/*
* 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>
*
* Intel CPU microcode early update for Linux
*
* Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
* H Peter Anvin" <hpa@zytor.com>
*
* 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.
*/
/*
* This needs to be before all headers so that pr_debug in printk.h doesn't turn
* printk calls into no_printk().
*
*#define DEBUG
*/
#define pr_fmt(fmt) "microcode: " fmt
#include <linux/earlycpio.h>
#include <linux/firmware.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <linux/initrd.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/cpu.h>
#include <linux/mm.h>
#include <asm/microcode_intel.h>
#include <asm/processor.h>
#include <asm/tlbflush.h>
#include <asm/setup.h>
#include <asm/msr.h>
static const char ucode_path[] = "kernel/x86/microcode/GenuineIntel.bin";
/* Current microcode patch used in early patching */
struct microcode_intel *intel_ucode_patch;
static inline bool cpu_signatures_match(unsigned int s1, unsigned int p1,
unsigned int s2, unsigned int p2)
{
if (s1 != s2)
return false;
/* Processor flags are either both 0 ... */
if (!p1 && !p2)
return true;
/* ... or they intersect. */
return p1 & p2;
}
/*
* Returns 1 if update has been found, 0 otherwise.
*/
static int find_matching_signature(void *mc, unsigned int csig, int cpf)
{
struct microcode_header_intel *mc_hdr = mc;
struct extended_sigtable *ext_hdr;
struct extended_signature *ext_sig;
int i;
if (cpu_signatures_match(csig, cpf, mc_hdr->sig, mc_hdr->pf))
return 1;
/* Look for ext. headers: */
if (get_totalsize(mc_hdr) <= get_datasize(mc_hdr) + MC_HEADER_SIZE)
return 0;
ext_hdr = mc + get_datasize(mc_hdr) + MC_HEADER_SIZE;
ext_sig = (void *)ext_hdr + EXT_HEADER_SIZE;
for (i = 0; i < ext_hdr->count; i++) {
if (cpu_signatures_match(csig, cpf, ext_sig->sig, ext_sig->pf))
return 1;
ext_sig++;
}
return 0;
}
/*
* Returns 1 if update has been found, 0 otherwise.
*/
static int has_newer_microcode(void *mc, unsigned int csig, int cpf, int new_rev)
{
struct microcode_header_intel *mc_hdr = mc;
if (mc_hdr->rev <= new_rev)
return 0;
return find_matching_signature(mc, csig, cpf);
}
/*
* Given CPU signature and a microcode patch, this function finds if the
* microcode patch has matching family and model with the CPU.
*
* %true - if there's a match
* %false - otherwise
*/
static bool microcode_matches(struct microcode_header_intel *mc_header,
unsigned long sig)
{
unsigned long total_size = get_totalsize(mc_header);
unsigned long data_size = get_datasize(mc_header);
struct extended_sigtable *ext_header;
unsigned int fam_ucode, model_ucode;
struct extended_signature *ext_sig;
unsigned int fam, model;
int ext_sigcount, i;
fam = x86_family(sig);
model = x86_model(sig);
fam_ucode = x86_family(mc_header->sig);
model_ucode = x86_model(mc_header->sig);
if (fam == fam_ucode && model == model_ucode)
return true;
/* Look for ext. headers: */
if (total_size <= data_size + MC_HEADER_SIZE)
return false;
ext_header = (void *) mc_header + data_size + MC_HEADER_SIZE;
ext_sig = (void *)ext_header + EXT_HEADER_SIZE;
ext_sigcount = ext_header->count;
for (i = 0; i < ext_sigcount; i++) {
fam_ucode = x86_family(ext_sig->sig);
model_ucode = x86_model(ext_sig->sig);
if (fam == fam_ucode && model == model_ucode)
return true;
ext_sig++;
}
return false;
}
static struct ucode_patch *__alloc_microcode_buf(void *data, unsigned int size)
{
struct ucode_patch *p;
p = kzalloc(size, GFP_KERNEL);
if (!p)
return ERR_PTR(-ENOMEM);
p->data = kmemdup(data,