dmaengine: Add Intel LGM SoC DMA support.

Add DMA controller driver for Lightning Mountain (LGM) family of SoCs.

The main function of the DMA controller is the transfer of data from/to any
peripheral to/from the memory. A memory to memory copy capability can also
be configured.

This ldma driver is used for configure the device and channnels for data
and control paths.

Signed-off-by: Amireddy Mallikarjuna reddy <mallikarjunax.reddy@linux.intel.com>
Link: https://lore.kernel.org/r/5fc54eb7ccfad4f8dd812b66b884054fc55cf050.1606905330.git.mallikarjunax.reddy@linux.intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/Kconfig

@@ -740,6 +740,8 @@ source "drivers/dma/ti/Kconfig"
 
 source "drivers/dma/fsl-dpaa2-qdma/Kconfig"
 
+source "drivers/dma/lgm/Kconfig"
+
 # clients
 comment "DMA Clients"
 	depends on DMA_ENGINE

drivers/dma/Makefile

@@ -82,6 +82,7 @@ obj-$(CONFIG_XGENE_DMA) += xgene-dma.o
 obj-$(CONFIG_ZX_DMA) += zx_dma.o
 obj-$(CONFIG_ST_FDMA) += st_fdma.o
 obj-$(CONFIG_FSL_DPAA2_QDMA) += fsl-dpaa2-qdma/
+obj-$(CONFIG_INTEL_LDMA) += lgm/
 
 obj-y += mediatek/
 obj-y += qcom/

drivers/dma/lgm/Kconfig

@@ -0,0 +1,9 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config INTEL_LDMA
+	bool "Lightning Mountain centralized DMA controllers"
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	help
+	  Enable support for intel Lightning Mountain SOC DMA controllers.
+	  These controllers provide DMA capabilities for a variety of on-chip
+	  devices such as HSNAND and GSWIP (Gigabit Switch IP).

drivers/dma/lgm/Makefile

@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_INTEL_LDMA)	+= lgm-dma.o