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			126 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			126 lines
		
	
	
		
			3.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* cpuid.c - test for CPU features */
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| /*
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|  *  GRUB  --  GRand Unified Bootloader
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|  *  Copyright (C) 2006, 2007, 2009  Free Software Foundation, Inc.
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|  *  Based on gcc/gcc/config/i386/driver-i386.c
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|  *
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|  *  GRUB is free software: you can redistribute it and/or modify
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|  *  it under the terms of the GNU General Public License as published by
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|  *  the Free Software Foundation, either version 3 of the License, or
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|  *  (at your option) any later version.
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|  *
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|  *  GRUB is distributed in the hope that it will be useful,
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|  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|  *  GNU General Public License for more details.
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|  *
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|  *  You should have received a copy of the GNU General Public License
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|  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
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|  */
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| 
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| #include <grub/dl.h>
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| #include <grub/misc.h>
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| #include <grub/mm.h>
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| #include <grub/env.h>
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| #include <grub/command.h>
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| #include <grub/extcmd.h>
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| #include <grub/i386/cpuid.h>
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| #include <grub/i18n.h>
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| 
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| GRUB_MOD_LICENSE ("GPLv3+");
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| 
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| static const struct grub_arg_option options[] =
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|   {
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|     /* TRANSLATORS: "(default)" at the end means that this option is used if
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|        no argument is specified.  */
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|     {"long-mode", 'l', 0, N_("Check if CPU supports 64-bit (long) mode (default)."), 0, 0},
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|     {"pae", 'p', 0, N_("Check if CPU supports Physical Address Extension."), 0, 0},
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|     {0, 0, 0, 0, 0, 0}
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|   };
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| 
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| enum
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|   {
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|     MODE_LM = 0,
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|     MODE_PAE = 1
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|   };
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| 
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| enum
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|   {
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|     bit_PAE = (1 << 6),
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|   };
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| enum
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|   {
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|     bit_LM = (1 << 29)
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|   };
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| 
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| unsigned char grub_cpuid_has_longmode = 0, grub_cpuid_has_pae = 0;
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| 
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| static grub_err_t
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| grub_cmd_cpuid (grub_extcmd_context_t ctxt,
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| 		int argc __attribute__ ((unused)),
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| 		char **args __attribute__ ((unused)))
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| {
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|   int val = 0;
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|   if (ctxt->state[MODE_PAE].set)
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|     val = grub_cpuid_has_pae;
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|   else
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|     val = grub_cpuid_has_longmode;
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|   return val ? GRUB_ERR_NONE
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|     /* TRANSLATORS: it's a standalone boolean value,
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|        opposite of "true".  */
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|     : grub_error (GRUB_ERR_TEST_FAILURE, N_("false"));
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| }
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| 
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| static grub_extcmd_t cmd;
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| 
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| GRUB_MOD_INIT(cpuid)
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| {
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| #ifdef __x86_64__
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|   /* grub-emu */
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|   grub_cpuid_has_longmode = 1;
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|   grub_cpuid_has_pae = 1;
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| #else
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|   unsigned int eax, ebx, ecx, edx;
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|   unsigned int max_level;
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|   unsigned int ext_level;
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| 
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|   /* See if we can use cpuid.  */
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|   asm volatile ("pushfl; pushfl; popl %0; movl %0,%1; xorl %2,%0;"
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| 		"pushl %0; popfl; pushfl; popl %0; popfl"
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| 		: "=&r" (eax), "=&r" (ebx)
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| 		: "i" (0x00200000));
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|   if (((eax ^ ebx) & 0x00200000) == 0)
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|     goto done;
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| 
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|   /* Check the highest input value for eax.  */
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|   grub_cpuid (0, eax, ebx, ecx, edx);
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|   /* We only look at the first four characters.  */
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|   max_level = eax;
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|   if (max_level == 0)
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|     goto done;
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| 
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|   if (max_level >= 1)
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|     {
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|       grub_cpuid (1, eax, ebx, ecx, edx);
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|       grub_cpuid_has_pae = !!(edx & bit_PAE);
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|     }
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| 
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|   grub_cpuid (0x80000000, eax, ebx, ecx, edx);
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|   ext_level = eax;
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|   if (ext_level < 0x80000000)
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|     goto done;
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| 
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|   grub_cpuid (0x80000001, eax, ebx, ecx, edx);
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|   grub_cpuid_has_longmode = !!(edx & bit_LM);
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| done:
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| #endif
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| 
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|   cmd = grub_register_extcmd ("cpuid", grub_cmd_cpuid, 0,
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| 			      "[-l]", N_("Check for CPU features."), options);
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| }
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| 
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| GRUB_MOD_FINI(cpuid)
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| {
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|   grub_unregister_extcmd (cmd);
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| }
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