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| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-03 11:15:53 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-04-14 22:26:51 +0100 |
| commit | 47b8484ea6569511a3cd915bea29886b4cd08333 (patch) | |
| tree | c4f80e72ea340c972fcf55cf13b7c27d223bc31b /arch/arm/mm | |
| parent | 5aca370826a2487aaaae5db31f6bb0b906e9755f (diff) | |
| download | linux-47b8484ea6569511a3cd915bea29886b4cd08333.tar.bz2 | |
ARM: cache-v7: shift CLIDR to extract appropriate field before masking
Rather than have code which masks and then shifts, such as:
mrc p15, 1, r0, c0, c0, 1
ALT_SMP(ands r3, r0, #7 << 21)
ALT_UP( ands r3, r0, #7 << 27)
ALT_SMP(mov r3, r3, lsr #20)
ALT_UP( mov r3, r3, lsr #26)
re-arrange this as a shift and then mask. The masking is the same for
each field which we want to extract, so this allows the mask to be
shared amongst code paths:
mrc p15, 1, r0, c0, c0, 1
ALT_SMP(mov r3, r0, lsr #20)
ALT_UP( mov r3, r0, lsr #26)
ands r3, r3, #7 << 1
Use this method for the LoUIS, LoUU and LoC fields.
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm/mm')
| -rw-r--r-- | arch/arm/mm/cache-v7.S | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S index 30c81e7d6aaa..d062f8cbb886 100644 --- a/arch/arm/mm/cache-v7.S +++ b/arch/arm/mm/cache-v7.S @@ -90,8 +90,9 @@ ENDPROC(v7_flush_icache_all) ENTRY(v7_flush_dcache_louis) dmb @ ensure ordering with previous memory accesses mrc p15, 1, r0, c0, c0, 1 @ read clidr, r0 = clidr - ALT_SMP(ands r3, r0, #(7 << 21)) @ extract LoUIS from clidr - ALT_UP(ands r3, r0, #(7 << 27)) @ extract LoUU from clidr +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 #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 @@ -99,10 +100,8 @@ ENTRY(v7_flush_dcache_louis) movteq r1, #:upper16:0x410fc090 biceq r2, r2, #0x0000000f @ clear minor revision number teqeq r2, r1 @ test for errata affected core and if so... - orreqs r3, #(1 << 21) @ fix LoUIS value (and set flags state to 'ne') + moveqs r3, #1 << 1 @ fix LoUIS value (and set flags state to 'ne') #endif - ALT_SMP(mov r3, r3, lsr #20) @ r3 = LoUIS * 2 - ALT_UP(mov r3, r3, lsr #26) @ r3 = LoUU * 2 reteq lr @ return if level == 0 mov r10, #0 @ r10 (starting level) = 0 b flush_levels @ start flushing cache levels @@ -120,8 +119,8 @@ ENDPROC(v7_flush_dcache_louis) ENTRY(v7_flush_dcache_all) dmb @ ensure ordering with previous memory accesses mrc p15, 1, r0, c0, c0, 1 @ read clidr - ands r3, r0, #0x7000000 @ extract loc from clidr - mov r3, r3, lsr #23 @ left align loc bit field + mov r3, r0, lsr #23 @ move LoC into position + ands r3, r3, #7 << 1 @ extract LoC*2 from clidr beq finished @ if loc is 0, then no need to clean mov r10, #0 @ start clean at cache level 0 flush_levels: |