[U-Boot] [PATCH] 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.
Signed-off-by: Bas van den Berg b.van.den.berg.nl@gmail.com --- arch/arm/lib/cache.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c index b545fb7..10eb8c9 100644 --- a/arch/arm/lib/cache.c +++ b/arch/arm/lib/cache.c @@ -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; }

Hi Bas,
Le 04/11/2011 10:40, Bas van den Berg a écrit :
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 Bergb.van.den.berg.nl@gmail.com
arch/arm/lib/cache.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/arch/arm/lib/cache.c b/arch/arm/lib/cache.c index b545fb7..10eb8c9 100644 --- a/arch/arm/lib/cache.c +++ b/arch/arm/lib/cache.c @@ -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,
participants (2)
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Albert ARIBAUD
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Bas van den Berg