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	 cfaa71ee97
			
		
	
	
		cfaa71ee97
		
	
	
	
	
		
			
			Use symbolic MSR names instead of hardcoding the MSR index. Signed-off-by: Brian Gerst <brgerst@gmail.com> LKML-Reference: <1279371808-24804-2-git-send-email-brgerst@gmail.com> Reviewed-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
		
			
				
	
	
		
			107 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			107 lines
		
	
	
		
			2.8 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  *
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|  *	verify_cpu.S - Code for cpu long mode and SSE verification. This
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|  *	code has been borrowed from boot/setup.S and was introduced by
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|  * 	Andi Kleen.
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|  *
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|  *	Copyright (c) 2007  Andi Kleen (ak@suse.de)
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|  *	Copyright (c) 2007  Eric Biederman (ebiederm@xmission.com)
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|  *	Copyright (c) 2007  Vivek Goyal (vgoyal@in.ibm.com)
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|  *
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|  * 	This source code is licensed under the GNU General Public License,
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|  * 	Version 2.  See the file COPYING for more details.
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|  *
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|  *	This is a common code for verification whether CPU supports
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|  * 	long mode and SSE or not. It is not called directly instead this
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|  *	file is included at various places and compiled in that context.
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|  * 	Following are the current usage.
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|  *
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|  * 	This file is included by both 16bit and 32bit code.
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|  *
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|  *	arch/x86_64/boot/setup.S : Boot cpu verification (16bit)
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|  *	arch/x86_64/boot/compressed/head.S: Boot cpu verification (32bit)
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|  *	arch/x86_64/kernel/trampoline.S: secondary processor verfication (16bit)
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|  *	arch/x86_64/kernel/acpi/wakeup.S:Verfication at resume (16bit)
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|  *
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|  *	verify_cpu, returns the status of cpu check in register %eax.
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|  *		0: Success    1: Failure
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|  *
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|  * 	The caller needs to check for the error code and take the action
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|  * 	appropriately. Either display a message or halt.
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|  */
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| 
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| #include <asm/cpufeature.h>
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| #include <asm/msr-index.h>
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| 
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| verify_cpu:
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| 	pushfl				# Save caller passed flags
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| 	pushl	$0			# Kill any dangerous flags
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| 	popfl
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| 
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| 	pushfl				# standard way to check for cpuid
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| 	popl	%eax
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| 	movl	%eax,%ebx
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| 	xorl	$0x200000,%eax
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| 	pushl	%eax
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| 	popfl
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| 	pushfl
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| 	popl	%eax
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| 	cmpl	%eax,%ebx
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| 	jz	verify_cpu_no_longmode	# cpu has no cpuid
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| 
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| 	movl	$0x0,%eax		# See if cpuid 1 is implemented
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| 	cpuid
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| 	cmpl	$0x1,%eax
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| 	jb	verify_cpu_no_longmode	# no cpuid 1
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| 
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| 	xor	%di,%di
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| 	cmpl	$0x68747541,%ebx	# AuthenticAMD
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| 	jnz	verify_cpu_noamd
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| 	cmpl	$0x69746e65,%edx
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| 	jnz	verify_cpu_noamd
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| 	cmpl	$0x444d4163,%ecx
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| 	jnz	verify_cpu_noamd
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| 	mov	$1,%di			# cpu is from AMD
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| 
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| verify_cpu_noamd:
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| 	movl    $0x1,%eax		# Does the cpu have what it takes
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| 	cpuid
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| 	andl	$REQUIRED_MASK0,%edx
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| 	xorl	$REQUIRED_MASK0,%edx
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| 	jnz	verify_cpu_no_longmode
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| 
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| 	movl    $0x80000000,%eax	# See if extended cpuid is implemented
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| 	cpuid
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| 	cmpl    $0x80000001,%eax
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| 	jb      verify_cpu_no_longmode	# no extended cpuid
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| 
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| 	movl    $0x80000001,%eax	# Does the cpu have what it takes
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| 	cpuid
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| 	andl    $REQUIRED_MASK1,%edx
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| 	xorl    $REQUIRED_MASK1,%edx
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| 	jnz     verify_cpu_no_longmode
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| 
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| verify_cpu_sse_test:
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| 	movl	$1,%eax
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| 	cpuid
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| 	andl	$SSE_MASK,%edx
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| 	cmpl	$SSE_MASK,%edx
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| 	je	verify_cpu_sse_ok
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| 	test	%di,%di
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| 	jz	verify_cpu_no_longmode	# only try to force SSE on AMD
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| 	movl	$MSR_K7_HWCR,%ecx
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| 	rdmsr
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| 	btr	$15,%eax		# enable SSE
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| 	wrmsr
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| 	xor	%di,%di			# don't loop
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| 	jmp	verify_cpu_sse_test	# try again
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| 
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| verify_cpu_no_longmode:
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| 	popfl				# Restore caller passed flags
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| 	movl $1,%eax
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| 	ret
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| verify_cpu_sse_ok:
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| 	popfl				# Restore caller passed flags
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| 	xorl %eax, %eax
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| 	ret
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