/* * Intel CPU Microcode Update Driver for Linux * * Copyright (C) 2000-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk> * 2006 Shaohua Li <shaohua.li@intel.com> * * 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 <tigran@sco.com> * Initial release. * 1.01 18 Feb 2000, Tigran Aivazian <tigran@sco.com> * Added read() support + cleanups. * 1.02 21 Feb 2000, Tigran Aivazian <tigran@sco.com> * Added 'device trimming' support. open(O_WRONLY) zeroes * and frees the saved copy of applied microcode. * 1.03 29 Feb 2000, Tigran Aivazian <tigran@sco.com> * Made to use devfs (/dev/cpu/microcode) + cleanups. * 1.04 06 Jun 2000, Simon Trimmer <simon@veritas.com> * Added misc device support (now uses both devfs and misc). * Added MICROCODE_IOCFREE ioctl to clear memory. * 1.05 09 Jun 2000, Simon Trimmer <simon@veritas.com> * Messages for error cases (non Intel & no suitable microcode). * 1.06 03 Aug 2000, Tigran Aivazian <tigran@veritas.com> * 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 <tigran@veritas.com> * 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 <ebiederman@lnxi.com> for the fix. * 1.08 11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and * Tigran Aivazian <tigran@veritas.com> * Intel Pentium 4 processor support and bugfixes. * 1.09 30 Oct 2001, Tigran Aivazian <tigran@veritas.com> * 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 <asit.k.mallick@intel.com> and * Tigran Aivazian <tigran@veritas.com>, * Serialize updates as required on HT processors due to * speculative nature of implementation. * 1.11 22 Mar 2002 Tigran Aivazian <tigran@veritas.com> * Fix the panic when writing zero-length microcode chunk. * 1.12 29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>, * Jun Nakajima <jun.nakajima@intel.com> * Support for the microcode updates in the new format. * 1.13 10 Oct 2003 Tigran Aivazian <tigran@veritas.com> * 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 <tigran@veritas.com> * Fix sigmatch() macro to handle old CPUs with pf == 0. * Thanks to Stuart Swales for pointing out this bug. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/platform_device.h> #include <linux/miscdevice.h> #include <linux/capability.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/cpu.h> #include <linux/fs.h> #include <linux/mm.h> #include <asm/microcode.h> #include <asm/processor.h> MODULE_DESCRIPTION("Microcode Update Driver"); MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>"); MODULE_LICENSE("GPL"); #define MICROCODE_VERSION "2.00" static struct microcode_ops *microcode_ops; /* * Synchronization. * * All non cpu-hotplug-callback call sites use: * * - microcode_mutex to synchronize with each other; * - get/put_online_cpus() to synchronize with * the cpu-hotplug-callback call sites. * * We guarantee that only a single cpu is being * updated at any particular moment of time. */ static DEFINE_MUTEX(microcode_mutex); struct ucode_cpu_info ucode_cpu_info[NR_CPUS]; EXPORT_SYMBOL_GPL(ucode_cpu_info); /* * Operations that are run on a target cpu: */ struct cpu_info_ctx { struct cpu_signature *cpu_sig; int err; }; static void collect_cpu_info_local(void *arg) { struct cpu_info_ctx *ctx = arg; ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(), ctx->cpu_sig); } static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig) { struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 }; int ret; ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1); if (!ret) ret = ctx.err; return ret; } static int collect_cpu_info(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; int ret; memset(uci, 0, sizeof(*uci)); ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig); if (!ret) uci->valid = 1; return ret; } struct apply_microcode_ctx { int err; }; static void apply_microcode_local(void *arg) { struct apply_microcode_ctx *ctx = arg; ctx->err = microcode_ops->apply_microcode(smp_processor_id()); } static int apply_microcode_on_target(int cpu) { struct apply_microcode_ctx ctx = { .err = 0 }; int ret; ret = smp_call_function_single(cpu, apply_microcode_local, &ctx, 1); if (!ret) ret = ctx.err; return ret; } #ifdef CONFIG_MICROCODE_OLD_INTERFACE static int do_microcode_update(const void __user *buf, size_t size) { int error = 0; int cpu; for_each_online_cpu(cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; enum ucode_state ustate; if (!uci->valid) continue; ustate = microcode_ops->request_microcode_user(cpu, buf, size); if (ustate == UCODE_ERROR) { error = -1; break; } else if (ustate == UCODE_OK) apply_microcode_on_target(cpu); } return error; } static int microcode_open(struct inode *unused1, struct file *unused2) { 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 = -EINVAL; if ((len >> PAGE_SHIFT) > totalram_pages) { pr_err("too much data (max %ld pages)\n", totalram_pages); return ret; } get_online_cpus(); mutex_lock(µcode_mutex); if (do_microcode_update(buf, len) == 0) 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", .nodename = "cpu/microcode", .fops = µcode_fops, }; static int __init microcode_dev_init(void) { int error; error = misc_register(µcode_dev); if (error) { pr_err("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 int reload_for_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; int err = 0; mutex_lock(µcode_mutex); if (uci->valid) { enum ucode_state ustate; ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev); if (ustate == UCODE_OK) apply_microcode_on_target(cpu); else if (ustate == UCODE_ERROR) err = -EINVAL; } mutex_unlock(µcode_mutex); return err; } static ssize_t reload_store(struct sys_device *dev, struct sysdev_attribute *attr, const char *buf, size_t size) { unsigned long val; int cpu = dev->id; int ret = 0; char *end; val = simple_strtoul(buf, &end, 0); if (end == buf) return -EINVAL; if (val == 1) { get_online_cpus(); if (cpu_online(cpu)) ret = reload_for_cpu(cpu); put_online_cpus(); } if (!ret) ret = size; return ret; } 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 enum ucode_state microcode_resume_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (!uci->mc) return UCODE_NFOUND; pr_debug("CPU%d updated upon resume\n", cpu); apply_microcode_on_target(cpu); return UCODE_OK; } static enum ucode_state microcode_init_cpu(int cpu) { enum ucode_state ustate; if (collect_cpu_info(cpu)) return UCODE_ERROR; /* --dimm. Trigger a delayed update? */ if (system_state != SYSTEM_RUNNING) return UCODE_NFOUND; ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev); if (ustate == UCODE_OK) { pr_debug("CPU%d updated upon init\n", cpu); apply_microcode_on_target(cpu); } return ustate; } static enum ucode_state microcode_update_cpu(int cpu) { struct ucode_cpu_info *uci = ucode_cpu_info + cpu; enum ucode_state ustate; if (uci->valid) ustate = microcode_resume_cpu(cpu); else ustate = microcode_init_cpu(cpu); return ustate; } static int mc_sysdev_add(struct sys_device *sys_dev) { int err, cpu = sys_dev->id; if (!cpu_online(cpu)) return 0; pr_debug("CPU%d added\n", cpu); err = sysfs_create_group(&sys_dev->kobj, &mc_attr_group); if (err) return err; if (microcode_init_cpu(cpu) == UCODE_ERROR) err = -EINVAL; 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("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; struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (!cpu_online(cpu)) return 0; /* * All non-bootup cpus are still disabled, * so only CPU 0 will apply ucode here. * * Moreover, there can be no concurrent * updates from any other places at this point. */ WARN_ON(cpu != 0); if (uci->valid && uci->mc) microcode_ops->apply_microcode(cpu); 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: microcode_update_cpu(cpu); case CPU_DOWN_FAILED: case CPU_DOWN_FAILED_FROZEN: pr_debug("CPU%d added\n", cpu); if (sysfs_create_group(&sys_dev->kobj, &mc_attr_group)) pr_err("Failed to create 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("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) { pr_err("no support for this CPU vendor\n"); return -ENODEV; } microcode_pdev = platform_device_register_simple("microcode", -1, NULL, 0); if (IS_ERR(microcode_pdev)) { microcode_dev_exit(); return PTR_ERR(microcode_pdev); } if (microcode_ops->init) microcode_ops->init(µcode_pdev->dev); get_online_cpus(); mutex_lock(µcode_mutex); error = sysdev_driver_register(&cpu_sysdev_class, &mc_sysdev_driver); mutex_unlock(µcode_mutex); put_online_cpus(); if (error) { platform_device_unregister(microcode_pdev); return error; } error = microcode_dev_init(); if (error) return error; register_hotcpu_notifier(&mc_cpu_notifier); pr_info("Microcode Update Driver: v" MICROCODE_VERSION " <tigran@aivazian.fsnet.co.uk>, Peter Oruba\n"); return 0; } module_init(microcode_init); static void __exit microcode_exit(void) { microcode_dev_exit(); unregister_hotcpu_notifier(&mc_cpu_notifier); get_online_cpus(); mutex_lock(µcode_mutex); sysdev_driver_unregister(&cpu_sysdev_class, &mc_sysdev_driver); mutex_unlock(µcode_mutex); put_online_cpus(); platform_device_unregister(microcode_pdev); if (microcode_ops->fini) microcode_ops->fini(); microcode_ops = NULL; pr_info("Microcode Update Driver: v" MICROCODE_VERSION " removed.\n"); } module_exit(microcode_exit);