2 * Intel CPU Microcode Update Driver for Linux
4 * Copyright (C) 2000-2004 Tigran Aivazian
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.
10 * Reference: Section 8.10 of Volume III, Intel Pentium 4 Manual,
11 * Order Number 245472 or free download from:
13 * http://developer.intel.com/design/pentium4/manuals/245472.htm
15 * For more information, go to http://www.urbanmyth.org/microcode
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.
22 * 1.0 16 Feb 2000, Tigran Aivazian <tigran@sco.com>
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
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.
73 #include <linux/init.h>
74 #include <linux/sched.h>
75 #include <linux/module.h>
76 #include <linux/slab.h>
77 #include <linux/vmalloc.h>
78 #include <linux/miscdevice.h>
79 #include <linux/spinlock.h>
83 #include <asm/uaccess.h>
84 #include <asm/processor.h>
86 MODULE_DESCRIPTION("Intel CPU (IA-32) Microcode Update Driver");
87 MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
88 MODULE_LICENSE("GPL");
90 #define MICROCODE_VERSION "1.14"
93 #define dprintk(x...) printk(KERN_INFO x)
98 #define DEFAULT_UCODE_DATASIZE (2000) /* 2000 bytes */
99 #define MC_HEADER_SIZE (sizeof (microcode_header_t)) /* 48 bytes */
100 #define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
101 #define EXT_HEADER_SIZE (sizeof (struct extended_sigtable)) /* 20 bytes */
102 #define EXT_SIGNATURE_SIZE (sizeof (struct extended_signature)) /* 12 bytes */
103 #define DWSIZE (sizeof (u32))
104 #define get_totalsize(mc) \
105 (((microcode_t *)mc)->hdr.totalsize ? \
106 ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
107 #define get_datasize(mc) \
108 (((microcode_t *)mc)->hdr.datasize ? \
109 ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
111 #define sigmatch(s1, s2, p1, p2) \
112 (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
114 #define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
116 /* serialize access to the physical write to MSR 0x79 */
117 static spinlock_t microcode_update_lock = SPIN_LOCK_UNLOCKED;
119 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
120 static DECLARE_MUTEX(microcode_sem);
122 static void __user *user_buffer; /* user area microcode data buffer */
123 static unsigned int user_buffer_size; /* it's size */
125 typedef enum mc_error_code {
132 static struct ucode_cpu_info {
139 } ucode_cpu_info[NR_CPUS];
141 static int microcode_open (struct inode *unused1, struct file *unused2)
143 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
146 static void collect_cpu_info (void *unused)
148 int cpu_num = smp_processor_id();
149 struct cpuinfo_x86 *c = cpu_data + cpu_num;
150 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
153 uci->sig = uci->pf = uci->rev = uci->cksum = 0;
154 uci->err = MC_NOTFOUND;
157 if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
158 cpu_has(c, X86_FEATURE_IA64)) {
159 printk(KERN_ERR "microcode: CPU%d not a capable Intel processor\n", cpu_num);
162 uci->sig = cpuid_eax(0x00000001);
164 if ((c->x86_model >= 5) || (c->x86 > 6)) {
165 /* get processor flags from MSR 0x17 */
166 rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
167 uci->pf = 1 << ((val[1] >> 18) & 7);
171 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
172 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
173 /* get the current revision from MSR 0x8B */
174 rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
175 dprintk("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
176 uci->sig, uci->pf, uci->rev);
179 static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
181 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
183 dprintk("Microcode Found.\n");
184 dprintk(" Header Revision 0x%x\n", mc_header->hdrver);
185 dprintk(" Loader Revision 0x%x\n", mc_header->ldrver);
186 dprintk(" Revision 0x%x \n", mc_header->rev);
187 dprintk(" Date %x/%x/%x\n",
188 ((mc_header->date >> 24 ) & 0xff),
189 ((mc_header->date >> 16 ) & 0xff),
190 (mc_header->date & 0xFFFF));
191 dprintk(" Signature 0x%x\n", sig);
192 dprintk(" Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
197 dprintk(" Processor Flags 0x%x\n", pf);
198 dprintk(" Checksum 0x%x\n", cksum);
200 if (mc_header->rev < uci->rev) {
201 printk(KERN_ERR "microcode: CPU%d not 'upgrading' to earlier revision"
202 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
204 } else if (mc_header->rev == uci->rev) {
205 /* notify the caller of success on this cpu */
206 uci->err = MC_SUCCESS;
207 printk(KERN_ERR "microcode: CPU%d already at revision"
208 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
212 dprintk("microcode: CPU%d found a matching microcode update with "
213 " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
215 uci->pf = pf; /* keep the original mc pf for cksum calculation */
216 uci->err = MC_MARKED; /* found the match */
221 static int find_matching_ucodes (void)
226 while (cursor + MC_HEADER_SIZE < user_buffer_size) {
227 microcode_header_t mc_header;
229 int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
231 if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
232 printk(KERN_ERR "microcode: error! Can not read user data\n");
237 total_size = get_totalsize(&mc_header);
238 if ((cursor + total_size > user_buffer_size) || (total_size < DEFAULT_UCODE_TOTALSIZE)) {
239 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
244 data_size = get_datasize(&mc_header);
245 if ((data_size + MC_HEADER_SIZE > total_size) || (data_size < DEFAULT_UCODE_DATASIZE)) {
246 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
251 if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
252 printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
257 for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
258 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
259 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
262 if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->pf))
263 mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
266 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
267 if (ext_table_size) {
268 struct extended_sigtable ext_header;
269 struct extended_signature ext_sig;
272 if ((ext_table_size < EXT_HEADER_SIZE)
273 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
274 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
278 if (copy_from_user(&ext_header, user_buffer + cursor
279 + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
280 printk(KERN_ERR "microcode: error! Can not read user data\n");
284 if (ext_table_size != exttable_size(&ext_header)) {
285 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
290 ext_sigcount = ext_header.count;
292 for (i = 0; i < ext_sigcount; i++) {
293 if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE
294 + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
295 printk(KERN_ERR "microcode: error! Can not read user data\n");
299 for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
300 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
301 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
303 if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->pf)) {
304 mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
309 /* now check if any cpu has matched */
310 for (cpu_num = 0, allocated_flag = 0, sum = 0; cpu_num < num_online_cpus(); cpu_num++) {
311 if (ucode_cpu_info[cpu_num].err == MC_MARKED) {
312 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
313 if (!allocated_flag) {
315 newmc = vmalloc(total_size);
317 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
321 if (copy_from_user(newmc + MC_HEADER_SIZE,
322 user_buffer + cursor + MC_HEADER_SIZE,
323 total_size - MC_HEADER_SIZE)) {
324 printk(KERN_ERR "microcode: error! Can not read user data\n");
329 memcpy(newmc, &mc_header, MC_HEADER_SIZE);
330 /* check extended table checksum */
331 if (ext_table_size) {
332 int ext_table_sum = 0;
333 int * ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
334 i = ext_table_size / DWSIZE;
335 while (i--) ext_table_sum += ext_tablep[i];
337 printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
344 /* calculate the checksum */
345 i = (MC_HEADER_SIZE + data_size) / DWSIZE;
346 while (i--) sum += ((int *)newmc)[i];
347 sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
349 ucode_cpu_info[cpu_num].mc = newmc;
350 ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
351 if (sum + uci->sig + uci->pf + uci->cksum != 0) {
352 printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
358 cursor += total_size; /* goto the next update patch */
364 static void do_update_one (void * unused)
368 int cpu_num = smp_processor_id();
369 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
371 if (uci->mc == NULL) {
372 printk(KERN_INFO "microcode: No suitable data for CPU%d\n", cpu_num);
376 /* serialize access to the physical write to MSR 0x79 */
377 spin_lock_irqsave(µcode_update_lock, flags);
379 /* write microcode via MSR 0x79 */
380 wrmsr(MSR_IA32_UCODE_WRITE,
381 (unsigned long) uci->mc->bits,
382 (unsigned long) uci->mc->bits >> 16 >> 16);
383 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
385 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
386 /* get the current revision from MSR 0x8B */
387 rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
389 /* notify the caller of success on this cpu */
390 uci->err = MC_SUCCESS;
391 spin_unlock_irqrestore(µcode_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);
398 static int do_microcode_update (void)
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");
408 if ((error = find_matching_ucodes())) {
409 printk(KERN_ERR "microcode: Error in the microcode data\n");
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");
419 for (i = 0; i < num_online_cpus(); i++) {
420 if (ucode_cpu_info[i].mc) {
422 void *tmp = ucode_cpu_info[i].mc;
424 for (j = i; j < num_online_cpus(); j++) {
425 if (ucode_cpu_info[j].mc == tmp)
426 ucode_cpu_info[j].mc = NULL;
434 static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
438 if (len < DEFAULT_UCODE_TOTALSIZE) {
439 printk(KERN_ERR "microcode: not enough data\n");
443 if ((len >> PAGE_SHIFT) > num_physpages) {
444 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
448 down(µcode_sem);
450 user_buffer = (void __user *) buf;
451 user_buffer_size = (int) len;
453 ret = do_microcode_update();
462 static int microcode_ioctl (struct inode *inode, struct file *file,
463 unsigned int cmd, unsigned long arg)
467 * XXX: will be removed after microcode_ctl
468 * is updated to ignore failure of this ioctl()
470 case MICROCODE_IOCFREE:
478 static struct file_operations microcode_fops = {
479 .owner = THIS_MODULE,
480 .write = microcode_write,
481 .ioctl = microcode_ioctl,
482 .open = microcode_open,
485 static struct miscdevice microcode_dev = {
486 .minor = MICROCODE_MINOR,
488 .devfs_name = "cpu/microcode",
489 .fops = µcode_fops,
492 static int __init microcode_init (void)
496 error = misc_register(µcode_dev);
499 "microcode: can't misc_register on minor=%d\n",
505 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
509 static void __exit microcode_exit (void)
511 misc_deregister(µcode_dev);
512 printk(KERN_INFO "IA-32 Microcode Update Driver v" MICROCODE_VERSION " unregistered\n");
515 module_init(microcode_init)
516 module_exit(microcode_exit)
517 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);