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[PATCH] x86-64: Use symbolic CPU features in early CPUID check
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Dead to magic numbers!

Generated code is the same.

Signed-off-by: Andi Kleen <ak@suse.de>
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Andi Kleen authored and Andi Kleen committed May 2, 2007
1 parent 4637a74 commit 72b1b1d
Showing 1 changed file with 16 additions and 7 deletions.
23 changes: 16 additions & 7 deletions arch/x86_64/kernel/verify_cpu.S
Original file line number Diff line number Diff line change
Expand Up @@ -30,18 +30,27 @@
* appropriately. Either display a message or halt.
*/

verify_cpu:
#include <asm/cpufeature.h>

verify_cpu:
pushfl # Save caller passed flags
pushl $0 # Kill any dangerous flags
popfl

/* minimum CPUID flags for x86-64 */
/* see http://www.x86-64.org/lists/discuss/msg02971.html */
#define SSE_MASK ((1<<25)|(1<<26))
#define REQUIRED_MASK1 ((1<<0)|(1<<3)|(1<<4)|(1<<5)|(1<<6)|(1<<8)|\
(1<<13)|(1<<15)|(1<<24))
#define REQUIRED_MASK2 (1<<29)
/* minimum CPUID flags for x86-64 as defined by AMD */
#define M(x) (1<<(x))
#define M2(a,b) M(a)|M(b)
#define M4(a,b,c,d) M(a)|M(b)|M(c)|M(d)

#define SSE_MASK \
(M2(X86_FEATURE_XMM,X86_FEATURE_XMM2))
#define REQUIRED_MASK1 \
(M4(X86_FEATURE_FPU,X86_FEATURE_PSE,X86_FEATURE_TSC,X86_FEATURE_MSR)|\
M4(X86_FEATURE_PAE,X86_FEATURE_CX8,X86_FEATURE_PGE,X86_FEATURE_CMOV)|\
M(X86_FEATURE_FXSR))
#define REQUIRED_MASK2 \
(M(X86_FEATURE_LM - 32))

pushfl # standard way to check for cpuid
popl %eax
movl %eax,%ebx
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