ARM: FIX for dcache_disable() for ARM926ej-s
PATCH 1/1 ARM: FIX for dcache_disable() for ARM926ej-s
the cache also needs to be invalidated, not just flushed, Since re-enabling it, can cause inconsistent data without invalidation.
--- arch/arm/lib/cache.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
arch/arm/lib/cache.c +2 -0
@@ -37,6 +37,8 @@ void __flush_cache(unsigned long start, unsigned long size) asm("0: mrc p15, 0, r15, c7, c10, 3\n\t" "bne 0b\n" : : :"memory" );/* disable write buffer as well (page 2-22) */ asm("mcr p15, 0, %0, c7, c10, 4" : :"r" (0 )); +/* Invalidate dcache as well */ + asm("mcr p15, 0, %0, c7, c6, 0" : :"r" (0 ));#endif return ; }
Signature · 1 line
1.7.0.4
PATCH 1/1 ARM: FIX for dcache_disable() for ARM926ej-s
Hi Bas,
Le 04/11/2011 10:40, Bas van den Berg a ?crit :
Quoted 13 lines
the cache also needs to be invalidated, not just flushed, Since re-enabling it, can cause inconsistent data without invalidation.
Signed-off-by Bas van den Berg<[email protected]>--- arch/arm/lib/cache.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)arch/arm/lib/cache.c +0
-0
arch/arm/lib/cache.c void __flush_cache(unsigned long start, unsigned long size) · line 44
Quoted 8 lines
arch/arm/lib/cache.c +2
-0@@ -37,6 +37,8 @@ void __flush_cache(unsigned long start, unsigned long size) asm("0: mrc p15, 0, r15, c7, c10, 3\n\t" "bne 0b\n" : : :"memory" );/* disable write buffer as well (page 2-22) */ asm("mcr p15, 0, %0, c7, c10, 4" : :"r" (0 )); +/* Invalidate dcache as well */ + asm("mcr p15, 0, %0, c7, c6, 0" : :"r" (0 ));#endif return ; }
Come to think of it... NAK, sorry. Flushing should do what it says on the tin, and invalidating is not what it says -- especially considering your intent is not about flushing but about disabling ('re-enabling...')
If you need the cache to be flushed then invalidated then disabled, then call all three functions where you need that, i.e. find the place where there is only a call to __flush_cache() and append a call to __invalidate_cache(), and if that happens a lot, then feel free to provide a new function that will sequence flush and invalidate.
Amicalement,
Signature · 1 line
Albert.