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/capability.h>
  74 #include <linux/kernel.h>
  75 #include <linux/init.h>
  76 #include <linux/sched.h>
  77 #include <linux/smp_lock.h>
  78 #include <linux/cpumask.h>
  79 #include <linux/module.h>
  80 #include <linux/slab.h>
  81 #include <linux/vmalloc.h>
  82 #include <linux/miscdevice.h>
  83 #include <linux/spinlock.h>
  84 #include <linux/mm.h>
  85 #include <linux/fs.h>
  86 #include <linux/mutex.h>
  87 #include <linux/cpu.h>
  88 #include <linux/firmware.h>
  89 #include <linux/platform_device.h>
  90
  91 #include <asm/msr.h>
  92 #include <asm/uaccess.h>
  93 #include <asm/processor.h>
  94 #include <asm/microcode.h>
  95
  96 MODULE_DESCRIPTION("Microcode Update Driver");
  97 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
  98 MODULE_LICENSE("GPL");
  99
 100 struct microcode_header_intel {
 101         unsigned int            hdrver;
 102         unsigned int            rev;
 103         unsigned int            date;
 104         unsigned int            sig;
 105         unsigned int            cksum;
 106         unsigned int            ldrver;
 107         unsigned int            pf;
 108         unsigned int            datasize;
 109         unsigned int            totalsize;
 110         unsigned int            reserved[3];
 111 };
 112
 113 struct microcode_intel {
 114         struct microcode_header_intel hdr;
 115         unsigned int            bits[0];
 116 };
 117
 118 /* microcode format is extended from prescott processors */
 119 struct extended_signature {
 120         unsigned int            sig;
 121         unsigned int            pf;
 122         unsigned int            cksum;
 123 };
 124
 125 struct extended_sigtable {
 126         unsigned int            count;
 127         unsigned int            cksum;
 128         unsigned int            reserved[3];
 129         struct extended_signature sigs[0];
 130 };
 131
 132 #define DEFAULT_UCODE_DATASIZE  (2000)
 133 #define MC_HEADER_SIZE          (sizeof(struct microcode_header_intel))
 134 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
 135 #define EXT_HEADER_SIZE         (sizeof(struct extended_sigtable))
 136 #define EXT_SIGNATURE_SIZE      (sizeof(struct extended_signature))
 137 #define DWSIZE                  (sizeof(u32))
 138 #define get_totalsize(mc) \
 139         (((struct microcode_intel *)mc)->hdr.totalsize ? \
 140          ((struct microcode_intel *)mc)->hdr.totalsize : \
 141          DEFAULT_UCODE_TOTALSIZE)
 142
 143 #define get_datasize(mc) \
 144         (((struct microcode_intel *)mc)->hdr.datasize ? \
 145          ((struct microcode_intel *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
 146
 147 #define sigmatch(s1, s2, p1, p2) \
 148         (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
 149
 150 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
 151
 152 /* serialize access to the physical write to MSR 0x79 */
 153 static DEFINE_SPINLOCK(microcode_update_lock);
 154
 155 static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
 156 {
 157         struct cpuinfo_x86 *c = &cpu_data(cpu_num);
 158         unsigned int val[2];
 159
 160         memset(csig, 0, sizeof(*csig));
 161
 162         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
 163             cpu_has(c, X86_FEATURE_IA64)) {
 164                 printk(KERN_ERR "microcode: CPU%d not a capable Intel "
 165                         "processor\n", cpu_num);
 166                 return -1;
 167         }
 168
 169         csig->sig = cpuid_eax(0x00000001);
 170
 171         if ((c->x86_model >= 5) || (c->x86 > 6)) {
 172                 /* get processor flags from MSR 0x17 */
 173                 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
 174                 csig->pf = 1 << ((val[1] >> 18) & 7);
 175         }
 176
 177         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 178         /* see notes above for revision 1.07.  Apparent chip bug */
 179         sync_core();
 180         /* get the current revision from MSR 0x8B */
 181         rdmsr(MSR_IA32_UCODE_REV, val[0], csig->rev);
 182         pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
 183                         csig->sig, csig->pf, csig->rev);
 184
 185         return 0;
 186 }
 187
 188 static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
 189 {
 190         return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
 191 }
 192
 193 static inline int
 194 update_match_revision(struct microcode_header_intel *mc_header, int rev)
 195 {
 196         return (mc_header->rev <= rev) ? 0 : 1;
 197 }
 198
 199 static int microcode_sanity_check(void *mc)
 200 {
 201         struct microcode_header_intel *mc_header = mc;
 202         struct extended_sigtable *ext_header = NULL;
 203         struct extended_signature *ext_sig;
 204         unsigned long total_size, data_size, ext_table_size;
 205         int sum, orig_sum, ext_sigcount = 0, i;
 206
 207         total_size = get_totalsize(mc_header);
 208         data_size = get_datasize(mc_header);
 209         if (data_size + MC_HEADER_SIZE > total_size) {
 210                 printk(KERN_ERR "microcode: error! "
 211                         "Bad data size in microcode data file\n");
 212                 return -EINVAL;
 213         }
 214
 215         if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
 216                 printk(KERN_ERR "microcode: error! "
 217                         "Unknown microcode update format\n");
 218                 return -EINVAL;
 219         }
 220         ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
 221         if (ext_table_size) {
 222                 if ((ext_table_size < EXT_HEADER_SIZE)
 223                  || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
 224                         printk(KERN_ERR "microcode: error! "
 225                                 "Small exttable size in microcode data file\n");
 226                         return -EINVAL;
 227                 }
 228                 ext_header = mc + MC_HEADER_SIZE + data_size;
 229                 if (ext_table_size != exttable_size(ext_header)) {
 230                         printk(KERN_ERR "microcode: error! "
 231                                 "Bad exttable size in microcode data file\n");
 232                         return -EFAULT;
 233                 }
 234                 ext_sigcount = ext_header->count;
 235         }
 236
 237         /* check extended table checksum */
 238         if (ext_table_size) {
 239                 int ext_table_sum = 0;
 240                 int *ext_tablep = (int *)ext_header;
 241
 242                 i = ext_table_size / DWSIZE;
 243                 while (i--)
 244                         ext_table_sum += ext_tablep[i];
 245                 if (ext_table_sum) {
 246                         printk(KERN_WARNING "microcode: aborting, "
 247                                 "bad extended signature table checksum\n");
 248                         return -EINVAL;
 249                 }
 250         }
 251
 252         /* calculate the checksum */
 253         orig_sum = 0;
 254         i = (MC_HEADER_SIZE + data_size) / DWSIZE;
 255         while (i--)
 256                 orig_sum += ((int *)mc)[i];
 257         if (orig_sum) {
 258                 printk(KERN_ERR "microcode: aborting, bad checksum\n");
 259                 return -EINVAL;
 260         }
 261         if (!ext_table_size)
 262                 return 0;
 263         /* check extended signature checksum */
 264         for (i = 0; i < ext_sigcount; i++) {
 265                 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
 266                           EXT_SIGNATURE_SIZE * i;
 267                 sum = orig_sum
 268                         - (mc_header->sig + mc_header->pf + mc_header->cksum)
 269                         + (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
 270                 if (sum) {
 271                         printk(KERN_ERR "microcode: aborting, bad checksum\n");
 272                         return -EINVAL;
 273                 }
 274         }
 275         return 0;
 276 }
 277
 278 /*
 279  * return 0 - no update found
 280  * return 1 - found update
 281  */
 282 static int
 283 get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
 284 {
 285         struct microcode_header_intel *mc_header = mc;
 286         struct extended_sigtable *ext_header;
 287         unsigned long total_size = get_totalsize(mc_header);
 288         int ext_sigcount, i;
 289         struct extended_signature *ext_sig;
 290
 291         if (!update_match_revision(mc_header, rev))
 292                 return 0;
 293
 294         if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
 295                 return 1;
 296
 297         /* Look for ext. headers: */
 298         if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
 299                 return 0;
 300
 301         ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
 302         ext_sigcount = ext_header->count;
 303         ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
 304
 305         for (i = 0; i < ext_sigcount; i++) {
 306                 if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
 307                         return 1;
 308                 ext_sig++;
 309         }
 310         return 0;
 311 }
 312
 313 static void apply_microcode(int cpu)
 314 {
 315         unsigned long flags;
 316         unsigned int val[2];
 317         int cpu_num = raw_smp_processor_id();
 318         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 319         struct microcode_intel *mc_intel = uci->mc;
 320
 321         /* We should bind the task to the CPU */
 322         BUG_ON(cpu_num != cpu);
 323
 324         if (mc_intel == NULL)
 325                 return;
 326
 327         /* serialize access to the physical write to MSR 0x79 */
 328         spin_lock_irqsave(&microcode_update_lock, flags);
 329
 330         /* write microcode via MSR 0x79 */
 331         wrmsr(MSR_IA32_UCODE_WRITE,
 332               (unsigned long) mc_intel->bits,
 333               (unsigned long) mc_intel->bits >> 16 >> 16);
 334         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
 335
 336         /* see notes above for revision 1.07.  Apparent chip bug */
 337         sync_core();
 338
 339         /* get the current revision from MSR 0x8B */
 340         rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
 341
 342         spin_unlock_irqrestore(&microcode_update_lock, flags);
 343         if (val[1] != mc_intel->hdr.rev) {
 344                 printk(KERN_ERR "microcode: CPU%d update from revision "
 345                         "0x%x to 0x%x failed\n", cpu_num, uci->cpu_sig.rev, val[1]);
 346                 return;
 347         }
 348         printk(KERN_INFO "microcode: CPU%d updated from revision "
 349                "0x%x to 0x%x, date = %04x-%02x-%02x \n",
 350                 cpu_num, uci->cpu_sig.rev, val[1],
 351                 mc_intel->hdr.date & 0xffff,
 352                 mc_intel->hdr.date >> 24,
 353                 (mc_intel->hdr.date >> 16) & 0xff);
 354         uci->cpu_sig.rev = val[1];
 355 }
 356
 357 static int generic_load_microcode(int cpu, void *data, size_t size,
 358                 int (*get_ucode_data)(void *, const void *, size_t))
 359 {
 360         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 361         u8 *ucode_ptr = data, *new_mc = NULL, *mc;
 362         int new_rev = uci->cpu_sig.rev;
 363         unsigned int leftover = size;
 364
 365         while (leftover) {
 366                 struct microcode_header_intel mc_header;
 367                 unsigned int mc_size;
 368
 369                 if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
 370                         break;
 371
 372                 mc_size = get_totalsize(&mc_header);
 373                 if (!mc_size || mc_size > leftover) {
 374                         printk(KERN_ERR "microcode: error!"
 375                                         "Bad data in microcode data file\n");
 376                         break;
 377                 }
 378
 379                 mc = vmalloc(mc_size);
 380                 if (!mc)
 381                         break;
 382
 383                 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
 384                     microcode_sanity_check(mc) < 0) {
 385                         vfree(mc);
 386                         break;
 387                 }
 388
 389                 if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
 390                         if (new_mc)
 391                                 vfree(new_mc);
 392                         new_rev = mc_header.rev;
 393                         new_mc  = mc;
 394                 } else
 395                         vfree(mc);
 396
 397                 ucode_ptr += mc_size;
 398                 leftover  -= mc_size;
 399         }
 400
 401         if (new_mc) {
 402                 if (!leftover) {
 403                         if (uci->mc)
 404                                 vfree(uci->mc);
 405                         uci->mc = (struct microcode_intel *)new_mc;
 406                         pr_debug("microcode: CPU%d found a matching microcode update with"
 407                                  " version 0x%x (current=0x%x)\n",
 408                                 cpu, new_rev, uci->cpu_sig.rev);
 409                 } else
 410                         vfree(new_mc);
 411         }
 412
 413         return (int)leftover;
 414 }
 415
 416 static int get_ucode_fw(void *to, const void *from, size_t n)
 417 {
 418         memcpy(to, from, n);
 419         return 0;
 420 }
 421
 422 static int request_microcode_fw(int cpu, struct device *device)
 423 {
 424         char name[30];
 425         struct cpuinfo_x86 *c = &cpu_data(cpu);
 426         const struct firmware *firmware;
 427         int ret;
 428
 429         /* We should bind the task to the CPU */
 430         BUG_ON(cpu != raw_smp_processor_id());
 431         sprintf(name, "intel-ucode/%02x-%02x-%02x",
 432                 c->x86, c->x86_model, c->x86_mask);
 433         ret = request_firmware(&firmware, name, device);
 434         if (ret) {
 435                 pr_debug("microcode: data file %s load failed\n", name);
 436                 return ret;
 437         }
 438
 439         ret = generic_load_microcode(cpu, (void*)firmware->data, firmware->size,
 440                         &get_ucode_fw);
 441
 442         release_firmware(firmware);
 443
 444         return ret;
 445 }
 446
 447 static int get_ucode_user(void *to, const void *from, size_t n)
 448 {
 449         return copy_from_user(to, from, n);
 450 }
 451
 452 static int request_microcode_user(int cpu, const void __user *buf, size_t size)
 453 {
 454         /* We should bind the task to the CPU */
 455         BUG_ON(cpu != raw_smp_processor_id());
 456
 457         return generic_load_microcode(cpu, (void*)buf, size, &get_ucode_user);
 458 }
 459
 460 static void microcode_fini_cpu(int cpu)
 461 {
 462         struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
 463
 464         vfree(uci->mc);
 465         uci->mc = NULL;
 466 }
 467
 468 struct microcode_ops microcode_intel_ops = {
 469         .request_microcode_user           = request_microcode_user,
 470         .request_microcode_fw             = request_microcode_fw,
 471         .collect_cpu_info                 = collect_cpu_info,
 472         .apply_microcode                  = apply_microcode,
 473         .microcode_fini_cpu               = microcode_fini_cpu,
 474 };
 475
 476 struct microcode_ops * __init init_intel_microcode(void)
 477 {
 478         return &microcode_intel_ops;
 479 }
 480