xref: /openbmc/linux/arch/x86/boot/cpu.c (revision 96ae6ea0)
1 /* -*- linux-c -*- ------------------------------------------------------- *
2  *
3  *   Copyright (C) 1991, 1992 Linus Torvalds
4  *   Copyright 2007 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/i386/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 "bitops.h"
20 #include <asm/cpufeature.h>
21 
22 static char *cpu_name(int level)
23 {
24 	static char buf[6];
25 
26 	if (level == 64) {
27 		return "x86-64";
28 	} else {
29 		sprintf(buf, "i%d86", level);
30 		return buf;
31 	}
32 }
33 
34 int validate_cpu(void)
35 {
36 	u32 *err_flags;
37 	int cpu_level, req_level;
38 
39 	check_cpu(&cpu_level, &req_level, &err_flags);
40 
41 	if (cpu_level < req_level) {
42 		printf("This kernel requires an %s CPU, ",
43 		       cpu_name(req_level));
44 		printf("but only detected an %s CPU.\n",
45 		       cpu_name(cpu_level));
46 		return -1;
47 	}
48 
49 	if (err_flags) {
50 		int i, j;
51 		puts("This kernel requires the following features "
52 		     "not present on the CPU:\n");
53 
54 		for (i = 0; i < NCAPINTS; i++) {
55 			u32 e = err_flags[i];
56 
57 			for (j = 0; j < 32; j++) {
58 				if (e & 1)
59 					printf("%d:%d ", i, j);
60 
61 				e >>= 1;
62 			}
63 		}
64 		putchar('\n');
65 		return -1;
66 	} else {
67 		return 0;
68 	}
69 }
70