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 23 Feb 2004 Tigran Aivazian <tigran@veritas.com>
68 * Restored devfs regular file entry point which was
69 * accidentally removed when back-porting changes from the 2.6
70 * version of the driver.
74 #include <linux/init.h>
75 #include <linux/sched.h>
76 #include <linux/module.h>
77 #include <linux/slab.h>
78 #include <linux/vmalloc.h>
79 #include <linux/miscdevice.h>
80 #include <linux/devfs_fs_kernel.h>
81 #include <linux/spinlock.h>
85 #include <asm/uaccess.h>
86 #include <asm/processor.h>
88 MODULE_DESCRIPTION("Intel CPU (IA-32) microcode update driver");
89 MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
90 MODULE_LICENSE("GPL");
92 #define MICROCODE_VERSION "1.14"
95 #define dprintk(x...) printk(KERN_INFO x)
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 spinlock_t microcode_update_lock = SPIN_LOCK_UNLOCKED;
121 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
122 static DECLARE_MUTEX(microcode_sem);
124 static void *user_buffer; /* user area microcode data buffer */
125 static unsigned int user_buffer_size; /* it's size */
127 typedef enum mc_error_code {
134 static struct ucode_cpu_info {
141 } ucode_cpu_info[NR_CPUS];
143 static int microcode_open (struct inode *unused1, struct file *unused2)
145 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
148 static void collect_cpu_info (void *unused)
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;
155 uci->sig = uci->pf = uci->rev = uci->cksum = 0;
156 uci->err = MC_NOTFOUND;
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);
164 uci->sig = cpuid_eax(0x00000001);
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);
173 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
174 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
175 /* get the current revision from MSR 0x8B */
176 rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
177 dprintk("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
178 uci->sig, uci->pf, uci->rev);
181 static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
183 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
185 dprintk("Microcode Found.\n");
186 dprintk(" Header Revision 0x%x\n", mc_header->hdrver);
187 dprintk(" Loader Revision 0x%x\n", mc_header->ldrver);
188 dprintk(" Revision 0x%x \n", mc_header->rev);
189 dprintk(" Date %x/%x/%x\n",
190 ((mc_header->date >> 24 ) & 0xff),
191 ((mc_header->date >> 16 ) & 0xff),
192 (mc_header->date & 0xFFFF));
193 dprintk(" Signature 0x%x\n", sig);
194 dprintk(" Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
199 dprintk(" Processor Flags 0x%x\n", pf);
200 dprintk(" Checksum 0x%x\n", cksum);
202 if (mc_header->rev < uci->rev) {
203 printk(KERN_ERR "microcode: CPU%d not 'upgrading' to earlier revision"
204 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
206 } else if (mc_header->rev == uci->rev) {
207 /* notify the caller of success on this cpu */
208 uci->err = MC_SUCCESS;
209 printk(KERN_ERR "microcode: CPU%d already at revision"
210 " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
214 dprintk("microcode: CPU%d found a matching microcode update with "
215 " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
217 uci->pf = pf; /* keep the original mc pf for cksum calculation */
218 uci->err = MC_MARKED; /* found the match */
223 static int find_matching_ucodes (void)
228 while (cursor + MC_HEADER_SIZE < user_buffer_size) {
229 microcode_header_t mc_header;
231 int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
233 if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
234 printk(KERN_ERR "microcode: error! Can not read user data\n");
239 total_size = get_totalsize(&mc_header);
240 if (cursor + total_size > user_buffer_size) {
241 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
246 data_size = get_datasize(&mc_header);
247 if (data_size + MC_HEADER_SIZE > total_size) {
248 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
253 if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
254 printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
259 for (cpu_num = 0; cpu_num < smp_num_cpus; cpu_num++) {
260 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
261 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
264 if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->pf))
265 mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
268 ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
269 if (ext_table_size) {
270 struct extended_sigtable ext_header;
271 struct extended_signature ext_sig;
274 if ((ext_table_size < EXT_HEADER_SIZE)
275 || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
276 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
280 if (copy_from_user(&ext_header, user_buffer + cursor
281 + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
282 printk(KERN_ERR "microcode: error! Can not read user data\n");
286 if (ext_table_size != exttable_size(&ext_header)) {
287 printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
292 ext_sigcount = ext_header.count;
294 for (i = 0; i < ext_sigcount; i++) {
295 if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE
296 + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
297 printk(KERN_ERR "microcode: error! Can not read user data\n");
301 for (cpu_num = 0; cpu_num < smp_num_cpus; cpu_num++) {
302 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
303 if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
305 if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->pf)) {
306 mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
311 /* now check if any cpu has matched */
312 for (cpu_num = 0, allocated_flag = 0, sum = 0; cpu_num < smp_num_cpus; cpu_num++) {
313 if (ucode_cpu_info[cpu_num].err == MC_MARKED) {
314 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
315 if (!allocated_flag) {
317 newmc = vmalloc(total_size);
319 printk(KERN_ERR "microcode: error! Can not allocate memory\n");
323 if (copy_from_user(newmc + MC_HEADER_SIZE,
324 user_buffer + cursor + MC_HEADER_SIZE,
325 total_size - MC_HEADER_SIZE)) {
326 printk(KERN_ERR "microcode: error! Can not read user data\n");
331 memcpy(newmc, &mc_header, MC_HEADER_SIZE);
332 /* check extended table checksum */
333 if (ext_table_size) {
335 int ext_table_sum = 0;
336 i = ext_table_size / DWSIZE;
337 ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
338 while (i--) ext_table_sum += ext_tablep[i];
340 printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
347 /* calculate the checksum */
348 i = (MC_HEADER_SIZE + data_size) / DWSIZE;
349 while (i--) sum += ((int *)newmc)[i];
350 sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
352 ucode_cpu_info[cpu_num].mc = newmc;
353 ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
354 if (sum + uci->sig + uci->pf + uci->cksum != 0) {
355 printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
361 cursor += total_size; /* goto the next update patch */
367 static void do_update_one (void * unused)
371 int cpu_num = smp_processor_id();
372 struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
374 if (uci->mc == NULL) {
375 printk(KERN_INFO "microcode: No suitable data for cpu %d\n", cpu_num);
379 /* serialize access to the physical write to MSR 0x79 */
380 spin_lock_irqsave(µcode_update_lock, flags);
382 /* write microcode via MSR 0x79 */
383 wrmsr(MSR_IA32_UCODE_WRITE, (unsigned int)(uci->mc->bits), 0);
384 wrmsr(MSR_IA32_UCODE_REV, 0, 0);
386 __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
387 /* get the current revision from MSR 0x8B */
388 rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
390 /* notify the caller of success on this cpu */
391 uci->err = MC_SUCCESS;
392 spin_unlock_irqrestore(µcode_update_lock, flags);
393 printk(KERN_INFO "microcode: CPU%d updated from revision "
394 "0x%x to 0x%x, date = %08x \n",
395 cpu_num, uci->rev, val[1], uci->mc->hdr.date);
399 static int do_microcode_update (void)
403 if (smp_call_function(collect_cpu_info, NULL, 1, 1) != 0) {
404 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
408 collect_cpu_info(NULL);
410 if ((error = find_matching_ucodes())) {
411 printk(KERN_ERR "microcode: Error in the microcode data\n");
415 if (smp_call_function(do_update_one, NULL, 1, 1) != 0) {
416 printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
422 for (i = 0; i < smp_num_cpus; i++) {
423 if (ucode_cpu_info[i].mc) {
425 void *tmp = ucode_cpu_info[i].mc;
427 for (j = i; j < smp_num_cpus; j++) {
428 if (ucode_cpu_info[j].mc == tmp)
429 ucode_cpu_info[j].mc = NULL;
437 static ssize_t microcode_write (struct file *file, const char *buf, size_t len, loff_t *ppos)
441 if ((len >> PAGE_SHIFT) > num_physpages) {
442 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
446 down(µcode_sem);
448 user_buffer = (void *) buf;
449 user_buffer_size = (int) len;
451 ret = do_microcode_update();
460 static int microcode_ioctl (struct inode *inode, struct file *file,
461 unsigned int cmd, unsigned long arg)
465 * XXX: will be removed after microcode_ctl
466 * is updated to ignore failure of this ioctl()
468 case MICROCODE_IOCFREE:
476 /* shared between misc device and devfs regular file */
477 static struct file_operations microcode_fops = {
478 .owner = THIS_MODULE,
479 .write = microcode_write,
480 .ioctl = microcode_ioctl,
481 .open = microcode_open,
484 static struct miscdevice microcode_dev = {
485 .minor = MICROCODE_MINOR,
487 .fops = µcode_fops,
490 static devfs_handle_t devfs_handle;
492 static int __init microcode_init (void)
496 error = misc_register(µcode_dev);
499 "microcode: can't misc_register on minor=%d\n",
501 devfs_handle = devfs_register(NULL, "cpu/microcode",
502 DEVFS_FL_DEFAULT, 0, 0, S_IFREG | S_IRUSR | S_IWUSR,
503 µcode_fops, NULL);
504 if (devfs_handle == NULL && error) {
505 printk(KERN_ERR "microcode: failed to devfs_register()\n");
510 "IA-32 Microcode Update Driver: v"
511 MICROCODE_VERSION " <tigran@veritas.com>\n");
516 static void __exit microcode_exit (void)
518 misc_deregister(µcode_dev);
519 devfs_unregister(devfs_handle);
520 printk(KERN_INFO "IA-32 Microcode Update Driver v"
521 MICROCODE_VERSION " unregistered\n");
524 module_init(microcode_init)
525 module_exit(microcode_exit)