[U-Boot] [RFC/PATCH] davinci: disable dcache on boards with EMAC

[Ilya Yanok]

Hi Christian,

On 28.11.2011 19:43, Christian Riesch wrote:
>>> What do you mean by "broken"? Is it "never working" or is it "working
>>> sometimes" or "not working under specific conditions"? I have a DA850
>>> based board and I use the Davinci EMAC driver (CONFIG_DRIVER_TI_EMAC).
>>> I don't have these CONFIG_SYS_xCACHE_OFF defines in my board config
>>> file so I guess D-Cache is enabled. But Ethernet works fine, so what
>>> am I missing here? Is D-Cache disabled somewhere else?
>>
>> Today, right now?  I tried a dm365evm back in August on top-of-tree
>> and emac didn't work until I disabled caches.  I don't have day-to-day
>> access to that board however to confirm the current state.
> 
> Yes, right now.

I think it's because of:

commit cba4b1809f043bf85c806e5a4e342f62bd5ded45
Author: Aneesh V <aneesh at ti.com>
Date:   Tue Aug 16 04:33:05 2011 +0000

    arm: do not force d-cache enable on all boards

    c2dd0d45540397704de9b13287417d21049d34c6 added dcache_enable()
    to board_init_r(). This enables d-cache for all ARM boards.
    As a result some of the arm boards that are not cache-ready
    are broken. Revert this change and allow platform code to
    take the decision on d-cache enabling.

    Also add some documentation for cache usage in ARM.

    Signed-off-by: Aneesh V <aneesh at ti.com>

Don't you see "WARNING: Caches not enabled" message during boot?

2Wolfgang: So caches are actually disabled on everything except OMAP...

Regards, Ilya.