[PATCH v2 0/4] dma: Add Xilinx ZynqMP DPDMA driver

Laurent Pinchart
2019-11-07T02:14:17Z

Hello,

This patch series adds a new driver for the DPDMA engine found in the
Xilinx ZynqMP. It is based on the version posted by Hyun in [1] and [2].
I have rebased the driver on top of v5.4-rc6, incorporated most review
comments, and successfully tested the result with the ZynqMP DisplayPort
subsystem DRM driver.

There is one review comment that is still pending: switching to
virt-dma. I started investigating this, and it quickly appeared that
this would result in an almost complete rewrite of the driver's logic.
While the end result may be better, I wonder if this is worth it, given
that the DPDMA is tied to the DisplayPort subsystem and can't be used
with other DMA slaves. The DPDMA is thus used with very specific usage
patterns, which don't need the genericity of descriptor handling
provided by virt-dma. Vinod, what's your opinion on this ? Is virt-dma
usage a blocker to merge this driver, could we switch to it later, or is
it just overkill in this case ?

[1] https://lore.kernel.org/dmaengine/1515204848-3493-1-git-send-email-hyun.kwon@xilinx.com/
[2] https://lore.kernel.org/dmaengine/1515204848-3493-2-git-send-email-hyun.kwon@xilinx.com/

Hyun Kwon (1):
dma: xilinx: dpdma: Add the Xilinx DisplayPort DMA engine driver

Laurent Pinchart (3):
dt: bindings: dma: xilinx: dpdma: DT bindings for Xilinx DPDMA
dma: xilinx: dpdma: Add debugfs support
arm64: dts: zynqmp: Add DPDMA node

.../dma/xilinx/xlnx,zynqmp-dpdma.yaml | 68 +
MAINTAINERS | 9 +
arch/arm64/boot/dts/xilinx/zynqmp-clk.dtsi | 4 +
arch/arm64/boot/dts/xilinx/zynqmp.dtsi | 10 +
drivers/dma/Kconfig | 9 +
drivers/dma/xilinx/Makefile | 1 +
drivers/dma/xilinx/xilinx_dpdma.c | 2304 +++++++++++++++++
include/dt-bindings/dma/xlnx-zynqmp-dpdma.h | 16 +
8 files changed, 2421 insertions(+)
create mode 100644 Documentation/devicetree/bindings/dma/xilinx/xlnx,zynqmp-dpdma.yaml
create mode 100644 drivers/dma/xilinx/xilinx_dpdma.c
create mode 100644 include/dt-bindings/dma/xlnx-zynqmp-dpdma.h