LXR linux/arch/x86/kernel/microcode_core

   1/*
   2 *      X86 CPU microcode early update for Linux
   3 *
   4 *      Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
   5 *                         H Peter Anvin" <hpa@zytor.com>
   6 *
   7 *      This driver allows to early upgrade microcode on Intel processors
   8 *      belonging to IA-32 family - PentiumPro, Pentium II,
   9 *      Pentium III, Xeon, Pentium 4, etc.
  10 *
  11 *      Reference: Section 9.11 of Volume 3, IA-32 Intel Architecture
  12 *      Software Developer's Manual.
  13 *
  14 *      This program is free software; you can redistribute it and/or
  15 *      modify it under the terms of the GNU General Public License
  16 *      as published by the Free Software Foundation; either version
  17 *      2 of the License, or (at your option) any later version.
  18 */
  19#include <linux/module.h>
  20#include <asm/microcode_intel.h>
  21#include <asm/processor.h>
  22
  23#define QCHAR(a, b, c, d) ((a) + ((b) << 8) + ((c) << 16) + ((d) << 24))
  24#define CPUID_INTEL1 QCHAR('G', 'e', 'n', 'u')
  25#define CPUID_INTEL2 QCHAR('i', 'n', 'e', 'I')
  26#define CPUID_INTEL3 QCHAR('n', 't', 'e', 'l')
  27#define CPUID_AMD1 QCHAR('A', 'u', 't', 'h')
  28#define CPUID_AMD2 QCHAR('e', 'n', 't', 'i')
  29#define CPUID_AMD3 QCHAR('c', 'A', 'M', 'D')
  30
  31#define CPUID_IS(a, b, c, ebx, ecx, edx)        \
  32                (!((ebx ^ (a))|(edx ^ (b))|(ecx ^ (c))))
  33
  34/*
  35 * In early loading microcode phase on BSP, boot_cpu_data is not set up yet.
  36 * x86_vendor() gets vendor id for BSP.
  37 *
  38 * In 32 bit AP case, accessing boot_cpu_data needs linear address. To simplify
  39 * coding, we still use x86_vendor() to get vendor id for AP.
  40 *
  41 * x86_vendor() gets vendor information directly through cpuid.
  42 */
  43static int __cpuinit x86_vendor(void)
  44{
  45        u32 eax = 0x00000000;
  46        u32 ebx, ecx = 0, edx;
  47
  48        native_cpuid(&eax, &ebx, &ecx, &edx);
  49
  50        if (CPUID_IS(CPUID_INTEL1, CPUID_INTEL2, CPUID_INTEL3, ebx, ecx, edx))
  51                return X86_VENDOR_INTEL;
  52
  53        if (CPUID_IS(CPUID_AMD1, CPUID_AMD2, CPUID_AMD3, ebx, ecx, edx))
  54                return X86_VENDOR_AMD;
  55
  56        return X86_VENDOR_UNKNOWN;
  57}
  58
  59static int __cpuinit x86_family(void)
  60{
  61        u32 eax = 0x00000001;
  62        u32 ebx, ecx = 0, edx;
  63        int x86;
  64
  65        native_cpuid(&eax, &ebx, &ecx, &edx);
  66
  67        x86 = (eax >> 8) & 0xf;
  68        if (x86 == 15)
  69                x86 += (eax >> 20) & 0xff;
  70
  71        return x86;
  72}
  73
  74void __init load_ucode_bsp(void)
  75{
  76        int vendor, x86;
  77
  78        if (!have_cpuid_p())
  79                return;
  80
  81        vendor = x86_vendor();
  82        x86 = x86_family();
  83
  84        if (vendor == X86_VENDOR_INTEL && x86 >= 6)
  85                load_ucode_intel_bsp();
  86}
  87
  88void __cpuinit load_ucode_ap(void)
  89{
  90        int vendor, x86;
  91
  92        if (!have_cpuid_p())
  93                return;
  94
  95        vendor = x86_vendor();
  96        x86 = x86_family();
  97
  98        if (vendor == X86_VENDOR_INTEL && x86 >= 6)
  99                load_ucode_intel_ap();
 100}
 101