Hi everyone, As part of Google Summer of Code, I've tasked myself with implementing DMA support for the earlier Allwinner platforms. This second round of patches is the result of said effort. The first patch is the actual driver to support these platforms. Patches three, four and five add the corresponding DMA node to the sun4i, sun5i and sun7i device trees. The second patch, involving the sunxi SPI driver, lets users do SPI transfers of >=64 bytes by using DMA. The first round of patches also had a patch for 8250_dw letting it use DMA as well, but there were some issues causing underruns and "too much work for IRQ", so I have dropped them. It's worth noting that Allwinner themselves don't use DMA transfers on their 8250 driver on the SDK. Patches six, seven and eight add the DMA properties to SPI so the first two patches can be used. Patches nine, ten and eleven are *only intended for testing*, and add a dummy SPIdev device to cubieboard, cubietruck and A10S-OLinuXino to facilitate testing with spidev_test. My main testing procedure for SPI has been modified versions of spidev_test from the kernel tree, with and without shorting MISO and MOSI. For memory to memory transfers, I have used dmatest.ko with various configurations. I have done testing on a cubieboard (A10, sun4i) and cubietruck (A20, sun7i) as well as an A10S-OLinuXino. You will find some extra remarks on individual patches after their descriptions. All comments are welcome. Thanks! Emilio López (8): dma: sun4i: Add support for the DMA engine on sun[457]i SoCs spi: sun4i: add DMA support ARM: sun4i: Add node to represent the DMA controller ARM: sun5i: Add nodes to represent the DMA controllers ARM: sun7i: Add node to represent the DMA controller ARM: sun4i: enable DMA on SPI ARM: sun5i: enable DMA on SPI ARM: sun7i: enable DMA on SPI .../devicetree/bindings/dma/sun4i-dma.txt | 45 + arch/arm/boot/dts/sun4i-a10.dtsi | 16 + arch/arm/boot/dts/sun5i-a10s.dtsi | 14 + arch/arm/boot/dts/sun5i-a13.dtsi | 14 + arch/arm/boot/dts/sun7i-a20.dtsi | 16 + drivers/dma/Kconfig | 10 + drivers/dma/Makefile | 1 + drivers/dma/sun4i-dma.c | 1025 ++++++++++++++++++++ drivers/spi/spi-sun4i.c | 155 ++- 9 files changed, 1285 insertions(+), 11 deletions(-) create mode 100644 Documentation/devicetree/bindings/dma/sun4i-dma.txt create mode 100644 drivers/dma/sun4i-dma.c -- 2.0.1 -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
