[U-Boot] [PATCH 2/4] cache_v7: Check for dcache enablement in dcache flush functions

[Tom Rini]

On 06/14/2012 10:48 PM, R, Sricharan wrote:
> Hi Tom,
> 
> On Fri, Jun 15, 2012 at 12:31 AM, Tom Rini <trini at ti.com> wrote:
>> If we are built with D-CACHE enabled but have run 'dcache off' and then
>> attempt to flush unaligned regions we spam the console with problems
>> that aren't true (as the cache was off).
>>
>   Today we do cache maintenance operations after the dcache is turned off.
>   One example is before jumping to kernel, we try to invalidate the caches,
>   in cache turned off state. So with this patch those maintenance calls will
>   do nothing, which is not correct.

Ah yes,  But, shouldn't we be doing these same operations as part of
turning the cache off?

>    If it is a problem with unaligned regions, then that is the only
> thing to be fixed
>   right ?. Just trying to understand why this change is required ?

The problem is that within the USB/network/filesystem stacks we have a
lot of not cache safe alignments apparently.  Without this every '#' of
a tftp gives a screen full of error printfs.  So tftp'ing a kernel takes
minutes, not seconds, to complete.

-- 
Tom