dmaengine: ti: New driver for K3 UDMA

Split patch for review containing: defines, structs, io and low level
functions and interrupt callbacks.

DMA driver for
Texas Instruments K3 NAVSS Unified DMA – Peripheral Root Complex (UDMA-P)

The UDMA-P is intended to perform similar (but significantly upgraded) functions
as the packet-oriented DMA used on previous SoC devices. The UDMA-P module
supports the transmission and reception of various packet types. The UDMA-P is
architected to facilitate the segmentation and reassembly of SoC DMA data
structure compliant packets to/from smaller data blocks that are natively
compatible with the specific requirements of each connected peripheral. Multiple
Tx and Rx channels are provided within the DMA which allow multiple segmentation
or reassembly operations to be ongoing. The DMA controller maintains state
information for each of the channels which allows packet segmentation and
reassembly operations to be time division multiplexed between channels in order
to share the underlying DMA hardware. An external DMA scheduler is used to
control the ordering and rate at which this multiplexing occurs for Transmit
operations. The ordering and rate of Receive operations is indirectly controlled
by the order in which blocks are pushed into the DMA on the Rx PSI-L interface.

The UDMA-P also supports acting as both a UTC and UDMA-C for its internal
channels. Channels in the UDMA-P can be configured to be either Packet-Based or
Third-Party channels on a channel by channel basis.

The initial driver supports:
- MEM_TO_MEM (TR mode)
- DEV_TO_MEM (Packet / TR mode)
- MEM_TO_DEV (Packet / TR mode)
- Cyclic (Packet / TR mode)
- Metadata for descriptors

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Link: https://lore.kernel.org/r/20191223110458.30766-11-peter.ujfalusi@ti.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>

drivers/dma/ti/Kconfig

@@ -34,6 +34,19 @@ config DMA_OMAP
 	  Enable support for the TI sDMA (System DMA or DMA4) controller. This
 	  DMA engine is found on OMAP and DRA7xx parts.
 
+config TI_K3_UDMA
+	bool "Texas Instruments UDMA support"
+	depends on ARCH_K3 || COMPILE_TEST
+	depends on TI_SCI_PROTOCOL
+	depends on TI_SCI_INTA_IRQCHIP
+	select DMA_ENGINE
+	select DMA_VIRTUAL_CHANNELS
+	select TI_K3_RINGACC
+	select TI_K3_PSIL
+        help
+	  Enable support for the TI UDMA (Unified DMA) controller. This
+	  DMA engine is used in AM65x and j721e.
+
 config TI_K3_PSIL
 	bool
 

drivers/dma/ti/Makefile

@@ -2,5 +2,6 @@
 obj-$(CONFIG_TI_CPPI41) += cppi41.o
 obj-$(CONFIG_TI_EDMA) += edma.o
 obj-$(CONFIG_DMA_OMAP) += omap-dma.o
+obj-$(CONFIG_TI_K3_UDMA) += k3-udma.o
 obj-$(CONFIG_TI_K3_PSIL) += k3-psil.o k3-psil-am654.o k3-psil-j721e.o
 obj-$(CONFIG_TI_DMA_CROSSBAR) += dma-crossbar.o