[PATCH] Implements DMA on mmci driver for LPC3250 plateform

Roland Stigge stigge at antcom.de
Wed Jan 23 06:36:36 EST 2013

On 01/23/2013 11:11 AM, Gabriele Mondada wrote:
> Signed-off-by: Gabriele Mondada <gabriele at precidata.com>
> UPDATE: Here is the patch cleaned up and validated with scripts/checkpatch.pl. I also add a check to prevent crashing when DMA is disabled.
> Hi,
> Currently, LPC32xx plateform do not enable DMA on the mmci driver. This makes the driver useless because getting out data from a 64 bytes FIFO by interrupt is not fast enough (at standard SD-card data rate).
> DMA is not enabled because LPC32xx has a bug that prevent DMA to work properly with the MMC controller (silicon bug, I guess). NXP did a patch to workaround this, but it has not been commited on the main branch. The patch is for linux and does not use dmaengine.
> So, I reworked this patch to make it compatible with the last kernel (3.7). Here it is. Have I any chance to see this patch be commited on the main branch?
> Thanks a lot,
> Gabriele 

Please consider that when I got this mail, the source/patch formatting
was broken, like this:

drivers/dma/amba-pl08x.c |   20 ++++++
drivers/mmc/host/mmci.c  |  159 =
drivers/mmc/host/mmci.h  |   12 +++-
3 files changed, 174 insertions(+), 17 deletions(-)

diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index d1cc579..728f65f 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -1758,6 +1758,26 @@ static void pl08x_free_virtual_channels(struct =
dma_device *dmadev)

Please use "git send-email" or sth. where code is included unchanged.



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