diff options
Diffstat (limited to 'sysdeps/x86_64/multiarch/init-arch.c')
-rw-r--r-- | sysdeps/x86_64/multiarch/init-arch.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/sysdeps/x86_64/multiarch/init-arch.c b/sysdeps/x86_64/multiarch/init-arch.c new file mode 100644 index 0000000000..eb4365fe32 --- /dev/null +++ b/sysdeps/x86_64/multiarch/init-arch.c @@ -0,0 +1,65 @@ +/* Initialize CPU feature data. + This file is part of the GNU C Library. + Copyright (C) 2008 Free Software Foundation, Inc. + Contributed by Ulrich Drepper <drepper@redhat.com>. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include "init-arch.h" + + +struct cpu_features __cpu_features attribute_hidden; + + +void +__init_cpu_features (void) +{ + unsigned int ebx; + unsigned int ecx; + unsigned int edx; + + asm volatile ("cpuid" + : "=a" (__cpu_features.max_cpuid), "=b" (ebx), "=c" (ecx), + "=d" (edx) + : "0" (0)); + + /* This spells out "GenuineIntel". */ + if (ebx == 0x756e6547 && ecx == 0x6c65746e && edx == 0x49656e69) + { + __cpu_features.kind = arch_kind_intel; + + asm volatile ("cpuid" + : "=a" (__cpu_features.cpuid[INTEL_CPUID_INDEX_1].eax), + "=b" (__cpu_features.cpuid[INTEL_CPUID_INDEX_1].ebx), + "=c" (__cpu_features.cpuid[INTEL_CPUID_INDEX_1].ecx), + "=d" (__cpu_features.cpuid[INTEL_CPUID_INDEX_1].edx) + : "0" (1)); + } + /* This spells out "AuthenticAMD". */ + else if (ebx == 0x68747541 && ecx == 0x444d4163 && edx == 0x69746e65) + { + __cpu_features.kind = arch_kind_amd; + + asm volatile ("cpuid" + : "=a" (__cpu_features.cpuid[AMD_CPUID_INDEX_1].eax), + "=b" (__cpu_features.cpuid[AMD_CPUID_INDEX_1].ebx), + "=c" (__cpu_features.cpuid[AMD_CPUID_INDEX_1].ecx), + "=d" (__cpu_features.cpuid[AMD_CPUID_INDEX_1].edx) + : "0" (1)); + } + else + __cpu_features.kind = arch_kind_other; +} |