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)
mipsCPUInfo(const char * search_string)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
go(char * feature)47 static 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
go(char * feature)96 static 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 //---------------------------------------------------------------------------
main(int argc,char ** argv)108 int 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