| /* |
| * 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 <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 *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; |
| |
| 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 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; |
| 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) { |
| sysfs_remove_group(&sys_dev->kobj, &mc_attr_group); |
| return -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); |
| } |
| |
| 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); |
| |
| microcode_ops = NULL; |
| |
| pr_info("Microcode Update Driver: v" MICROCODE_VERSION " removed.\n"); |
| } |
| module_exit(microcode_exit); |