2 * Intel CPU Microcode Update Driver for Linux
4 * Copyright (C) 2000-2004 Tigran Aivazian
5 * 2006 Shaohua Li <shaohua.li@intel.com>
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.
11 * Reference: Section 8.10 of Volume III, Intel Pentium 4 Manual,
12 * Order Number 245472 or free download from:
14 * http://developer.intel.com/design/pentium4/manuals/245472.htm
16 * For more information, go to http://www.urbanmyth.org/microcode
18 * This program is free software; you can redistribute it and/or
19 * modify it under the terms of the GNU General Public License
20 * as published by the Free Software Foundation; either version
21 * 2 of the License, or (at your option) any later version.
23 * 1.0 16 Feb 2000, Tigran Aivazian <tigran@sco.com>
25 * 1.01 18 Feb 2000, Tigran Aivazian <tigran@sco.com>
26 * Added read() support + cleanups.
27 * 1.02 21 Feb 2000, Tigran Aivazian <tigran@sco.com>
28 * Added 'device trimming' support. open(O_WRONLY) zeroes
29 * and frees the saved copy of applied microcode.
30 * 1.03 29 Feb 2000, Tigran Aivazian <tigran@sco.com>
31 * Made to use devfs (/dev/cpu/microcode) + cleanups.
32 * 1.04 06 Jun 2000, Simon Trimmer <simon@veritas.com>
33 * Added misc device support (now uses both devfs and misc).
34 * Added MICROCODE_IOCFREE ioctl to clear memory.
35 * 1.05 09 Jun 2000, Simon Trimmer <simon@veritas.com>
36 * Messages for error cases (non Intel & no suitable microcode).
37 * 1.06 03 Aug 2000, Tigran Aivazian <tigran@veritas.com>
38 * Removed ->release(). Removed exclusive open and status bitmap.
39 * Added microcode_rwsem to serialize read()/write()/ioctl().
40 * Removed global kernel lock usage.
41 * 1.07 07 Sep 2000, Tigran Aivazian <tigran@veritas.com>
42 * Write 0 to 0x8B msr and then cpuid before reading revision,
43 * so that it works even if there were no update done by the
44 * BIOS. Otherwise, reading from 0x8B gives junk (which happened
45 * to be 0 on my machine which is why it worked even when I
46 * disabled update by the BIOS)
47 * Thanks to Eric W. Biederman <ebiederman@lnxi.com> for the fix.
48 * 1.08 11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and
49 * Tigran Aivazian <tigran@veritas.com>
50 * Intel Pentium 4 processor support and bugfixes.
51 * 1.09 30 Oct 2001, Tigran Aivazian <tigran@veritas.com>
52 * Bugfix for HT (Hyper-Threading) enabled processors
53 * whereby processor resources are shared by all logical processors
54 * in a single CPU package.
55 * 1.10 28 Feb 2002 Asit K Mallick <asit.k.mallick@intel.com> and
56 * Tigran Aivazian <tigran@veritas.com>,
57 * Serialize updates as required on HT processors due to speculative
58 * nature of implementation.
59 * 1.11 22 Mar 2002 Tigran Aivazian <tigran@veritas.com>
60 * Fix the panic when writing zero-length microcode chunk.
61 * 1.12 29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>,
62 * Jun Nakajima <jun.nakajima@intel.com>
63 * Support for the microcode updates in the new format.
64 * 1.13 10 Oct 2003 Tigran Aivazian <tigran@veritas.com>
65 * Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl
66 * because we no longer hold a copy of applied microcode
68 * 1.14 25 Jun 2004 Tigran Aivazian <tigran@veritas.com>
69 * Fix sigmatch() macro to handle old CPUs with pf == 0.
70 * Thanks to Stuart Swales for pointing out this bug.
73 //#define DEBUG /* pr_debug */
74 #include <linux/capability.h>
75 #include <linux/kernel.h>
76 #include <linux/init.h>
77 #include <linux/sched.h>
78 #include <linux/cpumask.h>
79 #include <linux/module.h>
80 #include <linux/slab.h>
81 #include <linux/vmalloc.h>
82 #include <linux/miscdevice.h>
83 #include <linux/spinlock.h>
85 #include <linux/mutex.h>
86 #include <linux/cpu.h>
87 #include <linux/firmware.h>
88 #include <linux/platform_device.h>
91 #include <asm/uaccess.h>
92 #include <asm/processor.h>
94 MODULE_DESCRIPTION("Intel CPU (IA-32) Microcode Update Driver");
95 MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
96 MODULE_LICENSE("GPL");
98 #define MICROCODE_VERSION "1.14a"
100 #define DEFAULT_UCODE_DATASIZE (2000) /* 2000 bytes */
101 #define MC_HEADER_SIZE (sizeof (microcode_header_t)) /* 48 bytes */
102 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
103 #define EXT_HEADER_SIZE (sizeof (struct extended_sigtable)) /* 20 bytes */
104 #define EXT_SIGNATURE_SIZE (sizeof (struct extended_signature)) /* 12 bytes */
105 #define DWSIZE (sizeof (u32))
106 #define get_totalsize(mc) \
107 (((microcode_t *)mc)->hdr.totalsize ? \
108 ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
109 #define get_datasize(mc) \
110 (((microcode_t *)mc)->hdr.datasize ? \
111 ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
113 #define sigmatch(s1, s2, p1, p2) \
114 (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
116 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
118 /* serialize access to the physical write to MSR 0x79 */
119 static DEFINE_SPINLOCK(microcode_update_lock
);
121 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
122 static DEFINE_MUTEX(microcode_mutex
);
124 static struct ucode_cpu_info
{
130 } ucode_cpu_info
[NR_CPUS
];
132 static void collect_cpu_info(int cpu_num
)
134 struct cpuinfo_x86
*c
= cpu_data
+ cpu_num
;
135 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu_num
;
138 /* We should bind the task to the CPU */
139 BUG_ON(raw_smp_processor_id() != cpu_num
);
140 uci
->pf
= uci
->rev
= 0;
144 if (c
->x86_vendor
!= X86_VENDOR_INTEL
|| c
->x86
< 6 ||
145 cpu_has(c
, X86_FEATURE_IA64
)) {
146 printk(KERN_ERR
"microcode: CPU%d not a capable Intel "
147 "processor\n", cpu_num
);
152 uci
->sig
= cpuid_eax(0x00000001);
154 if ((c
->x86_model
>= 5) || (c
->x86
> 6)) {
155 /* get processor flags from MSR 0x17 */
156 rdmsr(MSR_IA32_PLATFORM_ID
, val
[0], val
[1]);
157 uci
->pf
= 1 << ((val
[1] >> 18) & 7);
160 wrmsr(MSR_IA32_UCODE_REV
, 0, 0);
161 /* see notes above for revision 1.07. Apparent chip bug */
163 /* get the current revision from MSR 0x8B */
164 rdmsr(MSR_IA32_UCODE_REV
, val
[0], uci
->rev
);
165 pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
166 uci
->sig
, uci
->pf
, uci
->rev
);
169 static inline int microcode_update_match(int cpu_num
,
170 microcode_header_t
*mc_header
, int sig
, int pf
)
172 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu_num
;
174 if (!sigmatch(sig
, uci
->sig
, pf
, uci
->pf
)
175 || mc_header
->rev
<= uci
->rev
)
180 static int microcode_sanity_check(void *mc
)
182 microcode_header_t
*mc_header
= mc
;
183 struct extended_sigtable
*ext_header
= NULL
;
184 struct extended_signature
*ext_sig
;
185 unsigned long total_size
, data_size
, ext_table_size
;
186 int sum
, orig_sum
, ext_sigcount
= 0, i
;
188 total_size
= get_totalsize(mc_header
);
189 data_size
= get_datasize(mc_header
);
190 if ((data_size
+ MC_HEADER_SIZE
> total_size
)
191 || (data_size
< DEFAULT_UCODE_DATASIZE
)) {
192 printk(KERN_ERR
"microcode: error! "
193 "Bad data size in microcode data file\n");
197 if (mc_header
->ldrver
!= 1 || mc_header
->hdrver
!= 1) {
198 printk(KERN_ERR
"microcode: error! "
199 "Unknown microcode update format\n");
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 printk(KERN_ERR
"microcode: error! "
207 "Small exttable size in microcode data file\n");
210 ext_header
= mc
+ MC_HEADER_SIZE
+ data_size
;
211 if (ext_table_size
!= exttable_size(ext_header
)) {
212 printk(KERN_ERR
"microcode: error! "
213 "Bad exttable size in microcode data file\n");
216 ext_sigcount
= ext_header
->count
;
219 /* check extended table checksum */
220 if (ext_table_size
) {
221 int ext_table_sum
= 0;
222 int * ext_tablep
= (int *)ext_header
;
224 i
= ext_table_size
/ DWSIZE
;
226 ext_table_sum
+= ext_tablep
[i
];
228 printk(KERN_WARNING
"microcode: aborting, "
229 "bad extended signature table checksum\n");
234 /* calculate the checksum */
236 i
= (MC_HEADER_SIZE
+ data_size
) / DWSIZE
;
238 orig_sum
+= ((int *)mc
)[i
];
240 printk(KERN_ERR
"microcode: aborting, bad checksum\n");
245 /* check extended signature checksum */
246 for (i
= 0; i
< ext_sigcount
; i
++) {
247 ext_sig
= (struct extended_signature
*)((void *)ext_header
248 + EXT_HEADER_SIZE
+ EXT_SIGNATURE_SIZE
* i
);
250 - (mc_header
->sig
+ mc_header
->pf
+ mc_header
->cksum
)
251 + (ext_sig
->sig
+ ext_sig
->pf
+ ext_sig
->cksum
);
253 printk(KERN_ERR
"microcode: aborting, bad checksum\n");
261 * return 0 - no update found
262 * return 1 - found update
265 static int get_maching_microcode(void *mc
, int cpu
)
267 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu
;
268 microcode_header_t
*mc_header
= mc
;
269 struct extended_sigtable
*ext_header
;
270 unsigned long total_size
= get_totalsize(mc_header
);
272 struct extended_signature
*ext_sig
;
275 if (microcode_update_match(cpu
, mc_header
,
276 mc_header
->sig
, mc_header
->pf
))
279 if (total_size
<= get_datasize(mc_header
) + MC_HEADER_SIZE
)
282 ext_header
= (struct extended_sigtable
*)(mc
+
283 get_datasize(mc_header
) + MC_HEADER_SIZE
);
284 ext_sigcount
= ext_header
->count
;
285 ext_sig
= (struct extended_signature
*)((void *)ext_header
287 for (i
= 0; i
< ext_sigcount
; i
++) {
288 if (microcode_update_match(cpu
, mc_header
,
289 ext_sig
->sig
, ext_sig
->pf
))
295 pr_debug("microcode: CPU %d found a matching microcode update with"
296 " version 0x%x (current=0x%x)\n", cpu
, mc_header
->rev
,uci
->rev
);
297 new_mc
= vmalloc(total_size
);
299 printk(KERN_ERR
"microcode: error! Can not allocate memory\n");
303 /* free previous update file */
306 memcpy(new_mc
, mc
, total_size
);
311 static void apply_microcode(int cpu
)
315 int cpu_num
= raw_smp_processor_id();
316 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu_num
;
318 /* We should bind the task to the CPU */
319 BUG_ON(cpu_num
!= cpu
);
324 /* serialize access to the physical write to MSR 0x79 */
325 spin_lock_irqsave(µcode_update_lock
, flags
);
327 /* write microcode via MSR 0x79 */
328 wrmsr(MSR_IA32_UCODE_WRITE
,
329 (unsigned long) uci
->mc
->bits
,
330 (unsigned long) uci
->mc
->bits
>> 16 >> 16);
331 wrmsr(MSR_IA32_UCODE_REV
, 0, 0);
333 /* see notes above for revision 1.07. Apparent chip bug */
336 /* get the current revision from MSR 0x8B */
337 rdmsr(MSR_IA32_UCODE_REV
, val
[0], val
[1]);
339 spin_unlock_irqrestore(µcode_update_lock
, flags
);
340 if (val
[1] != uci
->mc
->hdr
.rev
) {
341 printk(KERN_ERR
"microcode: CPU%d updated from revision "
342 "0x%x to 0x%x failed\n", cpu_num
, uci
->rev
, val
[1]);
345 pr_debug("microcode: CPU%d updated from revision "
346 "0x%x to 0x%x, date = %08x \n",
347 cpu_num
, uci
->rev
, val
[1], uci
->mc
->hdr
.date
);
351 #ifdef CONFIG_MICROCODE_OLD_INTERFACE
352 static void __user
*user_buffer
; /* user area microcode data buffer */
353 static unsigned int user_buffer_size
; /* it's size */
355 static long get_next_ucode(void **mc
, long offset
)
357 microcode_header_t mc_header
;
358 unsigned long total_size
;
361 if (offset
>= user_buffer_size
)
363 if (copy_from_user(&mc_header
, user_buffer
+ offset
, MC_HEADER_SIZE
)) {
364 printk(KERN_ERR
"microcode: error! Can not read user data\n");
367 total_size
= get_totalsize(&mc_header
);
368 if ((offset
+ total_size
> user_buffer_size
)
369 || (total_size
< DEFAULT_UCODE_TOTALSIZE
)) {
370 printk(KERN_ERR
"microcode: error! Bad total size in microcode "
374 *mc
= vmalloc(total_size
);
377 if (copy_from_user(*mc
, user_buffer
+ offset
, total_size
)) {
378 printk(KERN_ERR
"microcode: error! Can not read user data\n");
382 return offset
+ total_size
;
385 static int do_microcode_update (void)
393 old
= current
->cpus_allowed
;
395 while ((cursor
= get_next_ucode(&new_mc
, cursor
)) > 0) {
396 error
= microcode_sanity_check(new_mc
);
400 * It's possible the data file has multiple matching ucode,
401 * lets keep searching till the latest version
403 for_each_online_cpu(cpu
) {
404 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu
;
408 set_cpus_allowed(current
, cpumask_of_cpu(cpu
));
409 error
= get_maching_microcode(new_mc
, cpu
);
413 apply_microcode(cpu
);
422 set_cpus_allowed(current
, old
);
426 static int microcode_open (struct inode
*unused1
, struct file
*unused2
)
428 return capable(CAP_SYS_RAWIO
) ? 0 : -EPERM
;
431 static ssize_t
microcode_write (struct file
*file
, const char __user
*buf
, size_t len
, loff_t
*ppos
)
435 if (len
< DEFAULT_UCODE_TOTALSIZE
) {
436 printk(KERN_ERR
"microcode: not enough data\n");
440 if ((len
>> PAGE_SHIFT
) > num_physpages
) {
441 printk(KERN_ERR
"microcode: too much data (max %ld pages)\n", num_physpages
);
446 mutex_lock(µcode_mutex
);
448 user_buffer
= (void __user
*) buf
;
449 user_buffer_size
= (int) len
;
451 ret
= do_microcode_update();
455 mutex_unlock(µcode_mutex
);
456 unlock_cpu_hotplug();
461 static struct file_operations microcode_fops
= {
462 .owner
= THIS_MODULE
,
463 .write
= microcode_write
,
464 .open
= microcode_open
,
467 static struct miscdevice microcode_dev
= {
468 .minor
= MICROCODE_MINOR
,
470 .fops
= µcode_fops
,
473 static int __init
microcode_dev_init (void)
477 error
= misc_register(µcode_dev
);
480 "microcode: can't misc_register on minor=%d\n",
488 static void __exit
microcode_dev_exit (void)
490 misc_deregister(µcode_dev
);
493 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR
);
495 #define microcode_dev_init() 0
496 #define microcode_dev_exit() do { } while(0)
499 static long get_next_ucode_from_buffer(void **mc
, void *buf
,
500 unsigned long size
, long offset
)
502 microcode_header_t
*mc_header
;
503 unsigned long total_size
;
508 mc_header
= (microcode_header_t
*)(buf
+ offset
);
509 total_size
= get_totalsize(mc_header
);
511 if ((offset
+ total_size
> size
)
512 || (total_size
< DEFAULT_UCODE_TOTALSIZE
)) {
513 printk(KERN_ERR
"microcode: error! Bad data in microcode data file\n");
517 *mc
= vmalloc(total_size
);
519 printk(KERN_ERR
"microcode: error! Can not allocate memory\n");
522 memcpy(*mc
, buf
+ offset
, total_size
);
523 return offset
+ total_size
;
526 /* fake device for request_firmware */
527 static struct platform_device
*microcode_pdev
;
529 static int cpu_request_microcode(int cpu
)
532 struct cpuinfo_x86
*c
= cpu_data
+ cpu
;
533 const struct firmware
*firmware
;
540 /* We should bind the task to the CPU */
541 BUG_ON(cpu
!= raw_smp_processor_id());
542 sprintf(name
,"intel-ucode/%02x-%02x-%02x",
543 c
->x86
, c
->x86_model
, c
->x86_mask
);
544 error
= request_firmware(&firmware
, name
, µcode_pdev
->dev
);
546 pr_debug("ucode data file %s load failed\n", name
);
549 buf
= (void *)firmware
->data
;
550 size
= firmware
->size
;
551 while ((offset
= get_next_ucode_from_buffer(&mc
, buf
, size
, offset
))
553 error
= microcode_sanity_check(mc
);
556 error
= get_maching_microcode(mc
, cpu
);
560 * It's possible the data file has multiple matching ucode,
561 * lets keep searching till the latest version
564 apply_microcode(cpu
);
573 release_firmware(firmware
);
578 static void microcode_init_cpu(int cpu
)
581 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu
;
583 old
= current
->cpus_allowed
;
585 set_cpus_allowed(current
, cpumask_of_cpu(cpu
));
586 mutex_lock(µcode_mutex
);
587 collect_cpu_info(cpu
);
589 cpu_request_microcode(cpu
);
590 mutex_unlock(µcode_mutex
);
591 set_cpus_allowed(current
, old
);
594 static void microcode_fini_cpu(int cpu
)
596 struct ucode_cpu_info
*uci
= ucode_cpu_info
+ cpu
;
598 mutex_lock(µcode_mutex
);
602 mutex_unlock(µcode_mutex
);
605 static int __init
microcode_init (void)
609 error
= microcode_dev_init();
612 microcode_pdev
= platform_device_register_simple("microcode", -1,
614 if (IS_ERR(microcode_pdev
)) {
615 microcode_dev_exit();
616 return PTR_ERR(microcode_pdev
);
620 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION
" <tigran@veritas.com>\n");
624 static void __exit
microcode_exit (void)
626 microcode_dev_exit();
627 platform_device_unregister(microcode_pdev
);
630 module_init(microcode_init
)
631 module_exit(microcode_exit
)