| #include <setjmp.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <assert.h> |
| |
| // This file determines s390x features a processor supports. |
| // |
| // We return: |
| // - 0 if the machine matches the asked-for feature. |
| // - 1 if the machine does not. |
| // - 2 if the asked-for feature isn't recognised (this will be the case for |
| // any feature if run on a non-s390x machine). |
| // - 3 if there was a usage error (it also prints an error message). |
| |
| jmp_buf env; |
| |
| #if defined(VGA_s390x) |
| |
| void handle_sigill(int signum) |
| { |
| longjmp(env, 1); |
| } |
| |
| unsigned long long stfle(void) |
| { |
| |
| unsigned long long ret; |
| |
| signal(SIGILL, handle_sigill); |
| if (setjmp(env)) { |
| /* stfle not available: assume no facilities */ |
| return 0; |
| } else { |
| asm volatile("lghi 0, 0\n" |
| ".insn s,0xb2b00000,%0\n" /* stfle */ |
| : "=Q" (ret)::"0", "cc"); |
| return ret; |
| } |
| } |
| |
| static int go(char* cpu) |
| { |
| unsigned long long facilities; |
| unsigned long long match; |
| |
| facilities = stfle(); |
| |
| if (strcmp(cpu, "s390x-zarch") == 0 ) { |
| match = (facilities & (1ULL << 62) && (facilities & (1ULL << 61))); |
| } else if (strcmp(cpu, "s390x-n3") == 0 ) { |
| match = (facilities & (1ULL << 63)); |
| } else if (strcmp(cpu, "s390x-stfle") == 0 ) { |
| match = (facilities & (1ULL << 56)); |
| } else if (strcmp(cpu, "s390x-ldisp") == 0 ) { |
| match = (facilities & (1ULL << 45) && (facilities & (1ULL << 44))); |
| } else if (strcmp(cpu, "s390x-eimm") == 0 ) { |
| match = (facilities & (1ULL << 42)); |
| } else if (strcmp(cpu, "s390x-stckf") == 0 ) { |
| match = (facilities & (1ULL << 38)); |
| } else if (strcmp(cpu, "s390x-genins") == 0 ) { |
| match = (facilities & (1ULL << 29)); |
| } else if (strcmp(cpu, "s390x-exrl") == 0 ) { |
| match = (facilities & (1ULL << 28)); |
| } else { |
| return 2; // Unrecognised feature. |
| } |
| |
| return match == 0; |
| } |
| |
| #else |
| |
| static int go(char* cpu) |
| { |
| return 2; // Feature not recognised (non-s390x machine!) |
| } |
| |
| #endif |
| |
| |
| //--------------------------------------------------------------------------- |
| // main |
| //--------------------------------------------------------------------------- |
| int main(int argc, char **argv) |
| { |
| if ( argc != 2 ) { |
| fprintf( stderr, "usage: s390x_features <feature>\n" ); |
| exit(3); // Usage error. |
| } |
| return go(argv[1]); |
| } |