minix/lib/libc/arch/i386/_cpufeature.c

   1 #include <sys/types.h>
   2 #include <stdint.h>
   3 #include <minix/minlib.h>
   4 #include <minix/cpufeature.h>
   5 #include <machine/vm.h>
   6 #include <string.h>
   7
   8 int _cpufeature(int cpufeature)
   9 {
  10         u32_t eax, ebx, ecx, edx;
  11         u32_t ef_eax = 0, ef_ebx = 0, ef_ecx = 0, ef_edx = 0;
  12         unsigned int family, model, stepping;
  13         int is_intel = 0, is_amd = 0;
  14
  15         eax = ebx = ecx = edx = 0;
  16
  17         /* We assume >= pentium for cpuid */
  18         eax = 0;
  19         _cpuid(&eax, &ebx, &ecx, &edx);
  20         if(eax > 0) {
  21                 char vendor[12];
  22                 memcpy(vendor,   &ebx, sizeof(ebx));
  23                 memcpy(vendor+4, &edx, sizeof(edx));
  24                 memcpy(vendor+8, &ecx, sizeof(ecx));
  25                 if(!strncmp(vendor, "GenuineIntel", sizeof(vendor)))
  26                         is_intel = 1;
  27                 if(!strncmp(vendor, "AuthenticAMD", sizeof(vendor)))
  28                         is_amd = 1;
  29                 eax = 1;
  30                 _cpuid(&eax, &ebx, &ecx, &edx);
  31         } else return 0;
  32
  33         stepping   =  eax        & 0xf;
  34         model    = (eax >>  4) & 0xf;
  35
  36         if(model == 0xf || model == 0x6) {
  37                 model += ((eax >> 16) & 0xf) << 4;
  38         }
  39
  40         family   = (eax >>  8) & 0xf;
  41
  42         if(family == 0xf) {
  43                 family += (eax >> 20) & 0xff;
  44         }
  45
  46         if(is_amd) {
  47                 ef_eax = 0x80000001;
  48                 _cpuid(&ef_eax, &ef_ebx, &ef_ecx, &ef_edx);
  49         }
  50
  51         switch(cpufeature) {
  52                 case _CPUF_I386_PSE:
  53                         return edx & CPUID1_EDX_PSE;
  54                 case _CPUF_I386_PAE:
  55                         return edx & CPUID1_EDX_PAE;
  56                 case _CPUF_I386_PGE:
  57                         return edx & CPUID1_EDX_PGE;
  58                 case _CPUF_I386_APIC_ON_CHIP:
  59                         return edx & CPUID1_EDX_APIC_ON_CHIP;
  60                 case _CPUF_I386_TSC:
  61                         return edx & CPUID1_EDX_TSC;
  62                 case _CPUF_I386_FPU:
  63                         return edx & CPUID1_EDX_FPU;
  64 #define SSE_FULL_EDX (CPUID1_EDX_FXSR | CPUID1_EDX_SSE | CPUID1_EDX_SSE2)
  65 #define SSE_FULL_ECX (CPUID1_ECX_SSE3 | CPUID1_ECX_SSSE3 | \
  66         CPUID1_ECX_SSE4_1 | CPUID1_ECX_SSE4_2)
  67                 case _CPUF_I386_SSE1234_12:
  68                         return  (edx & SSE_FULL_EDX) == SSE_FULL_EDX &&
  69                                 (ecx & SSE_FULL_ECX) == SSE_FULL_ECX;
  70                 case _CPUF_I386_FXSR:
  71                         return edx & CPUID1_EDX_FXSR;
  72                 case _CPUF_I386_SSE:
  73                         return edx & CPUID1_EDX_SSE;
  74                 case _CPUF_I386_SSE2:
  75                         return edx & CPUID1_EDX_SSE2;
  76                 case _CPUF_I386_SSE3:
  77                         return ecx & CPUID1_ECX_SSE3;
  78                 case _CPUF_I386_SSSE3:
  79                         return ecx & CPUID1_ECX_SSSE3;
  80                 case _CPUF_I386_SSE4_1:
  81                         return ecx & CPUID1_ECX_SSE4_1;
  82                 case _CPUF_I386_SSE4_2:
  83                         return ecx & CPUID1_ECX_SSE4_2;
  84                 case _CPUF_I386_HTT:
  85                         return edx & CPUID1_EDX_HTT;
  86                 case _CPUF_I386_HTT_MAX_NUM:
  87                         return (ebx >> 16) & 0xff;
  88                 case _CPUF_I386_SYSENTER:
  89                         if(!is_intel) return 0;
  90                         if(!(edx & CPUID1_EDX_SYSENTER)) return 0;
  91                         if(family == 6 && model < 3 && stepping < 3) return 0;
  92                         return 1;
  93                 case _CPUF_I386_SYSCALL:
  94                         if(!is_amd) return 0;
  95                         if(!(ef_edx & CPUID_EF_EDX_SYSENTER)) return 0;
  96                         return 1;
  97         }
  98
  99         return 0;
 100 }
 101