tools/perf/arch/x86/util/header.c

   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
   9 static inline void
  10 cpuid(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
  22 int
  23 get_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 = snprintf(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 }