ARM: keystone: Add minimal TI Keystone platform support

Texas Instruments Keystone family of multi-core devices are
based on ARM Cortex A15. Patch adds basic definitions for a
new Keystone sub-architecture in ARM.

The TCI66xxK2H Communications Infrastructure Keystone SoCs
are member of the C66x family based on TI's new KeyStone 2
multi-core SoC Architecture designed specifically for high
performance wireless and networking infrastructure applications.
The SOCs contains many subsystems like Cortex A15 ARM CorePacs,
C66XX DSP CorePacs, MSMC memory controller, Tera Net bus,
IP Network, Navigator, Hyperlink, 1G/10G Ethernet, Radio layers
and queue based communication systems.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: arm@kernel.org

Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
diff --git a/arch/arm/mach-keystone/Kconfig b/arch/arm/mach-keystone/Kconfig
new file mode 100644
index 0000000..aebe8cd
--- /dev/null
+++ b/arch/arm/mach-keystone/Kconfig
@@ -0,0 +1,14 @@
+config ARCH_KEYSTONE
+	bool "Texas Instruments Keystone Devices"
+	depends on ARCH_MULTI_V7
+	select CPU_V7
+	select ARM_GIC
+	select HAVE_ARM_ARCH_TIMER
+	select CLKSRC_MMIO
+	select GENERIC_CLOCKEVENTS
+	select HAVE_SCHED_CLOCK
+	select ARCH_WANT_OPTIONAL_GPIOLIB
+	select ARM_ERRATA_798181
+	help
+	  Support for boards based on the Texas Instruments Keystone family of
+	  SoCs.