aboutsummaryrefslogtreecommitdiffhomepage
path: root/cpudetect.c
blob: 8fdf488dbf4bae476cc6884e1e6c16462f76d822 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
#include "config.h"
#include "cpudetect.h"

CpuCaps gCpuCaps;

#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif
#include <stdlib.h>

#ifdef ARCH_X86

#include <stdio.h>

#ifdef __FreeBSD__
#include <sys/types.h>
#include <sys/sysctl.h>
#endif

#ifdef __linux__
#include <signal.h>
#endif

//#define X86_FXSR_MAGIC
/* Thanks to the FreeBSD project for some of this cpuid code, and 
 * help understanding how to use it.  Thanks to the Mesa 
 * team for SSE support detection and more cpu detect code.
 */

/* I believe this code works.  However, it has only been used on a PII and PIII */

static void check_os_katmai_support( void );

#if 1
// return TRUE if cpuid supported
static int has_cpuid()
{
	int a, c;

// code from libavcodec:
    __asm__ __volatile__ (
                          /* See if CPUID instruction is supported ... */
                          /* ... Get copies of EFLAGS into eax and ecx */
                          "pushf\n\t"
                          "popl %0\n\t"
                          "movl %0, %1\n\t"
                          
                          /* ... Toggle the ID bit in one copy and store */
                          /*     to the EFLAGS reg */
                          "xorl $0x200000, %0\n\t"
                          "push %0\n\t"
                          "popf\n\t"
                          
                          /* ... Get the (hopefully modified) EFLAGS */
                          "pushf\n\t"
                          "popl %0\n\t"
                          : "=a" (a), "=c" (c)
                          :
                          : "cc" 
                          );

	return (a!=c);
}
#endif

static void
do_cpuid(unsigned int ax, unsigned int *p)
{
#if 0
	__asm __volatile(
	"cpuid;"
	: "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
	:  "0" (ax)
	);
#else
// code from libavcodec:
    __asm __volatile
	("movl %%ebx, %%esi\n\t"
         "cpuid\n\t"
         "xchgl %%ebx, %%esi"
         : "=a" (p[0]), "=S" (p[1]), 
           "=c" (p[2]), "=d" (p[3])
         : "0" (ax));
#endif

}

void GetCpuCaps( CpuCaps *caps)
{
	unsigned int regs[4];
	unsigned int regs2[4];

	caps->isX86=1;

	memset(caps, 0, sizeof(*caps));
	if (!has_cpuid()) {
	    printf("CPUID not supported!???\n");
	    return;
	}
	do_cpuid(0x00000000, regs); // get _max_ cpuid level and vendor name
	printf("CPU vendor name: %.4s%.4s%.4s  max cpuid level: %d\n",
			(char*) (regs+1),(char*) (regs+3),(char*) (regs+2), regs[0]);
	if (regs[0]>=0x00000001)
	{
		char *tmpstr;

		do_cpuid(0x00000001, regs2);

		tmpstr=GetCpuFriendlyName(regs, regs2);
		printf("CPU: %s ",tmpstr);
		free(tmpstr);

		caps->cpuType=(regs2[0] >> 8)&0xf;
		if(caps->cpuType==0xf){
		    // use extended family (P4, IA64)
		    caps->cpuType=8+((regs2[0]>>20)&255);
		}
		caps->cpuStepping=regs2[0] & 0xf;
		printf("(Type: %d, Stepping: %d)\n",
		    caps->cpuType, caps->cpuStepping);

		// general feature flags:
		caps->hasMMX  = (regs2[3] & (1 << 23 )) >> 23; // 0x0800000
		caps->hasSSE  = (regs2[3] & (1 << 25 )) >> 25; // 0x2000000
		caps->hasSSE2 = (regs2[3] & (1 << 26 )) >> 26; // 0x4000000
		caps->hasMMX2 = caps->hasSSE; // SSE cpus supports mmxext too
	}
	do_cpuid(0x80000000, regs);
	if (regs[0]>=0x80000001) {
		printf("extended cpuid-level: %d\n",regs[0]&0x7FFFFFFF);
		do_cpuid(0x80000001, regs2);
		caps->hasMMX  |= (regs2[3] & (1 << 23 )) >> 23; // 0x0800000
		caps->hasMMX2 |= (regs2[3] & (1 << 22 )) >> 22; // 0x400000
		caps->has3DNow    = (regs2[3] & (1 << 31 )) >> 31; //0x80000000
		caps->has3DNowExt = (regs2[3] & (1 << 30 )) >> 30;
	}
#if 0
	printf("cpudetect: MMX=%d MMX2=%d SSE=%d SSE2=%d 3DNow=%d 3DNowExt=%d\n",
		gCpuCaps.hasMMX,
		gCpuCaps.hasMMX2,
		gCpuCaps.hasSSE,
		gCpuCaps.hasSSE2,
		gCpuCaps.has3DNow,
		gCpuCaps.has3DNowExt );
#endif

		/* FIXME: Does SSE2 need more OS support, too? */
#if defined(__linux__) || defined(__FreeBSD__)
		if (caps->hasSSE)
			check_os_katmai_support();
		if (!caps->hasSSE)
			caps->hasSSE2 = 0;
#else
		caps->hasSSE=0;
		caps->hasSSE2 = 0;
#endif
//		caps->has3DNow=1;
//		caps->hasMMX2 = 0;
//		caps->hasMMX = 0;

}


#define CPUID_EXTFAMILY	((regs2[0] >> 20)&0xFF) /* 27..20 */
#define CPUID_EXTMODEL	((regs2[0] >> 16)&0x0F) /* 19..16 */
#define CPUID_TYPE		((regs2[0] >> 12)&0x04) /* 13..12 */
#define CPUID_FAMILY	((regs2[0] >>  8)&0x0F) /* 11..08 */
#define CPUID_MODEL		((regs2[0] >>  4)&0x0F) /* 07..04 */
#define CPUID_STEPPING	((regs2[0] >>  0)&0x0F) /* 03..00 */

char *GetCpuFriendlyName(unsigned int regs[], unsigned int regs2[]){
#include "cputable.h" /* get cpuname and cpuvendors */
	char vendor[17];
	char *retname;
	int i;

	if (NULL==(retname=(char*)malloc(256))) {
		printf("Error: GetCpuFriendlyName() not enough memory\n");
		exit(1);
	}

	sprintf(vendor,"%.4s%.4s%.4s",(char*)(regs+1),(char*)(regs+3),(char*)(regs+2));

	for(i=0; i<MAX_VENDORS; i++){
		if(!strcmp(cpuvendors[i].string,vendor)){
			if(cpuname[i][CPUID_FAMILY][CPUID_MODEL]){
				snprintf(retname,255,"%s %s",cpuvendors[i].name,cpuname[i][CPUID_FAMILY][CPUID_MODEL]);
			} else {
				snprintf(retname,255,"unknown %s %d. Generation CPU",cpuvendors[i].name,CPUID_FAMILY); 
				printf("unknown %s CPU:\n",cpuvendors[i].name);
				printf("Vendor:   %s\n",cpuvendors[i].string);
				printf("Type:     %d\n",CPUID_TYPE);
				printf("Family:   %d (ext: %d)\n",CPUID_FAMILY,CPUID_EXTFAMILY);
				printf("Model:    %d (ext: %d)\n",CPUID_MODEL,CPUID_EXTMODEL);
				printf("Stepping: %d\n",CPUID_STEPPING);
				printf("Please send the above info along with the exact CPU name"
				       "to the MPlayer-Developers, so we can add it to the list!\n");
			}
		}
	}

	//printf("Detected CPU: %s\n", retname);
	return retname;
}

#undef CPUID_EXTFAMILY
#undef CPUID_EXTMODEL
#undef CPUID_TYPE
#undef CPUID_FAMILY
#undef CPUID_MODEL
#undef CPUID_STEPPING


#if defined(__linux__) && defined(_POSIX_SOURCE) && defined(X86_FXSR_MAGIC)
static void sigill_handler_sse( int signal, struct sigcontext sc )
{
   printf( "SIGILL, " );

   /* Both the "xorps %%xmm0,%%xmm0" and "divps %xmm0,%%xmm1"
    * instructions are 3 bytes long.  We must increment the instruction
    * pointer manually to avoid repeated execution of the offending
    * instruction.
    *
    * If the SIGILL is caused by a divide-by-zero when unmasked
    * exceptions aren't supported, the SIMD FPU status and control
    * word will be restored at the end of the test, so we don't need
    * to worry about doing it here.  Besides, we may not be able to...
    */
   sc.eip += 3;

   gCpuCaps.hasSSE=0;
}

static void sigfpe_handler_sse( int signal, struct sigcontext sc )
{
   printf( "SIGFPE, " );

   if ( sc.fpstate->magic != 0xffff ) {
      /* Our signal context has the extended FPU state, so reset the
       * divide-by-zero exception mask and clear the divide-by-zero
       * exception bit.
       */
      sc.fpstate->mxcsr |= 0x00000200;
      sc.fpstate->mxcsr &= 0xfffffffb;
   } else {
      /* If we ever get here, we're completely hosed.
       */
      printf( "\n\n" );
      printf( "SSE enabling test failed badly!" );
   }
}
#endif /* __linux__ && _POSIX_SOURCE && X86_FXSR_MAGIC */

/* If we're running on a processor that can do SSE, let's see if we
 * are allowed to or not.  This will catch 2.4.0 or later kernels that
 * haven't been configured for a Pentium III but are running on one,
 * and RedHat patched 2.2 kernels that have broken exception handling
 * support for user space apps that do SSE.
 */
static void check_os_katmai_support( void )
{
#if defined(__FreeBSD__)
   int has_sse=0, ret;
   size_t len=sizeof(has_sse);

   ret = sysctlbyname("hw.instruction_sse", &has_sse, &len, NULL, 0);
   if (ret || !has_sse)
      gCpuCaps.hasSSE=0;

#elif defined(__linux__)
#if defined(_POSIX_SOURCE) && defined(X86_FXSR_MAGIC)
   struct sigaction saved_sigill;
   struct sigaction saved_sigfpe;

   /* Save the original signal handlers.
    */
   sigaction( SIGILL, NULL, &saved_sigill );
   sigaction( SIGFPE, NULL, &saved_sigfpe );

   signal( SIGILL, (void (*)(int))sigill_handler_sse );
   signal( SIGFPE, (void (*)(int))sigfpe_handler_sse );

   /* Emulate test for OSFXSR in CR4.  The OS will set this bit if it
    * supports the extended FPU save and restore required for SSE.  If
    * we execute an SSE instruction on a PIII and get a SIGILL, the OS
    * doesn't support Streaming SIMD Exceptions, even if the processor
    * does.
    */
   if ( gCpuCaps.hasSSE ) {
      printf( "Testing OS support for SSE... " );

//      __asm __volatile ("xorps %%xmm0, %%xmm0");
      __asm __volatile ("xorps %xmm0, %xmm0");

      if ( gCpuCaps.hasSSE ) {
	 printf( "yes.\n" );
      } else {
	 printf( "no!\n" );
      }
   }

   /* Emulate test for OSXMMEXCPT in CR4.  The OS will set this bit if
    * it supports unmasked SIMD FPU exceptions.  If we unmask the
    * exceptions, do a SIMD divide-by-zero and get a SIGILL, the OS
    * doesn't support unmasked SIMD FPU exceptions.  If we get a SIGFPE
    * as expected, we're okay but we need to clean up after it.
    *
    * Are we being too stringent in our requirement that the OS support
    * unmasked exceptions?  Certain RedHat 2.2 kernels enable SSE by
    * setting CR4.OSFXSR but don't support unmasked exceptions.  Win98
    * doesn't even support them.  We at least know the user-space SSE
    * support is good in kernels that do support unmasked exceptions,
    * and therefore to be safe I'm going to leave this test in here.
    */
   if ( gCpuCaps.hasSSE ) {
      printf( "Testing OS support for SSE unmasked exceptions... " );

//      test_os_katmai_exception_support();

      if ( gCpuCaps.hasSSE ) {
	 printf( "yes.\n" );
      } else {
	 printf( "no!\n" );
      }
   }

   /* Restore the original signal handlers.
    */
   sigaction( SIGILL, &saved_sigill, NULL );
   sigaction( SIGFPE, &saved_sigfpe, NULL );

   /* If we've gotten to here and the XMM CPUID bit is still set, we're
    * safe to go ahead and hook out the SSE code throughout Mesa.
    */
   if ( gCpuCaps.hasSSE ) {
      printf( "Tests of OS support for SSE passed.\n" );
   } else {
      printf( "Tests of OS support for SSE failed!\n" );
   }
#else
   /* We can't use POSIX signal handling to test the availability of
    * SSE, so we disable it by default.
    */
   printf( "Cannot test OS support for SSE, disabling to be safe.\n" );
   gCpuCaps.hasSSE=0;
#endif /* _POSIX_SOURCE && X86_FXSR_MAGIC */
#else
   /* Do nothing on other platforms for now.
    */
   printf( "Not testing OS support for SSE, leaving disabled.\n" );
   gCpuCaps.hasSSE=0;
#endif /* __linux__ */
}
#else /* ARCH_X86 */

void GetCpuCaps( CpuCaps *caps)
{
	caps->cpuType=0;
	caps->cpuStepping=0;
	caps->hasMMX=0;
	caps->hasMMX2=0;
	caps->has3DNow=0;
	caps->has3DNowExt=0;
	caps->hasSSE=0;
	caps->hasSSE2=0;
	caps->isX86=0;
}
#endif /* !ARCH_X86 */