1 files changed, 512 insertions, 0 deletions

diff --git a/arch/i386/kernel/microcode.c b/arch/i386/kernel/microcode.c
new file mode 100644
index 000000000000..a77c612aad00
--- /dev/null
+++ b/arch/i386/kernel/microcode.c
@@ -0,0 +1,512 @@
+/*
+ *      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);