diff options
author | Richard Henderson <rth@twiddle.net> | 2013-06-07 07:43:33 -0700 |
---|---|---|
committer | Richard Henderson <rth@twiddle.net> | 2013-11-30 07:45:30 +1300 |
commit | c9baa30f42a87f61627391698f63fa4d1566d9d8 (patch) | |
tree | 012f352b06ae68c761a7f6f39ef81b1731407843 /tcg/s390 | |
parent | 41d9ea80ac8455845494c889fe6ac447b39a7d64 (diff) |
tcg-s390: Use qemu_getauxval in query_facilities
No need to set up a SIGILL signal handler for detection anymore.
Remove a ton of sanity checks that must be true, given that we're
requiring a 64-bit build (the note about 31-bit KVM is satisfied
by configuring with TCI).
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg/s390')
-rw-r--r-- | tcg/s390/tcg-target.c | 95 |
1 files changed, 12 insertions, 83 deletions
diff --git a/tcg/s390/tcg-target.c b/tcg/s390/tcg-target.c index 0a4f3be0e9..248726e82f 100644 --- a/tcg/s390/tcg-target.c +++ b/tcg/s390/tcg-target.c @@ -31,6 +31,8 @@ #error "unsupported code generation mode" #endif +#include "elf.h" + /* ??? The translation blocks produced by TCG are generally small enough to be entirely reachable with a 16-bit displacement. Leaving the option for a 32-bit displacement here Just In Case. */ @@ -2233,91 +2235,18 @@ static void sigill_handler(int sig) static void query_facilities(void) { - struct sigaction sa_old, sa_new; - register int r0 __asm__("0"); - register void *r1 __asm__("1"); - int fail; - - memset(&sa_new, 0, sizeof(sa_new)); - sa_new.sa_handler = sigill_handler; - sigaction(SIGILL, &sa_new, &sa_old); - - /* First, try STORE FACILITY LIST EXTENDED. If this is present, then - we need not do any more probing. Unfortunately, this itself is an - extension and the original STORE FACILITY LIST instruction is - kernel-only, storing its results at absolute address 200. */ - /* stfle 0(%r1) */ - r1 = &facilities; - asm volatile(".word 0xb2b0,0x1000" - : "=r"(r0) : "0"(0), "r"(r1) : "memory", "cc"); - - if (got_sigill) { - /* STORE FACILITY EXTENDED is not available. Probe for one of each - kind of instruction that we're interested in. */ - /* ??? Possibly some of these are in practice never present unless - the store-facility-extended facility is also present. But since - that isn't documented it's just better to probe for each. */ - - /* Test for z/Architecture. Required even in 31-bit mode. */ - got_sigill = 0; - /* agr %r0,%r0 */ - asm volatile(".word 0xb908,0x0000" : "=r"(r0) : : "cc"); - if (!got_sigill) { - facilities |= FACILITY_ZARCH_ACTIVE; - } - - /* Test for long displacement. */ - got_sigill = 0; - /* ly %r0,0(%r1) */ - r1 = &facilities; - asm volatile(".word 0xe300,0x1000,0x0058" - : "=r"(r0) : "r"(r1) : "cc"); - if (!got_sigill) { - facilities |= FACILITY_LONG_DISP; - } - - /* Test for extended immediates. */ - got_sigill = 0; - /* afi %r0,0 */ - asm volatile(".word 0xc209,0x0000,0x0000" : : : "cc"); - if (!got_sigill) { - facilities |= FACILITY_EXT_IMM; - } - - /* Test for general-instructions-extension. */ - got_sigill = 0; - /* msfi %r0,1 */ - asm volatile(".word 0xc201,0x0000,0x0001"); - if (!got_sigill) { - facilities |= FACILITY_GEN_INST_EXT; - } - } - - sigaction(SIGILL, &sa_old, NULL); + unsigned long hwcap = qemu_getauxval(AT_HWCAP); - /* The translator currently uses these extensions unconditionally. - Pruning this back to the base ESA/390 architecture doesn't seem - worthwhile, since even the KVM target requires z/Arch. */ - fail = 0; - if ((facilities & FACILITY_ZARCH_ACTIVE) == 0) { - fprintf(stderr, "TCG: z/Arch facility is required.\n"); - fprintf(stderr, "TCG: Boot with a 64-bit enabled kernel.\n"); - fail = 1; - } - if ((facilities & FACILITY_LONG_DISP) == 0) { - fprintf(stderr, "TCG: long-displacement facility is required.\n"); - fail = 1; - } + /* Is STORE FACILITY LIST EXTENDED available? Honestly, I believe this + is present on all 64-bit systems, but let's check for it anyway. */ + if (hwcap & HWCAP_S390_STFLE) { + register int r0 __asm__("0"); + register void *r1 __asm__("1"); - /* So far there's just enough support for 31-bit mode to let the - compile succeed. This is good enough to run QEMU with KVM. */ - if (sizeof(void *) != 8) { - fprintf(stderr, "TCG: 31-bit mode is not supported.\n"); - fail = 1; - } - - if (fail) { - exit(-1); + /* stfle 0(%r1) */ + r1 = &facilities; + asm volatile(".word 0xb2b0,0x1000" + : "=r"(r0) : "0"(0), "r"(r1) : "memory", "cc"); } } |