Merge commit 'v2.6.28-rc2' into core/locking
[linux-2.6] / arch / x86 / boot / cpu.c
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 #include "cpustr.h"
20
21 static char *cpu_name(int level)
22 {
23         static char buf[6];
24
25         if (level == 64) {
26                 return "x86-64";
27         } else {
28                 if (level == 15)
29                         level = 6;
30                 sprintf(buf, "i%d86", level);
31                 return buf;
32         }
33 }
34
35 int validate_cpu(void)
36 {
37         u32 *err_flags;
38         int cpu_level, req_level;
39         const unsigned char *msg_strs;
40
41         check_cpu(&cpu_level, &req_level, &err_flags);
42
43         if (cpu_level < req_level) {
44                 printf("This kernel requires an %s CPU, ",
45                        cpu_name(req_level));
46                 printf("but only detected an %s CPU.\n",
47                        cpu_name(cpu_level));
48                 return -1;
49         }
50
51         if (err_flags) {
52                 int i, j;
53                 puts("This kernel requires the following features "
54                      "not present on the CPU:\n");
55
56                 msg_strs = (const unsigned char *)x86_cap_strs;
57
58                 for (i = 0; i < NCAPINTS; i++) {
59                         u32 e = err_flags[i];
60
61                         for (j = 0; j < 32; j++) {
62                                 if (msg_strs[0] < i ||
63                                     (msg_strs[0] == i && msg_strs[1] < j)) {
64                                         /* Skip to the next string */
65                                         msg_strs += 2;
66                                         while (*msg_strs++)
67                                                 ;
68                                 }
69                                 if (e & 1) {
70                                         if (msg_strs[0] == i &&
71                                             msg_strs[1] == j &&
72                                             msg_strs[2])
73                                                 printf("%s ", msg_strs+2);
74                                         else
75                                                 printf("%d:%d ", i, j);
76                                 }
77                                 e >>= 1;
78                         }
79                 }
80                 putchar('\n');
81                 return -1;
82         } else {
83                 return 0;
84         }
85 }