xref: /linux/arch/x86/kernel/cpu/common.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
1 #include <linux/init.h>
2 #include <linux/kernel.h>
3 #include <linux/sched.h>
4 #include <linux/string.h>
5 #include <linux/bootmem.h>
6 #include <linux/bitops.h>
7 #include <linux/module.h>
8 #include <linux/kgdb.h>
9 #include <linux/topology.h>
10 #include <linux/delay.h>
11 #include <linux/smp.h>
12 #include <linux/percpu.h>
13 #include <asm/i387.h>
14 #include <asm/msr.h>
15 #include <asm/io.h>
16 #include <asm/linkage.h>
17 #include <asm/mmu_context.h>
18 #include <asm/mtrr.h>
19 #include <asm/mce.h>
20 #include <asm/pat.h>
21 #include <asm/asm.h>
22 #include <asm/numa.h>
23 #include <asm/smp.h>
24 #ifdef CONFIG_X86_LOCAL_APIC
25 #include <asm/mpspec.h>
26 #include <asm/apic.h>
27 #include <mach_apic.h>
28 #include <asm/genapic.h>
29 #endif
30 
31 #include <asm/pda.h>
32 #include <asm/pgtable.h>
33 #include <asm/processor.h>
34 #include <asm/desc.h>
35 #include <asm/atomic.h>
36 #include <asm/proto.h>
37 #include <asm/sections.h>
38 #include <asm/setup.h>
39 
40 #include "cpu.h"
41 
42 static struct cpu_dev *this_cpu __cpuinitdata;
43 
44 #ifdef CONFIG_X86_64
45 /* We need valid kernel segments for data and code in long mode too
46  * IRET will check the segment types  kkeil 2000/10/28
47  * Also sysret mandates a special GDT layout
48  */
49 /* The TLS descriptors are currently at a different place compared to i386.
50    Hopefully nobody expects them at a fixed place (Wine?) */
51 DEFINE_PER_CPU(struct gdt_page, gdt_page) = { .gdt = {
52 	[GDT_ENTRY_KERNEL32_CS] = { { { 0x0000ffff, 0x00cf9b00 } } },
53 	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00af9b00 } } },
54 	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9300 } } },
55 	[GDT_ENTRY_DEFAULT_USER32_CS] = { { { 0x0000ffff, 0x00cffb00 } } },
56 	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff300 } } },
57 	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00affb00 } } },
58 } };
59 #else
60 DEFINE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page) = { .gdt = {
61 	[GDT_ENTRY_KERNEL_CS] = { { { 0x0000ffff, 0x00cf9a00 } } },
62 	[GDT_ENTRY_KERNEL_DS] = { { { 0x0000ffff, 0x00cf9200 } } },
63 	[GDT_ENTRY_DEFAULT_USER_CS] = { { { 0x0000ffff, 0x00cffa00 } } },
64 	[GDT_ENTRY_DEFAULT_USER_DS] = { { { 0x0000ffff, 0x00cff200 } } },
65 	/*
66 	 * Segments used for calling PnP BIOS have byte granularity.
67 	 * They code segments and data segments have fixed 64k limits,
68 	 * the transfer segment sizes are set at run time.
69 	 */
70 	/* 32-bit code */
71 	[GDT_ENTRY_PNPBIOS_CS32] = { { { 0x0000ffff, 0x00409a00 } } },
72 	/* 16-bit code */
73 	[GDT_ENTRY_PNPBIOS_CS16] = { { { 0x0000ffff, 0x00009a00 } } },
74 	/* 16-bit data */
75 	[GDT_ENTRY_PNPBIOS_DS] = { { { 0x0000ffff, 0x00009200 } } },
76 	/* 16-bit data */
77 	[GDT_ENTRY_PNPBIOS_TS1] = { { { 0x00000000, 0x00009200 } } },
78 	/* 16-bit data */
79 	[GDT_ENTRY_PNPBIOS_TS2] = { { { 0x00000000, 0x00009200 } } },
80 	/*
81 	 * The APM segments have byte granularity and their bases
82 	 * are set at run time.  All have 64k limits.
83 	 */
84 	/* 32-bit code */
85 	[GDT_ENTRY_APMBIOS_BASE] = { { { 0x0000ffff, 0x00409a00 } } },
86 	/* 16-bit code */
87 	[GDT_ENTRY_APMBIOS_BASE+1] = { { { 0x0000ffff, 0x00009a00 } } },
88 	/* data */
89 	[GDT_ENTRY_APMBIOS_BASE+2] = { { { 0x0000ffff, 0x00409200 } } },
90 
91 	[GDT_ENTRY_ESPFIX_SS] = { { { 0x00000000, 0x00c09200 } } },
92 	[GDT_ENTRY_PERCPU] = { { { 0x00000000, 0x00000000 } } },
93 } };
94 #endif
95 EXPORT_PER_CPU_SYMBOL_GPL(gdt_page);
96 
97 #ifdef CONFIG_X86_32
98 static int cachesize_override __cpuinitdata = -1;
99 static int disable_x86_serial_nr __cpuinitdata = 1;
100 
101 static int __init cachesize_setup(char *str)
102 {
103 	get_option(&str, &cachesize_override);
104 	return 1;
105 }
106 __setup("cachesize=", cachesize_setup);
107 
108 static int __init x86_fxsr_setup(char *s)
109 {
110 	setup_clear_cpu_cap(X86_FEATURE_FXSR);
111 	setup_clear_cpu_cap(X86_FEATURE_XMM);
112 	return 1;
113 }
114 __setup("nofxsr", x86_fxsr_setup);
115 
116 static int __init x86_sep_setup(char *s)
117 {
118 	setup_clear_cpu_cap(X86_FEATURE_SEP);
119 	return 1;
120 }
121 __setup("nosep", x86_sep_setup);
122 
123 /* Standard macro to see if a specific flag is changeable */
124 static inline int flag_is_changeable_p(u32 flag)
125 {
126 	u32 f1, f2;
127 
128 	/*
129 	 * Cyrix and IDT cpus allow disabling of CPUID
130 	 * so the code below may return different results
131 	 * when it is executed before and after enabling
132 	 * the CPUID. Add "volatile" to not allow gcc to
133 	 * optimize the subsequent calls to this function.
134 	 */
135 	asm volatile ("pushfl\n\t"
136 		      "pushfl\n\t"
137 		      "popl %0\n\t"
138 		      "movl %0,%1\n\t"
139 		      "xorl %2,%0\n\t"
140 		      "pushl %0\n\t"
141 		      "popfl\n\t"
142 		      "pushfl\n\t"
143 		      "popl %0\n\t"
144 		      "popfl\n\t"
145 		      : "=&r" (f1), "=&r" (f2)
146 		      : "ir" (flag));
147 
148 	return ((f1^f2) & flag) != 0;
149 }
150 
151 /* Probe for the CPUID instruction */
152 static int __cpuinit have_cpuid_p(void)
153 {
154 	return flag_is_changeable_p(X86_EFLAGS_ID);
155 }
156 
157 static void __cpuinit squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
158 {
159 	if (cpu_has(c, X86_FEATURE_PN) && disable_x86_serial_nr) {
160 		/* Disable processor serial number */
161 		unsigned long lo, hi;
162 		rdmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
163 		lo |= 0x200000;
164 		wrmsr(MSR_IA32_BBL_CR_CTL, lo, hi);
165 		printk(KERN_NOTICE "CPU serial number disabled.\n");
166 		clear_cpu_cap(c, X86_FEATURE_PN);
167 
168 		/* Disabling the serial number may affect the cpuid level */
169 		c->cpuid_level = cpuid_eax(0);
170 	}
171 }
172 
173 static int __init x86_serial_nr_setup(char *s)
174 {
175 	disable_x86_serial_nr = 0;
176 	return 1;
177 }
178 __setup("serialnumber", x86_serial_nr_setup);
179 #else
180 static inline int flag_is_changeable_p(u32 flag)
181 {
182 	return 1;
183 }
184 /* Probe for the CPUID instruction */
185 static inline int have_cpuid_p(void)
186 {
187 	return 1;
188 }
189 static inline void squash_the_stupid_serial_number(struct cpuinfo_x86 *c)
190 {
191 }
192 #endif
193 
194 /*
195  * Naming convention should be: <Name> [(<Codename>)]
196  * This table only is used unless init_<vendor>() below doesn't set it;
197  * in particular, if CPUID levels 0x80000002..4 are supported, this isn't used
198  *
199  */
200 
201 /* Look up CPU names by table lookup. */
202 static char __cpuinit *table_lookup_model(struct cpuinfo_x86 *c)
203 {
204 	struct cpu_model_info *info;
205 
206 	if (c->x86_model >= 16)
207 		return NULL;	/* Range check */
208 
209 	if (!this_cpu)
210 		return NULL;
211 
212 	info = this_cpu->c_models;
213 
214 	while (info && info->family) {
215 		if (info->family == c->x86)
216 			return info->model_names[c->x86_model];
217 		info++;
218 	}
219 	return NULL;		/* Not found */
220 }
221 
222 __u32 cleared_cpu_caps[NCAPINTS] __cpuinitdata;
223 
224 /* Current gdt points %fs at the "master" per-cpu area: after this,
225  * it's on the real one. */
226 void switch_to_new_gdt(void)
227 {
228 	struct desc_ptr gdt_descr;
229 
230 	gdt_descr.address = (long)get_cpu_gdt_table(smp_processor_id());
231 	gdt_descr.size = GDT_SIZE - 1;
232 	load_gdt(&gdt_descr);
233 #ifdef CONFIG_X86_32
234 	asm("mov %0, %%fs" : : "r" (__KERNEL_PERCPU) : "memory");
235 #endif
236 }
237 
238 static struct cpu_dev *cpu_devs[X86_VENDOR_NUM] = {};
239 
240 static void __cpuinit default_init(struct cpuinfo_x86 *c)
241 {
242 #ifdef CONFIG_X86_64
243 	display_cacheinfo(c);
244 #else
245 	/* Not much we can do here... */
246 	/* Check if at least it has cpuid */
247 	if (c->cpuid_level == -1) {
248 		/* No cpuid. It must be an ancient CPU */
249 		if (c->x86 == 4)
250 			strcpy(c->x86_model_id, "486");
251 		else if (c->x86 == 3)
252 			strcpy(c->x86_model_id, "386");
253 	}
254 #endif
255 }
256 
257 static struct cpu_dev __cpuinitdata default_cpu = {
258 	.c_init	= default_init,
259 	.c_vendor = "Unknown",
260 	.c_x86_vendor = X86_VENDOR_UNKNOWN,
261 };
262 
263 static void __cpuinit get_model_name(struct cpuinfo_x86 *c)
264 {
265 	unsigned int *v;
266 	char *p, *q;
267 
268 	if (c->extended_cpuid_level < 0x80000004)
269 		return;
270 
271 	v = (unsigned int *) c->x86_model_id;
272 	cpuid(0x80000002, &v[0], &v[1], &v[2], &v[3]);
273 	cpuid(0x80000003, &v[4], &v[5], &v[6], &v[7]);
274 	cpuid(0x80000004, &v[8], &v[9], &v[10], &v[11]);
275 	c->x86_model_id[48] = 0;
276 
277 	/* Intel chips right-justify this string for some dumb reason;
278 	   undo that brain damage */
279 	p = q = &c->x86_model_id[0];
280 	while (*p == ' ')
281 	     p++;
282 	if (p != q) {
283 	     while (*p)
284 		  *q++ = *p++;
285 	     while (q <= &c->x86_model_id[48])
286 		  *q++ = '\0';	/* Zero-pad the rest */
287 	}
288 }
289 
290 void __cpuinit display_cacheinfo(struct cpuinfo_x86 *c)
291 {
292 	unsigned int n, dummy, ebx, ecx, edx, l2size;
293 
294 	n = c->extended_cpuid_level;
295 
296 	if (n >= 0x80000005) {
297 		cpuid(0x80000005, &dummy, &ebx, &ecx, &edx);
298 		printk(KERN_INFO "CPU: L1 I Cache: %dK (%d bytes/line), D cache %dK (%d bytes/line)\n",
299 				edx>>24, edx&0xFF, ecx>>24, ecx&0xFF);
300 		c->x86_cache_size = (ecx>>24) + (edx>>24);
301 #ifdef CONFIG_X86_64
302 		/* On K8 L1 TLB is inclusive, so don't count it */
303 		c->x86_tlbsize = 0;
304 #endif
305 	}
306 
307 	if (n < 0x80000006)	/* Some chips just has a large L1. */
308 		return;
309 
310 	cpuid(0x80000006, &dummy, &ebx, &ecx, &edx);
311 	l2size = ecx >> 16;
312 
313 #ifdef CONFIG_X86_64
314 	c->x86_tlbsize += ((ebx >> 16) & 0xfff) + (ebx & 0xfff);
315 #else
316 	/* do processor-specific cache resizing */
317 	if (this_cpu->c_size_cache)
318 		l2size = this_cpu->c_size_cache(c, l2size);
319 
320 	/* Allow user to override all this if necessary. */
321 	if (cachesize_override != -1)
322 		l2size = cachesize_override;
323 
324 	if (l2size == 0)
325 		return;		/* Again, no L2 cache is possible */
326 #endif
327 
328 	c->x86_cache_size = l2size;
329 
330 	printk(KERN_INFO "CPU: L2 Cache: %dK (%d bytes/line)\n",
331 			l2size, ecx & 0xFF);
332 }
333 
334 void __cpuinit detect_ht(struct cpuinfo_x86 *c)
335 {
336 #ifdef CONFIG_X86_HT
337 	u32 eax, ebx, ecx, edx;
338 	int index_msb, core_bits;
339 
340 	if (!cpu_has(c, X86_FEATURE_HT))
341 		return;
342 
343 	if (cpu_has(c, X86_FEATURE_CMP_LEGACY))
344 		goto out;
345 
346 	if (cpu_has(c, X86_FEATURE_XTOPOLOGY))
347 		return;
348 
349 	cpuid(1, &eax, &ebx, &ecx, &edx);
350 
351 	smp_num_siblings = (ebx & 0xff0000) >> 16;
352 
353 	if (smp_num_siblings == 1) {
354 		printk(KERN_INFO  "CPU: Hyper-Threading is disabled\n");
355 	} else if (smp_num_siblings > 1) {
356 
357 		if (smp_num_siblings > NR_CPUS) {
358 			printk(KERN_WARNING "CPU: Unsupported number of siblings %d",
359 					smp_num_siblings);
360 			smp_num_siblings = 1;
361 			return;
362 		}
363 
364 		index_msb = get_count_order(smp_num_siblings);
365 #ifdef CONFIG_X86_64
366 		c->phys_proc_id = phys_pkg_id(index_msb);
367 #else
368 		c->phys_proc_id = phys_pkg_id(c->initial_apicid, index_msb);
369 #endif
370 
371 		smp_num_siblings = smp_num_siblings / c->x86_max_cores;
372 
373 		index_msb = get_count_order(smp_num_siblings);
374 
375 		core_bits = get_count_order(c->x86_max_cores);
376 
377 #ifdef CONFIG_X86_64
378 		c->cpu_core_id = phys_pkg_id(index_msb) &
379 					       ((1 << core_bits) - 1);
380 #else
381 		c->cpu_core_id = phys_pkg_id(c->initial_apicid, index_msb) &
382 					       ((1 << core_bits) - 1);
383 #endif
384 	}
385 
386 out:
387 	if ((c->x86_max_cores * smp_num_siblings) > 1) {
388 		printk(KERN_INFO  "CPU: Physical Processor ID: %d\n",
389 		       c->phys_proc_id);
390 		printk(KERN_INFO  "CPU: Processor Core ID: %d\n",
391 		       c->cpu_core_id);
392 	}
393 #endif
394 }
395 
396 static void __cpuinit get_cpu_vendor(struct cpuinfo_x86 *c)
397 {
398 	char *v = c->x86_vendor_id;
399 	int i;
400 	static int printed;
401 
402 	for (i = 0; i < X86_VENDOR_NUM; i++) {
403 		if (!cpu_devs[i])
404 			break;
405 
406 		if (!strcmp(v, cpu_devs[i]->c_ident[0]) ||
407 		    (cpu_devs[i]->c_ident[1] &&
408 		     !strcmp(v, cpu_devs[i]->c_ident[1]))) {
409 			this_cpu = cpu_devs[i];
410 			c->x86_vendor = this_cpu->c_x86_vendor;
411 			return;
412 		}
413 	}
414 
415 	if (!printed) {
416 		printed++;
417 		printk(KERN_ERR "CPU: vendor_id '%s' unknown, using generic init.\n", v);
418 		printk(KERN_ERR "CPU: Your system may be unstable.\n");
419 	}
420 
421 	c->x86_vendor = X86_VENDOR_UNKNOWN;
422 	this_cpu = &default_cpu;
423 }
424 
425 void __cpuinit cpu_detect(struct cpuinfo_x86 *c)
426 {
427 	/* Get vendor name */
428 	cpuid(0x00000000, (unsigned int *)&c->cpuid_level,
429 	      (unsigned int *)&c->x86_vendor_id[0],
430 	      (unsigned int *)&c->x86_vendor_id[8],
431 	      (unsigned int *)&c->x86_vendor_id[4]);
432 
433 	c->x86 = 4;
434 	/* Intel-defined flags: level 0x00000001 */
435 	if (c->cpuid_level >= 0x00000001) {
436 		u32 junk, tfms, cap0, misc;
437 		cpuid(0x00000001, &tfms, &misc, &junk, &cap0);
438 		c->x86 = (tfms >> 8) & 0xf;
439 		c->x86_model = (tfms >> 4) & 0xf;
440 		c->x86_mask = tfms & 0xf;
441 		if (c->x86 == 0xf)
442 			c->x86 += (tfms >> 20) & 0xff;
443 		if (c->x86 >= 0x6)
444 			c->x86_model += ((tfms >> 16) & 0xf) << 4;
445 		if (cap0 & (1<<19)) {
446 			c->x86_clflush_size = ((misc >> 8) & 0xff) * 8;
447 			c->x86_cache_alignment = c->x86_clflush_size;
448 		}
449 	}
450 }
451 
452 static void __cpuinit get_cpu_cap(struct cpuinfo_x86 *c)
453 {
454 	u32 tfms, xlvl;
455 	u32 ebx;
456 
457 	/* Intel-defined flags: level 0x00000001 */
458 	if (c->cpuid_level >= 0x00000001) {
459 		u32 capability, excap;
460 		cpuid(0x00000001, &tfms, &ebx, &excap, &capability);
461 		c->x86_capability[0] = capability;
462 		c->x86_capability[4] = excap;
463 	}
464 
465 	/* AMD-defined flags: level 0x80000001 */
466 	xlvl = cpuid_eax(0x80000000);
467 	c->extended_cpuid_level = xlvl;
468 	if ((xlvl & 0xffff0000) == 0x80000000) {
469 		if (xlvl >= 0x80000001) {
470 			c->x86_capability[1] = cpuid_edx(0x80000001);
471 			c->x86_capability[6] = cpuid_ecx(0x80000001);
472 		}
473 	}
474 
475 #ifdef CONFIG_X86_64
476 	if (c->extended_cpuid_level >= 0x80000008) {
477 		u32 eax = cpuid_eax(0x80000008);
478 
479 		c->x86_virt_bits = (eax >> 8) & 0xff;
480 		c->x86_phys_bits = eax & 0xff;
481 	}
482 #endif
483 
484 	if (c->extended_cpuid_level >= 0x80000007)
485 		c->x86_power = cpuid_edx(0x80000007);
486 
487 }
488 
489 static void __cpuinit identify_cpu_without_cpuid(struct cpuinfo_x86 *c)
490 {
491 #ifdef CONFIG_X86_32
492 	int i;
493 
494 	/*
495 	 * First of all, decide if this is a 486 or higher
496 	 * It's a 486 if we can modify the AC flag
497 	 */
498 	if (flag_is_changeable_p(X86_EFLAGS_AC))
499 		c->x86 = 4;
500 	else
501 		c->x86 = 3;
502 
503 	for (i = 0; i < X86_VENDOR_NUM; i++)
504 		if (cpu_devs[i] && cpu_devs[i]->c_identify) {
505 			c->x86_vendor_id[0] = 0;
506 			cpu_devs[i]->c_identify(c);
507 			if (c->x86_vendor_id[0]) {
508 				get_cpu_vendor(c);
509 				break;
510 			}
511 		}
512 #endif
513 }
514 
515 /*
516  * Do minimum CPU detection early.
517  * Fields really needed: vendor, cpuid_level, family, model, mask,
518  * cache alignment.
519  * The others are not touched to avoid unwanted side effects.
520  *
521  * WARNING: this function is only called on the BP.  Don't add code here
522  * that is supposed to run on all CPUs.
523  */
524 static void __init early_identify_cpu(struct cpuinfo_x86 *c)
525 {
526 #ifdef CONFIG_X86_64
527 	c->x86_clflush_size = 64;
528 #else
529 	c->x86_clflush_size = 32;
530 #endif
531 	c->x86_cache_alignment = c->x86_clflush_size;
532 
533 	memset(&c->x86_capability, 0, sizeof c->x86_capability);
534 	c->extended_cpuid_level = 0;
535 
536 	if (!have_cpuid_p())
537 		identify_cpu_without_cpuid(c);
538 
539 	/* cyrix could have cpuid enabled via c_identify()*/
540 	if (!have_cpuid_p())
541 		return;
542 
543 	cpu_detect(c);
544 
545 	get_cpu_vendor(c);
546 
547 	get_cpu_cap(c);
548 
549 	if (this_cpu->c_early_init)
550 		this_cpu->c_early_init(c);
551 
552 	validate_pat_support(c);
553 
554 #ifdef CONFIG_SMP
555 	c->cpu_index = boot_cpu_id;
556 #endif
557 }
558 
559 void __init early_cpu_init(void)
560 {
561 	struct cpu_dev **cdev;
562 	int count = 0;
563 
564 	printk("KERNEL supported cpus:\n");
565 	for (cdev = __x86_cpu_dev_start; cdev < __x86_cpu_dev_end; cdev++) {
566 		struct cpu_dev *cpudev = *cdev;
567 		unsigned int j;
568 
569 		if (count >= X86_VENDOR_NUM)
570 			break;
571 		cpu_devs[count] = cpudev;
572 		count++;
573 
574 		for (j = 0; j < 2; j++) {
575 			if (!cpudev->c_ident[j])
576 				continue;
577 			printk("  %s %s\n", cpudev->c_vendor,
578 				cpudev->c_ident[j]);
579 		}
580 	}
581 
582 	early_identify_cpu(&boot_cpu_data);
583 }
584 
585 /*
586  * The NOPL instruction is supposed to exist on all CPUs with
587  * family >= 6; unfortunately, that's not true in practice because
588  * of early VIA chips and (more importantly) broken virtualizers that
589  * are not easy to detect.  In the latter case it doesn't even *fail*
590  * reliably, so probing for it doesn't even work.  Disable it completely
591  * unless we can find a reliable way to detect all the broken cases.
592  */
593 static void __cpuinit detect_nopl(struct cpuinfo_x86 *c)
594 {
595 	clear_cpu_cap(c, X86_FEATURE_NOPL);
596 }
597 
598 static void __cpuinit generic_identify(struct cpuinfo_x86 *c)
599 {
600 	c->extended_cpuid_level = 0;
601 
602 	if (!have_cpuid_p())
603 		identify_cpu_without_cpuid(c);
604 
605 	/* cyrix could have cpuid enabled via c_identify()*/
606 	if (!have_cpuid_p())
607 		return;
608 
609 	cpu_detect(c);
610 
611 	get_cpu_vendor(c);
612 
613 	get_cpu_cap(c);
614 
615 	if (c->cpuid_level >= 0x00000001) {
616 		c->initial_apicid = (cpuid_ebx(1) >> 24) & 0xFF;
617 #ifdef CONFIG_X86_32
618 # ifdef CONFIG_X86_HT
619 		c->apicid = phys_pkg_id(c->initial_apicid, 0);
620 # else
621 		c->apicid = c->initial_apicid;
622 # endif
623 #endif
624 
625 #ifdef CONFIG_X86_HT
626 		c->phys_proc_id = c->initial_apicid;
627 #endif
628 	}
629 
630 	get_model_name(c); /* Default name */
631 
632 	init_scattered_cpuid_features(c);
633 	detect_nopl(c);
634 }
635 
636 /*
637  * This does the hard work of actually picking apart the CPU stuff...
638  */
639 static void __cpuinit identify_cpu(struct cpuinfo_x86 *c)
640 {
641 	int i;
642 
643 	c->loops_per_jiffy = loops_per_jiffy;
644 	c->x86_cache_size = -1;
645 	c->x86_vendor = X86_VENDOR_UNKNOWN;
646 	c->x86_model = c->x86_mask = 0;	/* So far unknown... */
647 	c->x86_vendor_id[0] = '\0'; /* Unset */
648 	c->x86_model_id[0] = '\0';  /* Unset */
649 	c->x86_max_cores = 1;
650 	c->x86_coreid_bits = 0;
651 #ifdef CONFIG_X86_64
652 	c->x86_clflush_size = 64;
653 #else
654 	c->cpuid_level = -1;	/* CPUID not detected */
655 	c->x86_clflush_size = 32;
656 #endif
657 	c->x86_cache_alignment = c->x86_clflush_size;
658 	memset(&c->x86_capability, 0, sizeof c->x86_capability);
659 
660 	generic_identify(c);
661 
662 	if (this_cpu->c_identify)
663 		this_cpu->c_identify(c);
664 
665 #ifdef CONFIG_X86_64
666 	c->apicid = phys_pkg_id(0);
667 #endif
668 
669 	/*
670 	 * Vendor-specific initialization.  In this section we
671 	 * canonicalize the feature flags, meaning if there are
672 	 * features a certain CPU supports which CPUID doesn't
673 	 * tell us, CPUID claiming incorrect flags, or other bugs,
674 	 * we handle them here.
675 	 *
676 	 * At the end of this section, c->x86_capability better
677 	 * indicate the features this CPU genuinely supports!
678 	 */
679 	if (this_cpu->c_init)
680 		this_cpu->c_init(c);
681 
682 	/* Disable the PN if appropriate */
683 	squash_the_stupid_serial_number(c);
684 
685 	/*
686 	 * The vendor-specific functions might have changed features.  Now
687 	 * we do "generic changes."
688 	 */
689 
690 	/* If the model name is still unset, do table lookup. */
691 	if (!c->x86_model_id[0]) {
692 		char *p;
693 		p = table_lookup_model(c);
694 		if (p)
695 			strcpy(c->x86_model_id, p);
696 		else
697 			/* Last resort... */
698 			sprintf(c->x86_model_id, "%02x/%02x",
699 				c->x86, c->x86_model);
700 	}
701 
702 #ifdef CONFIG_X86_64
703 	detect_ht(c);
704 #endif
705 
706 	/*
707 	 * On SMP, boot_cpu_data holds the common feature set between
708 	 * all CPUs; so make sure that we indicate which features are
709 	 * common between the CPUs.  The first time this routine gets
710 	 * executed, c == &boot_cpu_data.
711 	 */
712 	if (c != &boot_cpu_data) {
713 		/* AND the already accumulated flags with these */
714 		for (i = 0; i < NCAPINTS; i++)
715 			boot_cpu_data.x86_capability[i] &= c->x86_capability[i];
716 	}
717 
718 	/* Clear all flags overriden by options */
719 	for (i = 0; i < NCAPINTS; i++)
720 		c->x86_capability[i] &= ~cleared_cpu_caps[i];
721 
722 #ifdef CONFIG_X86_MCE
723 	/* Init Machine Check Exception if available. */
724 	mcheck_init(c);
725 #endif
726 
727 	select_idle_routine(c);
728 
729 #if defined(CONFIG_NUMA) && defined(CONFIG_X86_64)
730 	numa_add_cpu(smp_processor_id());
731 #endif
732 }
733 
734 #ifdef CONFIG_X86_64
735 static void vgetcpu_set_mode(void)
736 {
737 	if (cpu_has(&boot_cpu_data, X86_FEATURE_RDTSCP))
738 		vgetcpu_mode = VGETCPU_RDTSCP;
739 	else
740 		vgetcpu_mode = VGETCPU_LSL;
741 }
742 #endif
743 
744 void __init identify_boot_cpu(void)
745 {
746 	identify_cpu(&boot_cpu_data);
747 #ifdef CONFIG_X86_32
748 	sysenter_setup();
749 	enable_sep_cpu();
750 #else
751 	vgetcpu_set_mode();
752 #endif
753 }
754 
755 void __cpuinit identify_secondary_cpu(struct cpuinfo_x86 *c)
756 {
757 	BUG_ON(c == &boot_cpu_data);
758 	identify_cpu(c);
759 #ifdef CONFIG_X86_32
760 	enable_sep_cpu();
761 #endif
762 	mtrr_ap_init();
763 }
764 
765 struct msr_range {
766 	unsigned min;
767 	unsigned max;
768 };
769 
770 static struct msr_range msr_range_array[] __cpuinitdata = {
771 	{ 0x00000000, 0x00000418},
772 	{ 0xc0000000, 0xc000040b},
773 	{ 0xc0010000, 0xc0010142},
774 	{ 0xc0011000, 0xc001103b},
775 };
776 
777 static void __cpuinit print_cpu_msr(void)
778 {
779 	unsigned index;
780 	u64 val;
781 	int i;
782 	unsigned index_min, index_max;
783 
784 	for (i = 0; i < ARRAY_SIZE(msr_range_array); i++) {
785 		index_min = msr_range_array[i].min;
786 		index_max = msr_range_array[i].max;
787 		for (index = index_min; index < index_max; index++) {
788 			if (rdmsrl_amd_safe(index, &val))
789 				continue;
790 			printk(KERN_INFO " MSR%08x: %016llx\n", index, val);
791 		}
792 	}
793 }
794 
795 static int show_msr __cpuinitdata;
796 static __init int setup_show_msr(char *arg)
797 {
798 	int num;
799 
800 	get_option(&arg, &num);
801 
802 	if (num > 0)
803 		show_msr = num;
804 	return 1;
805 }
806 __setup("show_msr=", setup_show_msr);
807 
808 static __init int setup_noclflush(char *arg)
809 {
810 	setup_clear_cpu_cap(X86_FEATURE_CLFLSH);
811 	return 1;
812 }
813 __setup("noclflush", setup_noclflush);
814 
815 void __cpuinit print_cpu_info(struct cpuinfo_x86 *c)
816 {
817 	char *vendor = NULL;
818 
819 	if (c->x86_vendor < X86_VENDOR_NUM)
820 		vendor = this_cpu->c_vendor;
821 	else if (c->cpuid_level >= 0)
822 		vendor = c->x86_vendor_id;
823 
824 	if (vendor && !strstr(c->x86_model_id, vendor))
825 		printk(KERN_CONT "%s ", vendor);
826 
827 	if (c->x86_model_id[0])
828 		printk(KERN_CONT "%s", c->x86_model_id);
829 	else
830 		printk(KERN_CONT "%d86", c->x86);
831 
832 	if (c->x86_mask || c->cpuid_level >= 0)
833 		printk(KERN_CONT " stepping %02x\n", c->x86_mask);
834 	else
835 		printk(KERN_CONT "\n");
836 
837 #ifdef CONFIG_SMP
838 	if (c->cpu_index < show_msr)
839 		print_cpu_msr();
840 #else
841 	if (show_msr)
842 		print_cpu_msr();
843 #endif
844 }
845 
846 static __init int setup_disablecpuid(char *arg)
847 {
848 	int bit;
849 	if (get_option(&arg, &bit) && bit < NCAPINTS*32)
850 		setup_clear_cpu_cap(bit);
851 	else
852 		return 0;
853 	return 1;
854 }
855 __setup("clearcpuid=", setup_disablecpuid);
856 
857 cpumask_t cpu_initialized __cpuinitdata = CPU_MASK_NONE;
858 
859 #ifdef CONFIG_X86_64
860 struct x8664_pda **_cpu_pda __read_mostly;
861 EXPORT_SYMBOL(_cpu_pda);
862 
863 struct desc_ptr idt_descr = { 256 * 16 - 1, (unsigned long) idt_table };
864 
865 char boot_cpu_stack[IRQSTACKSIZE] __page_aligned_bss;
866 
867 void __cpuinit pda_init(int cpu)
868 {
869 	struct x8664_pda *pda = cpu_pda(cpu);
870 
871 	/* Setup up data that may be needed in __get_free_pages early */
872 	loadsegment(fs, 0);
873 	loadsegment(gs, 0);
874 	/* Memory clobbers used to order PDA accessed */
875 	mb();
876 	wrmsrl(MSR_GS_BASE, pda);
877 	mb();
878 
879 	pda->cpunumber = cpu;
880 	pda->irqcount = -1;
881 	pda->kernelstack = (unsigned long)stack_thread_info() -
882 				 PDA_STACKOFFSET + THREAD_SIZE;
883 	pda->active_mm = &init_mm;
884 	pda->mmu_state = 0;
885 
886 	if (cpu == 0) {
887 		/* others are initialized in smpboot.c */
888 		pda->pcurrent = &init_task;
889 		pda->irqstackptr = boot_cpu_stack;
890 		pda->irqstackptr += IRQSTACKSIZE - 64;
891 	} else {
892 		if (!pda->irqstackptr) {
893 			pda->irqstackptr = (char *)
894 				__get_free_pages(GFP_ATOMIC, IRQSTACK_ORDER);
895 			if (!pda->irqstackptr)
896 				panic("cannot allocate irqstack for cpu %d",
897 				      cpu);
898 			pda->irqstackptr += IRQSTACKSIZE - 64;
899 		}
900 
901 		if (pda->nodenumber == 0 && cpu_to_node(cpu) != NUMA_NO_NODE)
902 			pda->nodenumber = cpu_to_node(cpu);
903 	}
904 }
905 
906 char boot_exception_stacks[(N_EXCEPTION_STACKS - 1) * EXCEPTION_STKSZ +
907 			   DEBUG_STKSZ] __page_aligned_bss;
908 
909 extern asmlinkage void ignore_sysret(void);
910 
911 /* May not be marked __init: used by software suspend */
912 void syscall_init(void)
913 {
914 	/*
915 	 * LSTAR and STAR live in a bit strange symbiosis.
916 	 * They both write to the same internal register. STAR allows to
917 	 * set CS/DS but only a 32bit target. LSTAR sets the 64bit rip.
918 	 */
919 	wrmsrl(MSR_STAR,  ((u64)__USER32_CS)<<48  | ((u64)__KERNEL_CS)<<32);
920 	wrmsrl(MSR_LSTAR, system_call);
921 	wrmsrl(MSR_CSTAR, ignore_sysret);
922 
923 #ifdef CONFIG_IA32_EMULATION
924 	syscall32_cpu_init();
925 #endif
926 
927 	/* Flags to clear on syscall */
928 	wrmsrl(MSR_SYSCALL_MASK,
929 	       X86_EFLAGS_TF|X86_EFLAGS_DF|X86_EFLAGS_IF|X86_EFLAGS_IOPL);
930 }
931 
932 unsigned long kernel_eflags;
933 
934 /*
935  * Copies of the original ist values from the tss are only accessed during
936  * debugging, no special alignment required.
937  */
938 DEFINE_PER_CPU(struct orig_ist, orig_ist);
939 
940 #else
941 
942 /* Make sure %fs is initialized properly in idle threads */
943 struct pt_regs * __cpuinit idle_regs(struct pt_regs *regs)
944 {
945 	memset(regs, 0, sizeof(struct pt_regs));
946 	regs->fs = __KERNEL_PERCPU;
947 	return regs;
948 }
949 #endif
950 
951 /*
952  * cpu_init() initializes state that is per-CPU. Some data is already
953  * initialized (naturally) in the bootstrap process, such as the GDT
954  * and IDT. We reload them nevertheless, this function acts as a
955  * 'CPU state barrier', nothing should get across.
956  * A lot of state is already set up in PDA init for 64 bit
957  */
958 #ifdef CONFIG_X86_64
959 void __cpuinit cpu_init(void)
960 {
961 	int cpu = stack_smp_processor_id();
962 	struct tss_struct *t = &per_cpu(init_tss, cpu);
963 	struct orig_ist *orig_ist = &per_cpu(orig_ist, cpu);
964 	unsigned long v;
965 	char *estacks = NULL;
966 	struct task_struct *me;
967 	int i;
968 
969 	/* CPU 0 is initialised in head64.c */
970 	if (cpu != 0)
971 		pda_init(cpu);
972 	else
973 		estacks = boot_exception_stacks;
974 
975 	me = current;
976 
977 	if (cpu_test_and_set(cpu, cpu_initialized))
978 		panic("CPU#%d already initialized!\n", cpu);
979 
980 	printk(KERN_INFO "Initializing CPU#%d\n", cpu);
981 
982 	clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
983 
984 	/*
985 	 * Initialize the per-CPU GDT with the boot GDT,
986 	 * and set up the GDT descriptor:
987 	 */
988 
989 	switch_to_new_gdt();
990 	load_idt((const struct desc_ptr *)&idt_descr);
991 
992 	memset(me->thread.tls_array, 0, GDT_ENTRY_TLS_ENTRIES * 8);
993 	syscall_init();
994 
995 	wrmsrl(MSR_FS_BASE, 0);
996 	wrmsrl(MSR_KERNEL_GS_BASE, 0);
997 	barrier();
998 
999 	check_efer();
1000 	if (cpu != 0 && x2apic)
1001 		enable_x2apic();
1002 
1003 	/*
1004 	 * set up and load the per-CPU TSS
1005 	 */
1006 	if (!orig_ist->ist[0]) {
1007 		static const unsigned int order[N_EXCEPTION_STACKS] = {
1008 		  [0 ... N_EXCEPTION_STACKS - 1] = EXCEPTION_STACK_ORDER,
1009 		  [DEBUG_STACK - 1] = DEBUG_STACK_ORDER
1010 		};
1011 		for (v = 0; v < N_EXCEPTION_STACKS; v++) {
1012 			if (cpu) {
1013 				estacks = (char *)__get_free_pages(GFP_ATOMIC, order[v]);
1014 				if (!estacks)
1015 					panic("Cannot allocate exception "
1016 					      "stack %ld %d\n", v, cpu);
1017 			}
1018 			estacks += PAGE_SIZE << order[v];
1019 			orig_ist->ist[v] = t->x86_tss.ist[v] =
1020 					(unsigned long)estacks;
1021 		}
1022 	}
1023 
1024 	t->x86_tss.io_bitmap_base = offsetof(struct tss_struct, io_bitmap);
1025 	/*
1026 	 * <= is required because the CPU will access up to
1027 	 * 8 bits beyond the end of the IO permission bitmap.
1028 	 */
1029 	for (i = 0; i <= IO_BITMAP_LONGS; i++)
1030 		t->io_bitmap[i] = ~0UL;
1031 
1032 	atomic_inc(&init_mm.mm_count);
1033 	me->active_mm = &init_mm;
1034 	if (me->mm)
1035 		BUG();
1036 	enter_lazy_tlb(&init_mm, me);
1037 
1038 	load_sp0(t, &current->thread);
1039 	set_tss_desc(cpu, t);
1040 	load_TR_desc();
1041 	load_LDT(&init_mm.context);
1042 
1043 #ifdef CONFIG_KGDB
1044 	/*
1045 	 * If the kgdb is connected no debug regs should be altered.  This
1046 	 * is only applicable when KGDB and a KGDB I/O module are built
1047 	 * into the kernel and you are using early debugging with
1048 	 * kgdbwait. KGDB will control the kernel HW breakpoint registers.
1049 	 */
1050 	if (kgdb_connected && arch_kgdb_ops.correct_hw_break)
1051 		arch_kgdb_ops.correct_hw_break();
1052 	else {
1053 #endif
1054 	/*
1055 	 * Clear all 6 debug registers:
1056 	 */
1057 
1058 	set_debugreg(0UL, 0);
1059 	set_debugreg(0UL, 1);
1060 	set_debugreg(0UL, 2);
1061 	set_debugreg(0UL, 3);
1062 	set_debugreg(0UL, 6);
1063 	set_debugreg(0UL, 7);
1064 #ifdef CONFIG_KGDB
1065 	/* If the kgdb is connected no debug regs should be altered. */
1066 	}
1067 #endif
1068 
1069 	fpu_init();
1070 
1071 	raw_local_save_flags(kernel_eflags);
1072 
1073 	if (is_uv_system())
1074 		uv_cpu_init();
1075 }
1076 
1077 #else
1078 
1079 void __cpuinit cpu_init(void)
1080 {
1081 	int cpu = smp_processor_id();
1082 	struct task_struct *curr = current;
1083 	struct tss_struct *t = &per_cpu(init_tss, cpu);
1084 	struct thread_struct *thread = &curr->thread;
1085 
1086 	if (cpu_test_and_set(cpu, cpu_initialized)) {
1087 		printk(KERN_WARNING "CPU#%d already initialized!\n", cpu);
1088 		for (;;) local_irq_enable();
1089 	}
1090 
1091 	printk(KERN_INFO "Initializing CPU#%d\n", cpu);
1092 
1093 	if (cpu_has_vme || cpu_has_tsc || cpu_has_de)
1094 		clear_in_cr4(X86_CR4_VME|X86_CR4_PVI|X86_CR4_TSD|X86_CR4_DE);
1095 
1096 	load_idt(&idt_descr);
1097 	switch_to_new_gdt();
1098 
1099 	/*
1100 	 * Set up and load the per-CPU TSS and LDT
1101 	 */
1102 	atomic_inc(&init_mm.mm_count);
1103 	curr->active_mm = &init_mm;
1104 	if (curr->mm)
1105 		BUG();
1106 	enter_lazy_tlb(&init_mm, curr);
1107 
1108 	load_sp0(t, thread);
1109 	set_tss_desc(cpu, t);
1110 	load_TR_desc();
1111 	load_LDT(&init_mm.context);
1112 
1113 #ifdef CONFIG_DOUBLEFAULT
1114 	/* Set up doublefault TSS pointer in the GDT */
1115 	__set_tss_desc(cpu, GDT_ENTRY_DOUBLEFAULT_TSS, &doublefault_tss);
1116 #endif
1117 
1118 	/* Clear %gs. */
1119 	asm volatile ("mov %0, %%gs" : : "r" (0));
1120 
1121 	/* Clear all 6 debug registers: */
1122 	set_debugreg(0, 0);
1123 	set_debugreg(0, 1);
1124 	set_debugreg(0, 2);
1125 	set_debugreg(0, 3);
1126 	set_debugreg(0, 6);
1127 	set_debugreg(0, 7);
1128 
1129 	/*
1130 	 * Force FPU initialization:
1131 	 */
1132 	if (cpu_has_xsave)
1133 		current_thread_info()->status = TS_XSAVE;
1134 	else
1135 		current_thread_info()->status = 0;
1136 	clear_used_math();
1137 	mxcsr_feature_mask_init();
1138 
1139 	/*
1140 	 * Boot processor to setup the FP and extended state context info.
1141 	 */
1142 	if (smp_processor_id() == boot_cpu_id)
1143 		init_thread_xstate();
1144 
1145 	xsave_init();
1146 }
1147 
1148 
1149 #endif
1150