On Fri, Oct 19, 2012 at 10:26:20AM +0000, Bedia, Vaibhav wrote:

Hi Matt,

On Thu, Oct 18, 2012 at 18:56:39, Porter, Matt wrote:

quoted

Changes since v2:
	- Rebased on 3.7-rc1
	- Fixed bug in DT/pdata parsing first found by Gururaja
	  that turned out to be masked by some toolchains
	- Dropped unused mach-omap2/devices.c hsmmc patch
	- Added AM33XX crossbar DMA event mux support
	- Added am335x-evm support

Changes since v1:
	- Rebased on top of mainline from 12250d8
	- Dropped the feature removal schedule patch
	- Implemented dma_request_slave_channel_compat() and
	  converted the mmc and spi drivers to use it
	- Dropped unneeded #address-cells and #size-cells from
	  EDMA DT support
	- Moved private EDMA header to linux/platform_data/ and
	  removed some unneeded definitions
	- Fixed parsing of optional properties

TODO:
	- Add dmaengine support for per-channel caps so the
	  hack to set the maximum segments can be replaced with
	  a query to the dmaengine driver

This series adds DMA Engine support for AM33xx, which uses
an EDMA DMAC. The EDMA DMAC has been previously supported by only
a private API implementation (much like the situation with OMAP
DMA) found on the DaVinci family of SoCs.

The series applies on top of 3.7-rc1 and the following patches:

	- GPMC fails to reserve memory fix:
	  http://www.spinics.net/lists/linux-omap/msg79675.html
	- TPS65910 regulator fix:
	  https://patchwork.kernel.org/patch/1593651/
	- dmaengine DT support from Vinod's dmaengine_dt branch in
	  git://git.infradead.org/users/vkoul/slave-dma.git since
	  027478851791df751176398be02a3b1c5f6aa824

The approach taken is similar to how OMAP DMA is being converted to
DMA Engine support. With the functional EDMA private API already
existing in mach-davinci/dma.c, we first move that to an ARM common
area so it can be shared. Adding DT and runtime PM support to the
private EDMA API implementation allows it to run on AM33xx. AM33xx
*only* boots using DT so we leverage Jon's generic DT DMA helpers to
register EDMA DMAC with the of_dma framework and then add support
for calling the dma_request_slave_channel() API to both the mmc
and spi drivers.

With this series both BeagleBone and the AM335x EVM have working
MMC and SPI support.

This is tested on BeagleBone with a SPI framebuffer driver and MMC
rootfs. A trivial gpio DMA event misc driver was used to test the
crossbar DMA event support. It is also tested on the AM335x EVM
with the onboard SPI flash and MMC rootfs. The branch at
https://github.com/ohporter/linux/tree/edma-dmaengine-v3 has the
complete series, dependencies, and some test drivers/defconfigs.

I didn't see all the patches that you posted on edma-dmaengine-v3
but I do seem them on edma-dmaengine-am33xx-v3 branch.

I see I referenced the wrong branch in the cover letter. Thanks for
testing and noticing this. Sorry to make you hunt for the correct
branch in that repo. ;) 

https://github.com/ohporter/linux/tree/edma-dmaengine-am33xx-v3
is indeed the correct branch for those wanting to pull this in or
grab some of the not-to-be-merged drivers I used for testing.

I added a couple of patches to enable earlyprintk and build the DTB
appended kernel image uImage-dtb.am335x-evm

Here's what i see

[...]

<snip>

[    0.175354] edma: probe of 49000000.edma failed with error -16

I missed an uninitialized pdata case in the bug fixes mentioned in
the changelog and the folks previously failing the same way didn't
hit the case I suspect you are hitting. Can you try this and let me
know how it works?

Thanks,
Matt

diff --git a/arch/arm/common/edma.c b/arch/arm/common/edma.c
index b761b7a..b43b327 100644
--- a/arch/arm/common/edma.c
+++ b/arch/arm/common/edma.c

@@ -1619,7 +1619,7 @@ static int __init edma_probe(struct platform_device *pdev)
 
 	if (node) {
 		pdata = devm_kzalloc(dev,
-				     sizeof(struct edma_soc_info),
+				     EDMA_MAX_CC*sizeof(struct edma_soc_info),
 				     GFP_KERNEL);
 		edma_of_parse_dt(dev, node, pdata);
 		info = &pdata;