pxamci: fix byte aligned DMA transfers
authorPhilipp Zabel <philipp.zabel@gmail.com>
Sat, 5 Jul 2008 23:15:34 +0000 (01:15 +0200)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 24 Jul 2008 16:14:10 +0000 (09:14 -0700)
commit708cc88d265a25f51dec199caa89aaee60967b3b
tree1c26cb5f1c07564d128fd31715623c4add9993a4
parent0a96934becd9759b4dbf247226557c22abd12824
pxamci: fix byte aligned DMA transfers

commit 97f8571e663c808ad2d01a396627235167291556 upstream

The pxa27x DMA controller defaults to 64-bit alignment. This caused
the SCR reads to fail (and, depending on card type, error out) when
card->raw_scr was not aligned on a 8-byte boundary.

For performance reasons all scatter-gather addresses passed to
pxamci_request should be aligned on 8-byte boundaries, but if
this can't be guaranteed, byte aligned DMA transfers in the
have to be enabled in the controller to get correct behaviour.

Signed-off-by: Philipp Zabel <philipp.zabel@gmail.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
drivers/mmc/host/pxamci.c