1#include <sys/types.h>
2#include <unistd.h>
3#include <stdio.h>
4#include <stdlib.h>
5#include <string.h>
6
7#include "../../util/header.h"
8
9static inline void
10cpuid(unsigned int op, unsigned int *a, unsigned int *b, unsigned int *c,
11      unsigned int *d)
12{
13	__asm__ __volatile__ (".byte 0x53\n\tcpuid\n\t"
14			      "movl %%ebx, %%esi\n\t.byte 0x5b"
15			: "=a" (*a),
16			"=S" (*b),
17			"=c" (*c),
18			"=d" (*d)
19			: "a" (op));
20}
21
22int
23get_cpuid(char *buffer, size_t sz)
24{
25	unsigned int a, b, c, d, lvl;
26	int family = -1, model = -1, step = -1;
27	int nb;
28	char vendor[16];
29
30	cpuid(0, &lvl, &b, &c, &d);
31	strncpy(&vendor[0], (char *)(&b), 4);
32	strncpy(&vendor[4], (char *)(&d), 4);
33	strncpy(&vendor[8], (char *)(&c), 4);
34	vendor[12] = '\0';
35
36	if (lvl >= 1) {
37		cpuid(1, &a, &b, &c, &d);
38
39		family = (a >> 8) & 0xf;  /* bits 11 - 8 */
40		model  = (a >> 4) & 0xf;  /* Bits  7 - 4 */
41		step   = a & 0xf;
42
43		/* extended family */
44		if (family == 0xf)
45			family += (a >> 20) & 0xff;
46
47		/* extended model */
48		if (family >= 0x6)
49			model += ((a >> 16) & 0xf) << 4;
50	}
51	nb = scnprintf(buffer, sz, "%s,%u,%u,%u$", vendor, family, model, step);
52
53	/* look for end marker to ensure the entire data fit */
54	if (strchr(buffer, '$')) {
55		buffer[nb-1] = '\0';
56		return 0;
57	}
58	return -1;
59}
60