From: Russell King Date: Fri, 3 Apr 2015 10:32:34 +0000 (+0100) Subject: ARM: cache-v7: optimise test for Cortex A9 r0pX devices X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=aaf4b5d92ce8299a363f1c0d7dc00aafde532e56;p=linux-beck.git ARM: cache-v7: optimise test for Cortex A9 r0pX devices Eliminate one unnecessary instruction from this test by pre-shifting the Cortex A9 ID - we can shift the actual ID in the teq instruction thereby losing the pX bit of the ID at no cost. Reviewed-by: Catalin Marinas Signed-off-by: Russell King --- diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S index 793d061b4dce..a134d8a13d00 100644 --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S @@ -97,10 +97,9 @@ ALT_UP( mov r3, r0, lsr #26) @ move LoUU into position #ifdef CONFIG_ARM_ERRATA_643719 ALT_SMP(mrc p15, 0, r2, c0, c0, 0) @ read main ID register ALT_UP( ret lr) @ LoUU is zero, so nothing to do - movw r1, #:lower16:0x410fc090 @ ID of ARM Cortex A9 r0p? - movt r1, #:upper16:0x410fc090 - bic r2, r2, #0x0000000f @ clear minor revision number - teq r2, r1 @ test for errata affected core and if so... + movw r1, #:lower16:(0x410fc090 >> 4) @ ID of ARM Cortex A9 r0p? + movt r1, #:upper16:(0x410fc090 >> 4) + teq r1, r2, lsr #4 @ test for errata affected core and if so... moveq r3, #1 << 1 @ fix LoUIS value beq start_flush_levels @ start flushing cache levels #endif