/* * 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/Assets/PDF/manual/253668.pdf * * 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. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #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; bool dis_ucode_ldr; module_param(dis_ucode_ldr, bool, 0); /* * 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 *inode, struct file *file) { return capable(CAP_SYS_RAWIO) ? nonseekable_open(inode, file) : -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; if (ret > 0) perf_check_microcode(); 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, .llseek = no_llseek, }; 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 __exit microcode_dev_exit(void) { misc_deregister(µcode_dev); } MODULE_ALIAS_MISCDEV(MICROCODE_MINOR); MODULE_ALIAS("devname:cpu/microcode"); #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; enum ucode_state ustate; int err = 0; if (!uci->valid) return err; ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev, true); if (ustate == UCODE_OK) apply_microcode_on_target(cpu); else if (ustate == UCODE_ERROR) err = -EINVAL; return err; } static ssize_t reload_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { unsigned long val; int cpu; ssize_t ret = 0, tmp_ret; ret = kstrtoul(buf, 0, &val); if (ret) return ret; if (val != 1) return size; get_online_cpus(); mutex_lock(µcode_mutex); for_each_online_cpu(cpu) { tmp_ret = reload_for_cpu(cpu); if (tmp_ret != 0) pr_warn("Error reloading microcode on CPU %d\n", cpu); /* save retval of the first encountered reload error */ if (!ret) ret = tmp_ret; } if (!ret) perf_check_microcode(); mutex_unlock(µcode_mutex); put_online_cpus(); if (!ret) ret = size; return ret; } static ssize_t version_show(struct device *dev, struct device_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 device *dev, struct device_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 DEVICE_ATTR(reload, 0200, NULL, reload_store); static DEVICE_ATTR(version, 0400, version_show, NULL); static DEVICE_ATTR(processor_flags, 0400, pf_show, NULL); static struct attribute *mc_default_attrs[] = { &dev_attr_version.attr, &dev_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) { microcode_ops->microcode_fini_cpu(cpu); } static enum ucode_state microcode_resume_cpu(int cpu) { pr_debug("CPU%d updated upon resume\n", cpu); if (apply_microcode_on_target(cpu)) return UCODE_ERROR; return UCODE_OK; } static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw) { enum ucode_state ustate; struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (uci && uci->valid) return UCODE_OK; 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, refresh_fw); 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; if (uci->valid) return microcode_resume_cpu(cpu); return microcode_init_cpu(cpu, false); } static int mc_device_add(struct device *dev, struct subsys_interface *sif) { int err, cpu = dev->id; if (!cpu_online(cpu)) return 0; pr_debug("CPU%d added\n", cpu); err = sysfs_create_group(&dev->kobj, &mc_attr_group); if (err) return err; if (microcode_init_cpu(cpu, true) == UCODE_ERROR) return -EINVAL; return err; } static int mc_device_remove(struct device *dev, struct subsys_interface *sif) { int cpu = dev->id; if (!cpu_online(cpu)) return 0; pr_debug("CPU%d removed\n", cpu); microcode_fini_cpu(cpu); sysfs_remove_group(&dev->kobj, &mc_attr_group); return 0; } static struct subsys_interface mc_cpu_interface = { .name = "microcode", .subsys = &cpu_subsys, .add_dev = mc_device_add, .remove_dev = mc_device_remove, }; /** * mc_bp_resume - Update boot CPU microcode during resume. */ static void mc_bp_resume(void) { int cpu = smp_processor_id(); struct ucode_cpu_info *uci = ucode_cpu_info + cpu; if (uci->valid && uci->mc) microcode_ops->apply_microcode(cpu); else if (!uci->mc) reload_early_microcode(); } static struct syscore_ops mc_syscore_ops = { .resume = mc_bp_resume, }; static int mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned long)hcpu; struct device *dev; dev = get_cpu_device(cpu); switch (action & ~CPU_TASKS_FROZEN) { case CPU_ONLINE: microcode_update_cpu(cpu); pr_debug("CPU%d added\n", cpu); /* * "break" is missing on purpose here because we want to fall * through in order to create the sysfs group. */ case CPU_DOWN_FAILED: if (sysfs_create_group(&dev->kobj, &mc_attr_group)) pr_err("Failed to create group for CPU%d\n", cpu); break; case CPU_DOWN_PREPARE: /* Suspend is in progress, only remove the interface */ sysfs_remove_group(&dev->kobj, &mc_attr_group); pr_debug("CPU%d removed\n", cpu); break; /* * case CPU_DEAD: * * When a CPU goes offline, don't free up or invalidate the copy of * the microcode in kernel memory, so that we can reuse it when the * CPU comes back online without unnecessarily requesting the userspace * for it again. */ } /* The CPU refused to come up during a system resume */ if (action == CPU_UP_CANCELED_FROZEN) microcode_fini_cpu(cpu); return NOTIFY_OK; } static struct notifier_block __refdata mc_cpu_notifier = { .notifier_call = mc_cpu_callback, }; #ifdef MODULE /* Autoload on Intel and AMD systems */ static const struct x86_cpu_id __initconst microcode_id[] = { #ifdef CONFIG_MICROCODE_INTEL { X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, }, #endif #ifdef CONFIG_MICROCODE_AMD { X86_VENDOR_AMD, X86_FAMILY_ANY, X86_MODEL_ANY, }, #endif {} }; MODULE_DEVICE_TABLE(x86cpu, microcode_id); #endif static struct attribute *cpu_root_microcode_attrs[] = { &dev_attr_reload.attr, NULL }; static struct attribute_group cpu_root_microcode_group = { .name = "microcode", .attrs = cpu_root_microcode_attrs, }; static int __init microcode_init(void) { struct cpuinfo_x86 *c = &cpu_data(0); int error; if (paravirt_enabled() || dis_ucode_ldr) return 0; 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(); else pr_err("no support for this CPU vendor\n"); if (!microcode_ops) return -ENODEV; microcode_pdev = platform_device_register_simple("microcode", -1, NULL, 0); if (IS_ERR(microcode_pdev)) return PTR_ERR(microcode_pdev); get_online_cpus(); mutex_lock(µcode_mutex); error = subsys_interface_register(&mc_cpu_interface); if (!error) perf_check_microcode(); mutex_unlock(µcode_mutex); put_online_cpus(); if (error) goto out_pdev; error = sysfs_create_group(&cpu_subsys.dev_root->kobj, &cpu_root_microcode_group); if (error) { pr_err("Error creating microcode group!\n"); goto out_driver; } error = microcode_dev_init(); if (error) goto out_ucode_group; register_syscore_ops(&mc_syscore_ops); register_hotcpu_notifier(&mc_cpu_notifier); pr_info("Microcode Update Driver: v" MICROCODE_VERSION " , Peter Oruba\n"); return 0; out_ucode_group: sysfs_remove_group(&cpu_subsys.dev_root->kobj, &cpu_root_microcode_group); out_driver: get_online_cpus(); mutex_lock(µcode_mutex); subsys_interface_unregister(&mc_cpu_interface); mutex_unlock(µcode_mutex); put_online_cpus(); out_pdev: platform_device_unregister(microcode_pdev); return error; } module_init(microcode_init); static void __exit microcode_exit(void) { struct cpuinfo_x86 *c = &cpu_data(0); microcode_dev_exit(); unregister_hotcpu_notifier(&mc_cpu_notifier); unregister_syscore_ops(&mc_syscore_ops); sysfs_remove_group(&cpu_subsys.dev_root->kobj, &cpu_root_microcode_group); get_online_cpus(); mutex_lock(µcode_mutex); subsys_interface_unregister(&mc_cpu_interface); mutex_unlock(µcode_mutex); put_online_cpus(); platform_device_unregister(microcode_pdev); microcode_ops = NULL; if (c->x86_vendor == X86_VENDOR_AMD) exit_amd_microcode(); pr_info("Microcode Update Driver: v" MICROCODE_VERSION " removed.\n"); } module_exit(microcode_exit);