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authorAl Viro <viro@zeniv.linux.org.uk>2008-08-17 21:05:42 -0400
committerH. Peter Anvin <hpa@zytor.com>2008-10-22 22:55:20 -0700
commitbb8985586b7a906e116db835c64773b7a7d51663 (patch)
treede93ae58e88cc563d95cc124a73f3930594c6100 /arch/x86/include/asm/nops.h
parent8ede0bdb63305d3353efd97e9af6210afb05734e (diff)
x86, um: ... and asm-x86 move
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Diffstat (limited to 'arch/x86/include/asm/nops.h')
-rw-r--r--arch/x86/include/asm/nops.h118
1 files changed, 118 insertions, 0 deletions
diff --git a/arch/x86/include/asm/nops.h b/arch/x86/include/asm/nops.h
new file mode 100644
index 00000000000..ae742721ae7
--- /dev/null
+++ b/arch/x86/include/asm/nops.h
@@ -0,0 +1,118 @@
+#ifndef ASM_X86__NOPS_H
+#define ASM_X86__NOPS_H
+
+/* Define nops for use with alternative() */
+
+/* generic versions from gas
+ 1: nop
+ the following instructions are NOT nops in 64-bit mode,
+ for 64-bit mode use K8 or P6 nops instead
+ 2: movl %esi,%esi
+ 3: leal 0x00(%esi),%esi
+ 4: leal 0x00(,%esi,1),%esi
+ 6: leal 0x00000000(%esi),%esi
+ 7: leal 0x00000000(,%esi,1),%esi
+*/
+#define GENERIC_NOP1 ".byte 0x90\n"
+#define GENERIC_NOP2 ".byte 0x89,0xf6\n"
+#define GENERIC_NOP3 ".byte 0x8d,0x76,0x00\n"
+#define GENERIC_NOP4 ".byte 0x8d,0x74,0x26,0x00\n"
+#define GENERIC_NOP5 GENERIC_NOP1 GENERIC_NOP4
+#define GENERIC_NOP6 ".byte 0x8d,0xb6,0x00,0x00,0x00,0x00\n"
+#define GENERIC_NOP7 ".byte 0x8d,0xb4,0x26,0x00,0x00,0x00,0x00\n"
+#define GENERIC_NOP8 GENERIC_NOP1 GENERIC_NOP7
+
+/* Opteron 64bit nops
+ 1: nop
+ 2: osp nop
+ 3: osp osp nop
+ 4: osp osp osp nop
+*/
+#define K8_NOP1 GENERIC_NOP1
+#define K8_NOP2 ".byte 0x66,0x90\n"
+#define K8_NOP3 ".byte 0x66,0x66,0x90\n"
+#define K8_NOP4 ".byte 0x66,0x66,0x66,0x90\n"
+#define K8_NOP5 K8_NOP3 K8_NOP2
+#define K8_NOP6 K8_NOP3 K8_NOP3
+#define K8_NOP7 K8_NOP4 K8_NOP3
+#define K8_NOP8 K8_NOP4 K8_NOP4
+
+/* K7 nops
+ uses eax dependencies (arbitary choice)
+ 1: nop
+ 2: movl %eax,%eax
+ 3: leal (,%eax,1),%eax
+ 4: leal 0x00(,%eax,1),%eax
+ 6: leal 0x00000000(%eax),%eax
+ 7: leal 0x00000000(,%eax,1),%eax
+*/
+#define K7_NOP1 GENERIC_NOP1
+#define K7_NOP2 ".byte 0x8b,0xc0\n"
+#define K7_NOP3 ".byte 0x8d,0x04,0x20\n"
+#define K7_NOP4 ".byte 0x8d,0x44,0x20,0x00\n"
+#define K7_NOP5 K7_NOP4 ASM_NOP1
+#define K7_NOP6 ".byte 0x8d,0x80,0,0,0,0\n"
+#define K7_NOP7 ".byte 0x8D,0x04,0x05,0,0,0,0\n"
+#define K7_NOP8 K7_NOP7 ASM_NOP1
+
+/* P6 nops
+ uses eax dependencies (Intel-recommended choice)
+ 1: nop
+ 2: osp nop
+ 3: nopl (%eax)
+ 4: nopl 0x00(%eax)
+ 5: nopl 0x00(%eax,%eax,1)
+ 6: osp nopl 0x00(%eax,%eax,1)
+ 7: nopl 0x00000000(%eax)
+ 8: nopl 0x00000000(%eax,%eax,1)
+*/
+#define P6_NOP1 GENERIC_NOP1
+#define P6_NOP2 ".byte 0x66,0x90\n"
+#define P6_NOP3 ".byte 0x0f,0x1f,0x00\n"
+#define P6_NOP4 ".byte 0x0f,0x1f,0x40,0\n"
+#define P6_NOP5 ".byte 0x0f,0x1f,0x44,0x00,0\n"
+#define P6_NOP6 ".byte 0x66,0x0f,0x1f,0x44,0x00,0\n"
+#define P6_NOP7 ".byte 0x0f,0x1f,0x80,0,0,0,0\n"
+#define P6_NOP8 ".byte 0x0f,0x1f,0x84,0x00,0,0,0,0\n"
+
+#if defined(CONFIG_MK7)
+#define ASM_NOP1 K7_NOP1
+#define ASM_NOP2 K7_NOP2
+#define ASM_NOP3 K7_NOP3
+#define ASM_NOP4 K7_NOP4
+#define ASM_NOP5 K7_NOP5
+#define ASM_NOP6 K7_NOP6
+#define ASM_NOP7 K7_NOP7
+#define ASM_NOP8 K7_NOP8
+#elif defined(CONFIG_X86_P6_NOP)
+#define ASM_NOP1 P6_NOP1
+#define ASM_NOP2 P6_NOP2
+#define ASM_NOP3 P6_NOP3
+#define ASM_NOP4 P6_NOP4
+#define ASM_NOP5 P6_NOP5
+#define ASM_NOP6 P6_NOP6
+#define ASM_NOP7 P6_NOP7
+#define ASM_NOP8 P6_NOP8
+#elif defined(CONFIG_X86_64)
+#define ASM_NOP1 K8_NOP1
+#define ASM_NOP2 K8_NOP2
+#define ASM_NOP3 K8_NOP3
+#define ASM_NOP4 K8_NOP4
+#define ASM_NOP5 K8_NOP5
+#define ASM_NOP6 K8_NOP6
+#define ASM_NOP7 K8_NOP7
+#define ASM_NOP8 K8_NOP8
+#else
+#define ASM_NOP1 GENERIC_NOP1
+#define ASM_NOP2 GENERIC_NOP2
+#define ASM_NOP3 GENERIC_NOP3
+#define ASM_NOP4 GENERIC_NOP4
+#define ASM_NOP5 GENERIC_NOP5
+#define ASM_NOP6 GENERIC_NOP6
+#define ASM_NOP7 GENERIC_NOP7
+#define ASM_NOP8 GENERIC_NOP8
+#endif
+
+#define ASM_NOP_MAX 8
+
+#endif /* ASM_X86__NOPS_H */