[PATCH v3 0/3] DaVinci DMA engine conversion

Hi Matt,

On 27.08.2012 17:33, Daniel Mack wrote:

On 23.08.2012 03:09, Matt Porter wrote:

quoted

This series begins the conversion of the DaVinci private EDMA API
implementation to a DMA engine driver and converts two of the three
in-kernel users of the private EDMA API to DMA engine.

The approach taken is similar to the recent OMAP DMA Engine
conversion. The EDMA DMA Engine driver is a wrapper around the existing
private EDMA implementation and registers the platform device within
the driver.  This allows the conversion series to stand alone with just
the drivers and no changes to platform code. It also allows peripheral
drivers to continue to use the private EDMA implementation until they
are converted.

The EDMA DMA Engine driver supports slave transfers only at this time. It
is planned to add cyclic transfers in support of audio peripherals.

There are three users of the private EDMA API in the kernel now:
davinci_mmc, spi-davinci, and davinci-mcasp.  This series provides DMA
Engine conversions for the davinci_mmc and spi-davinci drivers which
use the supported slave transfers.

This series has been tested on an AM18x EVM and Hawkboard with
driver performance comparable to that of the private EDMA API
implementations. Both MMC0 and MMC1 are tested which handles the
DA850/OMAP-L138/AM18x specific case where MMC1 uses DMA channels on
a second EDMA channel controller.  All other platforms have a simpler
design with just a single EDMA channel controller.

For those wanting to easily test this series, I've pushed a branch for
each version to my github tree at https://github.com/ohporter/linux. The
current branch is edma-dmaengine-v3.

After this series, the current plan is to complete the mcasp driver
conversion which includes adding cyclic dma support. This will then
enable the removal and refactoring of the private EDMA API functionality
into the EDMA DMA Engine driver.  Since EDMA is also used on the AM33xx
family of parts in mach-omap2/, the plan is to enable this driver on
that platform as well.

Once you have a patch for the McASP driver conversion, I can happily
test this on a AM33xx board, together with Gururaja's latest McASP
refactoring series. Let me know how I can help you here.

Did you find some time yet to continue on this side? I don't want to
appear pushy, but as I need to finish some DT transition on a
AM33xx-based board, I would much like to help out here, in case I can do
anything to help speed things along.


Many thanks for your work!

Daniel