1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007-2008 rPath, Inc. - All Rights Reserved
5 *
6 * This file is part of the Linux kernel, and is made available under
7 * the terms of the GNU General Public License version 2.
8 *
9 * ----------------------------------------------------------------------- */
10
11/*
12 * arch/x86/boot/cpu.c
13 *
14 * Check for obligatory CPU features and abort if the features are not
15 * present.
16 */
17
18#include "boot.h"
19#ifdef CONFIG_X86_FEATURE_NAMES
20#include "cpustr.h"
21#endif
22
23static char *cpu_name(int level)
24{
25 static char buf[6];
26
27 if (level == 64) {
28 return "x86-64";
29 } else {
30 if (level == 15)
31 level = 6;
32 sprintf(buf, "i%d86", level);
33 return buf;
34 }
35}
36
37static void show_cap_strs(u32 *err_flags)
38{
39 int i, j;
40#ifdef CONFIG_X86_FEATURE_NAMES
41 const unsigned char *msg_strs = (const unsigned char *)x86_cap_strs;
42 for (i = 0; i < NCAPINTS; i++) {
43 u32 e = err_flags[i];
44 for (j = 0; j < 32; j++) {
45 if (msg_strs[0] < i ||
46 (msg_strs[0] == i && msg_strs[1] < j)) {
47 /* Skip to the next string */
48 msg_strs += 2;
49 while (*msg_strs++)
50 ;
51 }
52 if (e & 1) {
53 if (msg_strs[0] == i &&
54 msg_strs[1] == j &&
55 msg_strs[2])
56 printf("%s ", msg_strs+2);
57 else
58 printf("%d:%d ", i, j);
59 }
60 e >>= 1;
61 }
62 }
63#else
64 for (i = 0; i < NCAPINTS; i++) {
65 u32 e = err_flags[i];
66 for (j = 0; j < 32; j++) {
67 if (e & 1)
68 printf("%d:%d ", i, j);
69 e >>= 1;
70 }
71 }
72#endif
73}
74
75int validate_cpu(void)
76{
77 u32 *err_flags;
78 int cpu_level, req_level;
79
80 check_cpu(&cpu_level, &req_level, &err_flags);
81
82 if (cpu_level < req_level) {
83 printf("This kernel requires an %s CPU, ",
84 cpu_name(req_level));
85 printf("but only detected an %s CPU.\n",
86 cpu_name(cpu_level));
87 return -1;
88 }
89
90 if (err_flags) {
91 puts("This kernel requires the following features "
92 "not present on the CPU:\n");
93 show_cap_strs(err_flags);
94 putchar('\n');
95 return -1;
96 } else if (check_knl_erratum()) {
97 return -1;
98 } else {
99 return 0;
100 }
101}
102