/*
* 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);
/* see notes above for revision 1.07. Apparent chip bug */
serialize_cpu();
/* 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(µcode_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);
/* see notes above for revision 1.07. Apparent chip bug */
serialize_cpu();
/* 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(µcode_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(µcode_sem);
user_buffer = (void __user *) buf;
user_buffer_size = (int) len;
ret = do_microcode_update();
if (!ret)
ret = (ssize_t)len;
up(µcode_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 = µcode_fops,
};
static int __init microcode_init (void)
{
int error;
error = misc_register(µcode_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(µcode_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);
