[U-Boot] [PATCH 1/2 V2] arm926: Flush the data cache before disabling it.

Aneesh V
2012-01-20T08:52:24Z

Sughosh,

On Friday 20 January 2012 12:58 PM, Christian Riesch wrote:
> On Thu, Jan 19, 2012 at 12:54 PM, Aneesh V<aneesh@ti.com> wrote:
>> On Thursday 19 January 2012 05:00 PM, Christian Riesch wrote:
>>> On Thu, Jan 19, 2012 at 11:17 AM, Aneesh V<aneesh@ti.com> wrote:
>>>> On Thursday 19 January 2012 12:23 PM, Sughosh Ganu wrote:
>>>>> Tried a few things on my end.
>>>>> * Read the D-cache value in the spl, and confirmed that the data
>>>>> cache is indeed not enabled.
>>>>
>>>> What is the value of the B bit in CP15 SCR register? I wonder if RBL is
>>>> doing all the IMB operations required after copying the SPL image and
>>>> before executing it. IMB is required for consistency between data and
>>>> instruction sides.
>>>
>>> Only if caches are used, right? Or also without caches?
>>> Tom wrote that RBL does not turn on cache.
>>> Regards, Christian
>>
>> Only D-cache seems to be disabled in this case. I-cache and Write
>> buffer are likely to be enabled. If so, all the IMB operations except
>> the data-cache flushing are still relevant.
>
> Tom, when you wrote that RBL does not turn on caches, did you mean it
> never turns it on or it turns some of them on and turns them off
> before exit?
> Christian

Can you send the value of SCR you found at SPL entry? This will clarify
what's enabled and what's not.