tests/mips_features.c

   1 // This file determines MIPS features a processor supports.
   2 //
   3 // We return:
   4 // - 0 if the machine matches the asked-for feature.
   5 // - 1 if the machine does not.
   6 // - 2 if the asked-for feature isn't recognised (this will be the case for
   7 //     any feature if run on a non-MIPS machine).
   8 // - 3 if there was a usage error (it also prints an error message).
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <assert.h>
  13
  14 #define FEATURE_PRESENT       0
  15 #define FEATURE_NOT_PRESENT   1
  16 #define UNRECOGNISED_FEATURE  2
  17 #define USAGE_ERROR           3
  18
  19 #if defined(VGA_mips32) || defined(VGA_mips64)
  20 static int mipsCPUInfo(const char *search_string) {
  21    const char *file_name = "/proc/cpuinfo";
  22    /* Simple detection of MIPS DSP ASE at runtime for Linux.
  23    * It is based on /proc/cpuinfo, which reveals hardware configuration
  24    * to user-space applications. */
  25
  26    char cpuinfo_line[256];
  27
  28    FILE *f = NULL;
  29    if ((f = fopen (file_name, "r")) == NULL)
  30      return 0;
  31
  32    while (fgets (cpuinfo_line, sizeof (cpuinfo_line), f) != NULL)
  33    {
  34      if (strstr (cpuinfo_line, search_string) != NULL)
  35      {
  36          fclose (f);
  37          return 1;
  38      }
  39    }
  40
  41    fclose (f);
  42
  43    /* Did not find string in the /proc/cpuinfo file. */
  44    return 0;
  45 }
  46
  47 static int go(char *feature)
  48 {
  49    int cpuinfo;
  50    if (strcmp(feature, "fpu") == 0) {
  51 #if defined(__mips_hard_float)
  52       /* This is not a runtime detection.
  53          If mips_features is built as hard-float, the assumption is that
  54          the target MIPS platform has a floating-point unit. */
  55       return FEATURE_PRESENT;
  56 #else
  57       return FEATURE_NOT_PRESENT;
  58 #endif
  59    }
  60    else if (strcmp(feature, "mips32-dsp") == 0) {
  61       const char *dsp = "dsp";
  62       cpuinfo = mipsCPUInfo(dsp);
  63       if (cpuinfo == 1) {
  64          return FEATURE_PRESENT;
  65       } else{
  66          return FEATURE_NOT_PRESENT;
  67       }
  68    } else if (strcmp(feature, "mips32-dspr2") == 0) {
  69       const char *dsp2 = "dsp2";
  70       cpuinfo = mipsCPUInfo(dsp2);
  71       if (cpuinfo == 1) {
  72          return FEATURE_PRESENT;
  73       } else{
  74          return FEATURE_NOT_PRESENT;
  75       }
  76    } else if (strcmp(feature, "cavium-octeon") == 0) {
  77       const char *cavium = "Cavium Octeon";
  78       cpuinfo = mipsCPUInfo(cavium);
  79       if (cpuinfo == 1) {
  80          return FEATURE_PRESENT;
  81       } else{
  82          return FEATURE_NOT_PRESENT;
  83       }
  84    } else if (strcmp(feature, "cavium-octeon2") == 0) {
  85       const char *cavium2 = "Cavium Octeon II";
  86       cpuinfo = mipsCPUInfo(cavium2);
  87       if (cpuinfo == 1) {
  88          return FEATURE_PRESENT;
  89       } else{
  90          return FEATURE_NOT_PRESENT;
  91       }
  92    } else if (strcmp(feature, "mips-be") == 0) {
  93 #if defined (_MIPSEB)
  94      return FEATURE_PRESENT;
  95 #else
  96      return FEATURE_NOT_PRESENT;
  97 #endif
  98    } else {
  99       return UNRECOGNISED_FEATURE;
 100    }
 101
 102 }
 103
 104 #else
 105
 106 static int go(char *feature)
 107 {
 108    /* Feature is not recognised. (non-MIPS machine!) */
 109    return UNRECOGNISED_FEATURE;
 110 }
 111
 112 #endif
 113
 114
 115 //---------------------------------------------------------------------------
 116 // main
 117 //---------------------------------------------------------------------------
 118 int main(int argc, char **argv)
 119 {
 120    if (argc != 2) {
 121       fprintf( stderr, "usage: mips_features <feature>\n" );
 122       exit(USAGE_ERROR);
 123    }
 124    return go(argv[1]);
 125 }