xref: /openbmc/linux/arch/x86/kernel/cpu/microcode/intel.c (revision 8730046c)
1 /*
2  * Intel CPU Microcode Update Driver for Linux
3  *
4  * Copyright (C) 2000-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
5  *		 2006 Shaohua Li <shaohua.li@intel.com>
6  *
7  * Intel CPU microcode early update for Linux
8  *
9  * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
10  *		      H Peter Anvin" <hpa@zytor.com>
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License
14  * as published by the Free Software Foundation; either version
15  * 2 of the License, or (at your option) any later version.
16  */
17 
18 /*
19  * This needs to be before all headers so that pr_debug in printk.h doesn't turn
20  * printk calls into no_printk().
21  *
22  *#define DEBUG
23  */
24 #define pr_fmt(fmt) "microcode: " fmt
25 
26 #include <linux/earlycpio.h>
27 #include <linux/firmware.h>
28 #include <linux/uaccess.h>
29 #include <linux/vmalloc.h>
30 #include <linux/initrd.h>
31 #include <linux/kernel.h>
32 #include <linux/slab.h>
33 #include <linux/cpu.h>
34 #include <linux/mm.h>
35 
36 #include <asm/microcode_intel.h>
37 #include <asm/processor.h>
38 #include <asm/tlbflush.h>
39 #include <asm/setup.h>
40 #include <asm/msr.h>
41 
42 static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
43 
44 /* Current microcode patch used in early patching */
45 struct microcode_intel *intel_ucode_patch;
46 
47 static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
48 					unsigned int s2, unsigned int p2)
49 {
50 	if (s1 != s2)
51 		return false;
52 
53 	/* Processor flags are either both 0 ... */
54 	if (!p1 && !p2)
55 		return true;
56 
57 	/* ... or they intersect. */
58 	return p1 & p2;
59 }
60 
61 /*
62  * Returns 1 if update has been found, 0 otherwise.
63  */
64 static int find_matching_signature(void *mc, unsigned int csig, int cpf)
65 {
66 	struct microcode_header_intel *mc_hdr = mc;
67 	struct extended_sigtable *ext_hdr;
68 	struct extended_signature *ext_sig;
69 	int i;
70 
71 	if (cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
72 		return 1;
73 
74 	/* Look for ext. headers: */
75 	if (get_totalsize(mc_hdr) <= get_datasize(mc_hdr) + MC_HEADER_SIZE)
76 		return 0;
77 
78 	ext_hdr = mc + get_datasize(mc_hdr) + MC_HEADER_SIZE;
79 	ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
80 
81 	for (i = 0; i < ext_hdr->count; i++) {
82 		if (cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
83 			return 1;
84 		ext_sig++;
85 	}
86 	return 0;
87 }
88 
89 /*
90  * Returns 1 if update has been found, 0 otherwise.
91  */
92 static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
93 {
94 	struct microcode_header_intel *mc_hdr = mc;
95 
96 	if (mc_hdr->rev <= new_rev)
97 		return 0;
98 
99 	return find_matching_signature(mc, csig, cpf);
100 }
101 
102 /*
103  * Given CPU signature and a microcode patch, this function finds if the
104  * microcode patch has matching family and model with the CPU.
105  *
106  * %true - if there's a match
107  * %false - otherwise
108  */
109 static bool microcode_matches(struct microcode_header_intel *mc_header,
110 			      unsigned long sig)
111 {
112 	unsigned long total_size = get_totalsize(mc_header);
113 	unsigned long data_size = get_datasize(mc_header);
114 	struct extended_sigtable *ext_header;
115 	unsigned int fam_ucode, model_ucode;
116 	struct extended_signature *ext_sig;
117 	unsigned int fam, model;
118 	int ext_sigcount, i;
119 
120 	fam   = x86_family(sig);
121 	model = x86_model(sig);
122 
123 	fam_ucode   = x86_family(mc_header->sig);
124 	model_ucode = x86_model(mc_header->sig);
125 
126 	if (fam == fam_ucode && model == model_ucode)
127 		return true;
128 
129 	/* Look for ext. headers: */
130 	if (total_size <= data_size + MC_HEADER_SIZE)
131 		return false;
132 
133 	ext_header   = (void *) mc_header + data_size + MC_HEADER_SIZE;
134 	ext_sig      = (void *)ext_header + EXT_HEADER_SIZE;
135 	ext_sigcount = ext_header->count;
136 
137 	for (i = 0; i < ext_sigcount; i++) {
138 		fam_ucode   = x86_family(ext_sig->sig);
139 		model_ucode = x86_model(ext_sig->sig);
140 
141 		if (fam == fam_ucode && model == model_ucode)
142 			return true;
143 
144 		ext_sig++;
145 	}
146 	return false;
147 }
148 
149 static struct ucode_patch *__alloc_microcode_buf(void *data, unsigned int size)
150 {
151 	struct ucode_patch *p;
152 
153 	p = kzalloc(sizeof(struct ucode_patch), GFP_KERNEL);
154 	if (!p)
155 		return ERR_PTR(-ENOMEM);
156 
157 	p->data = kmemdup(data, size, GFP_KERNEL);
158 	if (!p->data) {
159 		kfree(p);
160 		return ERR_PTR(-ENOMEM);
161 	}
162 
163 	return p;
164 }
165 
166 static void save_microcode_patch(void *data, unsigned int size)
167 {
168 	struct microcode_header_intel *mc_hdr, *mc_saved_hdr;
169 	struct ucode_patch *iter, *tmp, *p;
170 	bool prev_found = false;
171 	unsigned int sig, pf;
172 
173 	mc_hdr = (struct microcode_header_intel *)data;
174 
175 	list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
176 		mc_saved_hdr = (struct microcode_header_intel *)iter->data;
177 		sig	     = mc_saved_hdr->sig;
178 		pf	     = mc_saved_hdr->pf;
179 
180 		if (find_matching_signature(data, sig, pf)) {
181 			prev_found = true;
182 
183 			if (mc_hdr->rev <= mc_saved_hdr->rev)
184 				continue;
185 
186 			p = __alloc_microcode_buf(data, size);
187 			if (IS_ERR(p))
188 				pr_err("Error allocating buffer %p\n", data);
189 			else
190 				list_replace(&iter->plist, &p->plist);
191 		}
192 	}
193 
194 	/*
195 	 * There weren't any previous patches found in the list cache; save the
196 	 * newly found.
197 	 */
198 	if (!prev_found) {
199 		p = __alloc_microcode_buf(data, size);
200 		if (IS_ERR(p))
201 			pr_err("Error allocating buffer for %p\n", data);
202 		else
203 			list_add_tail(&p->plist, &microcode_cache);
204 	}
205 }
206 
207 static int microcode_sanity_check(void *mc, int print_err)
208 {
209 	unsigned long total_size, data_size, ext_table_size;
210 	struct microcode_header_intel *mc_header = mc;
211 	struct extended_sigtable *ext_header = NULL;
212 	u32 sum, orig_sum, ext_sigcount = 0, i;
213 	struct extended_signature *ext_sig;
214 
215 	total_size = get_totalsize(mc_header);
216 	data_size = get_datasize(mc_header);
217 
218 	if (data_size + MC_HEADER_SIZE > total_size) {
219 		if (print_err)
220 			pr_err("Error: bad microcode data file size.\n");
221 		return -EINVAL;
222 	}
223 
224 	if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
225 		if (print_err)
226 			pr_err("Error: invalid/unknown microcode update format.\n");
227 		return -EINVAL;
228 	}
229 
230 	ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
231 	if (ext_table_size) {
232 		u32 ext_table_sum = 0;
233 		u32 *ext_tablep;
234 
235 		if ((ext_table_size < EXT_HEADER_SIZE)
236 		 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
237 			if (print_err)
238 				pr_err("Error: truncated extended signature table.\n");
239 			return -EINVAL;
240 		}
241 
242 		ext_header = mc + MC_HEADER_SIZE + data_size;
243 		if (ext_table_size != exttable_size(ext_header)) {
244 			if (print_err)
245 				pr_err("Error: extended signature table size mismatch.\n");
246 			return -EFAULT;
247 		}
248 
249 		ext_sigcount = ext_header->count;
250 
251 		/*
252 		 * Check extended table checksum: the sum of all dwords that
253 		 * comprise a valid table must be 0.
254 		 */
255 		ext_tablep = (u32 *)ext_header;
256 
257 		i = ext_table_size / sizeof(u32);
258 		while (i--)
259 			ext_table_sum += ext_tablep[i];
260 
261 		if (ext_table_sum) {
262 			if (print_err)
263 				pr_warn("Bad extended signature table checksum, aborting.\n");
264 			return -EINVAL;
265 		}
266 	}
267 
268 	/*
269 	 * Calculate the checksum of update data and header. The checksum of
270 	 * valid update data and header including the extended signature table
271 	 * must be 0.
272 	 */
273 	orig_sum = 0;
274 	i = (MC_HEADER_SIZE + data_size) / sizeof(u32);
275 	while (i--)
276 		orig_sum += ((u32 *)mc)[i];
277 
278 	if (orig_sum) {
279 		if (print_err)
280 			pr_err("Bad microcode data checksum, aborting.\n");
281 		return -EINVAL;
282 	}
283 
284 	if (!ext_table_size)
285 		return 0;
286 
287 	/*
288 	 * Check extended signature checksum: 0 => valid.
289 	 */
290 	for (i = 0; i < ext_sigcount; i++) {
291 		ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
292 			  EXT_SIGNATURE_SIZE * i;
293 
294 		sum = (mc_header->sig + mc_header->pf + mc_header->cksum) -
295 		      (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
296 		if (sum) {
297 			if (print_err)
298 				pr_err("Bad extended signature checksum, aborting.\n");
299 			return -EINVAL;
300 		}
301 	}
302 	return 0;
303 }
304 
305 /*
306  * Get microcode matching with BSP's model. Only CPUs with the same model as
307  * BSP can stay in the platform.
308  */
309 static struct microcode_intel *
310 scan_microcode(void *data, size_t size, struct ucode_cpu_info *uci, bool save)
311 {
312 	struct microcode_header_intel *mc_header;
313 	struct microcode_intel *patch = NULL;
314 	unsigned int mc_size;
315 
316 	while (size) {
317 		if (size < sizeof(struct microcode_header_intel))
318 			break;
319 
320 		mc_header = (struct microcode_header_intel *)data;
321 
322 		mc_size = get_totalsize(mc_header);
323 		if (!mc_size ||
324 		    mc_size > size ||
325 		    microcode_sanity_check(data, 0) < 0)
326 			break;
327 
328 		size -= mc_size;
329 
330 		if (!microcode_matches(mc_header, uci->cpu_sig.sig)) {
331 			data += mc_size;
332 			continue;
333 		}
334 
335 		if (save) {
336 			save_microcode_patch(data, mc_size);
337 			goto next;
338 		}
339 
340 
341 		if (!patch) {
342 			if (!has_newer_microcode(data,
343 						 uci->cpu_sig.sig,
344 						 uci->cpu_sig.pf,
345 						 uci->cpu_sig.rev))
346 				goto next;
347 
348 		} else {
349 			struct microcode_header_intel *phdr = &patch->hdr;
350 
351 			if (!has_newer_microcode(data,
352 						 phdr->sig,
353 						 phdr->pf,
354 						 phdr->rev))
355 				goto next;
356 		}
357 
358 		/* We have a newer patch, save it. */
359 		patch = data;
360 
361 next:
362 		data += mc_size;
363 	}
364 
365 	if (size)
366 		return NULL;
367 
368 	return patch;
369 }
370 
371 static int collect_cpu_info_early(struct ucode_cpu_info *uci)
372 {
373 	unsigned int val[2];
374 	unsigned int family, model;
375 	struct cpu_signature csig = { 0 };
376 	unsigned int eax, ebx, ecx, edx;
377 
378 	memset(uci, 0, sizeof(*uci));
379 
380 	eax = 0x00000001;
381 	ecx = 0;
382 	native_cpuid(&eax, &ebx, &ecx, &edx);
383 	csig.sig = eax;
384 
385 	family = x86_family(eax);
386 	model  = x86_model(eax);
387 
388 	if ((model >= 5) || (family > 6)) {
389 		/* get processor flags from MSR 0x17 */
390 		native_rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
391 		csig.pf = 1 << ((val[1] >> 18) & 7);
392 	}
393 
394 	csig.rev = intel_get_microcode_revision();
395 
396 	uci->cpu_sig = csig;
397 	uci->valid = 1;
398 
399 	return 0;
400 }
401 
402 static void show_saved_mc(void)
403 {
404 #ifdef DEBUG
405 	int i = 0, j;
406 	unsigned int sig, pf, rev, total_size, data_size, date;
407 	struct ucode_cpu_info uci;
408 	struct ucode_patch *p;
409 
410 	if (list_empty(&microcode_cache)) {
411 		pr_debug("no microcode data saved.\n");
412 		return;
413 	}
414 
415 	collect_cpu_info_early(&uci);
416 
417 	sig	= uci.cpu_sig.sig;
418 	pf	= uci.cpu_sig.pf;
419 	rev	= uci.cpu_sig.rev;
420 	pr_debug("CPU: sig=0x%x, pf=0x%x, rev=0x%x\n", sig, pf, rev);
421 
422 	list_for_each_entry(p, &microcode_cache, plist) {
423 		struct microcode_header_intel *mc_saved_header;
424 		struct extended_sigtable *ext_header;
425 		struct extended_signature *ext_sig;
426 		int ext_sigcount;
427 
428 		mc_saved_header = (struct microcode_header_intel *)p->data;
429 
430 		sig	= mc_saved_header->sig;
431 		pf	= mc_saved_header->pf;
432 		rev	= mc_saved_header->rev;
433 		date	= mc_saved_header->date;
434 
435 		total_size	= get_totalsize(mc_saved_header);
436 		data_size	= get_datasize(mc_saved_header);
437 
438 		pr_debug("mc_saved[%d]: sig=0x%x, pf=0x%x, rev=0x%x, total size=0x%x, date = %04x-%02x-%02x\n",
439 			 i++, sig, pf, rev, total_size,
440 			 date & 0xffff,
441 			 date >> 24,
442 			 (date >> 16) & 0xff);
443 
444 		/* Look for ext. headers: */
445 		if (total_size <= data_size + MC_HEADER_SIZE)
446 			continue;
447 
448 		ext_header = (void *)mc_saved_header + data_size + MC_HEADER_SIZE;
449 		ext_sigcount = ext_header->count;
450 		ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
451 
452 		for (j = 0; j < ext_sigcount; j++) {
453 			sig = ext_sig->sig;
454 			pf = ext_sig->pf;
455 
456 			pr_debug("\tExtended[%d]: sig=0x%x, pf=0x%x\n",
457 				 j, sig, pf);
458 
459 			ext_sig++;
460 		}
461 	}
462 #endif
463 }
464 
465 /*
466  * Save this microcode patch. It will be loaded early when a CPU is
467  * hot-added or resumes.
468  */
469 static void save_mc_for_early(u8 *mc, unsigned int size)
470 {
471 #ifdef CONFIG_HOTPLUG_CPU
472 	/* Synchronization during CPU hotplug. */
473 	static DEFINE_MUTEX(x86_cpu_microcode_mutex);
474 
475 	mutex_lock(&x86_cpu_microcode_mutex);
476 
477 	save_microcode_patch(mc, size);
478 	show_saved_mc();
479 
480 	mutex_unlock(&x86_cpu_microcode_mutex);
481 #endif
482 }
483 
484 static bool load_builtin_intel_microcode(struct cpio_data *cp)
485 {
486 	unsigned int eax = 1, ebx, ecx = 0, edx;
487 	char name[30];
488 
489 	if (IS_ENABLED(CONFIG_X86_32))
490 		return false;
491 
492 	native_cpuid(&eax, &ebx, &ecx, &edx);
493 
494 	sprintf(name, "intel-ucode/%02x-%02x-%02x",
495 		      x86_family(eax), x86_model(eax), x86_stepping(eax));
496 
497 	return get_builtin_firmware(cp, name);
498 }
499 
500 /*
501  * Print ucode update info.
502  */
503 static void
504 print_ucode_info(struct ucode_cpu_info *uci, unsigned int date)
505 {
506 	pr_info_once("microcode updated early to revision 0x%x, date = %04x-%02x-%02x\n",
507 		     uci->cpu_sig.rev,
508 		     date & 0xffff,
509 		     date >> 24,
510 		     (date >> 16) & 0xff);
511 }
512 
513 #ifdef CONFIG_X86_32
514 
515 static int delay_ucode_info;
516 static int current_mc_date;
517 
518 /*
519  * Print early updated ucode info after printk works. This is delayed info dump.
520  */
521 void show_ucode_info_early(void)
522 {
523 	struct ucode_cpu_info uci;
524 
525 	if (delay_ucode_info) {
526 		collect_cpu_info_early(&uci);
527 		print_ucode_info(&uci, current_mc_date);
528 		delay_ucode_info = 0;
529 	}
530 }
531 
532 /*
533  * At this point, we can not call printk() yet. Delay printing microcode info in
534  * show_ucode_info_early() until printk() works.
535  */
536 static void print_ucode(struct ucode_cpu_info *uci)
537 {
538 	struct microcode_intel *mc;
539 	int *delay_ucode_info_p;
540 	int *current_mc_date_p;
541 
542 	mc = uci->mc;
543 	if (!mc)
544 		return;
545 
546 	delay_ucode_info_p = (int *)__pa_nodebug(&delay_ucode_info);
547 	current_mc_date_p = (int *)__pa_nodebug(&current_mc_date);
548 
549 	*delay_ucode_info_p = 1;
550 	*current_mc_date_p = mc->hdr.date;
551 }
552 #else
553 
554 /*
555  * Flush global tlb. We only do this in x86_64 where paging has been enabled
556  * already and PGE should be enabled as well.
557  */
558 static inline void flush_tlb_early(void)
559 {
560 	__native_flush_tlb_global_irq_disabled();
561 }
562 
563 static inline void print_ucode(struct ucode_cpu_info *uci)
564 {
565 	struct microcode_intel *mc;
566 
567 	mc = uci->mc;
568 	if (!mc)
569 		return;
570 
571 	print_ucode_info(uci, mc->hdr.date);
572 }
573 #endif
574 
575 static int apply_microcode_early(struct ucode_cpu_info *uci, bool early)
576 {
577 	struct microcode_intel *mc;
578 	u32 rev;
579 
580 	mc = uci->mc;
581 	if (!mc)
582 		return 0;
583 
584 	/* write microcode via MSR 0x79 */
585 	native_wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
586 
587 	rev = intel_get_microcode_revision();
588 	if (rev != mc->hdr.rev)
589 		return -1;
590 
591 #ifdef CONFIG_X86_64
592 	/* Flush global tlb. This is precaution. */
593 	flush_tlb_early();
594 #endif
595 	uci->cpu_sig.rev = rev;
596 
597 	if (early)
598 		print_ucode(uci);
599 	else
600 		print_ucode_info(uci, mc->hdr.date);
601 
602 	return 0;
603 }
604 
605 int __init save_microcode_in_initrd_intel(void)
606 {
607 	struct ucode_cpu_info uci;
608 	struct cpio_data cp;
609 
610 	/*
611 	 * AP loading didn't find any microcode patch, no need to save anything.
612 	 */
613 	if (!intel_ucode_patch || IS_ERR(intel_ucode_patch))
614 		return 0;
615 
616 	if (!load_builtin_intel_microcode(&cp))
617 		cp = find_microcode_in_initrd(ucode_path, false);
618 
619 	if (!(cp.data && cp.size))
620 		return 0;
621 
622 	collect_cpu_info_early(&uci);
623 
624 	scan_microcode(cp.data, cp.size, &uci, true);
625 
626 	show_saved_mc();
627 
628 	return 0;
629 }
630 
631 
632 /*
633  * @res_patch, output: a pointer to the patch we found.
634  */
635 static struct microcode_intel *__load_ucode_intel(struct ucode_cpu_info *uci)
636 {
637 	static const char *path;
638 	struct cpio_data cp;
639 	bool use_pa;
640 
641 	if (IS_ENABLED(CONFIG_X86_32)) {
642 		path	  = (const char *)__pa_nodebug(ucode_path);
643 		use_pa	  = true;
644 	} else {
645 		path	  = ucode_path;
646 		use_pa	  = false;
647 	}
648 
649 	/* try built-in microcode first */
650 	if (!load_builtin_intel_microcode(&cp))
651 		cp = find_microcode_in_initrd(path, use_pa);
652 
653 	if (!(cp.data && cp.size))
654 		return NULL;
655 
656 	collect_cpu_info_early(uci);
657 
658 	return scan_microcode(cp.data, cp.size, uci, false);
659 }
660 
661 void __init load_ucode_intel_bsp(void)
662 {
663 	struct microcode_intel *patch;
664 	struct ucode_cpu_info uci;
665 
666 	patch = __load_ucode_intel(&uci);
667 	if (!patch)
668 		return;
669 
670 	uci.mc = patch;
671 
672 	apply_microcode_early(&uci, true);
673 }
674 
675 void load_ucode_intel_ap(void)
676 {
677 	struct microcode_intel *patch, **iup;
678 	struct ucode_cpu_info uci;
679 
680 	if (IS_ENABLED(CONFIG_X86_32))
681 		iup = (struct microcode_intel **) __pa_nodebug(&intel_ucode_patch);
682 	else
683 		iup = &intel_ucode_patch;
684 
685 reget:
686 	if (!*iup) {
687 		patch = __load_ucode_intel(&uci);
688 		if (!patch)
689 			return;
690 
691 		*iup = patch;
692 	}
693 
694 	uci.mc = *iup;
695 
696 	if (apply_microcode_early(&uci, true)) {
697 		/* Mixed-silicon system? Try to refetch the proper patch: */
698 		*iup = NULL;
699 
700 		goto reget;
701 	}
702 }
703 
704 static struct microcode_intel *find_patch(struct ucode_cpu_info *uci)
705 {
706 	struct microcode_header_intel *phdr;
707 	struct ucode_patch *iter, *tmp;
708 
709 	list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
710 
711 		phdr = (struct microcode_header_intel *)iter->data;
712 
713 		if (phdr->rev <= uci->cpu_sig.rev)
714 			continue;
715 
716 		if (!find_matching_signature(phdr,
717 					     uci->cpu_sig.sig,
718 					     uci->cpu_sig.pf))
719 			continue;
720 
721 		return iter->data;
722 	}
723 	return NULL;
724 }
725 
726 void reload_ucode_intel(void)
727 {
728 	struct microcode_intel *p;
729 	struct ucode_cpu_info uci;
730 
731 	collect_cpu_info_early(&uci);
732 
733 	p = find_patch(&uci);
734 	if (!p)
735 		return;
736 
737 	uci.mc = p;
738 
739 	apply_microcode_early(&uci, false);
740 }
741 
742 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
743 {
744 	static struct cpu_signature prev;
745 	struct cpuinfo_x86 *c = &cpu_data(cpu_num);
746 	unsigned int val[2];
747 
748 	memset(csig, 0, sizeof(*csig));
749 
750 	csig->sig = cpuid_eax(0x00000001);
751 
752 	if ((c->x86_model >= 5) || (c->x86 > 6)) {
753 		/* get processor flags from MSR 0x17 */
754 		rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
755 		csig->pf = 1 << ((val[1] >> 18) & 7);
756 	}
757 
758 	csig->rev = c->microcode;
759 
760 	/* No extra locking on prev, races are harmless. */
761 	if (csig->sig != prev.sig || csig->pf != prev.pf || csig->rev != prev.rev) {
762 		pr_info("sig=0x%x, pf=0x%x, revision=0x%x\n",
763 			csig->sig, csig->pf, csig->rev);
764 		prev = *csig;
765 	}
766 
767 	return 0;
768 }
769 
770 static int apply_microcode_intel(int cpu)
771 {
772 	struct microcode_intel *mc;
773 	struct ucode_cpu_info *uci;
774 	struct cpuinfo_x86 *c;
775 	static int prev_rev;
776 	u32 rev;
777 
778 	/* We should bind the task to the CPU */
779 	if (WARN_ON(raw_smp_processor_id() != cpu))
780 		return -1;
781 
782 	uci = ucode_cpu_info + cpu;
783 	mc = uci->mc;
784 	if (!mc) {
785 		/* Look for a newer patch in our cache: */
786 		mc = find_patch(uci);
787 		if (!mc)
788 			return 0;
789 	}
790 
791 	/* write microcode via MSR 0x79 */
792 	wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
793 
794 	rev = intel_get_microcode_revision();
795 
796 	if (rev != mc->hdr.rev) {
797 		pr_err("CPU%d update to revision 0x%x failed\n",
798 		       cpu, mc->hdr.rev);
799 		return -1;
800 	}
801 
802 	if (rev != prev_rev) {
803 		pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n",
804 			rev,
805 			mc->hdr.date & 0xffff,
806 			mc->hdr.date >> 24,
807 			(mc->hdr.date >> 16) & 0xff);
808 		prev_rev = rev;
809 	}
810 
811 	c = &cpu_data(cpu);
812 
813 	uci->cpu_sig.rev = rev;
814 	c->microcode = rev;
815 
816 	return 0;
817 }
818 
819 static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
820 				int (*get_ucode_data)(void *, const void *, size_t))
821 {
822 	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
823 	u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
824 	int new_rev = uci->cpu_sig.rev;
825 	unsigned int leftover = size;
826 	unsigned int curr_mc_size = 0, new_mc_size = 0;
827 	unsigned int csig, cpf;
828 
829 	while (leftover) {
830 		struct microcode_header_intel mc_header;
831 		unsigned int mc_size;
832 
833 		if (leftover < sizeof(mc_header)) {
834 			pr_err("error! Truncated header in microcode data file\n");
835 			break;
836 		}
837 
838 		if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
839 			break;
840 
841 		mc_size = get_totalsize(&mc_header);
842 		if (!mc_size || mc_size > leftover) {
843 			pr_err("error! Bad data in microcode data file\n");
844 			break;
845 		}
846 
847 		/* For performance reasons, reuse mc area when possible */
848 		if (!mc || mc_size > curr_mc_size) {
849 			vfree(mc);
850 			mc = vmalloc(mc_size);
851 			if (!mc)
852 				break;
853 			curr_mc_size = mc_size;
854 		}
855 
856 		if (get_ucode_data(mc, ucode_ptr, mc_size) ||
857 		    microcode_sanity_check(mc, 1) < 0) {
858 			break;
859 		}
860 
861 		csig = uci->cpu_sig.sig;
862 		cpf = uci->cpu_sig.pf;
863 		if (has_newer_microcode(mc, csig, cpf, new_rev)) {
864 			vfree(new_mc);
865 			new_rev = mc_header.rev;
866 			new_mc  = mc;
867 			new_mc_size = mc_size;
868 			mc = NULL;	/* trigger new vmalloc */
869 		}
870 
871 		ucode_ptr += mc_size;
872 		leftover  -= mc_size;
873 	}
874 
875 	vfree(mc);
876 
877 	if (leftover) {
878 		vfree(new_mc);
879 		return UCODE_ERROR;
880 	}
881 
882 	if (!new_mc)
883 		return UCODE_NFOUND;
884 
885 	vfree(uci->mc);
886 	uci->mc = (struct microcode_intel *)new_mc;
887 
888 	/*
889 	 * If early loading microcode is supported, save this mc into
890 	 * permanent memory. So it will be loaded early when a CPU is hot added
891 	 * or resumes.
892 	 */
893 	save_mc_for_early(new_mc, new_mc_size);
894 
895 	pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
896 		 cpu, new_rev, uci->cpu_sig.rev);
897 
898 	return UCODE_OK;
899 }
900 
901 static int get_ucode_fw(void *to, const void *from, size_t n)
902 {
903 	memcpy(to, from, n);
904 	return 0;
905 }
906 
907 static enum ucode_state request_microcode_fw(int cpu, struct device *device,
908 					     bool refresh_fw)
909 {
910 	char name[30];
911 	struct cpuinfo_x86 *c = &cpu_data(cpu);
912 	const struct firmware *firmware;
913 	enum ucode_state ret;
914 
915 	sprintf(name, "intel-ucode/%02x-%02x-%02x",
916 		c->x86, c->x86_model, c->x86_mask);
917 
918 	if (request_firmware_direct(&firmware, name, device)) {
919 		pr_debug("data file %s load failed\n", name);
920 		return UCODE_NFOUND;
921 	}
922 
923 	ret = generic_load_microcode(cpu, (void *)firmware->data,
924 				     firmware->size, &get_ucode_fw);
925 
926 	release_firmware(firmware);
927 
928 	return ret;
929 }
930 
931 static int get_ucode_user(void *to, const void *from, size_t n)
932 {
933 	return copy_from_user(to, from, n);
934 }
935 
936 static enum ucode_state
937 request_microcode_user(int cpu, const void __user *buf, size_t size)
938 {
939 	return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
940 }
941 
942 static struct microcode_ops microcode_intel_ops = {
943 	.request_microcode_user		  = request_microcode_user,
944 	.request_microcode_fw             = request_microcode_fw,
945 	.collect_cpu_info                 = collect_cpu_info,
946 	.apply_microcode                  = apply_microcode_intel,
947 };
948 
949 struct microcode_ops * __init init_intel_microcode(void)
950 {
951 	struct cpuinfo_x86 *c = &boot_cpu_data;
952 
953 	if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
954 	    cpu_has(c, X86_FEATURE_IA64)) {
955 		pr_err("Intel CPU family 0x%x not supported\n", c->x86);
956 		return NULL;
957 	}
958 
959 	return &microcode_intel_ops;
960 }
961