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authorCatalin Marinas <catalin.marinas@arm.com>2010-12-07 16:56:29 +0100
committerRussell King <rmk+kernel@arm.linux.org.uk>2010-12-12 23:25:58 +0000
commitda30e0ac0f9a521f0cfec8145ddd1ad131f66d61 (patch)
tree4a9002e6fca4d4763b40908403fc177153b9a6a8 /arch/arm
parentf91e2c3bd427239c198351f44814dd39db91afe0 (diff)
downloadlinux-da30e0ac0f9a521f0cfec8145ddd1ad131f66d61.tar.bz2
ARM: 6528/1: Use CTR for the I-cache line size on ARMv7
The current implementation of the v7_coherent_*_range function assumes that the D and I cache lines have the same size, which is incorrect architecturally. This patch adds the icache_line_size macro which reads the CTR register. The main loop in v7_coherent_*_range is split in two independent loops or the D and I caches. This also has the performance advantage that the DSB is moved outside the main loop. Reported-by: Kevin Sapp <ksapp@quicinc.com> Signed-off-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.S27
-rw-r--r--arch/arm/mm/proc-macros.S10
2 files changed, 27 insertions, 10 deletions
diff --git a/arch/arm/mm/cache-v7.S b/arch/arm/mm/cache-v7.S
index a3ebf7a4f49b..6136e68ce953 100644
--- a/arch/arm/mm/cache-v7.S
+++ b/arch/arm/mm/cache-v7.S
@@ -173,15 +173,22 @@ ENTRY(v7_coherent_user_range)
UNWIND(.fnstart )
dcache_line_size r2, r3
sub r3, r2, #1
- bic r0, r0, r3
+ bic r12, r0, r3
1:
- USER( mcr p15, 0, r0, c7, c11, 1 ) @ clean D line to the point of unification
+ USER( mcr p15, 0, r12, c7, c11, 1 ) @ clean D line to the point of unification
+ add r12, r12, r2
+ cmp r12, r1
+ blo 1b
dsb
- USER( mcr p15, 0, r0, c7, c5, 1 ) @ invalidate I line
- add r0, r0, r2
+ icache_line_size r2, r3
+ sub r3, r2, #1
+ bic r12, r0, r3
2:
- cmp r0, r1
- blo 1b
+ USER( mcr p15, 0, r12, c7, c5, 1 ) @ invalidate I line
+ add r12, r12, r2
+ cmp r12, r1
+ blo 2b
+3:
mov r0, #0
ALT_SMP(mcr p15, 0, r0, c7, c1, 6) @ invalidate BTB Inner Shareable
ALT_UP(mcr p15, 0, r0, c7, c5, 6) @ invalidate BTB
@@ -194,10 +201,10 @@ ENTRY(v7_coherent_user_range)
* isn't mapped, just try the next page.
*/
9001:
- mov r0, r0, lsr #12
- mov r0, r0, lsl #12
- add r0, r0, #4096
- b 2b
+ mov r12, r12, lsr #12
+ mov r12, r12, lsl #12
+ add r12, r12, #4096
+ b 3b
UNWIND(.fnend )
ENDPROC(v7_coherent_kern_range)
ENDPROC(v7_coherent_user_range)
diff --git a/arch/arm/mm/proc-macros.S b/arch/arm/mm/proc-macros.S
index 321555b894d1..b795afd0a2c6 100644
--- a/arch/arm/mm/proc-macros.S
+++ b/arch/arm/mm/proc-macros.S
@@ -72,6 +72,16 @@
mov \reg, \reg, lsl \tmp @ actual cache line size
.endm
+/*
+ * icache_line_size - get the minimum I-cache line size from the CTR register
+ * on ARMv7.
+ */
+ .macro icache_line_size, reg, tmp
+ mrc p15, 0, \tmp, c0, c0, 1 @ read ctr
+ and \tmp, \tmp, #0xf @ cache line size encoding
+ mov \reg, #4 @ bytes per word
+ mov \reg, \reg, lsl \tmp @ actual cache line size
+ .endm
/*
* Sanity check the PTE configuration for the code below - which makes