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 ssize_t reload_store(struct sys_device *dev, const char *buf, size_t sz)
607 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
609 unsigned long val = simple_strtoul(buf, &end, 0);
618 old = current->cpus_allowed;
621 set_cpus_allowed(current, cpumask_of_cpu(cpu));
623 mutex_lock(µcode_mutex);
625 err = cpu_request_microcode(cpu);
626 mutex_unlock(µcode_mutex);
627 unlock_cpu_hotplug();
628 set_cpus_allowed(current, old);
635 static ssize_t version_show(struct sys_device *dev, char *buf)
637 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
639 return sprintf(buf, "0x%x\n", uci->rev);
642 static ssize_t pf_show(struct sys_device *dev, char *buf)
644 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
646 return sprintf(buf, "0x%x\n", uci->pf);
649 static SYSDEV_ATTR(reload, 0200, NULL, reload_store);
650 static SYSDEV_ATTR(version, 0400, version_show, NULL);
651 static SYSDEV_ATTR(processor_flags, 0400, pf_show, NULL);
653 static struct attribute *mc_default_attrs[] = {
656 &attr_processor_flags.attr,
660 static struct attribute_group mc_attr_group = {
661 .attrs = mc_default_attrs,
665 static int mc_sysdev_add(struct sys_device *sys_dev)
667 int cpu = sys_dev->id;
668 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
670 if (!cpu_online(cpu))
672 pr_debug("Microcode:CPU %d added\n", cpu);
673 memset(uci, 0, sizeof(*uci));
674 sysfs_create_group(&sys_dev->kobj, &mc_attr_group);
676 microcode_init_cpu(cpu);
680 static int mc_sysdev_remove(struct sys_device *sys_dev)
682 int cpu = sys_dev->id;
684 if (!cpu_online(cpu))
686 pr_debug("Microcode:CPU %d removed\n", cpu);
687 microcode_fini_cpu(cpu);
688 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
692 static int mc_sysdev_resume(struct sys_device *dev)
696 if (!cpu_online(cpu))
698 pr_debug("Microcode:CPU %d resumed\n", cpu);
699 /* only CPU 0 will apply ucode here */
704 static struct sysdev_driver mc_sysdev_driver = {
705 .add = mc_sysdev_add,
706 .remove = mc_sysdev_remove,
707 .resume = mc_sysdev_resume,
710 #ifdef CONFIG_HOTPLUG_CPU
712 mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
714 unsigned int cpu = (unsigned long)hcpu;
715 struct sys_device *sys_dev;
717 sys_dev = get_cpu_sysdev(cpu);
720 case CPU_DOWN_FAILED:
721 mc_sysdev_add(sys_dev);
723 case CPU_DOWN_PREPARE:
724 mc_sysdev_remove(sys_dev);
730 static struct notifier_block mc_cpu_notifier = {
731 .notifier_call = mc_cpu_callback,
735 static int __init microcode_init (void)
739 error = microcode_dev_init();
742 microcode_pdev = platform_device_register_simple("microcode", -1,
744 if (IS_ERR(microcode_pdev)) {
745 microcode_dev_exit();
746 return PTR_ERR(microcode_pdev);
750 error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver);
751 unlock_cpu_hotplug();
753 microcode_dev_exit();
754 platform_device_unregister(microcode_pdev);
758 register_hotcpu_notifier(&mc_cpu_notifier);
761 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
765 static void __exit microcode_exit (void)
767 microcode_dev_exit();
769 unregister_hotcpu_notifier(&mc_cpu_notifier);
772 sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver);
773 unlock_cpu_hotplug();
775 platform_device_unregister(microcode_pdev);
778 module_init(microcode_init)
779 module_exit(microcode_exit)