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
59 * speculative 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 "2.00"
104 struct microcode_ops *microcode_ops;
106 /* no concurrent ->write()s are allowed on /dev/cpu/microcode */
107 DEFINE_MUTEX(microcode_mutex);
108 EXPORT_SYMBOL_GPL(microcode_mutex);
110 struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
111 EXPORT_SYMBOL_GPL(ucode_cpu_info);
113 #ifdef CONFIG_MICROCODE_OLD_INTERFACE
114 void __user *user_buffer; /* user area microcode data buffer */
115 EXPORT_SYMBOL_GPL(user_buffer);
116 unsigned int user_buffer_size; /* it's size */
117 EXPORT_SYMBOL_GPL(user_buffer_size);
119 static int do_microcode_update(void)
127 old = current->cpus_allowed;
129 while ((cursor = microcode_ops->get_next_ucode(&new_mc, cursor)) > 0) {
130 if (microcode_ops->microcode_sanity_check != NULL)
131 error = microcode_ops->microcode_sanity_check(new_mc);
135 * It's possible the data file has multiple matching ucode,
136 * lets keep searching till the latest version
138 for_each_online_cpu(cpu) {
139 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
143 set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
144 error = microcode_ops->get_matching_microcode(new_mc,
149 microcode_ops->apply_microcode(cpu);
158 set_cpus_allowed_ptr(current, &old);
162 static int microcode_open(struct inode *unused1, struct file *unused2)
165 return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
168 static ssize_t microcode_write(struct file *file, const char __user *buf,
169 size_t len, loff_t *ppos)
173 if ((len >> PAGE_SHIFT) > num_physpages) {
174 printk(KERN_ERR "microcode: too much data (max %ld pages)\n",
180 mutex_lock(µcode_mutex);
182 user_buffer = (void __user *) buf;
183 user_buffer_size = (int) len;
185 ret = do_microcode_update();
189 mutex_unlock(µcode_mutex);
195 static const struct file_operations microcode_fops = {
196 .owner = THIS_MODULE,
197 .write = microcode_write,
198 .open = microcode_open,
201 static struct miscdevice microcode_dev = {
202 .minor = MICROCODE_MINOR,
204 .fops = µcode_fops,
207 static int __init microcode_dev_init(void)
211 error = misc_register(µcode_dev);
214 "microcode: can't misc_register on minor=%d\n",
222 static void microcode_dev_exit(void)
224 misc_deregister(µcode_dev);
227 MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
229 #define microcode_dev_init() 0
230 #define microcode_dev_exit() do { } while (0)
233 /* fake device for request_firmware */
234 struct platform_device *microcode_pdev;
235 EXPORT_SYMBOL_GPL(microcode_pdev);
237 static void microcode_init_cpu(int cpu, int resume)
240 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
242 old = current->cpus_allowed;
244 set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
245 mutex_lock(µcode_mutex);
246 microcode_ops->collect_cpu_info(cpu);
247 if (uci->valid && system_state == SYSTEM_RUNNING && !resume)
248 microcode_ops->cpu_request_microcode(cpu);
249 mutex_unlock(µcode_mutex);
250 set_cpus_allowed_ptr(current, &old);
253 static ssize_t reload_store(struct sys_device *dev,
254 struct sysdev_attribute *attr,
255 const char *buf, size_t sz)
257 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
259 unsigned long val = simple_strtoul(buf, &end, 0);
266 cpumask_t old = current->cpus_allowed;
269 set_cpus_allowed_ptr(current, &cpumask_of_cpu(cpu));
271 mutex_lock(µcode_mutex);
273 err = microcode_ops->cpu_request_microcode(cpu);
274 mutex_unlock(µcode_mutex);
276 set_cpus_allowed_ptr(current, &old);
283 static ssize_t version_show(struct sys_device *dev,
284 struct sysdev_attribute *attr, char *buf)
286 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
288 return sprintf(buf, "0x%x\n", uci->rev);
291 static ssize_t pf_show(struct sys_device *dev,
292 struct sysdev_attribute *attr, char *buf)
294 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
296 return sprintf(buf, "0x%x\n", uci->pf);
299 static SYSDEV_ATTR(reload, 0200, NULL, reload_store);
300 static SYSDEV_ATTR(version, 0400, version_show, NULL);
301 static SYSDEV_ATTR(processor_flags, 0400, pf_show, NULL);
303 static struct attribute *mc_default_attrs[] = {
306 &attr_processor_flags.attr,
310 static struct attribute_group mc_attr_group = {
311 .attrs = mc_default_attrs,
315 static int __mc_sysdev_add(struct sys_device *sys_dev, int resume)
317 int err, cpu = sys_dev->id;
318 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
320 if (!cpu_online(cpu))
323 pr_debug("microcode: CPU%d added\n", cpu);
324 memset(uci, 0, sizeof(*uci));
326 err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group);
330 microcode_init_cpu(cpu, resume);
335 static int mc_sysdev_add(struct sys_device *sys_dev)
337 return __mc_sysdev_add(sys_dev, 0);
340 static int mc_sysdev_remove(struct sys_device *sys_dev)
342 int cpu = sys_dev->id;
344 if (!cpu_online(cpu))
347 pr_debug("microcode: CPU%d removed\n", cpu);
348 microcode_ops->microcode_fini_cpu(cpu);
349 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
353 static int mc_sysdev_resume(struct sys_device *dev)
357 if (!cpu_online(cpu))
359 pr_debug("microcode: CPU%d resumed\n", cpu);
360 /* only CPU 0 will apply ucode here */
361 microcode_ops->apply_microcode(0);
365 static struct sysdev_driver mc_sysdev_driver = {
366 .add = mc_sysdev_add,
367 .remove = mc_sysdev_remove,
368 .resume = mc_sysdev_resume,
372 mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
374 unsigned int cpu = (unsigned long)hcpu;
375 struct sys_device *sys_dev;
377 sys_dev = get_cpu_sysdev(cpu);
379 case CPU_UP_CANCELED_FROZEN:
380 /* The CPU refused to come up during a system resume */
381 microcode_ops->microcode_fini_cpu(cpu);
384 case CPU_DOWN_FAILED:
385 mc_sysdev_add(sys_dev);
387 case CPU_ONLINE_FROZEN:
388 /* System-wide resume is in progress, try to apply microcode */
389 if (microcode_ops->apply_microcode_check_cpu(cpu)) {
390 /* The application of microcode failed */
391 microcode_ops->microcode_fini_cpu(cpu);
392 __mc_sysdev_add(sys_dev, 1);
395 case CPU_DOWN_FAILED_FROZEN:
396 if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group))
397 printk(KERN_ERR "microcode: Failed to create the sysfs "
398 "group for CPU%d\n", cpu);
400 case CPU_DOWN_PREPARE:
401 mc_sysdev_remove(sys_dev);
403 case CPU_DOWN_PREPARE_FROZEN:
404 /* Suspend is in progress, only remove the interface */
405 sysfs_remove_group(&sys_dev->kobj, &mc_attr_group);
411 static struct notifier_block __refdata mc_cpu_notifier = {
412 .notifier_call = mc_cpu_callback,
415 int microcode_init(void *opaque, struct module *module)
417 struct microcode_ops *ops = (struct microcode_ops *)opaque;
421 printk(KERN_ERR "microcode: already loaded the other module\n");
427 error = microcode_dev_init();
430 microcode_pdev = platform_device_register_simple("microcode", -1,
432 if (IS_ERR(microcode_pdev)) {
433 microcode_dev_exit();
434 return PTR_ERR(microcode_pdev);
438 error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver);
441 microcode_dev_exit();
442 platform_device_unregister(microcode_pdev);
446 register_hotcpu_notifier(&mc_cpu_notifier);
449 "Microcode Update Driver: v" MICROCODE_VERSION
450 " <tigran@aivazian.fsnet.co.uk>"
451 " <peter.oruba@amd.com>\n");
455 EXPORT_SYMBOL_GPL(microcode_init);
457 void __exit microcode_exit(void)
459 microcode_dev_exit();
461 unregister_hotcpu_notifier(&mc_cpu_notifier);
464 sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver);
467 platform_device_unregister(microcode_pdev);
469 microcode_ops = NULL;
472 "Microcode Update Driver: v" MICROCODE_VERSION " removed.\n");
474 EXPORT_SYMBOL_GPL(microcode_exit);