pxamci: fix byte aligned DMA transfers
authorPhilipp Zabel <philipp.zabel@gmail.com>
Sat, 5 Jul 2008 23:15:34 +0000 (01:15 +0200)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sun, 6 Jul 2008 17:37:40 +0000 (10:37 -0700)
commit97f8571e663c808ad2d01a396627235167291556
tree2e189714b2355996dba8974642460580077d3c0e
parent09ca8adbe9f724a7e96f512c0039c4c4a1c5dcc0
pxamci: fix byte aligned DMA transfers

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>
drivers/mmc/host/pxamci.c