From: Russell King Date: Sat, 16 Jul 2005 14:21:51 +0000 (+0100) Subject: [PATCH] ARM: Convert bitops to use ARMv6 ldrex/strex instructions X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=54ea06f6afe85aaf419e51343d4e4b5599197113;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git [PATCH] ARM: Convert bitops to use ARMv6 ldrex/strex instructions Signed-off-by: Russell King --- diff --git a/arch/arm/lib/bitops.h b/arch/arm/lib/bitops.h index 4a83ab6cd56..6976e60e47c 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