[U-Boot] [PATCH 2/2] mmc: tegra: invalidate complete cachelines

[Marek Vasut]

Dear Stephen Warren,

> On 11/02/2012 03:28 PM, Marek Vasut wrote:
> > Dear Stephen Warren,
> > 
> >> On 11/02/2012 02:38 PM, Marek Vasut wrote:
> ...
> 
> >>> Dumb question -- might be unrelated. Does the tegra mmc driver do DMA?
> >>> And if so, what happens if you do raw read to unaligned address (aka.
> >>> how come you don't need the bounce buffer)?
> >> 
> >> Yes, it does DMA, I believe. (At least if it doesn't, I have no idea why
> >> the driver is flushing caches!)
> >> 
> >> I guess we only support the use of aligned addresses, so e.g. the
> >> following would work:
> >> 
> >> ext2load mmc 0:1 0x00100000 /file
> >> 
> >> but the following wouldn't:
> >> 
> >> ext2load mmc 0:1 0x00100004 /file
> >> 
> >> which while I suppose it is an artificial restriction, hasn't been an
> >> issue in practice.
> > 
> > Then just enable the bounce buffer and it will work ;-)
> 
> You suggested that last time, and it made no difference then... In fact,
> the config option you mentioned isn't used anywhere in the srouce tree
> except adding bouncebuf.o

Bouncebuf.o ?

> into the build right now; which config option
> do you think I should use?

CONFIG_BOUNCE_BUFFER

It's used on mx28-based boards.

Best regards,
Marek Vasut