Hi,
On Saturday 01 December 2012 04:31 AM, Simon Glass wrote:
From: Arun Mankuzhi arun.m@samsung.com
In Cortex-A15 architecture, when we run cache invalidate the cache clean operation executes automatically. So if there are any dirty cache lines before disabling the L2 cache these will be synchronized with the main memory when invalidate_dcache_all() runs in the last part of U-boot
The two functions after flush_dcache_all is using the stack. So this data will be on the cache. After disable when invalidate is called the data will be flushed from cache to memory. This corrupts the stack in invalida_dcache_all. So this change is required to avoid the u-boot hang.
So flush has to be done just before clearing CR_C bit
Signed-off-by: Arun Mankuzhi arun.m@samsung.com Signed-off-by: Simon Glass sjg@chromium.org
Changes in v2: None
arch/arm/lib/cache-cp15.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-)
diff --git a/arch/arm/lib/cache-cp15.c b/arch/arm/lib/cache-cp15.c index 939de10..06119c8 100644 --- a/arch/arm/lib/cache-cp15.c +++ b/arch/arm/lib/cache-cp15.c @@ -124,8 +124,11 @@ static void cache_disable(uint32_t cache_bit) return; /* if disabling data cache, disable mmu too */ cache_bit |= CR_M;
flush_dcache_all();
- reg = get_cr();
- cp_delay();
- if (cache_bit == (CR_C | CR_M))
flush_dcache_all();
Sorry for the late question. But are the two functions that is after flush_dcache_all currently ?
There is only set_cr, which does not use the stack.
Regards, Sricharan