com32/sysdump/cpuid.c

   1 /*
   2  * Dump CPUID information
   3  */
   4
   5 #include <stdio.h>
   6 #include <string.h>
   7 #include <stdlib.h>
   8 #include <com32.h>
   9 #include <sys/cpu.h>
  10 #include "sysdump.h"
  11 #include "backend.h"
  12
  13 struct cpuid_data {
  14     uint32_t eax, ebx, ecx, edx;
  15 };
  16
  17 struct cpuid_info {
  18     uint32_t eax, ecx;
  19     struct cpuid_data data;
  20 };
  21
  22 static void get_cpuid(uint32_t eax, uint32_t ecx, struct cpuid_data *data)
  23 {
  24     asm("pushl %%ebx ; cpuid ; movl %%ebx,%1 ; popl %%ebx"
  25         : "=a" (data->eax), "=r" (data->ebx),
  26           "=c" (data->ecx), "=d" (data->edx)
  27         : "a" (eax), "c" (ecx));
  28 }
  29
  30 #define CPUID_CHUNK 128
  31
  32 void dump_cpuid(struct backend *be)
  33 {
  34     struct cpuid_info *buf = NULL;
  35     int nentry, nalloc;
  36     uint32_t region;
  37     struct cpuid_data base_leaf;
  38     uint32_t base, leaf, count;
  39     struct cpuid_data invalid_leaf;
  40     struct cpuid_data data;
  41
  42     if (!cpu_has_eflag(EFLAGS_ID))
  43         return;
  44
  45     printf("Dumping CPUID... ");
  46
  47     nentry = nalloc = 0;
  48
  49     /* Find out what the CPU returns for invalid leaves */
  50     get_cpuid(0, 0, &base_leaf);
  51     get_cpuid(base_leaf.eax+1, 0, &invalid_leaf);
  52
  53     for (region = 0 ; region <= 0xffff ; region++) {
  54         base = region << 16;
  55
  56         get_cpuid(base, 0, &base_leaf);
  57         if (region && !memcmp(&base_leaf, &invalid_leaf, sizeof base_leaf))
  58             continue;
  59
  60         if ((base_leaf.eax ^ base) & 0xffff0000)
  61             continue;
  62
  63         for (leaf = base ; leaf <= base_leaf.eax ; leaf++) {
  64             get_cpuid(leaf, 0, &data);
  65             count = 0;
  66
  67             do {
  68                 if (nentry >= nalloc) {
  69                     nalloc += CPUID_CHUNK;
  70                     buf = realloc(buf, nalloc*sizeof *buf);
  71                     if (!buf)
  72                         return;         /* FAILED */
  73                 }
  74                 buf[nentry].eax = leaf;
  75                 buf[nentry].ecx = count;
  76                 buf[nentry].data = data;
  77                 nentry++;
  78                 count++;
  79
  80                 get_cpuid(leaf, count, &data);
  81             } while (memcmp(&data, &buf[nentry-1].data, sizeof data) &&
  82                      (data.eax | data.ebx | data.ecx | data.edx));
  83         }
  84     }
  85
  86     if (nentry)
  87         cpio_writefile(be, "cpuid", buf, nentry*sizeof *buf);
  88     free(buf);
  89
  90     printf("done.\n");
  91 }