On Wed, 4 Mar 2009 20:47:44 +0300 Anton Vorontsov <avoront...@ru.mvista.com> wrote:
> > I'll get rid of this particular patch, and put some BLOCK_SIZE > magic into the writew accessor (to clean the DMA bits) instead. > > Though, I'll prepare another patch to force blksz to 2048, since > eSDHC specifies "3" in the blksz capability bitfield, and that > causes SDHCI core to fall back to the 512 byte blocks. > Ok. > > After all, is it ever used? > > Not sure, maybe `dd bs=' can use it? A bit lazy to check this > right now, but from the quick tests, enabling/disabling "blksz > of 4096 bytes" doesn't cause any performance change. At least > with the ordinary SD cards. > Memory cards will not use this (at least not with the current standards), as the block layer thinks in 512 byte blocks. Also, the sector size propagates to user space in a way that causes filesystems to behave differently, making cards incompatible with all other operating systems (i.e. if we don't use 512 byte blocks). So the only scenario where this might be used is SDIO, and I'm not sure such big blocks are a win there either because of the overhead of changing block size. Rgds -- -- Pierre Ossman WARNING: This correspondence is being monitored by the Swedish government. Make sure your server uses encryption for SMTP traffic and consider using PGP for end-to-end encryption.
signature.asc
Description: PGP signature
_______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev