coresight-tmc: add CoreSight TMC driver

This driver manages CoreSight TMC (Trace Memory Controller) which
can act as a link or a sink depending upon its configuration. It
can present itself as an ETF (Embedded Trace FIFO) or ETR
(Embedded Trace Router).

ETF when configured in circular buffer mode acts as a trace
collection sink. When configured in HW fifo mode it acts as link.
ETR always acts as a sink and can be used to route data to memory
allocated in RAM.
Signed-off-by: Pratik Patel <pratikp@codeaurora.org>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/Kconfig.debug

@@ -1340,4 +1340,24 @@ menuconfig CORESIGHT
 	  a topological view of the CoreSight components based on a DT
 	  specification and configure the right serie of components when a
 	  trace source gets enabled.
+
+if CORESIGHT
+config CORESIGHT_LINKS_AND_SINKS
+	bool "CoreSight Link and Sink drivers"
+	help
+	  This enables support for CoreSight link and sink drivers that are
+	  responsible for transporting and collecting the trace data
+	  respectively.  Link and sinks are dynamically aggregated with a trace
+	  entity at run time to form a complete trace path.
+
+config CORESIGHT_LINK_AND_SINK_TMC
+	bool "Coresight generic TMC driver"
+	depends on CORESIGHT_LINKS_AND_SINKS
+	help
+	  This enables support for the Trace Memory Controller driver.  Depending
+	  on its configuration the device can act as a link (embedded trace router
+	  - ETR) or sink (embedded trace FIFO).  The driver complies with the
+	  generic implementation of the component without special enhancement or
+	  added features.
+endif
 endmenu

drivers/coresight/Makefile

@@ -3,3 +3,4 @@
 #
 obj-$(CONFIG_CORESIGHT) += coresight.o
 obj-$(CONFIG_OF) += of_coresight.o
+obj-$(CONFIG_CORESIGHT_LINK_AND_SINK_TMC) += coresight-tmc.o