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 _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
