2 * Intel CPU Microcode Update Driver for Linux
4 * Copyright (C) 2000-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
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 8.11 of Volume 3a, IA-32 Intel? Architecture
12 * Software Developer's Manual
13 * Order Number 253668 or free download from:
15 * http://developer.intel.com/design/pentium4/manuals/253668.htm
17 * For more information, go to http://www.urbanmyth.org/microcode
19 * This program is free software; you can redistribute it and/or
20 * modify it under the terms of the GNU General Public License
21 * as published by the Free Software Foundation; either version
22 * 2 of the License, or (at your option) any later version.
24 * 1.0 16 Feb 2000, Tigran Aivazian <tigran@sco.com>
26 * 1.01 18 Feb 2000, Tigran Aivazian <tigran@sco.com>
27 * Added read() support + cleanups.
28 * 1.02 21 Feb 2000, Tigran Aivazian <tigran@sco.com>
29 * Added 'device trimming' support. open(O_WRONLY) zeroes
30 * and frees the saved copy of applied microcode.
31 * 1.03 29 Feb 2000, Tigran Aivazian <tigran@sco.com>
32 * Made to use devfs (/dev/cpu/microcode) + cleanups.
33 * 1.04 06 Jun 2000, Simon Trimmer <simon@veritas.com>
34 * Added misc device support (now uses both devfs and misc).
35 * Added MICROCODE_IOCFREE ioctl to clear memory.
36 * 1.05 09 Jun 2000, Simon Trimmer <simon@veritas.com>
37 * Messages for error cases (non Intel & no suitable microcode).
38 * 1.06 03 Aug 2000, Tigran Aivazian <tigran@veritas.com>
39 * Removed ->release(). Removed exclusive open and status bitmap.
40 * Added microcode_rwsem to serialize read()/write()/ioctl().
41 * Removed global kernel lock usage.
42 * 1.07 07 Sep 2000, Tigran Aivazian <tigran@veritas.com>
43 * Write 0 to 0x8B msr and then cpuid before reading revision,
44 * so that it works even if there were no update done by the
45 * BIOS. Otherwise, reading from 0x8B gives junk (which happened
46 * to be 0 on my machine which is why it worked even when I
47 * disabled update by the BIOS)
48 * Thanks to Eric W. Biederman <ebiederman@lnxi.com> for the fix.
49 * 1.08 11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and
50 * Tigran Aivazian <tigran@veritas.com>
51 * Intel Pentium 4 processor support and bugfixes.
52 * 1.09 30 Oct 2001, Tigran Aivazian <tigran@veritas.com>
53 * Bugfix for HT (Hyper-Threading) enabled processors
54 * whereby processor resources are shared by all logical processors
55 * in a single CPU package.
56 * 1.10 28 Feb 2002 Asit K Mallick <asit.k.mallick@intel.com> and
57 * Tigran Aivazian <tigran@veritas.com>,
58 * Serialize updates as required on HT processors due to speculative
59 * nature of implementation.
60 * 1.11 22 Mar 2002 Tigran Aivazian <tigran@veritas.com>
61 * Fix the panic when writing zero-length microcode chunk.
62 * 1.12 29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>,
63 * Jun Nakajima <jun.nakajima@intel.com>
64 * Support for the microcode updates in the new format.
65 * 1.13 10 Oct 2003 Tigran Aivazian <tigran@veritas.com>
66 * Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl
67 * because we no longer hold a copy of applied microcode
69 * 1.14 25 Jun 2004 Tigran Aivazian <tigran@veritas.com>
70 * Fix sigmatch() macro to handle old CPUs with pf == 0.
71 * Thanks to Stuart Swales for pointing out this bug.
74 //#define DEBUG /* pr_debug */
75 #include <linux/capability.h>
76 #include <linux/kernel.h>
77 #include <linux/init.h>
78 #include <linux/sched.h>
79 #include <linux/smp_lock.h>
80 #include <linux/cpumask.h>
81 #include <linux/module.h>
82 #include <linux/slab.h>
83 #include <linux/vmalloc.h>
84 #include <linux/miscdevice.h>
85 #include <linux/spinlock.h>
88 #include <linux/mutex.h>
89 #include <linux/cpu.h>
90 #include <linux/firmware.h>
91 #include <linux/platform_device.h>
94 #include <asm/uaccess.h>
95 #include <asm/processor.h>
96 #include <asm/microcode.h>
98 MODULE_DESCRIPTION("Microcode Update Driver");
99 MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
100 MODULE_LICENSE("GPL");
102 #define MICROCODE_VERSION "1.14a"
104 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
105 DEFINE_MUTEX(microcode_mutex);
107 struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
109 extern long get_next_ucode(void **mc, long offset);
110 extern int microcode_sanity_check(void *mc);
111 extern int get_matching_microcode(void *mc, int cpu);
112 extern void collect_cpu_info(int cpu_num);
113 extern int cpu_request_microcode(int cpu);
114 extern void microcode_fini_cpu(int cpu);
115 extern void apply_microcode(int cpu);
116 extern int apply_microcode_check_cpu(int cpu);
118 #ifdef CONFIG_MICROCODE_OLD_INTERFACE
119 void __user *user_buffer; /* user area microcode data buffer */
120 unsigned int user_buffer_size; /* it's size */
122 static int do_microcode_update (void)
129 cpumask_of_cpu_ptr_declare(newmask);
131 old = current->cpus_allowed;
133 while ((cursor = get_next_ucode(&new_mc, cursor)) > 0) {
134 error = microcode_sanity_check(new_mc);
138 * It's possible the data file has multiple matching ucode,
139 * lets keep searching till the latest version
141 for_each_online_cpu(cpu) {
142 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
146 cpumask_of_cpu_ptr_next(newmask, cpu);
147 set_cpus_allowed_ptr(current, newmask);
148 error = get_maching_microcode(new_mc, cpu);
152 apply_microcode(cpu);
161 set_cpus_allowed_ptr(current, &old);
165 static int microcode_open (struct inode *unused1, struct file *unused2)
168 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
171 static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
175 if ((len >> PAGE_SHIFT) > num_physpages) {
176 printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
181 mutex_lock(µcode_mutex);
183 user_buffer = (void __user *) buf;
184 user_buffer_size = (int) len;
186 ret = do_microcode_update();
190 mutex_unlock(µcode_mutex);
196 static const struct file_operations microcode_fops = {
197 .owner = THIS_MODULE,
198 .write = microcode_write,
199 .open = microcode_open,
202 static struct miscdevice microcode_dev = {
203 .minor = MICROCODE_MINOR,
205 .fops = µcode_fops,
208 static int __init microcode_dev_init (void)
212 error = misc_register(µcode_dev);
215 "microcode: can't misc_register on minor=%d\n",
223 static void microcode_dev_exit (void)
225 misc_deregister(µcode_dev);
228 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
230 #define microcode_dev_init() 0
231 #define microcode_dev_exit() do { } while(0)
234 /* fake device for request_firmware */
235 struct platform_device *microcode_pdev;
237 static void microcode_init_cpu(int cpu, int resume)
240 cpumask_of_cpu_ptr(newmask, cpu);
241 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
243 old = current->cpus_allowed;
245 set_cpus_allowed_ptr(current, newmask);
246 mutex_lock(µcode_mutex);
247 collect_cpu_info(cpu);
248 if (uci->valid && system_state == SYSTEM_RUNNING && !resume)
249 cpu_request_microcode(cpu);
250 mutex_unlock(µcode_mutex);
251 set_cpus_allowed_ptr(current, &old);
254 static ssize_t reload_store(struct sys_device *dev,
255 struct sysdev_attribute *attr,
256 const char *buf, size_t sz)
258 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
260 unsigned long val = simple_strtoul(buf, &end, 0);
268 cpumask_of_cpu_ptr(newmask, cpu);
270 old = current->cpus_allowed;
273 set_cpus_allowed_ptr(current, newmask);
275 mutex_lock(µcode_mutex);
277 err = cpu_request_microcode(cpu);
278 mutex_unlock(µcode_mutex);
280 set_cpus_allowed_ptr(current, &old);
287 static ssize_t version_show(struct sys_device *dev,
288 struct sysdev_attribute *attr, char *buf)
290 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
292 return sprintf(buf, "0x%x\n", uci->rev);
295 static ssize_t pf_show(struct sys_device *dev,
296 struct sysdev_attribute *attr, char *buf)
298 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
300 return sprintf(buf, "0x%x\n", uci->pf);
303 static SYSDEV_ATTR(reload, 0200, NULL, reload_store);
304 static SYSDEV_ATTR(version, 0400, version_show, NULL);
305 static SYSDEV_ATTR(processor_flags, 0400, pf_show, NULL);
307 static struct attribute *mc_default_attrs[] = {
310 &attr_processor_flags.attr,
314 static struct attribute_group mc_attr_group = {
315 .attrs = mc_default_attrs,
319 static int __mc_sysdev_add(struct sys_device *sys_dev, int resume)
321 int err, cpu = sys_dev->id;
322 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
324 if (!cpu_online(cpu))
327 pr_debug("microcode: CPU%d added\n", cpu);
328 memset(uci, 0, sizeof(*uci));
330 err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group);
334 microcode_init_cpu(cpu, resume);
339 static int mc_sysdev_add(struct sys_device *sys_dev)
341 return __mc_sysdev_add(sys_dev, 0);
344 static int mc_sysdev_remove(struct sys_device *sys_dev)
346 int cpu = sys_dev->id;
348 if (!cpu_online(cpu))
351 pr_debug("microcode: CPU%d removed\n", cpu);
352 microcode_fini_cpu(cpu);
353 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
357 static int mc_sysdev_resume(struct sys_device *dev)
361 if (!cpu_online(cpu))
363 pr_debug("microcode: CPU%d resumed\n", cpu);
364 /* only CPU 0 will apply ucode here */
369 static struct sysdev_driver mc_sysdev_driver = {
370 .add = mc_sysdev_add,
371 .remove = mc_sysdev_remove,
372 .resume = mc_sysdev_resume,
376 mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
378 unsigned int cpu = (unsigned long)hcpu;
379 struct sys_device *sys_dev;
381 sys_dev = get_cpu_sysdev(cpu);
383 case CPU_UP_CANCELED_FROZEN:
384 /* The CPU refused to come up during a system resume */
385 microcode_fini_cpu(cpu);
388 case CPU_DOWN_FAILED:
389 mc_sysdev_add(sys_dev);
391 case CPU_ONLINE_FROZEN:
392 /* System-wide resume is in progress, try to apply microcode */
393 if (apply_microcode_check_cpu(cpu)) {
394 /* The application of microcode failed */
395 microcode_fini_cpu(cpu);
396 __mc_sysdev_add(sys_dev, 1);
399 case CPU_DOWN_FAILED_FROZEN:
400 if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group))
401 printk(KERN_ERR "microcode: Failed to create the sysfs "
402 "group for CPU%d\n", cpu);
404 case CPU_DOWN_PREPARE:
405 mc_sysdev_remove(sys_dev);
407 case CPU_DOWN_PREPARE_FROZEN:
408 /* Suspend is in progress, only remove the interface */
409 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
415 static struct notifier_block __refdata mc_cpu_notifier = {
416 .notifier_call = mc_cpu_callback,
419 static int __init microcode_init (void)
424 "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@aivazian.fsnet.co.uk>\n");
426 error = microcode_dev_init();
429 microcode_pdev = platform_device_register_simple("microcode", -1,
431 if (IS_ERR(microcode_pdev)) {
432 microcode_dev_exit();
433 return PTR_ERR(microcode_pdev);
437 error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver);
440 microcode_dev_exit();
441 platform_device_unregister(microcode_pdev);
445 register_hotcpu_notifier(&mc_cpu_notifier);
449 static void __exit microcode_exit (void)
451 microcode_dev_exit();
453 unregister_hotcpu_notifier(&mc_cpu_notifier);
456 sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver);
459 platform_device_unregister(microcode_pdev);
462 module_init(microcode_init)
463 module_exit(microcode_exit)