/* * GRUB -- GRand Unified Bootloader * Copyright (C) 2009 Free Software Foundation, Inc. * * GRUB is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * GRUB 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with GRUB. If not, see <http://www.gnu.org/licenses/>. */ #include <grub/efiemu/efiemu.h> #include <grub/machine/efiemu.h> #include <grub/command.h> #define cpuid(num,a,b,c,d) \ asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1" \ : "=a" (a), "=r" (b), "=c" (c), "=d" (d) \ : "0" (num)) #define bit_LM (1 << 29) char * grub_efiemu_get_default_core_name (void) { unsigned int eax, ebx, ecx, edx; unsigned int max_level; unsigned int ext_level; /* See if we can use cpuid. */ asm volatile ("pushfl; pushfl; popl %0; movl %0,%1; xorl %2,%0;" "pushl %0; popfl; pushfl; popl %0; popfl" : "=&r" (eax), "=&r" (ebx) : "i" (0x00200000)); if (((eax ^ ebx) & 0x00200000) == 0) return "efiemu32.o"; /* Check the highest input value for eax. */ cpuid (0, eax, ebx, ecx, edx); /* We only look at the first four characters. */ max_level = eax; if (max_level == 0) return "efiemu32.o"; cpuid (0x80000000, eax, ebx, ecx, edx); ext_level = eax; if (ext_level < 0x80000000) return "efiemu32.o"; cpuid (0x80000001, eax, ebx, ecx, edx); return (edx & bit_LM) ? "efiemu64.o" : "efiemu32.o"; }