dt-bindings: rockchip-mailbox: Add mailbox controller document on Rockchip SoCs

This add the necessary binding documentation for mailbox
found on RK3368 SoC.

Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jassi Brar <jaswinder.singh@linaro.org>

diff --git a/Documentation/devicetree/bindings/mailbox/rockchip-mailbox.txt b/Documentation/devicetree/bindings/mailbox/rockchip-mailbox.txt
new file mode 100644 (file)
index 0000000..b6bb84a
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/rockchip-mailbox.txt
@@ -0,0 +1,32 @@
+Rockchip mailbox
+
+The Rockchip mailbox is used by the Rockchip CPU cores to communicate
+requests to MCU processor.
+
+Refer to ./mailbox.txt for generic information about mailbox device-tree
+bindings.
+
+Required properties:
+
+ - compatible: should be one of the following.
+   - "rockchip,rk3368-mbox" for rk3368
+ - reg: physical base address of the controller and length of memory mapped
+       region.
+ - interrupts: The interrupt number to the cpu. The interrupt specifier format
+       depends on the interrupt controller.
+ - #mbox-cells: Common mailbox binding property to identify the number
+       of cells required for the mailbox specifier. Should be 1
+
+Example:
+--------
+
+/* RK3368 */
+mbox: mbox@ff6b0000 {
+       compatible = "rockchip,rk3368-mailbox";
+       reg = <0x0 0xff6b0000 0x0 0x1000>,
+       interrupts = <GIC_SPI 146 IRQ_TYPE_LEVEL_HIGH>,
+                    <GIC_SPI 147 IRQ_TYPE_LEVEL_HIGH>,
+                    <GIC_SPI 148 IRQ_TYPE_LEVEL_HIGH>,
+                    <GIC_SPI 149 IRQ_TYPE_LEVEL_HIGH>;
+       #mbox-cells = <1>;
+};