arch/x86/kernel/cpu/microcode/intel.c

   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 on the APs. */
  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         if (!load_builtin_intel_microcode(&cp))
 611                 cp = find_microcode_in_initrd(ucode_path, false);
 612
 613         if (!(cp.data && cp.size))
 614                 return 0;
 615
 616         collect_cpu_info_early(&uci);
 617
 618         scan_microcode(cp.data, cp.size, &uci, true);
 619
 620         show_saved_mc();
 621
 622         return 0;
 623 }
 624
 625 /*
 626  * @res_patch, output: a pointer to the patch we found.
 627  */
 628 static struct microcode_intel *__load_ucode_intel(struct ucode_cpu_info *uci)
 629 {
 630         static const char *path;
 631         struct cpio_data cp;
 632         bool use_pa;
 633
 634         if (IS_ENABLED(CONFIG_X86_32)) {
 635                 path      = (const char *)__pa_nodebug(ucode_path);
 636                 use_pa    = true;
 637         } else {
 638                 path      = ucode_path;
 639                 use_pa    = false;
 640         }
 641
 642         /* try built-in microcode first */
 643         if (!load_builtin_intel_microcode(&cp))
 644                 cp = find_microcode_in_initrd(path, use_pa);
 645
 646         if (!(cp.data && cp.size))
 647                 return NULL;
 648
 649         collect_cpu_info_early(uci);
 650
 651         return scan_microcode(cp.data, cp.size, uci, false);
 652 }
 653
 654 void __init load_ucode_intel_bsp(void)
 655 {
 656         struct microcode_intel *patch;
 657         struct ucode_cpu_info uci;
 658
 659         patch = __load_ucode_intel(&uci);
 660         if (!patch)
 661                 return;
 662
 663         uci.mc = patch;
 664
 665         apply_microcode_early(&uci, true);
 666 }
 667
 668 void load_ucode_intel_ap(void)
 669 {
 670         struct microcode_intel *patch, **iup;
 671         struct ucode_cpu_info uci;
 672
 673         if (IS_ENABLED(CONFIG_X86_32))
 674                 iup = (struct microcode_intel **) __pa_nodebug(&intel_ucode_patch);
 675         else
 676                 iup = &intel_ucode_patch;
 677
 678 reget:
 679         if (!*iup) {
 680                 patch = __load_ucode_intel(&uci);
 681                 if (!patch)
 682                         return;
 683
 684                 *iup = patch;
 685         }
 686
 687         uci.mc = *iup;
 688
 689         if (apply_microcode_early(&uci, true)) {
 690                 /* Mixed-silicon system? Try to refetch the proper patch: */
 691                 *iup = NULL;
 692
 693                 goto reget;
 694         }
 695 }
 696
 697 static struct microcode_intel *find_patch(struct ucode_cpu_info *uci)
 698 {
 699         struct microcode_header_intel *phdr;
 700         struct ucode_patch *iter, *tmp;
 701
 702         list_for_each_entry_safe(iter, tmp, &microcode_cache, plist) {
 703
 704                 phdr = (struct microcode_header_intel *)iter->data;
 705
 706                 if (phdr->rev <= uci->cpu_sig.rev)
 707                         continue;
 708
 709                 if (!find_matching_signature(phdr,
 710                                              uci->cpu_sig.sig,
 711                                              uci->cpu_sig.pf))
 712                         continue;
 713
 714                 return iter->data;
 715         }
 716         return NULL;
 717 }
 718
 719 void reload_ucode_intel(void)
 720 {
 721         struct microcode_intel *p;
 722         struct ucode_cpu_info uci;
 723
 724         collect_cpu_info_early(&uci);
 725
 726         p = find_patch(&uci);
 727         if (!p)
 728                 return;
 729
 730         uci.mc = p;
 731
 732         apply_microcode_early(&uci, false);
 733 }
 734
 735 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 736 {
 737         static struct cpu_signature prev;
 738         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
 739         unsigned int val[2];
 740
 741         memset(csig, 0, sizeof(*csig));
 742
 743         csig->sig = cpuid_eax(0x00000001);
 744
 745         if ((c->x86_model >= 5) || (c->x86 > 6)) {
 746                 /* get processor flags from MSR 0x17 */
 747                 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
 748                 csig->pf = 1 << ((val[1] >> 18) & 7);
 749         }
 750
 751         csig->rev = c->microcode;
 752
 753         /* No extra locking on prev, races are harmless. */
 754         if (csig->sig != prev.sig || csig->pf != prev.pf || csig->rev != prev.rev) {
 755                 pr_info("sig=0x%x, pf=0x%x, revision=0x%x\n",
 756                         csig->sig, csig->pf, csig->rev);
 757                 prev = *csig;
 758         }
 759
 760         return 0;
 761 }
 762
 763 static int apply_microcode_intel(int cpu)
 764 {
 765         struct microcode_intel *mc;
 766         struct ucode_cpu_info *uci;
 767         struct cpuinfo_x86 *c;
 768         static int prev_rev;
 769         u32 rev;
 770
 771         /* We should bind the task to the CPU */
 772         if (WARN_ON(raw_smp_processor_id() != cpu))
 773                 return -1;
 774
 775         uci = ucode_cpu_info + cpu;
 776         mc = uci->mc;
 777         if (!mc) {
 778                 /* Look for a newer patch in our cache: */
 779                 mc = find_patch(uci);
 780                 if (!mc)
 781                         return 0;
 782         }
 783
 784         /* write microcode via MSR 0x79 */
 785         wrmsrl(MSR_IA32_UCODE_WRITE, (unsigned long)mc->bits);
 786
 787         rev = intel_get_microcode_revision();
 788
 789         if (rev != mc->hdr.rev) {
 790                 pr_err("CPU%d update to revision 0x%x failed\n",
 791                        cpu, mc->hdr.rev);
 792                 return -1;
 793         }
 794
 795         if (rev != prev_rev) {
 796                 pr_info("updated to revision 0x%x, date = %04x-%02x-%02x\n",
 797                         rev,
 798                         mc->hdr.date & 0xffff,
 799                         mc->hdr.date >> 24,
 800                         (mc->hdr.date >> 16) & 0xff);
 801                 prev_rev = rev;
 802         }
 803
 804         c = &cpu_data(cpu);
 805
 806         uci->cpu_sig.rev = rev;
 807         c->microcode = rev;
 808
 809         return 0;
 810 }
 811
 812 static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 813                                 int (*get_ucode_data)(void *, const void *, size_t))
 814 {
 815         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 816         u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
 817         int new_rev = uci->cpu_sig.rev;
 818         unsigned int leftover = size;
 819         unsigned int curr_mc_size = 0, new_mc_size = 0;
 820         unsigned int csig, cpf;
 821
 822         while (leftover) {
 823                 struct microcode_header_intel mc_header;
 824                 unsigned int mc_size;
 825
 826                 if (leftover < sizeof(mc_header)) {
 827                         pr_err("error! Truncated header in microcode data file\n");
 828                         break;
 829                 }
 830
 831                 if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
 832                         break;
 833
 834                 mc_size = get_totalsize(&mc_header);
 835                 if (!mc_size || mc_size > leftover) {
 836                         pr_err("error! Bad data in microcode data file\n");
 837                         break;
 838                 }
 839
 840                 /* For performance reasons, reuse mc area when possible */
 841                 if (!mc || mc_size > curr_mc_size) {
 842                         vfree(mc);
 843                         mc = vmalloc(mc_size);
 844                         if (!mc)
 845                                 break;
 846                         curr_mc_size = mc_size;
 847                 }
 848
 849                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
 850                     microcode_sanity_check(mc, 1) < 0) {
 851                         break;
 852                 }
 853
 854                 csig = uci->cpu_sig.sig;
 855                 cpf = uci->cpu_sig.pf;
 856                 if (has_newer_microcode(mc, csig, cpf, new_rev)) {
 857                         vfree(new_mc);
 858                         new_rev = mc_header.rev;
 859                         new_mc  = mc;
 860                         new_mc_size = mc_size;
 861                         mc = NULL;      /* trigger new vmalloc */
 862                 }
 863
 864                 ucode_ptr += mc_size;
 865                 leftover  -= mc_size;
 866         }
 867
 868         vfree(mc);
 869
 870         if (leftover) {
 871                 vfree(new_mc);
 872                 return UCODE_ERROR;
 873         }
 874
 875         if (!new_mc)
 876                 return UCODE_NFOUND;
 877
 878         vfree(uci->mc);
 879         uci->mc = (struct microcode_intel *)new_mc;
 880
 881         /*
 882          * If early loading microcode is supported, save this mc into
 883          * permanent memory. So it will be loaded early when a CPU is hot added
 884          * or resumes.
 885          */
 886         save_mc_for_early(new_mc, new_mc_size);
 887
 888         pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
 889                  cpu, new_rev, uci->cpu_sig.rev);
 890
 891         return UCODE_OK;
 892 }
 893
 894 static int get_ucode_fw(void *to, const void *from, size_t n)
 895 {
 896         memcpy(to, from, n);
 897         return 0;
 898 }
 899
 900 static enum ucode_state request_microcode_fw(int cpu, struct device *device,
 901                                              bool refresh_fw)
 902 {
 903         char name[30];
 904         struct cpuinfo_x86 *c = &cpu_data(cpu);
 905         const struct firmware *firmware;
 906         enum ucode_state ret;
 907
 908         sprintf(name, "intel-ucode/%02x-%02x-%02x",
 909                 c->x86, c->x86_model, c->x86_mask);
 910
 911         if (request_firmware_direct(&firmware, name, device)) {
 912                 pr_debug("data file %s load failed\n", name);
 913                 return UCODE_NFOUND;
 914         }
 915
 916         ret = generic_load_microcode(cpu, (void *)firmware->data,
 917                                      firmware->size, &get_ucode_fw);
 918
 919         release_firmware(firmware);
 920
 921         return ret;
 922 }
 923
 924 static int get_ucode_user(void *to, const void *from, size_t n)
 925 {
 926         return copy_from_user(to, from, n);
 927 }
 928
 929 static enum ucode_state
 930 request_microcode_user(int cpu, const void __user *buf, size_t size)
 931 {
 932         return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
 933 }
 934
 935 static struct microcode_ops microcode_intel_ops = {
 936         .request_microcode_user           = request_microcode_user,
 937         .request_microcode_fw             = request_microcode_fw,
 938         .collect_cpu_info                 = collect_cpu_info,
 939         .apply_microcode                  = apply_microcode_intel,
 940 };
 941
 942 struct microcode_ops * __init init_intel_microcode(void)
 943 {
 944         struct cpuinfo_x86 *c = &boot_cpu_data;
 945
 946         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
 947             cpu_has(c, X86_FEATURE_IA64)) {
 948                 pr_err("Intel CPU family 0x%x not supported\n", c->x86);
 949                 return NULL;
 950         }
 951
 952         return &microcode_intel_ops;
 953 }