aboutsummaryrefslogtreecommitdiffstats
path: root/arch/i386/kernel/microcode.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/microcode.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/i386/kernel/microcode.c')
-rw-r--r--arch/i386/kernel/microcode.c512
1 files changed, 512 insertions, 0 deletions
diff --git a/arch/i386/kernel/microcode.c b/arch/i386/kernel/microcode.c
new file mode 100644
index 000000000000..a77c612aad00
--- /dev/null
+++ b/arch/i386/kernel/microcode.c
@@ -0,0 +1,512 @@
1/*
2 * Intel CPU Microcode Update Driver for Linux
3 *
4 * Copyright (C) 2000-2004 Tigran Aivazian
5 *
6 * This driver allows to upgrade microcode on Intel processors
7 * belonging to IA-32 family - PentiumPro, Pentium II,
8 * Pentium III, Xeon, Pentium 4, etc.
9 *
10 * Reference: Section 8.10 of Volume III, Intel Pentium 4 Manual,
11 * Order Number 245472 or free download from:
12 *
13 * http://developer.intel.com/design/pentium4/manuals/245472.htm
14 *
15 * For more information, go to http://www.urbanmyth.org/microcode
16 *
17 * This program is free software; you can redistribute it and/or
18 * modify it under the terms of the GNU General Public License
19 * as published by the Free Software Foundation; either version
20 * 2 of the License, or (at your option) any later version.
21 *
22 * 1.0 16 Feb 2000, Tigran Aivazian <tigran@sco.com>
23 * Initial release.
24 * 1.01 18 Feb 2000, Tigran Aivazian <tigran@sco.com>
25 * Added read() support + cleanups.
26 * 1.02 21 Feb 2000, Tigran Aivazian <tigran@sco.com>
27 * Added 'device trimming' support. open(O_WRONLY) zeroes
28 * and frees the saved copy of applied microcode.
29 * 1.03 29 Feb 2000, Tigran Aivazian <tigran@sco.com>
30 * Made to use devfs (/dev/cpu/microcode) + cleanups.
31 * 1.04 06 Jun 2000, Simon Trimmer <simon@veritas.com>
32 * Added misc device support (now uses both devfs and misc).
33 * Added MICROCODE_IOCFREE ioctl to clear memory.
34 * 1.05 09 Jun 2000, Simon Trimmer <simon@veritas.com>
35 * Messages for error cases (non Intel & no suitable microcode).
36 * 1.06 03 Aug 2000, Tigran Aivazian <tigran@veritas.com>
37 * Removed ->release(). Removed exclusive open and status bitmap.
38 * Added microcode_rwsem to serialize read()/write()/ioctl().
39 * Removed global kernel lock usage.
40 * 1.07 07 Sep 2000, Tigran Aivazian <tigran@veritas.com>
41 * Write 0 to 0x8B msr and then cpuid before reading revision,
42 * so that it works even if there were no update done by the
43 * BIOS. Otherwise, reading from 0x8B gives junk (which happened
44 * to be 0 on my machine which is why it worked even when I
45 * disabled update by the BIOS)
46 * Thanks to Eric W. Biederman <ebiederman@lnxi.com> for the fix.
47 * 1.08 11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and
48 * Tigran Aivazian <tigran@veritas.com>
49 * Intel Pentium 4 processor support and bugfixes.
50 * 1.09 30 Oct 2001, Tigran Aivazian <tigran@veritas.com>
51 * Bugfix for HT (Hyper-Threading) enabled processors
52 * whereby processor resources are shared by all logical processors
53 * in a single CPU package.
54 * 1.10 28 Feb 2002 Asit K Mallick <asit.k.mallick@intel.com> and
55 * Tigran Aivazian <tigran@veritas.com>,
56 * Serialize updates as required on HT processors due to speculative
57 * nature of implementation.
58 * 1.11 22 Mar 2002 Tigran Aivazian <tigran@veritas.com>
59 * Fix the panic when writing zero-length microcode chunk.
60 * 1.12 29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>,
61 * Jun Nakajima <jun.nakajima@intel.com>
62 * Support for the microcode updates in the new format.
63 * 1.13 10 Oct 2003 Tigran Aivazian <tigran@veritas.com>
64 * Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl
65 * because we no longer hold a copy of applied microcode
66 * in kernel memory.
67 * 1.14 25 Jun 2004 Tigran Aivazian <tigran@veritas.com>
68 * Fix sigmatch() macro to handle old CPUs with pf == 0.
69 * Thanks to Stuart Swales for pointing out this bug.
70 */
71
72//#define DEBUG /* pr_debug */
73#include <linux/kernel.h>
74#include <linux/init.h>
75#include <linux/sched.h>
76#include <linux/module.h>
77#include <linux/slab.h>
78#include <linux/vmalloc.h>
79#include <linux/miscdevice.h>
80#include <linux/spinlock.h>
81#include <linux/mm.h>
82
83#include <asm/msr.h>
84#include <asm/uaccess.h>
85#include <asm/processor.h>
86
87MODULE_DESCRIPTION("Intel CPU (IA-32) Microcode Update Driver");
88MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
89MODULE_LICENSE("GPL");
90
91#define MICROCODE_VERSION "1.14"
92
93#define DEFAULT_UCODE_DATASIZE (2000) /* 2000 bytes */
94#define MC_HEADER_SIZE (sizeof (microcode_header_t)) /* 48 bytes */
95#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
96#define EXT_HEADER_SIZE (sizeof (struct extended_sigtable)) /* 20 bytes */
97#define EXT_SIGNATURE_SIZE (sizeof (struct extended_signature)) /* 12 bytes */
98#define DWSIZE (sizeof (u32))
99#define get_totalsize(mc) \
100 (((microcode_t *)mc)->hdr.totalsize ? \
101 ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
102#define get_datasize(mc) \
103 (((microcode_t *)mc)->hdr.datasize ? \
104 ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
105
106#define sigmatch(s1, s2, p1, p2) \
107 (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
108
109#define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
110
111/* serialize access to the physical write to MSR 0x79 */
112static DEFINE_SPINLOCK(microcode_update_lock);
113
114/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
115static DECLARE_MUTEX(microcode_sem);
116
117static void __user *user_buffer; /* user area microcode data buffer */
118static unsigned int user_buffer_size; /* it's size */
119
120typedef enum mc_error_code {
121 MC_SUCCESS = 0,
122 MC_NOTFOUND = 1,
123 MC_MARKED = 2,
124 MC_ALLOCATED = 3,
125} mc_error_code_t;
126
127static struct ucode_cpu_info {
128 unsigned int sig;
129 unsigned int pf;
130 unsigned int rev;
131 unsigned int cksum;
132 mc_error_code_t err;
133 microcode_t *mc;
134} ucode_cpu_info[NR_CPUS];
135
136static int microcode_open (struct inode *unused1, struct file *unused2)
137{
138 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
139}
140
141static void collect_cpu_info (void *unused)
142{
143 int cpu_num = smp_processor_id();
144 struct cpuinfo_x86 *c = cpu_data + cpu_num;
145 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
146 unsigned int val[2];
147
148 uci->sig = uci->pf = uci->rev = uci->cksum = 0;
149 uci->err = MC_NOTFOUND;
150 uci->mc = NULL;
151
152 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
153 cpu_has(c, X86_FEATURE_IA64)) {
154 printk(KERN_ERR "microcode: CPU%d not a capable Intel processor\n", cpu_num);
155 return;
156 } else {
157 uci->sig = cpuid_eax(0x00000001);
158
159 if ((c->x86_model >= 5) || (c->x86 > 6)) {
160 /* get processor flags from MSR 0x17 */
161 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
162 uci->pf = 1 << ((val[1] >> 18) & 7);
163 }
164 }
165
166 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
167 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
168 /* get the current revision from MSR 0x8B */
169 rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
170 pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
171 uci->sig, uci->pf, uci->rev);
172}
173
174static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
175{
176 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
177
178 pr_debug("Microcode Found.\n");
179 pr_debug(" Header Revision 0x%x\n", mc_header->hdrver);
180 pr_debug(" Loader Revision 0x%x\n", mc_header->ldrver);
181 pr_debug(" Revision 0x%x \n", mc_header->rev);
182 pr_debug(" Date %x/%x/%x\n",
183 ((mc_header->date >> 24 ) & 0xff),
184 ((mc_header->date >> 16 ) & 0xff),
185 (mc_header->date & 0xFFFF));
186 pr_debug(" Signature 0x%x\n", sig);
187 pr_debug(" Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
188 ((sig >> 12) & 0x3),
189 ((sig >> 8) & 0xf),
190 ((sig >> 4) & 0xf),
191 ((sig & 0xf)));
192 pr_debug(" Processor Flags 0x%x\n", pf);
193 pr_debug(" Checksum 0x%x\n", cksum);
194
195 if (mc_header->rev < uci->rev) {
196 printk(KERN_ERR "microcode: CPU%d not 'upgrading' to earlier revision"
197 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
198 goto out;
199 } else if (mc_header->rev == uci->rev) {
200 /* notify the caller of success on this cpu */
201 uci->err = MC_SUCCESS;
202 printk(KERN_ERR "microcode: CPU%d already at revision"
203 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
204 goto out;
205 }
206
207 pr_debug("microcode: CPU%d found a matching microcode update with "
208 " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
209 uci->cksum = cksum;
210 uci->pf = pf; /* keep the original mc pf for cksum calculation */
211 uci->err = MC_MARKED; /* found the match */
212out:
213 return;
214}
215
216static int find_matching_ucodes (void)
217{
218 int cursor = 0;
219 int error = 0;
220
221 while (cursor + MC_HEADER_SIZE < user_buffer_size) {
222 microcode_header_t mc_header;
223 void *newmc = NULL;
224 int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
225
226 if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
227 printk(KERN_ERR "microcode: error! Can not read user data\n");
228 error = -EFAULT;
229 goto out;
230 }
231
232 total_size = get_totalsize(&mc_header);
233 if ((cursor + total_size > user_buffer_size) || (total_size < DEFAULT_UCODE_TOTALSIZE)) {
234 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
235 error = -EINVAL;
236 goto out;
237 }
238
239 data_size = get_datasize(&mc_header);
240 if ((data_size + MC_HEADER_SIZE > total_size) || (data_size < DEFAULT_UCODE_DATASIZE)) {
241 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
242 error = -EINVAL;
243 goto out;
244 }
245
246 if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
247 printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
248 error = -EINVAL;
249 goto out;
250 }
251
252 for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
253 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
254 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
255 continue;
256
257 if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->pf))
258 mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
259 }
260
261 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
262 if (ext_table_size) {
263 struct extended_sigtable ext_header;
264 struct extended_signature ext_sig;
265 int ext_sigcount;
266
267 if ((ext_table_size < EXT_HEADER_SIZE)
268 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
269 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
270 error = -EINVAL;
271 goto out;
272 }
273 if (copy_from_user(&ext_header, user_buffer + cursor
274 + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
275 printk(KERN_ERR "microcode: error! Can not read user data\n");
276 error = -EFAULT;
277 goto out;
278 }
279 if (ext_table_size != exttable_size(&ext_header)) {
280 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
281 error = -EFAULT;
282 goto out;
283 }
284
285 ext_sigcount = ext_header.count;
286
287 for (i = 0; i < ext_sigcount; i++) {
288 if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE
289 + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
290 printk(KERN_ERR "microcode: error! Can not read user data\n");
291 error = -EFAULT;
292 goto out;
293 }
294 for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
295 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
296 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
297 continue;
298 if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->pf)) {
299 mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
300 }
301 }
302 }
303 }
304 /* now check if any cpu has matched */
305 for (cpu_num = 0, allocated_flag = 0, sum = 0; cpu_num < num_online_cpus(); cpu_num++) {
306 if (ucode_cpu_info[cpu_num].err == MC_MARKED) {
307 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
308 if (!allocated_flag) {
309 allocated_flag = 1;
310 newmc = vmalloc(total_size);
311 if (!newmc) {
312 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
313 error = -ENOMEM;
314 goto out;
315 }
316 if (copy_from_user(newmc + MC_HEADER_SIZE,
317 user_buffer + cursor + MC_HEADER_SIZE,
318 total_size - MC_HEADER_SIZE)) {
319 printk(KERN_ERR "microcode: error! Can not read user data\n");
320 vfree(newmc);
321 error = -EFAULT;
322 goto out;
323 }
324 memcpy(newmc, &mc_header, MC_HEADER_SIZE);
325 /* check extended table checksum */
326 if (ext_table_size) {
327 int ext_table_sum = 0;
328 int * ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
329 i = ext_table_size / DWSIZE;
330 while (i--) ext_table_sum += ext_tablep[i];
331 if (ext_table_sum) {
332 printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
333 vfree(newmc);
334 error = -EINVAL;
335 goto out;
336 }
337 }
338
339 /* calculate the checksum */
340 i = (MC_HEADER_SIZE + data_size) / DWSIZE;
341 while (i--) sum += ((int *)newmc)[i];
342 sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
343 }
344 ucode_cpu_info[cpu_num].mc = newmc;
345 ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
346 if (sum + uci->sig + uci->pf + uci->cksum != 0) {
347 printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
348 error = -EINVAL;
349 goto out;
350 }
351 }
352 }
353 cursor += total_size; /* goto the next update patch */
354 } /* end of while */
355out:
356 return error;
357}
358
359static void do_update_one (void * unused)
360{
361 unsigned long flags;
362 unsigned int val[2];
363 int cpu_num = smp_processor_id();
364 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
365
366 if (uci->mc == NULL) {
367 printk(KERN_INFO "microcode: No new microcode data for CPU%d\n", cpu_num);
368 return;
369 }
370
371 /* serialize access to the physical write to MSR 0x79 */
372 spin_lock_irqsave(&microcode_update_lock, flags);
373
374 /* write microcode via MSR 0x79 */
375 wrmsr(MSR_IA32_UCODE_WRITE,
376 (unsigned long) uci->mc->bits,
377 (unsigned long) uci->mc->bits >> 16 >> 16);
378 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
379
380 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
381 /* get the current revision from MSR 0x8B */
382 rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
383
384 /* notify the caller of success on this cpu */
385 uci->err = MC_SUCCESS;
386 spin_unlock_irqrestore(&microcode_update_lock, flags);
387 printk(KERN_INFO "microcode: CPU%d updated from revision "
388 "0x%x to 0x%x, date = %08x \n",
389 cpu_num, uci->rev, val[1], uci->mc->hdr.date);
390 return;
391}
392
393static int do_microcode_update (void)
394{
395 int i, error;
396
397 if (on_each_cpu(collect_cpu_info, NULL, 1, 1) != 0) {
398 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
399 error = -EIO;
400 goto out;
401 }
402
403 if ((error = find_matching_ucodes())) {
404 printk(KERN_ERR "microcode: Error in the microcode data\n");
405 goto out_free;
406 }
407
408 if (on_each_cpu(do_update_one, NULL, 1, 1) != 0) {
409 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
410 error = -EIO;
411 }
412
413out_free:
414 for (i = 0; i < num_online_cpus(); i++) {
415 if (ucode_cpu_info[i].mc) {
416 int j;
417 void *tmp = ucode_cpu_info[i].mc;
418 vfree(tmp);
419 for (j = i; j < num_online_cpus(); j++) {
420 if (ucode_cpu_info[j].mc == tmp)
421 ucode_cpu_info[j].mc = NULL;
422 }
423 }
424 }
425out:
426 return error;
427}
428
429static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
430{
431 ssize_t ret;
432
433 if (len < DEFAULT_UCODE_TOTALSIZE) {
434 printk(KERN_ERR "microcode: not enough data\n");
435 return -EINVAL;
436 }
437
438 if ((len >> PAGE_SHIFT) > num_physpages) {
439 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
440 return -EINVAL;
441 }
442
443 down(&microcode_sem);
444
445 user_buffer = (void __user *) buf;
446 user_buffer_size = (int) len;
447
448 ret = do_microcode_update();
449 if (!ret)
450 ret = (ssize_t)len;
451
452 up(&microcode_sem);
453
454 return ret;
455}
456
457static int microcode_ioctl (struct inode *inode, struct file *file,
458 unsigned int cmd, unsigned long arg)
459{
460 switch (cmd) {
461 /*
462 * XXX: will be removed after microcode_ctl
463 * is updated to ignore failure of this ioctl()
464 */
465 case MICROCODE_IOCFREE:
466 return 0;
467 default:
468 return -EINVAL;
469 }
470 return -EINVAL;
471}
472
473static struct file_operations microcode_fops = {
474 .owner = THIS_MODULE,
475 .write = microcode_write,
476 .ioctl = microcode_ioctl,
477 .open = microcode_open,
478};
479
480static struct miscdevice microcode_dev = {
481 .minor = MICROCODE_MINOR,
482 .name = "microcode",
483 .devfs_name = "cpu/microcode",
484 .fops = &microcode_fops,
485};
486
487static int __init microcode_init (void)
488{
489 int error;
490
491 error = misc_register(&microcode_dev);
492 if (error) {
493 printk(KERN_ERR
494 "microcode: can't misc_register on minor=%d\n",
495 MICROCODE_MINOR);
496 return error;
497 }
498
499 printk(KERN_INFO
500 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
501 return 0;
502}
503
504static void __exit microcode_exit (void)
505{
506 misc_deregister(&microcode_dev);
507 printk(KERN_INFO "IA-32 Microcode Update Driver v" MICROCODE_VERSION " unregistered\n");
508}
509
510module_init(microcode_init)
511module_exit(microcode_exit)
512MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);