Linux Kernel  3.7.1
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cpu.c
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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 }