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Diffstat (limited to 'arch/i386/kernel/microcode.c')
-rw-r--r--arch/i386/kernel/microcode.c512
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diff --git a/arch/i386/kernel/microcode.c b/arch/i386/kernel/microcode.c
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+++ b/arch/i386/kernel/microcode.c
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+/*
+ * Intel CPU Microcode Update Driver for Linux
+ *
+ * Copyright (C) 2000-2004 Tigran Aivazian
+ *
+ * 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 8.10 of Volume III, Intel Pentium 4 Manual,
+ * Order Number 245472 or free download from:
+ *
+ * http://developer.intel.com/design/pentium4/manuals/245472.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 DEBUG /* pr_debug */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/vmalloc.h>
+#include <linux/miscdevice.h>
+#include <linux/spinlock.h>
+#include <linux/mm.h>
+
+#include <asm/msr.h>
+#include <asm/uaccess.h>
+#include <asm/processor.h>
+
+MODULE_DESCRIPTION("Intel CPU (IA-32) Microcode Update Driver");
+MODULE_AUTHOR("Tigran Aivazian <tigran@veritas.com>");
+MODULE_LICENSE("GPL");
+
+#define MICROCODE_VERSION "1.14"
+
+#define DEFAULT_UCODE_DATASIZE (2000) /* 2000 bytes */
+#define MC_HEADER_SIZE (sizeof (microcode_header_t)) /* 48 bytes */
+#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE) /* 2048 bytes */
+#define EXT_HEADER_SIZE (sizeof (struct extended_sigtable)) /* 20 bytes */
+#define EXT_SIGNATURE_SIZE (sizeof (struct extended_signature)) /* 12 bytes */
+#define DWSIZE (sizeof (u32))
+#define get_totalsize(mc) \
+ (((microcode_t *)mc)->hdr.totalsize ? \
+ ((microcode_t *)mc)->hdr.totalsize : DEFAULT_UCODE_TOTALSIZE)
+#define get_datasize(mc) \
+ (((microcode_t *)mc)->hdr.datasize ? \
+ ((microcode_t *)mc)->hdr.datasize : DEFAULT_UCODE_DATASIZE)
+
+#define sigmatch(s1, s2, p1, p2) \
+ (((s1) == (s2)) && (((p1) & (p2)) || (((p1) == 0) && ((p2) == 0))))
+
+#define exttable_size(et) ((et)->count * EXT_SIGNATURE_SIZE + EXT_HEADER_SIZE)
+
+/* serialize access to the physical write to MSR 0x79 */
+static DEFINE_SPINLOCK(microcode_update_lock);
+
+/* no concurrent ->write()s are allowed on /dev/cpu/microcode */
+static DECLARE_MUTEX(microcode_sem);
+
+static void __user *user_buffer; /* user area microcode data buffer */
+static unsigned int user_buffer_size; /* it's size */
+
+typedef enum mc_error_code {
+ MC_SUCCESS = 0,
+ MC_NOTFOUND = 1,
+ MC_MARKED = 2,
+ MC_ALLOCATED = 3,
+} mc_error_code_t;
+
+static struct ucode_cpu_info {
+ unsigned int sig;
+ unsigned int pf;
+ unsigned int rev;
+ unsigned int cksum;
+ mc_error_code_t err;
+ microcode_t *mc;
+} ucode_cpu_info[NR_CPUS];
+
+static int microcode_open (struct inode *unused1, struct file *unused2)
+{
+ return capable(CAP_SYS_RAWIO) ? 0 : -EPERM;
+}
+
+static void collect_cpu_info (void *unused)
+{
+ int cpu_num = smp_processor_id();
+ struct cpuinfo_x86 *c = cpu_data + cpu_num;
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+ unsigned int val[2];
+
+ uci->sig = uci->pf = uci->rev = uci->cksum = 0;
+ uci->err = MC_NOTFOUND;
+ uci->mc = NULL;
+
+ if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
+ cpu_has(c, X86_FEATURE_IA64)) {
+ printk(KERN_ERR "microcode: CPU%d not a capable Intel processor\n", cpu_num);
+ return;
+ } else {
+ uci->sig = cpuid_eax(0x00000001);
+
+ if ((c->x86_model >= 5) || (c->x86 > 6)) {
+ /* get processor flags from MSR 0x17 */
+ rdmsr(MSR_IA32_PLATFORM_ID, val[0], val[1]);
+ uci->pf = 1 << ((val[1] >> 18) & 7);
+ }
+ }
+
+ wrmsr(MSR_IA32_UCODE_REV, 0, 0);
+ __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
+ /* get the current revision from MSR 0x8B */
+ rdmsr(MSR_IA32_UCODE_REV, val[0], uci->rev);
+ pr_debug("microcode: collect_cpu_info : sig=0x%x, pf=0x%x, rev=0x%x\n",
+ uci->sig, uci->pf, uci->rev);
+}
+
+static inline void mark_microcode_update (int cpu_num, microcode_header_t *mc_header, int sig, int pf, int cksum)
+{
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+
+ pr_debug("Microcode Found.\n");
+ pr_debug(" Header Revision 0x%x\n", mc_header->hdrver);
+ pr_debug(" Loader Revision 0x%x\n", mc_header->ldrver);
+ pr_debug(" Revision 0x%x \n", mc_header->rev);
+ pr_debug(" Date %x/%x/%x\n",
+ ((mc_header->date >> 24 ) & 0xff),
+ ((mc_header->date >> 16 ) & 0xff),
+ (mc_header->date & 0xFFFF));
+ pr_debug(" Signature 0x%x\n", sig);
+ pr_debug(" Type 0x%x Family 0x%x Model 0x%x Stepping 0x%x\n",
+ ((sig >> 12) & 0x3),
+ ((sig >> 8) & 0xf),
+ ((sig >> 4) & 0xf),
+ ((sig & 0xf)));
+ pr_debug(" Processor Flags 0x%x\n", pf);
+ pr_debug(" Checksum 0x%x\n", cksum);
+
+ if (mc_header->rev < uci->rev) {
+ printk(KERN_ERR "microcode: CPU%d not 'upgrading' to earlier revision"
+ " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
+ goto out;
+ } else if (mc_header->rev == uci->rev) {
+ /* notify the caller of success on this cpu */
+ uci->err = MC_SUCCESS;
+ printk(KERN_ERR "microcode: CPU%d already at revision"
+ " 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
+ goto out;
+ }
+
+ pr_debug("microcode: CPU%d found a matching microcode update with "
+ " revision 0x%x (current=0x%x)\n", cpu_num, mc_header->rev, uci->rev);
+ uci->cksum = cksum;
+ uci->pf = pf; /* keep the original mc pf for cksum calculation */
+ uci->err = MC_MARKED; /* found the match */
+out:
+ return;
+}
+
+static int find_matching_ucodes (void)
+{
+ int cursor = 0;
+ int error = 0;
+
+ while (cursor + MC_HEADER_SIZE < user_buffer_size) {
+ microcode_header_t mc_header;
+ void *newmc = NULL;
+ int i, sum, cpu_num, allocated_flag, total_size, data_size, ext_table_size;
+
+ if (copy_from_user(&mc_header, user_buffer + cursor, MC_HEADER_SIZE)) {
+ printk(KERN_ERR "microcode: error! Can not read user data\n");
+ error = -EFAULT;
+ goto out;
+ }
+
+ total_size = get_totalsize(&mc_header);
+ if ((cursor + total_size > user_buffer_size) || (total_size < DEFAULT_UCODE_TOTALSIZE)) {
+ printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
+ error = -EINVAL;
+ goto out;
+ }
+
+ data_size = get_datasize(&mc_header);
+ if ((data_size + MC_HEADER_SIZE > total_size) || (data_size < DEFAULT_UCODE_DATASIZE)) {
+ printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
+ error = -EINVAL;
+ goto out;
+ }
+
+ if (mc_header.ldrver != 1 || mc_header.hdrver != 1) {
+ printk(KERN_ERR "microcode: error! Unknown microcode update format\n");
+ error = -EINVAL;
+ goto out;
+ }
+
+ for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+ if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
+ continue;
+
+ if (sigmatch(mc_header.sig, uci->sig, mc_header.pf, uci->pf))
+ mark_microcode_update(cpu_num, &mc_header, mc_header.sig, mc_header.pf, mc_header.cksum);
+ }
+
+ ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
+ if (ext_table_size) {
+ struct extended_sigtable ext_header;
+ struct extended_signature ext_sig;
+ int ext_sigcount;
+
+ if ((ext_table_size < EXT_HEADER_SIZE)
+ || ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
+ printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
+ error = -EINVAL;
+ goto out;
+ }
+ if (copy_from_user(&ext_header, user_buffer + cursor
+ + MC_HEADER_SIZE + data_size, EXT_HEADER_SIZE)) {
+ printk(KERN_ERR "microcode: error! Can not read user data\n");
+ error = -EFAULT;
+ goto out;
+ }
+ if (ext_table_size != exttable_size(&ext_header)) {
+ printk(KERN_ERR "microcode: error! Bad data in microcode data file\n");
+ error = -EFAULT;
+ goto out;
+ }
+
+ ext_sigcount = ext_header.count;
+
+ for (i = 0; i < ext_sigcount; i++) {
+ if (copy_from_user(&ext_sig, user_buffer + cursor + MC_HEADER_SIZE + data_size + EXT_HEADER_SIZE
+ + EXT_SIGNATURE_SIZE * i, EXT_SIGNATURE_SIZE)) {
+ printk(KERN_ERR "microcode: error! Can not read user data\n");
+ error = -EFAULT;
+ goto out;
+ }
+ for (cpu_num = 0; cpu_num < num_online_cpus(); cpu_num++) {
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+ if (uci->err != MC_NOTFOUND) /* already found a match or not an online cpu*/
+ continue;
+ if (sigmatch(ext_sig.sig, uci->sig, ext_sig.pf, uci->pf)) {
+ mark_microcode_update(cpu_num, &mc_header, ext_sig.sig, ext_sig.pf, ext_sig.cksum);
+ }
+ }
+ }
+ }
+ /* now check if any cpu has matched */
+ for (cpu_num = 0, allocated_flag = 0, sum = 0; cpu_num < num_online_cpus(); cpu_num++) {
+ if (ucode_cpu_info[cpu_num].err == MC_MARKED) {
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+ if (!allocated_flag) {
+ allocated_flag = 1;
+ newmc = vmalloc(total_size);
+ if (!newmc) {
+ printk(KERN_ERR "microcode: error! Can not allocate memory\n");
+ error = -ENOMEM;
+ goto out;
+ }
+ if (copy_from_user(newmc + MC_HEADER_SIZE,
+ user_buffer + cursor + MC_HEADER_SIZE,
+ total_size - MC_HEADER_SIZE)) {
+ printk(KERN_ERR "microcode: error! Can not read user data\n");
+ vfree(newmc);
+ error = -EFAULT;
+ goto out;
+ }
+ memcpy(newmc, &mc_header, MC_HEADER_SIZE);
+ /* check extended table checksum */
+ if (ext_table_size) {
+ int ext_table_sum = 0;
+ int * ext_tablep = (((void *) newmc) + MC_HEADER_SIZE + data_size);
+ i = ext_table_size / DWSIZE;
+ while (i--) ext_table_sum += ext_tablep[i];
+ if (ext_table_sum) {
+ printk(KERN_WARNING "microcode: aborting, bad extended signature table checksum\n");
+ vfree(newmc);
+ error = -EINVAL;
+ goto out;
+ }
+ }
+
+ /* calculate the checksum */
+ i = (MC_HEADER_SIZE + data_size) / DWSIZE;
+ while (i--) sum += ((int *)newmc)[i];
+ sum -= (mc_header.sig + mc_header.pf + mc_header.cksum);
+ }
+ ucode_cpu_info[cpu_num].mc = newmc;
+ ucode_cpu_info[cpu_num].err = MC_ALLOCATED; /* mc updated */
+ if (sum + uci->sig + uci->pf + uci->cksum != 0) {
+ printk(KERN_ERR "microcode: CPU%d aborting, bad checksum\n", cpu_num);
+ error = -EINVAL;
+ goto out;
+ }
+ }
+ }
+ cursor += total_size; /* goto the next update patch */
+ } /* end of while */
+out:
+ return error;
+}
+
+static void do_update_one (void * unused)
+{
+ unsigned long flags;
+ unsigned int val[2];
+ int cpu_num = smp_processor_id();
+ struct ucode_cpu_info *uci = ucode_cpu_info + cpu_num;
+
+ if (uci->mc == NULL) {
+ printk(KERN_INFO "microcode: No new microcode data for CPU%d\n", cpu_num);
+ return;
+ }
+
+ /* serialize access to the physical write to MSR 0x79 */
+ spin_lock_irqsave(&microcode_update_lock, flags);
+
+ /* write microcode via MSR 0x79 */
+ wrmsr(MSR_IA32_UCODE_WRITE,
+ (unsigned long) uci->mc->bits,
+ (unsigned long) uci->mc->bits >> 16 >> 16);
+ wrmsr(MSR_IA32_UCODE_REV, 0, 0);
+
+ __asm__ __volatile__ ("cpuid" : : : "ax", "bx", "cx", "dx");
+ /* get the current revision from MSR 0x8B */
+ rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
+
+ /* notify the caller of success on this cpu */
+ uci->err = MC_SUCCESS;
+ spin_unlock_irqrestore(&microcode_update_lock, flags);
+ printk(KERN_INFO "microcode: CPU%d updated from revision "
+ "0x%x to 0x%x, date = %08x \n",
+ cpu_num, uci->rev, val[1], uci->mc->hdr.date);
+ return;
+}
+
+static int do_microcode_update (void)
+{
+ int i, error;
+
+ if (on_each_cpu(collect_cpu_info, NULL, 1, 1) != 0) {
+ printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
+ error = -EIO;
+ goto out;
+ }
+
+ if ((error = find_matching_ucodes())) {
+ printk(KERN_ERR "microcode: Error in the microcode data\n");
+ goto out_free;
+ }
+
+ if (on_each_cpu(do_update_one, NULL, 1, 1) != 0) {
+ printk(KERN_ERR "microcode: Error! Could not run on all processors\n");
+ error = -EIO;
+ }
+
+out_free:
+ for (i = 0; i < num_online_cpus(); i++) {
+ if (ucode_cpu_info[i].mc) {
+ int j;
+ void *tmp = ucode_cpu_info[i].mc;
+ vfree(tmp);
+ for (j = i; j < num_online_cpus(); j++) {
+ if (ucode_cpu_info[j].mc == tmp)
+ ucode_cpu_info[j].mc = NULL;
+ }
+ }
+ }
+out:
+ return error;
+}
+
+static ssize_t microcode_write (struct file *file, const char __user *buf, size_t len, loff_t *ppos)
+{
+ ssize_t ret;
+
+ if (len < DEFAULT_UCODE_TOTALSIZE) {
+ printk(KERN_ERR "microcode: not enough data\n");
+ return -EINVAL;
+ }
+
+ if ((len >> PAGE_SHIFT) > num_physpages) {
+ printk(KERN_ERR "microcode: too much data (max %ld pages)\n", num_physpages);
+ return -EINVAL;
+ }
+
+ down(&microcode_sem);
+
+ user_buffer = (void __user *) buf;
+ user_buffer_size = (int) len;
+
+ ret = do_microcode_update();
+ if (!ret)
+ ret = (ssize_t)len;
+
+ up(&microcode_sem);
+
+ return ret;
+}
+
+static int microcode_ioctl (struct inode *inode, struct file *file,
+ unsigned int cmd, unsigned long arg)
+{
+ switch (cmd) {
+ /*
+ * XXX: will be removed after microcode_ctl
+ * is updated to ignore failure of this ioctl()
+ */
+ case MICROCODE_IOCFREE:
+ return 0;
+ default:
+ return -EINVAL;
+ }
+ return -EINVAL;
+}
+
+static struct file_operations microcode_fops = {
+ .owner = THIS_MODULE,
+ .write = microcode_write,
+ .ioctl = microcode_ioctl,
+ .open = microcode_open,
+};
+
+static struct miscdevice microcode_dev = {
+ .minor = MICROCODE_MINOR,
+ .name = "microcode",
+ .devfs_name = "cpu/microcode",
+ .fops = &microcode_fops,
+};
+
+static int __init microcode_init (void)
+{
+ int error;
+
+ error = misc_register(&microcode_dev);
+ if (error) {
+ printk(KERN_ERR
+ "microcode: can't misc_register on minor=%d\n",
+ MICROCODE_MINOR);
+ return error;
+ }
+
+ printk(KERN_INFO
+ "IA-32 Microcode Update Driver: v" MICROCODE_VERSION " <tigran@veritas.com>\n");
+ return 0;
+}
+
+static void __exit microcode_exit (void)
+{
+ misc_deregister(&microcode_dev);
+ printk(KERN_INFO "IA-32 Microcode Update Driver v" MICROCODE_VERSION " unregistered\n");
+}
+
+module_init(microcode_init)
+module_exit(microcode_exit)
+MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-25 04:33:18 +0000