKSZ
1111 static DEFINE_PER_CPU_PAGE_ALIGNED(char, exception_stacks
1112 [(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ + DEBUG_STKSZ]);
1114 /* May not be marked __init: used by software suspend */
1115 void syscall_init(void)
1118 * LSTAR and STAR live in a bit strange symbiosis.
1119 * They both write to the same internal register. STAR allows to
1120 * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
1122 wrmsrl(MSR_STAR, ((u64)__USER32_CS)<<48 | ((u64)__KERNEL_CS)<<32);
1123 wrmsrl(MSR_LSTAR, system_call);
1124 wrmsrl(MSR_CSTAR, ignore_sysret);
1126 #ifdef CONFIG_IA32_EMULATION
1127 syscall32_cpu_init();
1130 /* Flags to clear on syscall */
1131 wrmsrl(MSR_SYSCALL_MASK,
1132 X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|
1133 X86_EFLAGS_IOPL|X86_EFLAGS_AC);
1137 * Copies of the original ist values from the tss are only accessed during
1138 * debugging, no special alignment required.
1140 DEFINE_PER_CPU(struct orig_ist, orig_ist);
1142 static DEFINE_PER_CPU(unsigned long, debug_stack_addr);
1143 DEFINE_PER_CPU(int, debug_stack_usage);
1145 int is_debug_stack(unsigned long addr)
1147 return __get_cpu_var(debug_stack_usage) ||
1148 (addr <= __get_cpu_var(debug_stack_addr) &&
1149 addr > (__get_cpu_var(debug_stack_addr) - DEBUG_STKSZ));
1152 DEFINE_PER_CPU(u32, debug_idt_ctr);
1154 void debug_stack_set_zero(void)
1156 this_cpu_inc(debug_idt_ctr);
1160 void debug_stack_reset(void)
1162 if (WARN_ON(!this_cpu_read(debug_idt_ctr)))
1164 if (this_cpu_dec_return(debug_idt_ctr) == 0)
1168 #else /* CONFIG_X86_64 */
1170 DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
1171 EXPORT_PER_CPU_SYMBOL(current_task);
1172 DEFINE_PER_CPU(struct task_struct *, fpu_owner_task);
1174 #ifdef CONFIG_CC_STACKPROTECTOR
1175 DEFINE_PER_CPU_ALIGNED(struct stack_canary, stack_canary);
1178 #endif /* CONFIG_X86_64 */
1181 * Clear all 6 debug registers:
1183 static void clear_all_debug_regs(void)
1187 for (i = 0; i < 8; i++) {
1188 /* Ignore db4, db5 */
1189 if ((i == 4) || (i == 5))
1198 * Restore debug regs if using kgdbwait and you have a kernel debugger
1199 * connection established.
1201 static void dbg_restore_debug_regs(void)
1203 if (unlikely(kgdb_connected && arch_kgdb_ops.correct_hw_break))
1204 arch_kgdb_ops.correct_hw_break();
1206 #else /* ! CONFIG_KGDB */
1207 #define dbg_restore_debug_regs()
1208 #endif /* ! CONFIG_KGDB */
1211 * cpu_init() initializes state that is per-CPU. Some data is already
1212 * initialized (naturally) in the bootstrap process, such as the GDT
1213 * and IDT. We reload them nevertheless, this function acts as a
1214 * 'CPU state barrier', nothing should get across.
1215 * A lot of state is already set up in PDA init for 64 bit
1217 #ifdef CONFIG_X86_64
1219 void __cpuinit cpu_init(void)
1221 struct orig_ist *oist;
1222 struct task_struct *me;
1223 struct tss_struct *t;
1229 * Load microcode on this cpu if a valid microcode is available.
1230 * This is early microcode loading procedure.
1234 cpu = stack_smp_processor_id();
1235 t = &per_cpu(init_tss, cpu);
1236 oist = &per_cpu(orig_ist, cpu);
1239 if (this_cpu_read(numa_node) == 0 &&
1240 early_cpu_to_node(cpu) != NUMA_NO_NODE)
1241 set_numa_node(early_cpu_to_node(cpu));
1246 if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask))
1247 panic("CPU#%d already initialized!\n", cpu);
1249 pr_debug("Initializing CPU#%d\n", cpu);
1251 clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1254 * Initialize the per-CPU GDT with the boot GDT,
1255 * and set up the GDT descriptor:
1258 switch_to_new_gdt(cpu);
1263 memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
1266 wrmsrl(MSR_FS_BASE, 0);
1267 wrmsrl(MSR_KERNEL_GS_BASE, 0);
1274 * set up and load the per-CPU TSS
1276 if (!oist->ist[0]) {
1277 char *estacks = per_cpu(exception_stacks, cpu);
1279 for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1280 estacks += exception_stack_sizes[v];
1281 oist->ist[v] = t->x86_tss.ist[v] =
1282 (unsigned long)estacks;
1283 if (v == DEBUG_STACK-1)
1284 per_cpu(debug_stack_addr, cpu) = (unsigned long)estacks;
1288 t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1291 * <= is required because the CPU will access up to
1292 * 8 bits beyond the end of the IO permission bitmap.
1294 for (i = 0; i <= IO_BITMAP_LONGS; i++)
1295 t->io_bitmap[i] = ~0UL;
1297 atomic_inc(&init_mm.mm_count);
1298 me->active_mm = &init_mm;
1300 enter_lazy_tlb(&init_mm, me);
1302 load_sp0(t, ¤t->thread);
1303 set_tss_desc(cpu, t);
1305 load_LDT(&init_mm.context);
1307 clear_all_debug_regs();
1308 dbg_restore_debug_regs();
1318 void __cpuinit cpu_init(void)
1320 int cpu = smp_processor_id();
1321 struct task_struct *curr = current;
1322 struct tss_struct *t = &per_cpu(init_tss, cpu);
1323 struct thread_struct *thread = &curr->thread;
1325 show_ucode_info_early();
1327 if (cpumask_test_and_set_cpu(cpu, cpu_initialized_mask)) {
1328 printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
1333 printk(KERN_INFO "Initializing CPU#%d\n", cpu);
1335 if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
1336 clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1339 switch_to_new_gdt(cpu);
1342 * Set up and load the per-CPU TSS and LDT
1344 atomic_inc(&init_mm.mm_count);
1345 curr->active_mm = &init_mm;
1347 enter_lazy_tlb(&init_mm, curr);
1349 load_sp0(t, thread);
1350 set_tss_desc(cpu, t);
1352 load_LDT(&init_mm.context);
1354 t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1356 #ifdef CONFIG_DOUBLEFAULT
1357 /* Set up doublefault TSS pointer in the GDT */
1358 __set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1361 clear_all_debug_regs();
1362 dbg_restore_debug_regs();
1368 #ifdef CONFIG_X86_DEBUG_STATIC_CPU_HAS
1369 void warn_pre_alternatives(void)
1371 WARN(1, "You're using static_cpu_has before alternatives have run!\n");
1373 EXPORT_SYMBOL_GPL(warn_pre_alternatives);
1376 inline bool __static_cpu_has_safe(u16 bit)
1378 return boot_cpu_has(bit);
1380 EXPORT_SYMBOL_GPL(__static_cpu_has_safe);