/* * Intel CPU Microcode Update Driver for Linux * * Copyright (C) 2000-2006 Tigran Aivazian * 2006 Shaohua Li * * This driver allows to upgrade microcode on Intel processors * belonging to IA-32 family - PentiumPro, Pentium II, * Pentium III, Xeon, Pentium 4, etc. * * Reference: Section 8.11 of Volume 3a, IA-32 Intel? Architecture * Software Developer's Manual * Order Number 253668 or free download from: * * http://developer.intel.com/design/pentium4/manuals/253668.htm * * For more information, go to http://www.urbanmyth.org/microcode * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * 1.0 16 Feb 2000, Tigran Aivazian * Initial release. * 1.01 18 Feb 2000, Tigran Aivazian * Added read() support + cleanups. * 1.02 21 Feb 2000, Tigran Aivazian * Added 'device trimming' support. open(O_WRONLY) zeroes * and frees the saved copy of applied microcode. * 1.03 29 Feb 2000, Tigran Aivazian * Made to use devfs (/dev/cpu/microcode) + cleanups. * 1.04 06 Jun 2000, Simon Trimmer * Added misc device support (now uses both devfs and misc). * Added MICROCODE_IOCFREE ioctl to clear memory. * 1.05 09 Jun 2000, Simon Trimmer * Messages for error cases (non Intel & no suitable microcode). * 1.06 03 Aug 2000, Tigran Aivazian * Removed ->release(). Removed exclusive open and status bitmap. * Added microcode_rwsem to serialize read()/write()/ioctl(). * Removed global kernel lock usage. * 1.07 07 Sep 2000, Tigran Aivazian * Write 0 to 0x8B msr and then cpuid before reading revision, * so that it works even if there were no update done by the * BIOS. Otherwise, reading from 0x8B gives junk (which happened * to be 0 on my machine which is why it worked even when I * disabled update by the BIOS) * Thanks to Eric W. Biederman for the fix. * 1.08 11 Dec 2000, Richard Schaal and * Tigran Aivazian * Intel Pentium 4 processor support and bugfixes. * 1.09 30 Oct 2001, Tigran Aivazian * Bugfix for HT (Hyper-Threading) enabled processors * whereby processor resources are shared by all logical processors * in a single CPU package. * 1.10 28 Feb 2002 Asit K Mallick and * Tigran Aivazian , * Serialize updates as required on HT processors due to * speculative nature of implementation. * 1.11 22 Mar 2002 Tigran Aivazian * Fix the panic when writing zero-length microcode chunk. * 1.12 29 Sep 2003 Nitin Kamble , * Jun Nakajima * Support for the microcode updates in the new format. * 1.13 10 Oct 2003 Tigran Aivazian * Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl * because we no longer hold a copy of applied microcode * in kernel memory. * 1.14 25 Jun 2004 Tigran Aivazian * Fix sigmatch() macro to handle old CPUs with pf == 0. * Thanks to Stuart Swales for pointing out this bug. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include MODULE_DESCRIPTION("Microcode Update Driver"); MODULE_AUTHOR("Tigran Aivazian "); MODULE_LICENSE("GPL"); #define MICROCODE_VERSION "2.00" static struct microcode_ops *microcode_ops; /* no concurrent ->write()s are allowed on /dev/cpu/microcode */ static DEFINE_MUTEX(microcode_mutex); struct ucode_cpu_info ucode_cpu_info[NR_CPUS]; EXPORT_SYMBOL_GPL(ucode_cpu_info); #ifdef CONFIG_MICROCODE_OLD_INTERFACE struct update_for_cpu { const void __user *buf; size_t size; }; static long update_for_cpu(void *_ufc) { struct update_for_cpu *ufc = _ufc; int error; error = microcode_ops->request_microcode_user(smp_processor_id(), ufc->buf, ufc->size); if (error < 0) return error; if (!error) microcode_ops->apply_microcode(smp_processor_id()); return error; } static int do_microcode_update(const void __user *buf, size_t size) { int error = 0; int cpu; struct update_for_cpu ufc = { .buf = buf, .size = size }; for_each_online_cpu(cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (!uci->valid) continue; error = work_on_cpu(cpu, update_for_cpu, &ufc); if (error < 0) break; } return error; } static int microcode_open(struct inode *unused1, struct file *unused2) { cycle_kernel_lock(); return capable(CAP_SYS_RAWIO) ? 0 : -EPERM; } static ssize_t microcode_write(struct file *file, const char __user *buf, size_t len, loff_t *ppos) { ssize_t ret; if ((len >> PAGE_SHIFT) > num_physpages) { printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages); return -EINVAL; } get_online_cpus(); mutex_lock(µcode_mutex); ret = do_microcode_update(buf, len); if (!ret) ret = (ssize_t)len; mutex_unlock(µcode_mutex); put_online_cpus(); return ret; } static const struct file_operations microcode_fops = { .owner = THIS_MODULE, .write = microcode_write, .open = microcode_open, }; static struct miscdevice microcode_dev = { .minor = MICROCODE_MINOR, .name = "microcode", .fops = µcode_fops, }; static int __init microcode_dev_init(void) { int error; error = misc_register(µcode_dev); if (error) { printk(KERN_ERR "microcode: can't misc_register on minor=%d\n", MICROCODE_MINOR); return error; } return 0; } static void microcode_dev_exit(void) { misc_deregister(µcode_dev); } MODULE_ALIAS_MISCDEV(MICROCODE_MINOR); #else #define microcode_dev_init() 0 #define microcode_dev_exit() do { } while (0) #endif /* fake device for request_firmware */ static struct platform_device *microcode_pdev; static long reload_for_cpu(void *unused) { struct ucode_cpu_info *uci = ucode_cpu_info + smp_processor_id(); int err = 0; mutex_lock(µcode_mutex); if (uci->valid) { err = microcode_ops->request_microcode_fw(smp_processor_id(), µcode_pdev->dev); if (!err) microcode_ops->apply_microcode(smp_processor_id()); } mutex_unlock(µcode_mutex); return err; } static ssize_t reload_store(struct sys_device *dev, struct sysdev_attribute *attr, const char *buf, size_t sz) { char *end; unsigned long val = simple_strtoul(buf, &end, 0); int err = 0; int cpu = dev->id; if (end == buf) return -EINVAL; if (val == 1) { get_online_cpus(); if (cpu_online(cpu)) err = work_on_cpu(cpu, reload_for_cpu, NULL); put_online_cpus(); } if (err) return err; return sz; } static ssize_t version_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct ucode_cpu_info *uci = ucode_cpu_info + dev->id; return sprintf(buf, "0x%x\n", uci->cpu_sig.rev); } static ssize_t pf_show(struct sys_device *dev, struct sysdev_attribute *attr, char *buf) { struct ucode_cpu_info *uci = ucode_cpu_info + dev->id; return sprintf(buf, "0x%x\n", uci->cpu_sig.pf); } static SYSDEV_ATTR(reload, 0200, NULL, reload_store); static SYSDEV_ATTR(version, 0400, version_show, NULL); static SYSDEV_ATTR(processor_flags, 0400, pf_show, NULL); static struct attribute *mc_default_attrs[] = { &attr_reload.attr, &attr_version.attr, &attr_processor_flags.attr, NULL }; static struct attribute_group mc_attr_group = { .attrs = mc_default_attrs, .name = "microcode", }; static void __microcode_fini_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; microcode_ops->microcode_fini_cpu(cpu); uci->valid = 0; } static void microcode_fini_cpu(int cpu) { mutex_lock(µcode_mutex); __microcode_fini_cpu(cpu); mutex_unlock(µcode_mutex); } static void collect_cpu_info(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; memset(uci, 0, sizeof(*uci)); if (!microcode_ops->collect_cpu_info(cpu, &uci->cpu_sig)) uci->valid = 1; } static int microcode_resume_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; struct cpu_signature nsig; pr_debug("microcode: CPU%d resumed\n", cpu); if (!uci->mc) return 1; /* * Let's verify that the 'cached' ucode does belong * to this cpu (a bit of paranoia): */ if (microcode_ops->collect_cpu_info(cpu, &nsig)) { __microcode_fini_cpu(cpu); printk(KERN_ERR "failed to collect_cpu_info for resuming cpu #%d\n", cpu); return -1; } if ((nsig.sig != uci->cpu_sig.sig) || (nsig.pf != uci->cpu_sig.pf)) { __microcode_fini_cpu(cpu); printk(KERN_ERR "cached ucode doesn't match the resuming cpu #%d\n", cpu); /* Should we look for a new ucode here? */ return 1; } return 0; } static long microcode_update_cpu(void *unused) { struct ucode_cpu_info *uci = ucode_cpu_info + smp_processor_id(); int err = 0; /* * Check if the system resume is in progress (uci->valid != NULL), * otherwise just request a firmware: */ if (uci->valid) { err = microcode_resume_cpu(smp_processor_id()); } else { collect_cpu_info(smp_processor_id()); if (uci->valid && system_state == SYSTEM_RUNNING) err = microcode_ops->request_microcode_fw( smp_processor_id(), µcode_pdev->dev); } if (!err) microcode_ops->apply_microcode(smp_processor_id()); return err; } static int microcode_init_cpu(int cpu) { int err; mutex_lock(µcode_mutex); err = work_on_cpu(cpu, microcode_update_cpu, NULL); mutex_unlock(µcode_mutex); return err; } static int mc_sysdev_add(struct sys_device *sys_dev) { int err, cpu = sys_dev->id; struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (!cpu_online(cpu)) return 0; pr_debug("microcode: CPU%d added\n", cpu); memset(uci, 0, sizeof(*uci)); err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group); if (err) return err; err = microcode_init_cpu(cpu); if (err) sysfs_remove_group(&sys_dev->kobj, &mc_attr_group); return err; } static int mc_sysdev_remove(struct sys_device *sys_dev) { int cpu = sys_dev->id; if (!cpu_online(cpu)) return 0; pr_debug("microcode: CPU%d removed\n", cpu); microcode_fini_cpu(cpu); sysfs_remove_group(&sys_dev->kobj, &mc_attr_group); return 0; } static int mc_sysdev_resume(struct sys_device *dev) { int cpu = dev->id; if (!cpu_online(cpu)) return 0; /* only CPU 0 will apply ucode here */ microcode_update_cpu(NULL); return 0; } static struct sysdev_driver mc_sysdev_driver = { .add = mc_sysdev_add, .remove = mc_sysdev_remove, .resume = mc_sysdev_resume, }; static __cpuinit int mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; struct sys_device *sys_dev; sys_dev = get_cpu_sysdev(cpu); switch (action) { case CPU_ONLINE: case CPU_ONLINE_FROZEN: if (microcode_init_cpu(cpu)) printk(KERN_ERR "microcode: failed to init CPU%d\n", cpu); case CPU_DOWN_FAILED: case CPU_DOWN_FAILED_FROZEN: pr_debug("microcode: CPU%d added\n", cpu); if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group)) printk(KERN_ERR "microcode: Failed to create the sysfs " "group for CPU%d\n", cpu); break; case CPU_DOWN_PREPARE: case CPU_DOWN_PREPARE_FROZEN: /* Suspend is in progress, only remove the interface */ sysfs_remove_group(&sys_dev->kobj, &mc_attr_group); pr_debug("microcode: CPU%d removed\n", cpu); break; case CPU_DEAD: case CPU_UP_CANCELED_FROZEN: /* The CPU refused to come up during a system resume */ microcode_fini_cpu(cpu); break; } return NOTIFY_OK; } static struct notifier_block __refdata mc_cpu_notifier = { .notifier_call = mc_cpu_callback, }; static int __init microcode_init(void) { struct cpuinfo_x86 *c = &cpu_data(0); int error; if (c->x86_vendor == X86_VENDOR_INTEL) microcode_ops = init_intel_microcode(); else if (c->x86_vendor == X86_VENDOR_AMD) microcode_ops = init_amd_microcode(); if (!microcode_ops) { printk(KERN_ERR "microcode: no support for this CPU vendor\n"); return -ENODEV; } error = microcode_dev_init(); if (error) return error; microcode_pdev = platform_device_register_simple("microcode", -1, NULL, 0); if (IS_ERR(microcode_pdev)) { microcode_dev_exit(); return PTR_ERR(microcode_pdev); } get_online_cpus(); error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver); put_online_cpus(); if (error) { microcode_dev_exit(); platform_device_unregister(microcode_pdev); return error; } register_hotcpu_notifier(&mc_cpu_notifier); printk(KERN_INFO "Microcode Update Driver: v" MICROCODE_VERSION " ," " Peter Oruba\n"); return 0; } static void __exit microcode_exit(void) { microcode_dev_exit(); unregister_hotcpu_notifier(&mc_cpu_notifier); get_online_cpus(); sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver); put_online_cpus(); platform_device_unregister(microcode_pdev); microcode_ops = NULL; printk(KERN_INFO "Microcode Update Driver: v" MICROCODE_VERSION " removed.\n"); } module_init(microcode_init); module_exit(microcode_exit);