/*
* 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>
/*
* Temporary microcode blobs pointers storage. We note here during early load
* the pointers to microcode blobs we've got from whatever storage (detached
* initrd, builtin). Later on, we put those into final storage
* mc_saved_data.mc_saved.
*
* Important: those are offsets from the beginning of initrd or absolute
* addresses within the kernel image when built-in.
*/
static unsigned long mc_tmp_ptrs[MAX_UCODE_COUNT];
static struct mc_saved_data {
unsigned int num_saved;
struct microcode_intel **mc_saved;
} mc_saved_data;
/* Microcode blobs within the initrd. 0 if builtin. */
static struct ucode_blobs {
unsigned long start;
bool valid;
} blobs;
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++