Merge git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6
[linux-2.6] / arch / i386 / kernel / microcode.c
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/capability.h>
74 #include <linux/kernel.h>
75 #include <linux/init.h>
76 #include <linux/sched.h>
77 #include <linux/cpumask.h>
78 #include <linux/module.h>
79 #include <linux/slab.h>
80 #include <linux/vmalloc.h>
81 #include <linux/miscdevice.h>
82 #include <linux/spinlock.h>
83 #include <linux/mm.h>
84 #include <linux/mutex.h>
85
86 #include <asm/msr.h>
87 #include <asm/uaccess.h>
88 #include <asm/processor.h>
89
90 MODULE_DESCRIPTION("Intel CPU (IA-32) Microcode Update Driver");
91 MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
92 MODULE_LICENSE("GPL");
93
94 static int verbose;
95 module_param(verbose, int, 0644);
96
97 #define MICROCODE_VERSION       "1.14a"
98
99 #define DEFAULT_UCODE_DATASIZE  (2000)    /* 2000 bytes */
100 #define MC_HEADER_SIZE          (sizeof (microcode_header_t))     /* 48 bytes */
101 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
102 #define EXT_HEADER_SIZE         (sizeof (struct extended_sigtable)) /* 20 bytes */
103 #define EXT_SIGNATURE_SIZE      (sizeof (struct extended_signature)) /* 12 bytes */
104 #define DWSIZE                  (sizeof (u32))
105 #define get_totalsize(mc) \
106         (((microcode_t *)mc)->hdr.totalsize ? \
107          ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
108 #define get_datasize(mc) \
109         (((microcode_t *)mc)->hdr.datasize ? \
110          ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
111
112 #define sigmatch(s1, s2, p1, p2) \
113         (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
114
115 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
116
117 /* serialize access to the physical write to MSR 0x79 */
118 static DEFINE_SPINLOCK(microcode_update_lock);
119
120 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
121 static DEFINE_MUTEX(microcode_mutex);
122
123 static void __user *user_buffer;        /* user area microcode data buffer */
124 static unsigned int user_buffer_size;   /* it's size */
125
126 typedef enum mc_error_code {
127         MC_SUCCESS      = 0,
128         MC_IGNORED      = 1,
129         MC_NOTFOUND     = 2,
130         MC_MARKED       = 3,
131         MC_ALLOCATED    = 4,
132 } mc_error_code_t;
133
134 static struct ucode_cpu_info {
135         unsigned int sig;
136         unsigned int pf, orig_pf;
137         unsigned int rev;
138         unsigned int cksum;
139         mc_error_code_t err;
140         microcode_t *mc;
141 } ucode_cpu_info[NR_CPUS];
142                                 
143 static int microcode_open (struct inode *unused1, struct file *unused2)
144 {
145         return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
146 }
147
148 static void collect_cpu_info (void *unused)
149 {
150         int cpu_num = smp_processor_id();
151         struct cpuinfo_x86 *c = cpu_data + cpu_num;
152         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
153         unsigned int val[2];
154
155         uci->sig = uci->pf = uci->rev = uci->cksum = 0;
156         uci->err = MC_NOTFOUND; 
157         uci->mc = NULL;
158
159         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
160                 cpu_has(c, X86_FEATURE_IA64)) {
161                 printk(KERN_ERR "microcode: CPU%d not a capable Intel processor\n", cpu_num);
162                 return;
163         } else {
164                 uci->sig = cpuid_eax(0x00000001);
165
166                 if ((c->x86_model >= 5) || (c->x86 > 6)) {
167                         /* get processor flags from MSR 0x17 */
168                         rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
169                         uci->pf = 1 << ((val[1] >> 18) & 7);
170                 }
171                 uci->orig_pf = uci->pf;
172         }
173
174         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
175         /* see notes above for revision 1.07.  Apparent chip bug */
176         sync_core();
177         /* get the current revision from MSR 0x8B */
178         rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
179         pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
180                         uci->sig, uci->pf, uci->rev);
181 }
182
183 static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
184 {
185         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
186
187         pr_debug("Microcode Found.\n");
188         pr_debug("   Header Revision 0x%x\n", mc_header->hdrver);
189         pr_debug("   Loader Revision 0x%x\n", mc_header->ldrver);
190         pr_debug("   Revision 0x%x \n", mc_header->rev);
191         pr_debug("   Date %x/%x/%x\n",
192                 ((mc_header->date >> 24 ) & 0xff),
193                 ((mc_header->date >> 16 ) & 0xff),
194                 (mc_header->date & 0xFFFF));
195         pr_debug("   Signature 0x%x\n", sig);
196         pr_debug("   Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
197                 ((sig >> 12) & 0x3),
198                 ((sig >> 8) & 0xf),
199                 ((sig >> 4) & 0xf),
200                 ((sig & 0xf)));
201         pr_debug("   Processor Flags 0x%x\n", pf);
202         pr_debug("   Checksum 0x%x\n", cksum);
203
204         if (mc_header->rev < uci->rev) {
205                 if (uci->err == MC_NOTFOUND) {
206                         uci->err = MC_IGNORED;
207                         uci->cksum = mc_header->rev;
208                 } else if (uci->err == MC_IGNORED && uci->cksum < mc_header->rev)
209                         uci->cksum = mc_header->rev;
210         } else if (mc_header->rev == uci->rev) {
211                 if (uci->err < MC_MARKED) {
212                         /* notify the caller of success on this cpu */
213                         uci->err = MC_SUCCESS;
214                 }
215         } else if (uci->err != MC_ALLOCATED || mc_header->rev > uci->mc->hdr.rev) {
216                 pr_debug("microcode: CPU%d found a matching microcode update with "
217                         " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
218                 uci->cksum = cksum;
219                 uci->pf = pf; /* keep the original mc pf for cksum calculation */
220                 uci->err = MC_MARKED; /* found the match */
221                 for_each_online_cpu(cpu_num) {
222                         if (ucode_cpu_info + cpu_num != uci
223                             && ucode_cpu_info[cpu_num].mc == uci->mc) {
224                                 uci->mc = NULL;
225                                 break;
226                         }
227                 }
228                 if (uci->mc != NULL) {
229                         vfree(uci->mc);
230                         uci->mc = NULL;
231                 }
232         }
233         return;
234 }
235
236 static int find_matching_ucodes (void) 
237 {
238         int cursor = 0;
239         int error = 0;
240
241         while (cursor + MC_HEADER_SIZE < user_buffer_size) {
242                 microcode_header_t mc_header;
243                 void *newmc = NULL;
244                 int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
245
246                 if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
247                         printk(KERN_ERR "microcode: error! Can not read user data\n");
248                         error = -EFAULT;
249                         goto out;
250                 }
251
252                 total_size = get_totalsize(&mc_header);
253                 if ((cursor + total_size > user_buffer_size) || (total_size < DEFAULT_UCODE_TOTALSIZE)) {
254                         printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
255                         error = -EINVAL;
256                         goto out;
257                 }
258
259                 data_size = get_datasize(&mc_header);
260                 if ((data_size + MC_HEADER_SIZE > total_size) || (data_size < DEFAULT_UCODE_DATASIZE)) {
261                         printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
262                         error = -EINVAL;
263                         goto out;
264                 }
265
266                 if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
267                         printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
268                         error = -EINVAL;
269                         goto out;
270                 }
271
272                 for_each_online_cpu(cpu_num) {
273                         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
274
275                         if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->orig_pf))
276                                 mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
277                 }
278
279                 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
280                 if (ext_table_size) {
281                         struct extended_sigtable ext_header;
282                         struct extended_signature ext_sig;
283                         int ext_sigcount;
284
285                         if ((ext_table_size < EXT_HEADER_SIZE) 
286                                         || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
287                                 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
288                                 error = -EINVAL;
289                                 goto out;
290                         }
291                         if (copy_from_user(&ext_header, user_buffer + cursor 
292                                         + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
293                                 printk(KERN_ERR "microcode: error! Can not read user data\n");
294                                 error = -EFAULT;
295                                 goto out;
296                         }
297                         if (ext_table_size != exttable_size(&ext_header)) {
298                                 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
299                                 error = -EFAULT;
300                                 goto out;
301                         }
302
303                         ext_sigcount = ext_header.count;
304                         
305                         for (i = 0; i < ext_sigcount; i++) {
306                                 if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE 
307                                                 + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
308                                         printk(KERN_ERR "microcode: error! Can not read user data\n");
309                                         error = -EFAULT;
310                                         goto out;
311                                 }
312                                 for_each_online_cpu(cpu_num) {
313                                         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
314
315                                         if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->orig_pf)) {
316                                                 mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
317                                         }
318                                 }
319                         }
320                 }
321                 /* now check if any cpu has matched */
322                 allocated_flag = 0;
323                 sum = 0;
324                 for_each_online_cpu(cpu_num) {
325                         if (ucode_cpu_info[cpu_num].err == MC_MARKED) { 
326                                 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
327                                 if (!allocated_flag) {
328                                         allocated_flag = 1;
329                                         newmc = vmalloc(total_size);
330                                         if (!newmc) {
331                                                 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
332                                                 error = -ENOMEM;
333                                                 goto out;
334                                         }
335                                         if (copy_from_user(newmc + MC_HEADER_SIZE, 
336                                                                 user_buffer + cursor + MC_HEADER_SIZE, 
337                                                                 total_size - MC_HEADER_SIZE)) {
338                                                 printk(KERN_ERR "microcode: error! Can not read user data\n");
339                                                 vfree(newmc);
340                                                 error = -EFAULT;
341                                                 goto out;
342                                         }
343                                         memcpy(newmc, &mc_header, MC_HEADER_SIZE);
344                                         /* check extended table checksum */
345                                         if (ext_table_size) {
346                                                 int ext_table_sum = 0;
347                                                 int * ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
348                                                 i = ext_table_size / DWSIZE;
349                                                 while (i--) ext_table_sum += ext_tablep[i];
350                                                 if (ext_table_sum) {
351                                                         printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
352                                                         vfree(newmc);
353                                                         error = -EINVAL;
354                                                         goto out;
355                                                 }
356                                         }
357
358                                         /* calculate the checksum */
359                                         i = (MC_HEADER_SIZE + data_size) / DWSIZE;
360                                         while (i--) sum += ((int *)newmc)[i];
361                                         sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
362                                 }
363                                 ucode_cpu_info[cpu_num].mc = newmc;
364                                 ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
365                                 if (sum + uci->sig + uci->pf + uci->cksum != 0) {
366                                         printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
367                                         error = -EINVAL;
368                                         goto out;
369                                 }
370                         }
371                 }
372                 cursor += total_size; /* goto the next update patch */
373         } /* end of while */
374 out:
375         return error;
376 }
377
378 static void do_update_one (void * unused)
379 {
380         unsigned long flags;
381         unsigned int val[2];
382         int cpu_num = smp_processor_id();
383         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
384
385         if (uci->mc == NULL) {
386                 if (verbose) {
387                         if (uci->err == MC_SUCCESS)
388                                 printk(KERN_INFO "microcode: CPU%d already at revision 0x%x\n",
389                                         cpu_num, uci->rev);
390                         else
391                                 printk(KERN_INFO "microcode: No new microcode data for CPU%d\n", cpu_num);
392                 }
393                 return;
394         }
395
396         /* serialize access to the physical write to MSR 0x79 */
397         spin_lock_irqsave(&microcode_update_lock, flags);          
398
399         /* write microcode via MSR 0x79 */
400         wrmsr(MSR_IA32_UCODE_WRITE,
401                 (unsigned long) uci->mc->bits, 
402                 (unsigned long) uci->mc->bits >> 16 >> 16);
403         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
404
405         /* see notes above for revision 1.07.  Apparent chip bug */
406         sync_core();
407
408         /* get the current revision from MSR 0x8B */
409         rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
410
411         /* notify the caller of success on this cpu */
412         uci->err = MC_SUCCESS;
413         spin_unlock_irqrestore(&microcode_update_lock, flags);
414         printk(KERN_INFO "microcode: CPU%d updated from revision "
415                "0x%x to 0x%x, date = %08x \n", 
416                cpu_num, uci->rev, val[1], uci->mc->hdr.date);
417         return;
418 }
419
420 static int do_microcode_update (void)
421 {
422         int i, error;
423
424         if (on_each_cpu(collect_cpu_info, NULL, 1, 1) != 0) {
425                 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
426                 error = -EIO;
427                 goto out;
428         }
429
430         if ((error = find_matching_ucodes())) {
431                 printk(KERN_ERR "microcode: Error in the microcode data\n");
432                 goto out_free;
433         }
434
435         if (on_each_cpu(do_update_one, NULL, 1, 1) != 0) {
436                 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
437                 error = -EIO;
438         }
439
440 out_free:
441         for_each_online_cpu(i) {
442                 if (ucode_cpu_info[i].mc) {
443                         int j;
444                         void *tmp = ucode_cpu_info[i].mc;
445                         vfree(tmp);
446                         for_each_online_cpu(j) {
447                                 if (ucode_cpu_info[j].mc == tmp)
448                                         ucode_cpu_info[j].mc = NULL;
449                         }
450                 }
451                 if (ucode_cpu_info[i].err == MC_IGNORED && verbose)
452                         printk(KERN_WARNING "microcode: CPU%d not 'upgrading' to earlier revision"
453                                " 0x%x (current=0x%x)\n", i, ucode_cpu_info[i].cksum, ucode_cpu_info[i].rev);
454         }
455 out:
456         return error;
457 }
458
459 static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
460 {
461         ssize_t ret;
462
463         if (len < DEFAULT_UCODE_TOTALSIZE) {
464                 printk(KERN_ERR "microcode: not enough data\n"); 
465                 return -EINVAL;
466         }
467
468         if ((len >> PAGE_SHIFT) > num_physpages) {
469                 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
470                 return -EINVAL;
471         }
472
473         mutex_lock(&microcode_mutex);
474
475         user_buffer = (void __user *) buf;
476         user_buffer_size = (int) len;
477
478         ret = do_microcode_update();
479         if (!ret)
480                 ret = (ssize_t)len;
481
482         mutex_unlock(&microcode_mutex);
483
484         return ret;
485 }
486
487 static struct file_operations microcode_fops = {
488         .owner          = THIS_MODULE,
489         .write          = microcode_write,
490         .open           = microcode_open,
491 };
492
493 static struct miscdevice microcode_dev = {
494         .minor          = MICROCODE_MINOR,
495         .name           = "microcode",
496         .fops           = &microcode_fops,
497 };
498
499 static int __init microcode_init (void)
500 {
501         int error;
502
503         error = misc_register(&microcode_dev);
504         if (error) {
505                 printk(KERN_ERR
506                         "microcode: can't misc_register on minor=%d\n",
507                         MICROCODE_MINOR);
508                 return error;
509         }
510
511         printk(KERN_INFO 
512                 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
513         return 0;
514 }
515
516 static void __exit microcode_exit (void)
517 {
518         misc_deregister(&microcode_dev);
519 }
520
521 module_init(microcode_init)
522 module_exit(microcode_exit)
523 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);