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

Tom Rini
2012-01-20T11:56:48Z

On Fri, Jan 20, 2012 at 12:28 AM, Christian Riesch
<christian.riesch@omicron.at> 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?

I'm away from the code atm (and when I get back I can point Aneesh at
it as well), but DCACHE is never enabled and I'm thinking ICACHE too.

--
Tom