dd780a00553f3eeeeb038c25824d8a8346a00114
[linux-2.6.git] / 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 #define MICROCODE_VERSION       "1.14"
95
96 #define DEFAULT_UCODE_DATASIZE  (2000)    /* 2000 bytes */
97 #define MC_HEADER_SIZE          (sizeof (microcode_header_t))     /* 48 bytes */
98 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
99 #define EXT_HEADER_SIZE         (sizeof (struct extended_sigtable)) /* 20 bytes */
100 #define EXT_SIGNATURE_SIZE      (sizeof (struct extended_signature)) /* 12 bytes */
101 #define DWSIZE                  (sizeof (u32))
102 #define get_totalsize(mc) \
103         (((microcode_t *)mc)->hdr.totalsize ? \
104          ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
105 #define get_datasize(mc) \
106         (((microcode_t *)mc)->hdr.datasize ? \
107          ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
108
109 #define sigmatch(s1, s2, p1, p2) \
110         (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
111
112 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
113
114 /* serialize access to the physical write to MSR 0x79 */
115 static DEFINE_SPINLOCK(microcode_update_lock);
116
117 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
118 static DEFINE_MUTEX(microcode_mutex);
119
120 static void __user *user_buffer;        /* user area microcode data buffer */
121 static unsigned int user_buffer_size;   /* it's size */
122
123 typedef enum mc_error_code {
124         MC_SUCCESS      = 0,
125         MC_NOTFOUND     = 1,
126         MC_MARKED       = 2,
127         MC_ALLOCATED    = 3,
128 } mc_error_code_t;
129
130 static struct ucode_cpu_info {
131         unsigned int sig;
132         unsigned int pf;
133         unsigned int rev;
134         unsigned int cksum;
135         mc_error_code_t err;
136         microcode_t *mc;
137 } ucode_cpu_info[NR_CPUS];
138                                 
139 static int microcode_open (struct inode *unused1, struct file *unused2)
140 {
141         return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
142 }
143
144 static void collect_cpu_info (void *unused)
145 {
146         int cpu_num = smp_processor_id();
147         struct cpuinfo_x86 *c = cpu_data + cpu_num;
148         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
149         unsigned int val[2];
150
151         uci->sig = uci->pf = uci->rev = uci->cksum = 0;
152         uci->err = MC_NOTFOUND; 
153         uci->mc = NULL;
154
155         if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
156                 cpu_has(c, X86_FEATURE_IA64)) {
157                 printk(KERN_ERR "microcode: CPU%d not a capable Intel processor\n", cpu_num);
158                 return;
159         } else {
160                 uci->sig = cpuid_eax(0x00000001);
161
162                 if ((c->x86_model >= 5) || (c->x86 > 6)) {
163                         /* get processor flags from MSR 0x17 */
164                         rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
165                         uci->pf = 1 << ((val[1] >> 18) & 7);
166                 }
167         }
168
169         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
170         /* see notes above for revision 1.07.  Apparent chip bug */
171         sync_core();
172         /* get the current revision from MSR 0x8B */
173         rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
174         pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
175                         uci->sig, uci->pf, uci->rev);
176 }
177
178 static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
179 {
180         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
181
182         pr_debug("Microcode Found.\n");
183         pr_debug("   Header Revision 0x%x\n", mc_header->hdrver);
184         pr_debug("   Loader Revision 0x%x\n", mc_header->ldrver);
185         pr_debug("   Revision 0x%x \n", mc_header->rev);
186         pr_debug("   Date %x/%x/%x\n",
187                 ((mc_header->date >> 24 ) & 0xff),
188                 ((mc_header->date >> 16 ) & 0xff),
189                 (mc_header->date & 0xFFFF));
190         pr_debug("   Signature 0x%x\n", sig);
191         pr_debug("   Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
192                 ((sig >> 12) & 0x3),
193                 ((sig >> 8) & 0xf),
194                 ((sig >> 4) & 0xf),
195                 ((sig & 0xf)));
196         pr_debug("   Processor Flags 0x%x\n", pf);
197         pr_debug("   Checksum 0x%x\n", cksum);
198
199         if (mc_header->rev < uci->rev) {
200                 printk(KERN_ERR "microcode: CPU%d not 'upgrading' to earlier revision"
201                        " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
202                 goto out;
203         } else if (mc_header->rev == uci->rev) {
204                 /* notify the caller of success on this cpu */
205                 uci->err = MC_SUCCESS;
206                 goto out;
207         }
208
209         pr_debug("microcode: CPU%d found a matching microcode update with "
210                 " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
211         uci->cksum = cksum;
212         uci->pf = pf; /* keep the original mc pf for cksum calculation */
213         uci->err = MC_MARKED; /* found the match */
214 out:
215         return;
216 }
217
218 static int find_matching_ucodes (void) 
219 {
220         int cursor = 0;
221         int error = 0;
222
223         while (cursor + MC_HEADER_SIZE < user_buffer_size) {
224                 microcode_header_t mc_header;
225                 void *newmc = NULL;
226                 int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
227
228                 if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
229                         printk(KERN_ERR "microcode: error! Can not read user data\n");
230                         error = -EFAULT;
231                         goto out;
232                 }
233
234                 total_size = get_totalsize(&mc_header);
235                 if ((cursor + total_size > user_buffer_size) || (total_size < DEFAULT_UCODE_TOTALSIZE)) {
236                         printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
237                         error = -EINVAL;
238                         goto out;
239                 }
240
241                 data_size = get_datasize(&mc_header);
242                 if ((data_size + MC_HEADER_SIZE > total_size) || (data_size < DEFAULT_UCODE_DATASIZE)) {
243                         printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
244                         error = -EINVAL;
245                         goto out;
246                 }
247
248                 if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
249                         printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
250                         error = -EINVAL;
251                         goto out;
252                 }
253
254                 for_each_online_cpu(cpu_num) {
255                         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
256                         if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
257                                 continue;
258
259                         if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->pf))
260                                 mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
261                 }
262
263                 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
264                 if (ext_table_size) {
265                         struct extended_sigtable ext_header;
266                         struct extended_signature ext_sig;
267                         int ext_sigcount;
268
269                         if ((ext_table_size < EXT_HEADER_SIZE) 
270                                         || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
271                                 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
272                                 error = -EINVAL;
273                                 goto out;
274                         }
275                         if (copy_from_user(&ext_header, user_buffer + cursor 
276                                         + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
277                                 printk(KERN_ERR "microcode: error! Can not read user data\n");
278                                 error = -EFAULT;
279                                 goto out;
280                         }
281                         if (ext_table_size != exttable_size(&ext_header)) {
282                                 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
283                                 error = -EFAULT;
284                                 goto out;
285                         }
286
287                         ext_sigcount = ext_header.count;
288                         
289                         for (i = 0; i < ext_sigcount; i++) {
290                                 if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE 
291                                                 + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
292                                         printk(KERN_ERR "microcode: error! Can not read user data\n");
293                                         error = -EFAULT;
294                                         goto out;
295                                 }
296                                 for_each_online_cpu(cpu_num) {
297                                         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
298                                         if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
299                                                 continue;
300                                         if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->pf)) {
301                                                 mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
302                                         }
303                                 }
304                         }
305                 }
306                 /* now check if any cpu has matched */
307                 allocated_flag = 0;
308                 sum = 0;
309                 for_each_online_cpu(cpu_num) {
310                         if (ucode_cpu_info[cpu_num].err == MC_MARKED) { 
311                                 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
312                                 if (!allocated_flag) {
313                                         allocated_flag = 1;
314                                         newmc = vmalloc(total_size);
315                                         if (!newmc) {
316                                                 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
317                                                 error = -ENOMEM;
318                                                 goto out;
319                                         }
320                                         if (copy_from_user(newmc + MC_HEADER_SIZE, 
321                                                                 user_buffer + cursor + MC_HEADER_SIZE, 
322                                                                 total_size - MC_HEADER_SIZE)) {
323                                                 printk(KERN_ERR "microcode: error! Can not read user data\n");
324                                                 vfree(newmc);
325                                                 error = -EFAULT;
326                                                 goto out;
327                                         }
328                                         memcpy(newmc, &mc_header, MC_HEADER_SIZE);
329                                         /* check extended table checksum */
330                                         if (ext_table_size) {
331                                                 int ext_table_sum = 0;
332                                                 int * ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
333                                                 i = ext_table_size / DWSIZE;
334                                                 while (i--) ext_table_sum += ext_tablep[i];
335                                                 if (ext_table_sum) {
336                                                         printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
337                                                         vfree(newmc);
338                                                         error = -EINVAL;
339                                                         goto out;
340                                                 }
341                                         }
342
343                                         /* calculate the checksum */
344                                         i = (MC_HEADER_SIZE + data_size) / DWSIZE;
345                                         while (i--) sum += ((int *)newmc)[i];
346                                         sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
347                                 }
348                                 ucode_cpu_info[cpu_num].mc = newmc;
349                                 ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
350                                 if (sum + uci->sig + uci->pf + uci->cksum != 0) {
351                                         printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
352                                         error = -EINVAL;
353                                         goto out;
354                                 }
355                         }
356                 }
357                 cursor += total_size; /* goto the next update patch */
358         } /* end of while */
359 out:
360         return error;
361 }
362
363 static void do_update_one (void * unused)
364 {
365         unsigned long flags;
366         unsigned int val[2];
367         int cpu_num = smp_processor_id();
368         struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
369
370         if (uci->mc == NULL) {
371                 return;
372         }
373
374         /* serialize access to the physical write to MSR 0x79 */
375         spin_lock_irqsave(&microcode_update_lock, flags);          
376
377         /* write microcode via MSR 0x79 */
378         wrmsr(MSR_IA32_UCODE_WRITE,
379                 (unsigned long) uci->mc->bits, 
380                 (unsigned long) uci->mc->bits >> 16 >> 16);
381         wrmsr(MSR_IA32_UCODE_REV, 0, 0);
382
383         /* see notes above for revision 1.07.  Apparent chip bug */
384         sync_core();
385
386         /* get the current revision from MSR 0x8B */
387         rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
388
389         /* notify the caller of success on this cpu */
390         uci->err = MC_SUCCESS;
391         spin_unlock_irqrestore(&microcode_update_lock, flags);
392         printk(KERN_INFO "microcode: CPU%d updated from revision "
393                "0x%x to 0x%x, date = %08x \n", 
394                cpu_num, uci->rev, val[1], uci->mc->hdr.date);
395         return;
396 }
397
398 static int do_microcode_update (void)
399 {
400         int i, error;
401
402         if (on_each_cpu(collect_cpu_info, NULL, 1, 1) != 0) {
403                 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
404                 error = -EIO;
405                 goto out;
406         }
407
408         if ((error = find_matching_ucodes())) {
409                 printk(KERN_ERR "microcode: Error in the microcode data\n");
410                 goto out_free;
411         }
412
413         if (on_each_cpu(do_update_one, NULL, 1, 1) != 0) {
414                 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
415                 error = -EIO;
416         }
417
418 out_free:
419         for_each_online_cpu(i) {
420                 if (ucode_cpu_info[i].mc) {
421                         int j;
422                         void *tmp = ucode_cpu_info[i].mc;
423                         vfree(tmp);
424                         for_each_online_cpu(j) {
425                                 if (ucode_cpu_info[j].mc == tmp)
426                                         ucode_cpu_info[j].mc = NULL;
427                         }
428                 }
429         }
430 out:
431         return error;
432 }
433
434 static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
435 {
436         ssize_t ret;
437
438         if (len < DEFAULT_UCODE_TOTALSIZE) {
439                 printk(KERN_ERR "microcode: not enough data\n"); 
440                 return -EINVAL;
441         }
442
443         if ((len >> PAGE_SHIFT) > num_physpages) {
444                 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
445                 return -EINVAL;
446         }
447
448         mutex_lock(&microcode_mutex);
449
450         user_buffer = (void __user *) buf;
451         user_buffer_size = (int) len;
452
453         ret = do_microcode_update();
454         if (!ret)
455                 ret = (ssize_t)len;
456
457         mutex_unlock(&microcode_mutex);
458
459         return ret;
460 }
461
462 static int microcode_ioctl (struct inode *inode, struct file *file, 
463                 unsigned int cmd, unsigned long arg)
464 {
465         switch (cmd) {
466                 /* 
467                  *  XXX: will be removed after microcode_ctl 
468                  *  is updated to ignore failure of this ioctl()
469                  */
470                 case MICROCODE_IOCFREE:
471                         return 0;
472                 default:
473                         return -EINVAL;
474         }
475         return -EINVAL;
476 }
477
478 static struct file_operations microcode_fops = {
479         .owner          = THIS_MODULE,
480         .write          = microcode_write,
481         .ioctl          = microcode_ioctl,
482         .open           = microcode_open,
483 };
484
485 static struct miscdevice microcode_dev = {
486         .minor          = MICROCODE_MINOR,
487         .name           = "microcode",
488         .devfs_name     = "cpu/microcode",
489         .fops           = &microcode_fops,
490 };
491
492 static int __init microcode_init (void)
493 {
494         int error;
495
496         error = misc_register(&microcode_dev);
497         if (error) {
498                 printk(KERN_ERR
499                         "microcode: can't misc_register on minor=%d\n",
500                         MICROCODE_MINOR);
501                 return error;
502         }
503
504         printk(KERN_INFO 
505                 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
506         return 0;
507 }
508
509 static void __exit microcode_exit (void)
510 {
511         misc_deregister(&microcode_dev);
512 }
513
514 module_init(microcode_init)
515 module_exit(microcode_exit)
516 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);