[PATCH] ARM: Convert bitops to use ARMv6 ldrex/strex instructions
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h
index 4a83ab6..6976e60e 100644
--- a/arch/arm/lib/bitops.h
+++ b/arch/arm/lib/bitops.h
@@ -1,3 +1,33 @@
+#if __LINUX_ARM_ARCH__ >= 6
+ .macro bitop, instr
+ mov r2, #1
+ and r3, r0, #7 @ Get bit offset
+ add r1, r1, r0, lsr #3 @ Get byte offset
+ mov r3, r2, lsl r3
+1: ldrexb r2, [r1]
+ \instr r2, r2, r3
+ strexb r0, r2, [r1]
+ cmpne r0, #0
+ bne 1b
+ mov pc, lr
+ .endm
+
+ .macro testop, instr, store
+ and r3, r0, #7 @ Get bit offset
+ mov r2, #1
+ add r1, r1, r0, lsr #3 @ Get byte offset
+ mov r3, r2, lsl r3 @ create mask
+1: ldrexb r2, [r1]
+ ands r0, r2, r3 @ save old value of bit
+ \instr ip, r2, r3 @ toggle bit
+ strexb r2, ip, [r1]
+ cmp r2, #0
+ bne 1b
+ cmp r0, #0
+ movne r0, #1
+2: mov pc, lr
+ .endm
+#else
.macro bitop, instr
and r2, r0, #7
mov r3, #1
@@ -31,3 +61,4 @@
moveq r0, #0
mov pc, lr
.endm
+#endif