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
collect_cpu_info(int cpu_num,struct cpu_signature * csig)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 csig->sig = cpuid_eax(0x00000001);
151
152 if ((c->x86_model >= 5) || (c->x86 > 6)) {
153 /* get processor flags from MSR 0x17 */
154 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
155 csig->pf = 1 << ((val[1] >> 18) & 7);
156 }
157
158 csig->rev = c->microcode;
159 pr_info("CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n",
160 cpu_num, csig->sig, csig->pf, csig->rev);
161
162 return 0;
163 }
164
update_match_cpu(struct cpu_signature * csig,int sig,int pf)165 static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
166 {
167 return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
168 }
169
170 static inline int
update_match_revision(struct microcode_header_intel * mc_header,int rev)171 update_match_revision(struct microcode_header_intel *mc_header, int rev)
172 {
173 return (mc_header->rev <= rev) ? 0 : 1;
174 }
175
microcode_sanity_check(void * mc)176 static int microcode_sanity_check(void *mc)
177 {
178 unsigned long total_size, data_size, ext_table_size;
179 struct microcode_header_intel *mc_header = mc;
180 struct extended_sigtable *ext_header = NULL;
181 int sum, orig_sum, ext_sigcount = 0, i;
182 struct extended_signature *ext_sig;
183
184 total_size = get_totalsize(mc_header);
185 data_size = get_datasize(mc_header);
186
187 if (data_size + MC_HEADER_SIZE > total_size) {
188 pr_err("error! Bad data size in microcode data file\n");
189 return -EINVAL;
190 }
191
192 if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
193 pr_err("error! Unknown microcode update format\n");
194 return -EINVAL;
195 }
196 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
197 if (ext_table_size) {
198 if ((ext_table_size < EXT_HEADER_SIZE)
199 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
200 pr_err("error! Small exttable size in microcode data file\n");
201 return -EINVAL;
202 }
203 ext_header = mc + MC_HEADER_SIZE + data_size;
204 if (ext_table_size != exttable_size(ext_header)) {
205 pr_err("error! Bad exttable size in microcode data file\n");
206 return -EFAULT;
207 }
208 ext_sigcount = ext_header->count;
209 }
210
211 /* check extended table checksum */
212 if (ext_table_size) {
213 int ext_table_sum = 0;
214 int *ext_tablep = (int *)ext_header;
215
216 i = ext_table_size / DWSIZE;
217 while (i--)
218 ext_table_sum += ext_tablep[i];
219 if (ext_table_sum) {
220 pr_warning("aborting, bad extended signature table checksum\n");
221 return -EINVAL;
222 }
223 }
224
225 /* calculate the checksum */
226 orig_sum = 0;
227 i = (MC_HEADER_SIZE + data_size) / DWSIZE;
228 while (i--)
229 orig_sum += ((int *)mc)[i];
230 if (orig_sum) {
231 pr_err("aborting, bad checksum\n");
232 return -EINVAL;
233 }
234 if (!ext_table_size)
235 return 0;
236 /* check extended signature checksum */
237 for (i = 0; i < ext_sigcount; i++) {
238 ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
239 EXT_SIGNATURE_SIZE * i;
240 sum = orig_sum
241 - (mc_header->sig + mc_header->pf + mc_header->cksum)
242 + (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
243 if (sum) {
244 pr_err("aborting, bad checksum\n");
245 return -EINVAL;
246 }
247 }
248 return 0;
249 }
250
251 /*
252 * return 0 - no update found
253 * return 1 - found update
254 */
255 static int
get_matching_microcode(struct cpu_signature * cpu_sig,void * mc,int rev)256 get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
257 {
258 struct microcode_header_intel *mc_header = mc;
259 struct extended_sigtable *ext_header;
260 unsigned long total_size = get_totalsize(mc_header);
261 int ext_sigcount, i;
262 struct extended_signature *ext_sig;
263
264 if (!update_match_revision(mc_header, rev))
265 return 0;
266
267 if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
268 return 1;
269
270 /* Look for ext. headers: */
271 if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
272 return 0;
273
274 ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
275 ext_sigcount = ext_header->count;
276 ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
277
278 for (i = 0; i < ext_sigcount; i++) {
279 if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
280 return 1;
281 ext_sig++;
282 }
283 return 0;
284 }
285
apply_microcode(int cpu)286 static int apply_microcode(int cpu)
287 {
288 struct microcode_intel *mc_intel;
289 struct ucode_cpu_info *uci;
290 unsigned int val[2];
291 int cpu_num = raw_smp_processor_id();
292 struct cpuinfo_x86 *c = &cpu_data(cpu_num);
293
294 uci = ucode_cpu_info + cpu;
295 mc_intel = uci->mc;
296
297 /* We should bind the task to the CPU */
298 BUG_ON(cpu_num != cpu);
299
300 if (mc_intel == NULL)
301 return 0;
302
303 /* write microcode via MSR 0x79 */
304 wrmsr(MSR_IA32_UCODE_WRITE,
305 (unsigned long) mc_intel->bits,
306 (unsigned long) mc_intel->bits >> 16 >> 16);
307 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
308
309 /* As documented in the SDM: Do a CPUID 1 here */
310 sync_core();
311
312 /* get the current revision from MSR 0x8B */
313 rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
314
315 if (val[1] != mc_intel->hdr.rev) {
316 pr_err("CPU%d update to revision 0x%x failed\n",
317 cpu_num, mc_intel->hdr.rev);
318 return -1;
319 }
320 pr_info("CPU%d updated to revision 0x%x, date = %04x-%02x-%02x\n",
321 cpu_num, val[1],
322 mc_intel->hdr.date & 0xffff,
323 mc_intel->hdr.date >> 24,
324 (mc_intel->hdr.date >> 16) & 0xff);
325
326 uci->cpu_sig.rev = val[1];
327 c->microcode = val[1];
328
329 return 0;
330 }
331
generic_load_microcode(int cpu,void * data,size_t size,int (* get_ucode_data)(void *,const void *,size_t))332 static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
333 int (*get_ucode_data)(void *, const void *, size_t))
334 {
335 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
336 u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
337 int new_rev = uci->cpu_sig.rev;
338 unsigned int leftover = size;
339 enum ucode_state state = UCODE_OK;
340 unsigned int curr_mc_size = 0;
341
342 while (leftover) {
343 struct microcode_header_intel mc_header;
344 unsigned int mc_size;
345
346 if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
347 break;
348
349 mc_size = get_totalsize(&mc_header);
350 if (!mc_size || mc_size > leftover) {
351 pr_err("error! Bad data in microcode data file\n");
352 break;
353 }
354
355 /* For performance reasons, reuse mc area when possible */
356 if (!mc || mc_size > curr_mc_size) {
357 vfree(mc);
358 mc = vmalloc(mc_size);
359 if (!mc)
360 break;
361 curr_mc_size = mc_size;
362 }
363
364 if (get_ucode_data(mc, ucode_ptr, mc_size) ||
365 microcode_sanity_check(mc) < 0) {
366 break;
367 }
368
369 if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
370 vfree(new_mc);
371 new_rev = mc_header.rev;
372 new_mc = mc;
373 mc = NULL; /* trigger new vmalloc */
374 }
375
376 ucode_ptr += mc_size;
377 leftover -= mc_size;
378 }
379
380 vfree(mc);
381
382 if (leftover) {
383 vfree(new_mc);
384 state = UCODE_ERROR;
385 goto out;
386 }
387
388 if (!new_mc) {
389 state = UCODE_NFOUND;
390 goto out;
391 }
392
393 vfree(uci->mc);
394 uci->mc = (struct microcode_intel *)new_mc;
395
396 pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
397 cpu, new_rev, uci->cpu_sig.rev);
398 out:
399 return state;
400 }
401
get_ucode_fw(void * to,const void * from,size_t n)402 static int get_ucode_fw(void *to, const void *from, size_t n)
403 {
404 memcpy(to, from, n);
405 return 0;
406 }
407
request_microcode_fw(int cpu,struct device * device)408 static enum ucode_state request_microcode_fw(int cpu, struct device *device)
409 {
410 char name[30];
411 struct cpuinfo_x86 *c = &cpu_data(cpu);
412 const struct firmware *firmware;
413 enum ucode_state ret;
414
415 sprintf(name, "intel-ucode/%02x-%02x-%02x",
416 c->x86, c->x86_model, c->x86_mask);
417
418 if (request_firmware(&firmware, name, device)) {
419 pr_debug("data file %s load failed\n", name);
420 return UCODE_NFOUND;
421 }
422
423 ret = generic_load_microcode(cpu, (void *)firmware->data,
424 firmware->size, &get_ucode_fw);
425
426 release_firmware(firmware);
427
428 return ret;
429 }
430
get_ucode_user(void * to,const void * from,size_t n)431 static int get_ucode_user(void *to, const void *from, size_t n)
432 {
433 return copy_from_user(to, from, n);
434 }
435
436 static enum ucode_state
request_microcode_user(int cpu,const void __user * buf,size_t size)437 request_microcode_user(int cpu, const void __user *buf, size_t size)
438 {
439 return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
440 }
441
microcode_fini_cpu(int cpu)442 static void microcode_fini_cpu(int cpu)
443 {
444 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
445
446 vfree(uci->mc);
447 uci->mc = NULL;
448 }
449
450 static struct microcode_ops microcode_intel_ops = {
451 .request_microcode_user = request_microcode_user,
452 .request_microcode_fw = request_microcode_fw,
453 .collect_cpu_info = collect_cpu_info,
454 .apply_microcode = apply_microcode,
455 .microcode_fini_cpu = microcode_fini_cpu,
456 };
457
init_intel_microcode(void)458 struct microcode_ops * __init init_intel_microcode(void)
459 {
460 struct cpuinfo_x86 *c = &cpu_data(0);
461
462 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
463 cpu_has(c, X86_FEATURE_IA64)) {
464 pr_err("Intel CPU family 0x%x not supported\n", c->x86);
465 return NULL;
466 }
467
468 return µcode_intel_ops;
469 }
470
471