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[PATCH] ARM: Convert bitops to use ARMv6 ldrex/strex instructions 

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
This commit is contained in:
Russell King 2005-07-16 15:21:51 +01:00 committed by Russell King
parent 9fb1759a31
commit 54ea06f6af
1 changed files with 31 additions and 0 deletions
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31
arch/arm/lib/bitops.h
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@ -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