[U-Boot] [PATCH v4 3/6] mcx: Disable DCACHE since USB EHCI is enabled

Tom Rini
2012-06-28T17:29:34Z

On 06/28/2012 07:37 AM, Marek Vasut wrote:
> Dear Ilya Yanok,
>
>> Dear Marek,
>>
>> 28.06.2012 02:48, Marek Vasut wrote:
>>>> Sorry for missing this discussion. I think compile-time disabling of the
>>>> cache is too brutal.
>>>> ehci-hcd cache handling is broken anyway: doing unaligned
>>>> flushes/invalidates is a bug, and we know for sure that upper layers
>>>> don't care about alignment (and I bet ehci-hcd does this even for its
>>>> internal buffers). So what's the point in all this cache handling in
>>>> ehci-hcd? It's not going to work anyway and just produces problems. So I
>>>> suggest to just disable all this stuff until generic code will be fixed.
>>>> Alternatively we can do bounce-buffering inside driver.
>>>
>>> We should rather introduce generic bounce buffer. But the upper layers
>>> are getting fixed recently so we should be getting there.
>>
>> Really? Don't forget my old patch [1] then ;)
>> Still I think we should rip off all the cache stuff from ehci-hcd until
>> all patches for upper layers are included. Again, this stuff doesn't do
>> proper things now anyway and USB won't work with dcache enabled.
>
> Have you tested? I enabled dcache on m28 and tried asix ethernet (needed a
> patch) and loading from ext2 and vfat (worked).

So then we have more places that accidentially aligned to 32bytes since
this does not work on TI parts which require 64byte alignment.

--
Tom