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)
20static 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
47static int go(char *feature)
48{
49   int cpuinfo;
50   if (strcmp(feature, "mips32-dsp") == 0) {
51      const char *dsp = "dsp";
52      cpuinfo = mipsCPUInfo(dsp);
53      if (cpuinfo == 1) {
54         return FEATURE_PRESENT;
55      } else{
56         return FEATURE_NOT_PRESENT;
57      }
58   } else if (strcmp(feature, "mips32-dspr2") == 0) {
59      const char *dsp2 = "dsp2";
60      cpuinfo = mipsCPUInfo(dsp2);
61      if (cpuinfo == 1) {
62         return FEATURE_PRESENT;
63      } else{
64         return FEATURE_NOT_PRESENT;
65      }
66   } else if (strcmp(feature, "cavium-octeon") == 0) {
67      const char *cavium = "Cavium Octeon";
68      cpuinfo = mipsCPUInfo(cavium);
69      if (cpuinfo == 1) {
70         return FEATURE_PRESENT;
71      } else{
72         return FEATURE_NOT_PRESENT;
73      }
74   } else if (strcmp(feature, "cavium-octeon2") == 0) {
75      const char *cavium2 = "Cavium Octeon II";
76      cpuinfo = mipsCPUInfo(cavium2);
77      if (cpuinfo == 1) {
78         return FEATURE_PRESENT;
79      } else{
80         return FEATURE_NOT_PRESENT;
81      }
82   } else if (strcmp(feature, "mips-be") == 0) {
83#if defined (_MIPSEB)
84     return FEATURE_PRESENT;
85#else
86     return FEATURE_NOT_PRESENT;
87#endif
88   } else {
89      return UNRECOGNISED_FEATURE;
90   }
91
92}
93
94#else
95
96static int go(char *feature)
97{
98   /* Feature is not recognised. (non-MIPS machine!) */
99   return UNRECOGNISED_FEATURE;
100}
101
102#endif
103
104
105//---------------------------------------------------------------------------
106// main
107//---------------------------------------------------------------------------
108int main(int argc, char **argv)
109{
110   if (argc != 2) {
111      fprintf( stderr, "usage: mips_features <feature>\n" );
112      exit(USAGE_ERROR);
113   }
114   return go(argv[1]);
115}
116