linux/arch/x86/kernel/microcode_intel.c
Srivatsa S. Bhat 7164b3f5e5 x86/microcode: Ensure that module is only loaded on supported Intel CPUs
Exit early when there's no support for a particular CPU family.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Andreas Herrmann <andreas.herrmann3@amd.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Dave Jones <davej@redhat.com>
Cc: tigran@aivazian.fsnet.co.uk
Cc: Borislav Petkov <borislav.petkov@amd.com>
Link: http://lkml.kernel.org/r/4F8BDB58.6070007@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2012-05-07 14:37:14 +02:00

471 lines
13 KiB
C

/*
* 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/firmware.h>
#include <linux/uaccess.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <asm/microcode.h>
#include <asm/processor.h>
#include <asm/msr.h>
MODULE_DESCRIPTION("Microcode Update Driver");
MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
MODULE_LICENSE("GPL");
struct microcode_header_intel {
unsigned int hdrver;
unsigned int rev;
unsigned int date;
unsigned int sig;
unsigned int cksum;
unsigned int ldrver;
unsigned int pf;
unsigned int datasize;
unsigned int totalsize;
unsigned int reserved[3];
};
struct microcode_intel {
struct microcode_header_intel hdr;
unsigned int bits[0];
};
/* microcode format is extended from prescott processors */
struct extended_signature {
unsigned int sig;
unsigned int pf;
unsigned int cksum;
};
struct extended_sigtable {
unsigned int count;
unsigned int cksum;
unsigned int reserved[3];
struct extended_signature sigs[0];
};
#define DEFAULT_UCODE_DATASIZE (2000)
#define MC_HEADER_SIZE (sizeof(struct microcode_header_intel))
#define DEFAULT_UCODE_TOTALSIZE (DEFAULT_UCODE_DATASIZE + MC_HEADER_SIZE)
#define EXT_HEADER_SIZE (sizeof(struct extended_sigtable))
#define EXT_SIGNATURE_SIZE (sizeof(struct extended_signature))
#define DWSIZE (sizeof(u32))
#define get_totalsize(mc) \
(((struct microcode_intel *)mc)->hdr.totalsize ? \
((struct microcode_intel *)mc)->hdr.totalsize : \
DEFAULT_UCODE_TOTALSIZE)
#define get_datasize(mc) \
(((struct microcode_intel *)mc)->hdr.datasize ? \
((struct microcode_intel *)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)
static int collect_cpu_info(int cpu_num, struct cpu_signature *csig)
{
struct cpuinfo_x86 *c = &cpu_data(cpu_num);
unsigned int val[2];
memset(csig, 0, sizeof(*csig));
csig->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]);
csig->pf = 1 << ((val[1] >> 18) & 7);
}
csig->rev = c->microcode;
pr_info("CPU%d sig=0x%x, pf=0x%x, revision=0x%x\n",
cpu_num, csig->sig, csig->pf, csig->rev);
return 0;
}
static inline int update_match_cpu(struct cpu_signature *csig, int sig, int pf)
{
return (!sigmatch(sig, csig->sig, pf, csig->pf)) ? 0 : 1;
}
static inline int
update_match_revision(struct microcode_header_intel *mc_header, int rev)
{
return (mc_header->rev <= rev) ? 0 : 1;
}
static int microcode_sanity_check(void *mc)
{
unsigned long total_size, data_size, ext_table_size;
struct microcode_header_intel *mc_header = mc;
struct extended_sigtable *ext_header = NULL;
int sum, orig_sum, ext_sigcount = 0, i;
struct extended_signature *ext_sig;
total_size = get_totalsize(mc_header);
data_size = get_datasize(mc_header);
if (data_size + MC_HEADER_SIZE > total_size) {
pr_err("error! Bad data size in microcode data file\n");
return -EINVAL;
}
if (mc_header->ldrver != 1 || mc_header->hdrver != 1) {
pr_err("error! Unknown microcode update format\n");
return -EINVAL;
}
ext_table_size = total_size - (MC_HEADER_SIZE + data_size);
if (ext_table_size) {
if ((ext_table_size < EXT_HEADER_SIZE)
|| ((ext_table_size - EXT_HEADER_SIZE) % EXT_SIGNATURE_SIZE)) {
pr_err("error! Small exttable size in microcode data file\n");
return -EINVAL;
}
ext_header = mc + MC_HEADER_SIZE + data_size;
if (ext_table_size != exttable_size(ext_header)) {
pr_err("error! Bad exttable size in microcode data file\n");
return -EFAULT;
}
ext_sigcount = ext_header->count;
}
/* check extended table checksum */
if (ext_table_size) {
int ext_table_sum = 0;
int *ext_tablep = (int *)ext_header;
i = ext_table_size / DWSIZE;
while (i--)
ext_table_sum += ext_tablep[i];
if (ext_table_sum) {
pr_warning("aborting, bad extended signature table checksum\n");
return -EINVAL;
}
}
/* calculate the checksum */
orig_sum = 0;
i = (MC_HEADER_SIZE + data_size) / DWSIZE;
while (i--)
orig_sum += ((int *)mc)[i];
if (orig_sum) {
pr_err("aborting, bad checksum\n");
return -EINVAL;
}
if (!ext_table_size)
return 0;
/* check extended signature checksum */
for (i = 0; i < ext_sigcount; i++) {
ext_sig = (void *)ext_header + EXT_HEADER_SIZE +
EXT_SIGNATURE_SIZE * i;
sum = orig_sum
- (mc_header->sig + mc_header->pf + mc_header->cksum)
+ (ext_sig->sig + ext_sig->pf + ext_sig->cksum);
if (sum) {
pr_err("aborting, bad checksum\n");
return -EINVAL;
}
}
return 0;
}
/*
* return 0 - no update found
* return 1 - found update
*/
static int
get_matching_microcode(struct cpu_signature *cpu_sig, void *mc, int rev)
{
struct microcode_header_intel *mc_header = mc;
struct extended_sigtable *ext_header;
unsigned long total_size = get_totalsize(mc_header);
int ext_sigcount, i;
struct extended_signature *ext_sig;
if (!update_match_revision(mc_header, rev))
return 0;
if (update_match_cpu(cpu_sig, mc_header->sig, mc_header->pf))
return 1;
/* Look for ext. headers: */
if (total_size <= get_datasize(mc_header) + MC_HEADER_SIZE)
return 0;
ext_header = mc + get_datasize(mc_header) + MC_HEADER_SIZE;
ext_sigcount = ext_header->count;
ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
for (i = 0; i < ext_sigcount; i++) {
if (update_match_cpu(cpu_sig, ext_sig->sig, ext_sig->pf))
return 1;
ext_sig++;
}
return 0;
}
static int apply_microcode(int cpu)
{
struct microcode_intel *mc_intel;
struct ucode_cpu_info *uci;
unsigned int val[2];
int cpu_num = raw_smp_processor_id();
struct cpuinfo_x86 *c = &cpu_data(cpu_num);
uci = ucode_cpu_info + cpu;
mc_intel = uci->mc;
/* We should bind the task to the CPU */
BUG_ON(cpu_num != cpu);
if (mc_intel == NULL)
return 0;
/* write microcode via MSR 0x79 */
wrmsr(MSR_IA32_UCODE_WRITE,
(unsigned long) mc_intel->bits,
(unsigned long) mc_intel->bits >> 16 >> 16);
wrmsr(MSR_IA32_UCODE_REV, 0, 0);
/* As documented in the SDM: Do a CPUID 1 here */
sync_core();
/* get the current revision from MSR 0x8B */
rdmsr(MSR_IA32_UCODE_REV, val[0], val[1]);
if (val[1] != mc_intel->hdr.rev) {
pr_err("CPU%d update to revision 0x%x failed\n",
cpu_num, mc_intel->hdr.rev);
return -1;
}
pr_info("CPU%d updated to revision 0x%x, date = %04x-%02x-%02x\n",
cpu_num, val[1],
mc_intel->hdr.date & 0xffff,
mc_intel->hdr.date >> 24,
(mc_intel->hdr.date >> 16) & 0xff);
uci->cpu_sig.rev = val[1];
c->microcode = val[1];
return 0;
}
static enum ucode_state generic_load_microcode(int cpu, void *data, size_t size,
int (*get_ucode_data)(void *, const void *, size_t))
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
u8 *ucode_ptr = data, *new_mc = NULL, *mc = NULL;
int new_rev = uci->cpu_sig.rev;
unsigned int leftover = size;
enum ucode_state state = UCODE_OK;
unsigned int curr_mc_size = 0;
while (leftover) {
struct microcode_header_intel mc_header;
unsigned int mc_size;
if (get_ucode_data(&mc_header, ucode_ptr, sizeof(mc_header)))
break;
mc_size = get_totalsize(&mc_header);
if (!mc_size || mc_size > leftover) {
pr_err("error! Bad data in microcode data file\n");
break;
}
/* For performance reasons, reuse mc area when possible */
if (!mc || mc_size > curr_mc_size) {
vfree(mc);
mc = vmalloc(mc_size);
if (!mc)
break;
curr_mc_size = mc_size;
}
if (get_ucode_data(mc, ucode_ptr, mc_size) ||
microcode_sanity_check(mc) < 0) {
break;
}
if (get_matching_microcode(&uci->cpu_sig, mc, new_rev)) {
vfree(new_mc);
new_rev = mc_header.rev;
new_mc = mc;
mc = NULL; /* trigger new vmalloc */
}
ucode_ptr += mc_size;
leftover -= mc_size;
}
vfree(mc);
if (leftover) {
vfree(new_mc);
state = UCODE_ERROR;
goto out;
}
if (!new_mc) {
state = UCODE_NFOUND;
goto out;
}
vfree(uci->mc);
uci->mc = (struct microcode_intel *)new_mc;
pr_debug("CPU%d found a matching microcode update with version 0x%x (current=0x%x)\n",
cpu, new_rev, uci->cpu_sig.rev);
out:
return state;
}
static int get_ucode_fw(void *to, const void *from, size_t n)
{
memcpy(to, from, n);
return 0;
}
static enum ucode_state request_microcode_fw(int cpu, struct device *device)
{
char name[30];
struct cpuinfo_x86 *c = &cpu_data(cpu);
const struct firmware *firmware;
enum ucode_state ret;
sprintf(name, "intel-ucode/%02x-%02x-%02x",
c->x86, c->x86_model, c->x86_mask);
if (request_firmware(&firmware, name, device)) {
pr_debug("data file %s load failed\n", name);
return UCODE_NFOUND;
}
ret = generic_load_microcode(cpu, (void *)firmware->data,
firmware->size, &get_ucode_fw);
release_firmware(firmware);
return ret;
}
static int get_ucode_user(void *to, const void *from, size_t n)
{
return copy_from_user(to, from, n);
}
static enum ucode_state
request_microcode_user(int cpu, const void __user *buf, size_t size)
{
return generic_load_microcode(cpu, (void *)buf, size, &get_ucode_user);
}
static void microcode_fini_cpu(int cpu)
{
struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
vfree(uci->mc);
uci->mc = NULL;
}
static struct microcode_ops microcode_intel_ops = {
.request_microcode_user = request_microcode_user,
.request_microcode_fw = request_microcode_fw,
.collect_cpu_info = collect_cpu_info,
.apply_microcode = apply_microcode,
.microcode_fini_cpu = microcode_fini_cpu,
};
struct microcode_ops * __init init_intel_microcode(void)
{
struct cpuinfo_x86 *c = &cpu_data(0);
if (c->x86_vendor != X86_VENDOR_INTEL || c->x86 < 6 ||
cpu_has(c, X86_FEATURE_IA64)) {
pr_err("Intel CPU family 0x%x not supported\n", c->x86);
return NULL;
}
return &microcode_intel_ops;
}