arch/x86/kernel/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  *      This driver allows to upgrade microcode on Intel processors
   8  *      belonging to IA-32 family - PentiumPro, Pentium II,
   9  *      Pentium III, Xeon, Pentium 4, etc.
  10  *
  11  *      Reference: Section 8.11 of Volume 3a, IA-32 Intel? Architecture
  12  *      Software Developer's Manual
  13  *      Order Number 253668 or free download from:
  14  *
  15  *      http://developer.intel.com/Assets/PDF/manual/253668.pdf
  16  *
  17  *      For more information, go to http://www.urbanmyth.org/microcode
  18  *
  19  *      This program is free software; you can redistribute it and/or
  20  *      modify it under the terms of the GNU General Public License
  21  *      as published by the Free Software Foundation; either version
  22  *      2 of the License, or (at your option) any later version.
  23  *
  24  *      1.0     16 Feb 2000, Tigran Aivazian <tigran@sco.com>
  25  *              Initial release.
  26  *      1.01    18 Feb 2000, Tigran Aivazian <tigran@sco.com>
  27  *              Added read() support + cleanups.
  28  *      1.02    21 Feb 2000, Tigran Aivazian <tigran@sco.com>
  29  *              Added 'device trimming' support. open(O_WRONLY) zeroes
  30  *              and frees the saved copy of applied microcode.
  31  *      1.03    29 Feb 2000, Tigran Aivazian <tigran@sco.com>
  32  *              Made to use devfs (/dev/cpu/microcode) + cleanups.
  33  *      1.04    06 Jun 2000, Simon Trimmer <simon@veritas.com>
  34  *              Added misc device support (now uses both devfs and misc).
  35  *              Added MICROCODE_IOCFREE ioctl to clear memory.
  36  *      1.05    09 Jun 2000, Simon Trimmer <simon@veritas.com>
  37  *              Messages for error cases (non Intel & no suitable microcode).
  38  *      1.06    03 Aug 2000, Tigran Aivazian <tigran@veritas.com>
  39  *              Removed ->release(). Removed exclusive open and status bitmap.
  40  *              Added microcode_rwsem to serialize read()/write()/ioctl().
  41  *              Removed global kernel lock usage.
  42  *      1.07    07 Sep 2000, Tigran Aivazian <tigran@veritas.com>
  43  *              Write 0 to 0x8B msr and then cpuid before reading revision,
  44  *              so that it works even if there were no update done by the
  45  *              BIOS. Otherwise, reading from 0x8B gives junk (which happened
  46  *              to be 0 on my machine which is why it worked even when I
  47  *              disabled update by the BIOS)
  48  *              Thanks to Eric W. Biederman <ebiederman@lnxi.com> for the fix.
  49  *      1.08    11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and
  50  *                           Tigran Aivazian <tigran@veritas.com>
  51  *              Intel Pentium 4 processor support and bugfixes.
  52  *      1.09    30 Oct 2001, Tigran Aivazian <tigran@veritas.com>
  53  *              Bugfix for HT (Hyper-Threading) enabled processors
  54  *              whereby processor resources are shared by all logical processors
  55  *              in a single CPU package.
  56  *      1.10    28 Feb 2002 Asit K Mallick <asit.k.mallick@intel.com> and
  57  *              Tigran Aivazian <tigran@veritas.com>,
  58  *              Serialize updates as required on HT processors due to
  59  *              speculative nature of implementation.
  60  *      1.11    22 Mar 2002 Tigran Aivazian <tigran@veritas.com>
  61  *              Fix the panic when writing zero-length microcode chunk.
  62  *      1.12    29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>,
  63  *              Jun Nakajima <jun.nakajima@intel.com>
  64  *              Support for the microcode updates in the new format.
  65  *      1.13    10 Oct 2003 Tigran Aivazian <tigran@veritas.com>
  66  *              Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl
  67  *              because we no longer hold a copy of applied microcode
  68  *              in kernel memory.
  69  *      1.14    25 Jun 2004 Tigran Aivazian <tigran@veritas.com>
  70  *              Fix sigmatch() macro to handle old CPUs with pf == 0.
  71  *              Thanks to Stuart Swales for pointing out this bug.
  72  */
  73
  74 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  75
  76 #include <linux/firmware.h>
  77 #include <linux/uaccess.h>
  78 #include <linux/kernel.h>
  79 #include <linux/module.h>
  80 #include <linux/vmalloc.h>
  81
  82 #include <asm/microcode.h>
  83 #include <asm/processor.h>
  84 #include <asm/msr.h>
  85
  86 MODULE_DESCRIPTION("Microcode Update Driver");
  87 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
  88 MODULE_LICENSE("GPL");
  89
  90 struct microcode_header_intel {
  91         unsigned int            hdrver;
  92         unsigned int            rev;
  93         unsigned int            date;
  94         unsigned int            sig;
  95         unsigned int            cksum;
  96         unsigned int            ldrver;
  97         unsigned int            pf;
  98         unsigned int            datasize;
  99         unsigned int            totalsize;
 100         unsigned int            reserved[3];
 101 };
 102
 103 struct microcode_intel {
 104         struct microcode_header_intel hdr;
 105         unsigned int            bits[0];
 106 };
 107
 108 /* microcode format is extended from prescott processors */
 109 struct extended_signature {
 110         unsigned int            sig;
 111         unsigned int            pf;
 112         unsigned int            cksum;
 113 };
 114
 115 struct extended_sigtable {
 116         unsigned int            count;
 117         unsigned int            cksum;
 118         unsigned int            reserved[3];
 119         struct extended_signature sigs[0];
 120 };
 121
 122 #define DEFAULT_UCODE_DATASIZE  (2000)
 123 #define MC_HEADER_SIZE          (sizeof(struct microcode_header_intel))
 124 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
 125 #define EXT_HEADER_SIZE         (sizeof(struct extended_sigtable))
 126 #define EXT_SIGNATURE_SIZE      (sizeof(struct extended_signature))
 127 #define DWSIZE                  (sizeof(u32))
 128
 129 #define get_totalsize(mc) \
 130         (((struct microcode_intel *)mc)->hdr.totalsize ? \
 131          ((struct microcode_intel *)mc)->hdr.totalsize : \
 132          DEFAULT_UCODE_TOTALSIZE)
 133
 134 #define get_datasize(mc) \
 135         (((struct microcode_intel *)mc)->hdr.datasize ? \
 136          ((struct microcode_intel *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
 137
 138 #define sigmatch(s1, s2, p1, p2) \
 139         (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
 140
 141 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
 142
 143 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 144 {
 145         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
 146         unsigned int val[2];
 147
 148         memset(csig, 0, sizeof(*csig));
 149
 150         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
 151             cpu_has(c, X86_FEATURE_IA64)) {
 152                 pr_err("CPU%d not a capable Intel processor\n", cpu_num);
 153                 return -1;
 154         }
 155
 156         csig->sig = cpuid_eax(0x00000001);
 157
 158         if ((c->x86_model >= 5) || (c->x86 > 6)) {
 159                 /* get processor flags from MSR 0x17 */
 160                 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
 161                 csig->pf = 1 << ((val[1] >> 18) & 7);
 162         }
 163
 164         csig->rev = c->microcode;
 165         pr_info("CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n",
 166                 cpu_num, csig->sig, csig->pf, csig->rev);
 167
 168         return 0;
 169 }
 170
 171 static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
 172 {
 173         return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
 174 }
 175
 176 static inline int
 177 update_match_revision(struct microcode_header_intel *mc_header, int rev)
 178 {
 179         return (mc_header->rev <= rev) ? 0 : 1;
 180 }
 181
 182 static int microcode_sanity_check(void *mc)
 183 {
 184         unsigned long total_size, data_size, ext_table_size;
 185         struct microcode_header_intel *mc_header = mc;
 186         struct extended_sigtable *ext_header = NULL;
 187         int sum, orig_sum, ext_sigcount = 0, i;
 188         struct extended_signature *ext_sig;
 189
 190         total_size = get_totalsize(mc_header);
 191         data_size = get_datasize(mc_header);
 192
 193         if (data_size + MC_HEADER_SIZE > total_size) {
 194                 pr_err("error! Bad data size in microcode data file\n");
 195                 return -EINVAL;
 196         }
 197
 198         if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
 199                 pr_err("error! Unknown microcode update format\n");
 200                 return -EINVAL;
 201         }
 202         ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
 203         if (ext_table_size) {
 204                 if ((ext_table_size < EXT_HEADER_SIZE)
 205                  || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
 206                         pr_err("error! Small exttable size in microcode data file\n");
 207                         return -EINVAL;
 208                 }
 209                 ext_header = mc + MC_HEADER_SIZE + data_size;
 210                 if (ext_table_size != exttable_size(ext_header)) {
 211                         pr_err("error! Bad exttable size in microcode data file\n");
 212                         return -EFAULT;
 213                 }
 214                 ext_sigcount = ext_header->count;
 215         }
 216
 217         /* check extended table checksum */
 218         if (ext_table_size) {
 219                 int ext_table_sum = 0;
 220                 int *ext_tablep = (int *)ext_header;
 221
 222                 i = ext_table_size / DWSIZE;
 223                 while (i--)
 224                         ext_table_sum += ext_tablep[i];
 225                 if (ext_table_sum) {
 226                         pr_warning("aborting, bad extended signature table checksum\n");
 227                         return -EINVAL;
 228                 }
 229         }
 230
 231         /* calculate the checksum */
 232         orig_sum = 0;
 233         i = (MC_HEADER_SIZE + data_size) / DWSIZE;
 234         while (i--)
 235                 orig_sum += ((int *)mc)[i];
 236         if (orig_sum) {
 237                 pr_err("aborting, bad checksum\n");
 238                 return -EINVAL;
 239         }
 240         if (!ext_table_size)
 241                 return 0;
 242         /* check extended signature checksum */
 243         for (i = 0; i < ext_sigcount; i++) {
 244                 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
 245                           EXT_SIGNATURE_SIZE * i;
 246                 sum = orig_sum
 247                         - (mc_header->sig + mc_header->pf + mc_header->cksum)
 248                         + (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
 249                 if (sum) {
 250                         pr_err("aborting, bad checksum\n");
 251                         return -EINVAL;
 252                 }
 253         }
 254         return 0;
 255 }
 256
 257 /*
 258  * return 0 - no update found
 259  * return 1 - found update
 260  */
 261 static int
 262 get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
 263 {
 264         struct microcode_header_intel *mc_header = mc;
 265         struct extended_sigtable *ext_header;
 266         unsigned long total_size = get_totalsize(mc_header);
 267         int ext_sigcount, i;
 268         struct extended_signature *ext_sig;
 269
 270         if (!update_match_revision(mc_header, rev))
 271                 return 0;
 272
 273         if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
 274                 return 1;
 275
 276         /* Look for ext. headers: */
 277         if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
 278                 return 0;
 279
 280         ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
 281         ext_sigcount = ext_header->count;
 282         ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 283
 284         for (i = 0; i < ext_sigcount; i++) {
 285                 if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
 286                         return 1;
 287                 ext_sig++;
 288         }
 289         return 0;
 290 }
 291
 292 static int apply_microcode(int cpu)
 293 {
 294         struct microcode_intel *mc_intel;
 295         struct ucode_cpu_info *uci;
 296         unsigned int val[2];
 297         int cpu_num = raw_smp_processor_id();
 298         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
 299
 300         uci = ucode_cpu_info + cpu;
 301         mc_intel = uci->mc;
 302
 303         /* We should bind the task to the CPU */
 304         BUG_ON(cpu_num != cpu);
 305
 306         if (mc_intel == NULL)
 307                 return 0;
 308
 309         /* write microcode via MSR 0x79 */
 310         wrmsr(MSR_IA32_UCODE_WRITE,
 311               (unsigned long) mc_intel->bits,
 312               (unsigned long) mc_intel->bits >> 16 >> 16);
 313         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 314
 315         /* As documented in the SDM: Do a CPUID 1 here */
 316         sync_core();
 317
 318         /* get the current revision from MSR 0x8B */
 319         rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
 320
 321         if (val[1] != mc_intel->hdr.rev) {
 322                 pr_err("CPU%d update to revision 0x%x failed\n",
 323                        cpu_num, mc_intel->hdr.rev);
 324                 return -1;
 325         }
 326         pr_info("CPU%d updated to revision 0x%x, date = %04x-%02x-%02x\n",
 327                 cpu_num, val[1],
 328                 mc_intel->hdr.date & 0xffff,
 329                 mc_intel->hdr.date >> 24,
 330                 (mc_intel->hdr.date >> 16) & 0xff);
 331
 332         uci->cpu_sig.rev = val[1];
 333         c->microcode = val[1];
 334
 335         return 0;
 336 }
 337
 338 static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 339                                 int (*get_ucode_data)(void *, const void *, size_t))
 340 {
 341         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 342         u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
 343         int new_rev = uci->cpu_sig.rev;
 344         unsigned int leftover = size;
 345         enum ucode_state state = UCODE_OK;
 346         unsigned int curr_mc_size = 0;
 347
 348         while (leftover) {
 349                 struct microcode_header_intel mc_header;
 350                 unsigned int mc_size;
 351
 352                 if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
 353                         break;
 354
 355                 mc_size = get_totalsize(&mc_header);
 356                 if (!mc_size || mc_size > leftover) {
 357                         pr_err("error! Bad data in microcode data file\n");
 358                         break;
 359                 }
 360
 361                 /* For performance reasons, reuse mc area when possible */
 362                 if (!mc || mc_size > curr_mc_size) {
 363                         vfree(mc);
 364                         mc = vmalloc(mc_size);
 365                         if (!mc)
 366                                 break;
 367                         curr_mc_size = mc_size;
 368                 }
 369
 370                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
 371                     microcode_sanity_check(mc) < 0) {
 372                         break;
 373                 }
 374
 375                 if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
 376                         vfree(new_mc);
 377                         new_rev = mc_header.rev;
 378                         new_mc  = mc;
 379                         mc = NULL;      /* trigger new vmalloc */
 380                 }
 381
 382                 ucode_ptr += mc_size;
 383                 leftover  -= mc_size;
 384         }
 385
 386         vfree(mc);
 387
 388         if (leftover) {
 389                 vfree(new_mc);
 390                 state = UCODE_ERROR;
 391                 goto out;
 392         }
 393
 394         if (!new_mc) {
 395                 state = UCODE_NFOUND;
 396                 goto out;
 397         }
 398
 399         vfree(uci->mc);
 400         uci->mc = (struct microcode_intel *)new_mc;
 401
 402         pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
 403                  cpu, new_rev, uci->cpu_sig.rev);
 404 out:
 405         return state;
 406 }
 407
 408 static int get_ucode_fw(void *to, const void *from, size_t n)
 409 {
 410         memcpy(to, from, n);
 411         return 0;
 412 }
 413
 414 static enum ucode_state request_microcode_fw(int cpu, struct device *device)
 415 {
 416         char name[30];
 417         struct cpuinfo_x86 *c = &cpu_data(cpu);
 418         const struct firmware *firmware;
 419         enum ucode_state ret;
 420
 421         sprintf(name, "intel-ucode/%02x-%02x-%02x",
 422                 c->x86, c->x86_model, c->x86_mask);
 423
 424         if (request_firmware(&firmware, name, device)) {
 425                 pr_debug("data file %s load failed\n", name);
 426                 return UCODE_NFOUND;
 427         }
 428
 429         ret = generic_load_microcode(cpu, (void *)firmware->data,
 430                                      firmware->size, &get_ucode_fw);
 431
 432         release_firmware(firmware);
 433
 434         return ret;
 435 }
 436
 437 static int get_ucode_user(void *to, const void *from, size_t n)
 438 {
 439         return copy_from_user(to, from, n);
 440 }
 441
 442 static enum ucode_state
 443 request_microcode_user(int cpu, const void __user *buf, size_t size)
 444 {
 445         return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
 446 }
 447
 448 static void microcode_fini_cpu(int cpu)
 449 {
 450         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 451
 452         vfree(uci->mc);
 453         uci->mc = NULL;
 454 }
 455
 456 static struct microcode_ops microcode_intel_ops = {
 457         .request_microcode_user           = request_microcode_user,
 458         .request_microcode_fw             = request_microcode_fw,
 459         .collect_cpu_info                 = collect_cpu_info,
 460         .apply_microcode                  = apply_microcode,
 461         .microcode_fini_cpu               = microcode_fini_cpu,
 462 };
 463
 464 struct microcode_ops * __init init_intel_microcode(void)
 465 {
 466         return &microcode_intel_ops;
 467 }
 468