diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-03 11:25:39 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-14 22:26:52 +0100 |
| commit | d3cd451dfb579367b4c5968256b3d8342dd0b0e8 (patch) | |
| tree | fa411df2beabfe0378906882f026c03560ea1b97 /arch/arm | |
| parent | cd8b24d9e852b53e68c69a086358c81423dfb8d1 (diff) | |
ARM: cache-v7: optimise branches in v7_flush_cache_louis
Optimise the branches such that for the majority of unaffected devices,
we avoid needing to execute the errata work-around code path by
branching to start_flush_levels early.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
| -rw-r--r-- | arch/arm/mm/cache-v7.S | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S index 5b5d0c00bca7..793d061b4dce 100644 --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S @@ -93,17 +93,18 @@ ENTRY(v7_flush_dcache_louis) ALT_SMP(mov r3, r0, lsr #20) @ move LoUIS into position ALT_UP( mov r3, r0, lsr #26) @ move LoUU into position ands r3, r3, #7 << 1 @ extract LoU*2 field from clidr + bne start_flush_levels @ LoU != 0, start flushing #ifdef CONFIG_ARM_ERRATA_643719 - ALT_SMP(mrceq p15, 0, r2, c0, c0, 0) @ read main ID register - ALT_UP(reteq lr) @ LoUU is zero, so nothing to do - movweq r1, #:lower16:0x410fc090 @ ID of ARM Cortex A9 r0p? - movteq r1, #:upper16:0x410fc090 - biceq r2, r2, #0x0000000f @ clear minor revision number - teqeq r2, r1 @ test for errata affected core and if so... - moveqs r3, #1 << 1 @ fix LoUIS value (and set flags state to 'ne') +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... + moveq r3, #1 << 1 @ fix LoUIS value + beq start_flush_levels @ start flushing cache levels #endif - reteq lr @ return if level == 0 - b start_flush_levels @ start flushing cache levels + ret lr ENDPROC(v7_flush_dcache_louis) /* |