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

Marek Vasut
2012-07-04T00:14:37Z

Dear Ilya Yanok,

> Hi Tom,
>
> 04.07.2012 00:43, Tom Rini wrote:
> > On 07/03/2012 01:13 PM, Ilya Yanok wrote:
> >> Dear Marek,
> >>
> >> 30.06.2012 23:28, Marek Vasut wrote:
> >>>> Not exactly. It never worked (at least on my systems) with D-Cache
> >>>> enabled. But at least we had a choice of run-time disabled dcache.
> >>>> With the recent changes we have to disable cache support at compile
> >>>> time.
> >>>
> >>> I see what you're after. But do you consider runtime disabling the
> >>> cache is the
> >>> way to go or it's a way of hiding bugs?
> >>
> >> Both ;) And now we are going to hide even more bugs with compile-time
> >> disabling :(
> >
> > Does someone wish to argue we should disable USB support instead on
> > these platforms? I don't see anyone arguing "I have time to fix this
> > for v2012.07".
>
> I just looked at the code more carefully and it seems that most of the
> upper layers are in much better shape than I thought. So I think we
> should just extend your 2/6 patch to fix both address and size for
> structs QH and qtd and don't mess with buffer at all: if we got
> unaligned buffer -- it's definetely upper layer bug so we should produce
> some noise in this case. As I said upper layers seems to be in good
> shape so hopefully there won't be too much noise.
>
> Hm, probably we should put buffer invalidation under
> if(dcache_enabled()) to leave run-time cache disabling as rescue option
> for broken upper-layer code..
>
> I'm working on the patch now and hopefully will post it this night.

Ilya, thank you for saving my back ;-)

And thank you for investing your time into this.

> Regards, Ilya.

Best regards,
Marek Vasut