Commit Graph

3 Commits

Author SHA1 Message Date
Stephen Warren 84d35b2863 common: rework bouncebuf implementation
The current bouncebuf API requires all parameters to be passed to both
bounce_buffer_start() and bounce_buffer_stop(). Modify the bouncebuf
start function to accept a state structure as a parameter, and only
require that state struct to be passed to the stop function. This
simplifies usage of the bounce buffer by clients.

Don't modify the data pointer, but rather store the temporary buffer in
this state struct. The bouncebuf code ensures that client code can
always use a single buffer pointer in the state structure, irrespective
of whether a bounce buffer actually had to be allocated.

Move cache management logic into the bounce buffer code, so that each
client doesn't have to duplicate this. I believe there's no need to
invalidate the buffer before a DMA operation, since flushing the cache
should prevent any write-backs.

Update the MXS MMC driver for this change.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Andy Fleming <afleming@freescale.com>
2012-11-27 17:26:48 -06:00
Stephen Warren 4ea7a09faf bouncebuf: remove dummy implementation
If any driver ever needs to use the bounce buffer API, it always needs
to use it. As such, providing a dummy implementation of those APIs when
CONFIG_BOUNCE_BUFFER isn't defined does not make sense. Remove the dummy
implementation.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Simon Glass <sjg@chromium.org>
Tested-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Andy Fleming <afleming@freescale.com>
2012-11-27 17:26:48 -06:00
Marek Vasut b660df3c90 COMMON: Implement common bounce buffer
Implement common bounce buffer to be used on a less capable hardware.
That includes hardware that can not do DMA from any address or such.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Andy Fleming <afleming@freescale.com>
Signed-off-by: Andy Fleming <afleming@freescale.com>
2012-10-22 02:53:35 -05:00