diff options
Diffstat (limited to 'arch/x86/kernel/cpu/microcode/core.c')
| -rw-r--r-- | arch/x86/kernel/cpu/microcode/core.c | 645 |
1 files changed, 645 insertions, 0 deletions
diff --git a/arch/x86/kernel/cpu/microcode/core.c b/arch/x86/kernel/cpu/microcode/core.c new file mode 100644 index 000000000000..15c987698b0f --- /dev/null +++ b/arch/x86/kernel/cpu/microcode/core.c @@ -0,0 +1,645 @@ +/* + * 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/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 <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 <linux/syscore_ops.h> + +#include <asm/microcode.h> +#include <asm/processor.h> +#include <asm/cpu_device_id.h> +#include <asm/perf_event.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 *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); +} + +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 (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 + " <tigran@aivazian.fsnet.co.uk>, 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); |