[RFC V2 PATCH 0/3] net: axienet: Introduce dmaengine

From: Sarath Babu Naidu Gaddam
Date: Tue Sep 20 2022 - 01:57:22 EST


The axiethernet driver now uses the dmaengine framework to communicate
with the xilinx DMAengine driver(AXIDMA, MCDMA). The inspiration behind
this dmaengine adoption is to reuse the in-kernel xilinx dma engine
driver[1] and remove redundant dma programming sequence[2] from the
ethernet driver. This simplifies the ethernet driver and also makes
it generic to be hooked to any complaint dma IP i.e AXIDMA, MCDMA
without any modification.

This initial version is a proof of concept and validated with a ping test
on an AXI ethernet subsystem 1G + xilinx AXI DMA design. There is an
anticipated performance impact due to the adoption of the dmaengine
framework. The plan is to revisit it once all required functional
features are implemented.

The dmaengine framework was extended for metadata API support during
the axidma RFC[3] discussion. However, it still needs further enhancements
to make it well suited for ethernet usecases.

Comments, suggestions, thoughts to implement remaining functional features
are very welcome!

Changes in V2:
1) Add ethtool get/set coalesce and DMA reset using DMAengine framework.
2) Add performance numbers.
3) Remove .txt and change the name of file to xlnx,axiethernet.yaml.
4) Fix DT check warning(Fix DT check warning('device_type' does not match
any of the regexes:'pinctrl-[0-9]+' From schema: Documentation/
devicetree/bindings/net/xilinx_axienet.yaml).

Radhey Shyam Pandey (3):
dt-bindings: net: xilinx_axienet:convert bindings document to yaml
dt-bindings: net: xilinx_axienet: Introduce dmaengine binding support
net: axienet: Introduce dmaengine support

.../devicetree/bindings/net/xilinx_axienet.txt | 99 --
.../devicetree/bindings/net/xlnx,axiethernet.yaml | 159 +++
MAINTAINERS | 1 +
drivers/net/ethernet/xilinx/xilinx_axienet.h | 169 +---
drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 1165 ++++----------------
5 files changed, 398 insertions(+), 1195 deletions(-)
delete mode 100644 Documentation/devicetree/bindings/net/xilinx_axienet.txt
create mode 100644 Documentation/devicetree/bindings/net/xlnx,axiethernet.yaml