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/design/pentium4/manuals/253668.htm
  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 #include <linux/firmware.h>
  74 #include <linux/uaccess.h>
  75 #include <linux/kernel.h>
  76 #include <linux/module.h>
  77 #include <linux/vmalloc.h>
  78
  79 #include <asm/microcode.h>
  80 #include <asm/processor.h>
  81 #include <asm/msr.h>
  82
  83 MODULE_DESCRIPTION("Microcode Update Driver");
  84 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
  85 MODULE_LICENSE("GPL");
  86
  87 struct microcode_header_intel {
  88         unsigned int            hdrver;
  89         unsigned int            rev;
  90         unsigned int            date;
  91         unsigned int            sig;
  92         unsigned int            cksum;
  93         unsigned int            ldrver;
  94         unsigned int            pf;
  95         unsigned int            datasize;
  96         unsigned int            totalsize;
  97         unsigned int            reserved[3];
  98 };
  99
 100 struct microcode_intel {
 101         struct microcode_header_intel hdr;
 102         unsigned int            bits[0];
 103 };
 104
 105 /* microcode format is extended from prescott processors */
 106 struct extended_signature {
 107         unsigned int            sig;
 108         unsigned int            pf;
 109         unsigned int            cksum;
 110 };
 111
 112 struct extended_sigtable {
 113         unsigned int            count;
 114         unsigned int            cksum;
 115         unsigned int            reserved[3];
 116         struct extended_signature sigs[0];
 117 };
 118
 119 #define DEFAULT_UCODE_DATASIZE  (2000)
 120 #define MC_HEADER_SIZE          (sizeof(struct microcode_header_intel))
 121 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
 122 #define EXT_HEADER_SIZE         (sizeof(struct extended_sigtable))
 123 #define EXT_SIGNATURE_SIZE      (sizeof(struct extended_signature))
 124 #define DWSIZE                  (sizeof(u32))
 125
 126 #define get_totalsize(mc) \
 127         (((struct microcode_intel *)mc)->hdr.totalsize ? \
 128          ((struct microcode_intel *)mc)->hdr.totalsize : \
 129          DEFAULT_UCODE_TOTALSIZE)
 130
 131 #define get_datasize(mc) \
 132         (((struct microcode_intel *)mc)->hdr.datasize ? \
 133          ((struct microcode_intel *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
 134
 135 #define sigmatch(s1, s2, p1, p2) \
 136         (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
 137
 138 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
 139
 140 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 141 {
 142         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
 143         unsigned int val[2];
 144
 145         memset(csig, 0, sizeof(*csig));
 146
 147         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
 148             cpu_has(c, X86_FEATURE_IA64)) {
 149                 printk(KERN_ERR "microcode: CPU%d not a capable Intel "
 150                         "processor\n", cpu_num);
 151                 return -1;
 152         }
 153
 154         csig->sig = cpuid_eax(0x00000001);
 155
 156         if ((c->x86_model >= 5) || (c->x86 > 6)) {
 157                 /* get processor flags from MSR 0x17 */
 158                 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
 159                 csig->pf = 1 << ((val[1] >> 18) & 7);
 160         }
 161
 162         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 163         /* see notes above for revision 1.07.  Apparent chip bug */
 164         sync_core();
 165         /* get the current revision from MSR 0x8B */
 166         rdmsr(MSR_IA32_UCODE_REV, val[0], csig->rev);
 167
 168         printk(KERN_INFO "microcode: CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n",
 169                         cpu_num, csig->sig, csig->pf, csig->rev);
 170
 171         return 0;
 172 }
 173
 174 static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
 175 {
 176         return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
 177 }
 178
 179 static inline int
 180 update_match_revision(struct microcode_header_intel *mc_header, int rev)
 181 {
 182         return (mc_header->rev <= rev) ? 0 : 1;
 183 }
 184
 185 static int microcode_sanity_check(void *mc)
 186 {
 187         unsigned long total_size, data_size, ext_table_size;
 188         struct microcode_header_intel *mc_header = mc;
 189         struct extended_sigtable *ext_header = NULL;
 190         int sum, orig_sum, ext_sigcount = 0, i;
 191         struct extended_signature *ext_sig;
 192
 193         total_size = get_totalsize(mc_header);
 194         data_size = get_datasize(mc_header);
 195
 196         if (data_size + MC_HEADER_SIZE > total_size) {
 197                 printk(KERN_ERR "microcode: error! "
 198                                 "Bad data size in microcode data file\n");
 199                 return -EINVAL;
 200         }
 201
 202         if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
 203                 printk(KERN_ERR "microcode: error! "
 204                                 "Unknown microcode update format\n");
 205                 return -EINVAL;
 206         }
 207         ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
 208         if (ext_table_size) {
 209                 if ((ext_table_size < EXT_HEADER_SIZE)
 210                  || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
 211                         printk(KERN_ERR "microcode: error! "
 212                                 "Small exttable size in microcode data file\n");
 213                         return -EINVAL;
 214                 }
 215                 ext_header = mc + MC_HEADER_SIZE + data_size;
 216                 if (ext_table_size != exttable_size(ext_header)) {
 217                         printk(KERN_ERR "microcode: error! "
 218                                 "Bad exttable size in microcode data file\n");
 219                         return -EFAULT;
 220                 }
 221                 ext_sigcount = ext_header->count;
 222         }
 223
 224         /* check extended table checksum */
 225         if (ext_table_size) {
 226                 int ext_table_sum = 0;
 227                 int *ext_tablep = (int *)ext_header;
 228
 229                 i = ext_table_size / DWSIZE;
 230                 while (i--)
 231                         ext_table_sum += ext_tablep[i];
 232                 if (ext_table_sum) {
 233                         printk(KERN_WARNING "microcode: aborting, "
 234                                 "bad extended signature table checksum\n");
 235                         return -EINVAL;
 236                 }
 237         }
 238
 239         /* calculate the checksum */
 240         orig_sum = 0;
 241         i = (MC_HEADER_SIZE + data_size) / DWSIZE;
 242         while (i--)
 243                 orig_sum += ((int *)mc)[i];
 244         if (orig_sum) {
 245                 printk(KERN_ERR "microcode: aborting, bad checksum\n");
 246                 return -EINVAL;
 247         }
 248         if (!ext_table_size)
 249                 return 0;
 250         /* check extended signature checksum */
 251         for (i = 0; i < ext_sigcount; i++) {
 252                 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
 253                           EXT_SIGNATURE_SIZE * i;
 254                 sum = orig_sum
 255                         - (mc_header->sig + mc_header->pf + mc_header->cksum)
 256                         + (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
 257                 if (sum) {
 258                         printk(KERN_ERR "microcode: aborting, bad checksum\n");
 259                         return -EINVAL;
 260                 }
 261         }
 262         return 0;
 263 }
 264
 265 /*
 266  * return 0 - no update found
 267  * return 1 - found update
 268  */
 269 static int
 270 get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
 271 {
 272         struct microcode_header_intel *mc_header = mc;
 273         struct extended_sigtable *ext_header;
 274         unsigned long total_size = get_totalsize(mc_header);
 275         int ext_sigcount, i;
 276         struct extended_signature *ext_sig;
 277
 278         if (!update_match_revision(mc_header, rev))
 279                 return 0;
 280
 281         if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
 282                 return 1;
 283
 284         /* Look for ext. headers: */
 285         if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
 286                 return 0;
 287
 288         ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
 289         ext_sigcount = ext_header->count;
 290         ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 291
 292         for (i = 0; i < ext_sigcount; i++) {
 293                 if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
 294                         return 1;
 295                 ext_sig++;
 296         }
 297         return 0;
 298 }
 299
 300 static int apply_microcode(int cpu)
 301 {
 302         struct microcode_intel *mc_intel;
 303         struct ucode_cpu_info *uci;
 304         unsigned int val[2];
 305         int cpu_num;
 306
 307         cpu_num = raw_smp_processor_id();
 308         uci = ucode_cpu_info + cpu;
 309         mc_intel = uci->mc;
 310
 311         /* We should bind the task to the CPU */
 312         BUG_ON(cpu_num != cpu);
 313
 314         if (mc_intel == NULL)
 315                 return 0;
 316
 317         /* write microcode via MSR 0x79 */
 318         wrmsr(MSR_IA32_UCODE_WRITE,
 319               (unsigned long) mc_intel->bits,
 320               (unsigned long) mc_intel->bits >> 16 >> 16);
 321         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 322
 323         /* see notes above for revision 1.07.  Apparent chip bug */
 324         sync_core();
 325
 326         /* get the current revision from MSR 0x8B */
 327         rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
 328
 329         if (val[1] != mc_intel->hdr.rev) {
 330                 printk(KERN_ERR "microcode: CPU%d update "
 331                                 "to revision 0x%x failed\n",
 332                         cpu_num, mc_intel->hdr.rev);
 333                 return -1;
 334         }
 335         printk(KERN_INFO "microcode: CPU%d updated to revision "
 336                          "0x%x, date = %04x-%02x-%02x \n",
 337                 cpu_num, val[1],
 338                 mc_intel->hdr.date & 0xffff,
 339                 mc_intel->hdr.date >> 24,
 340                 (mc_intel->hdr.date >> 16) & 0xff);
 341
 342         uci->cpu_sig.rev = val[1];
 343
 344         return 0;
 345 }
 346
 347 static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
 348                                 int (*get_ucode_data)(void *, const void *, size_t))
 349 {
 350         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 351         u8 *ucode_ptr = data, *new_mc = NULL, *mc;
 352         int new_rev = uci->cpu_sig.rev;
 353         unsigned int leftover = size;
 354         enum ucode_state state = UCODE_OK;
 355
 356         while (leftover) {
 357                 struct microcode_header_intel mc_header;
 358                 unsigned int mc_size;
 359
 360                 if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
 361                         break;
 362
 363                 mc_size = get_totalsize(&mc_header);
 364                 if (!mc_size || mc_size > leftover) {
 365                         printk(KERN_ERR "microcode: error!"
 366                                         "Bad data in microcode data file\n");
 367                         break;
 368                 }
 369
 370                 mc = vmalloc(mc_size);
 371                 if (!mc)
 372                         break;
 373
 374                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
 375                     microcode_sanity_check(mc) < 0) {
 376                         vfree(mc);
 377                         break;
 378                 }
 379
 380                 if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
 381                         if (new_mc)
 382                                 vfree(new_mc);
 383                         new_rev = mc_header.rev;
 384                         new_mc  = mc;
 385                 } else
 386                         vfree(mc);
 387
 388                 ucode_ptr += mc_size;
 389                 leftover  -= mc_size;
 390         }
 391
 392         if (leftover) {
 393                 if (new_mc)
 394                         vfree(new_mc);
 395                 state = UCODE_ERROR;
 396                 goto out;
 397         }
 398
 399         if (!new_mc) {
 400                 state = UCODE_NFOUND;
 401                 goto out;
 402         }
 403
 404         if (uci->mc)
 405                 vfree(uci->mc);
 406         uci->mc = (struct microcode_intel *)new_mc;
 407
 408         pr_debug("microcode: CPU%d found a matching microcode update with"
 409                  " version 0x%x (current=0x%x)\n",
 410                         cpu, new_rev, uci->cpu_sig.rev);
 411 out:
 412         return state;
 413 }
 414
 415 static int get_ucode_fw(void *to, const void *from, size_t n)
 416 {
 417         memcpy(to, from, n);
 418         return 0;
 419 }
 420
 421 static enum ucode_state request_microcode_fw(int cpu, struct device *device)
 422 {
 423         char name[30];
 424         struct cpuinfo_x86 *c = &cpu_data(cpu);
 425         const struct firmware *firmware;
 426         enum ucode_state ret;
 427
 428         sprintf(name, "intel-ucode/%02x-%02x-%02x",
 429                 c->x86, c->x86_model, c->x86_mask);
 430
 431         if (request_firmware(&firmware, name, device)) {
 432                 pr_debug("microcode: data file %s load failed\n", name);
 433                 return UCODE_NFOUND;
 434         }
 435
 436         ret = generic_load_microcode(cpu, (void *)firmware->data,
 437                                      firmware->size, &get_ucode_fw);
 438
 439         release_firmware(firmware);
 440
 441         return ret;
 442 }
 443
 444 static int get_ucode_user(void *to, const void *from, size_t n)
 445 {
 446         return copy_from_user(to, from, n);
 447 }
 448
 449 static enum ucode_state
 450 request_microcode_user(int cpu, const void __user *buf, size_t size)
 451 {
 452         return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
 453 }
 454
 455 static void microcode_fini_cpu(int cpu)
 456 {
 457         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 458
 459         vfree(uci->mc);
 460         uci->mc = NULL;
 461 }
 462
 463 static struct microcode_ops microcode_intel_ops = {
 464         .request_microcode_user           = request_microcode_user,
 465         .request_microcode_fw             = request_microcode_fw,
 466         .collect_cpu_info                 = collect_cpu_info,
 467         .apply_microcode                  = apply_microcode,
 468         .microcode_fini_cpu               = microcode_fini_cpu,
 469 };
 470
 471 struct microcode_ops * __init init_intel_microcode(void)
 472 {
 473         return &microcode_intel_ops;
 474 }
 475