irqchip: keystone: Add irq controller ip driver

On Keystone SOCs, DSP cores can send interrupts to ARM
host using the IRQ controller IP. It provides 28 IRQ
signals to ARM. The IRQ handler running on HOST OS can
identify DSP signal source by analyzing SRCCx bits in
IPCARx registers. This is one of the component used by
the IPC mechanism used on Keystone SOCs.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Link: https://lkml.kernel.org/r/1406126430-9978-1-git-send-email-grygorii.strashko@ti.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index b8632bf..c888964 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -113,3 +113,10 @@
 	  The primary irqchip invokes the crossbar's callback which inturn allocates
 	  a free irq and configures the IP. Thus the peripheral interrupts are
 	  routed to one of the free irqchip interrupt lines.
+
+config KEYSTONE_IRQ
+	tristate "Keystone 2 IRQ controller IP"
+	depends on ARCH_KEYSTONE
+	help
+		Support for Texas Instruments Keystone 2 IRQ controller IP which
+		is part of the Keystone 2 IPC mechanism