dmaengine: Add hisilicon k3 DMA engine driver

Add dmaengine driver for hisilicon k3 platform based on virt_dma
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Tested-by: Kai Yang <jean.yangkai@huawei.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

Documentation/devicetree/bindings/dma/k3dma.txt

+* Hisilicon K3 DMA controller
+
+See dma.txt first
+
+Required properties:
+- compatible: Should be "hisilicon,k3-dma-1.0"
+- reg: Should contain DMA registers location and length.
+- interrupts: Should contain one interrupt shared by all channel
+- #dma-cells: see dma.txt, should be 1, para number
+- dma-channels: physical channels supported
+- dma-requests: virtual channels supported, each virtual channel
+		have specific request line
+- clocks: clock required
+
+Example:
+
+Controller:
+		dma0: dma@fcd02000 {
+			compatible = "hisilicon,k3-dma-1.0";
+			reg = <0xfcd02000 0x1000>;
+			#dma-cells = <1>;
+			dma-channels = <16>;
+			dma-requests = <27>;
+			interrupts = <0 12 4>;
+			clocks = <&pclk>;
+			status = "disable";
+		};
+
+Client:
+Use specific request line passing from dmax
+For example, i2c0 read channel request line is 18, while write channel use 19
+
+		i2c0: i2c@fcb08000 {
+			compatible = "snps,designware-i2c";
+			dmas =	<&dma0 18          /* read channel */
+				 &dma0 19>;        /* write channel */
+			dma-names = "rx", "tx";
+		};
+
+		i2c1: i2c@fcb09000 {
+			compatible = "snps,designware-i2c";
+			dmas =	<&dma0 20          /* read channel */
+				 &dma0 21>;        /* write channel */
+			dma-names = "rx", "tx";
+		};
+

drivers/dma/Kconfig

@@ -300,6 +300,15 @@ config DMA_JZ4740
 	select DMA_ENGINE
 	select DMA_VIRTUAL_CHANNELS
 
+config K3_DMA
+	tristate "Hisilicon K3 DMA support"
+	depends on ARCH_HI3xxx
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Support the DMA engine for Hisilicon K3 platform
+	  devices.
+
 config DMA_ENGINE
 	bool
 

drivers/dma/Makefile

@@ -39,3 +39,4 @@ obj-$(CONFIG_MMP_TDMA) += mmp_tdma.o
 obj-$(CONFIG_DMA_OMAP) += omap-dma.o
 obj-$(CONFIG_MMP_PDMA) += mmp_pdma.o
 obj-$(CONFIG_DMA_JZ4740) += dma-jz4740.o
+obj-$(CONFIG_K3_DMA) += k3dma.o