From 3829ee6b1be03d5aa3005fe7d19f30088b539836 Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Thu, 28 Jul 2005 21:15:48 -0700 Subject: [PATCH] x86_64: Small assembly improvements Save a byte here and there. Ultimatively useless, but these things always catch my eyes when reading the code so just fix them for now. Also I got at least one patch fixing of them already, which gives a good excuse. Signed-off-by: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/x86_64/kernel/head.S | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'arch/x86_64/kernel/head.S') diff --git a/arch/x86_64/kernel/head.S b/arch/x86_64/kernel/head.S index 8d765aa77a2..98ff5eb32b9 100644 --- a/arch/x86_64/kernel/head.S +++ b/arch/x86_64/kernel/head.S @@ -137,14 +137,14 @@ startup_64: wrmsr /* Setup cr0 */ - xorq %rax, %rax - btsq $31, %rax /* Enable paging */ - btsq $0, %rax /* Enable protected mode */ - btsq $1, %rax /* Enable MP */ - btsq $4, %rax /* Enable ET */ - btsq $5, %rax /* Enable NE */ - btsq $16, %rax /* Enable WP */ - btsq $18, %rax /* Enable AM */ +#define CR0_PM 1 /* protected mode */ +#define CR0_MP (1<<1) +#define CR0_ET (1<<4) +#define CR0_NE (1<<5) +#define CR0_WP (1<<16) +#define CR0_AM (1<<18) +#define CR0_PAGING (1<<31) + movl $CR0_PM|CR0_MP|CR0_ET|CR0_NE|CR0_WP|CR0_AM|CR0_PAGING,%eax /* Make changes effective */ movq %rax, %cr0 -- cgit v1.2.3