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 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
update_match_cpu(struct cpu_signature * csig,int sig,int pf)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
update_match_revision(struct microcode_header_intel * mc_header,int rev)177 update_match_revision(struct microcode_header_intel *mc_header, int rev)
178 {
179 return (mc_header->rev <= rev) ? 0 : 1;
180 }
181
microcode_sanity_check(void * mc)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
get_matching_microcode(struct cpu_signature * cpu_sig,void * mc,int rev)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
apply_microcode(int cpu)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
generic_load_microcode(int cpu,void * data,size_t size,int (* get_ucode_data)(void *,const void *,size_t))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
get_ucode_fw(void * to,const void * from,size_t n)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
request_microcode_fw(int cpu,struct device * device)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
get_ucode_user(void * to,const void * from,size_t n)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
request_microcode_user(int cpu,const void __user * buf,size_t size)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
microcode_fini_cpu(int cpu)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
init_intel_microcode(void)464 struct microcode_ops * __init init_intel_microcode(void)
465 {
466 return µcode_intel_ops;
467 }
468
469