soc: ti: add Keystone Navigator DMA support

The Keystone Navigator DMA driver sets up the dma channels and flows for
the QMSS(Queue Manager SubSystem) who triggers the actual data movements
across clients using destination queues. Every client modules like
NETCP(Network Coprocessor), SRIO(Serial Rapid IO) and CRYPTO
Engines has its own instance of packet dma hardware. QMSS has also
an internal packet DMA module which is used as an infrastructure
DMA with zero copy.

Initially this driver was proposed as DMA engine driver but since the
hardware is not typical DMA engine and hence doesn't comply with typical
DMA engine driver needs, that approach was naked. Link to that
discussion -
	https://lkml.org/lkml/2014/3/18/340

As aligned, now we pair the Navigator DMA with its companion Navigator
QMSS subsystem driver.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Olof Johansson <olof@lixom.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Sandeep Nair <sandeep_n@ti.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>

drivers/soc/ti/Kconfig

@@ -18,4 +18,14 @@ config KEYSTONE_NAVIGATOR_QMSS
 
 	  If unsure, say N.
 
+config KEYSTONE_NAVIGATOR_DMA
+	tristate "TI Keystone Navigator Packet DMA support"
+	depends on ARCH_KEYSTONE
+	help
+	  Say y tp enable support for the Keystone Navigator Packet DMA on
+	  on Keystone family of devices. It sets up the dma channels for the
+	  Queue Manager Sub System.
+
+	  If unsure, say N.
+
 endif # SOC_TI

drivers/soc/ti/Makefile

@@ -2,3 +2,4 @@
 # TI Keystone SOC drivers
 #
 obj-$(CONFIG_KEYSTONE_NAVIGATOR_QMSS)	+= knav_qmss_queue.o knav_qmss_acc.o
+obj-$(CONFIG_KEYSTONE_NAVIGATOR_DMA)	+= knav_dma.o