Documentation: bindings: Add DT bindings for ARM Juno boards.

List the required properties and nodes used to describe the
ARM Juno boards.

Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>

diff --git a/Documentation/devicetree/bindings/arm/arm-boards b/Documentation/devicetree/bindings/arm/arm-boards
index b78564b2b2019e06a4fea1863191d2cab6303ee2..1a709970e7f7826aba3de7847fcf964389e237e3 100644 (file)
--- a/Documentation/devicetree/bindings/arm/arm-boards
+++ b/Documentation/devicetree/bindings/arm/arm-boards
@@ -157,3 +157,69 @@ Example:
 
        };
 };
+
+ARM Versatile Express Boards
+-----------------------------
+For details on the device tree bindings for ARM Versatile Express boards
+please consult the vexpress.txt file in the same directory as this file.
+
+ARM Juno Boards
+----------------
+The Juno boards are targeting development for AArch64 systems. The first
+iteration, Juno r0, is a vehicle for evaluating big.LITTLE on AArch64,
+with the second iteration, Juno r1, mainly aimed at development of PCIe
+based systems. Juno r1 also has support for AXI masters placed on the TLX
+connectors to join the coherency domain.
+
+Juno boards are described in a similar way to ARM Versatile Express boards,
+with the motherboard part of the hardware being described in a separate file
+to highlight the fact that is part of the support infrastructure for the SoC.
+Juno device tree bindings also share the Versatile Express bindings as
+described under the RS1 memory mapping.
+
+Required properties (in root node):
+       compatible = "arm,juno";        /* For Juno r0 board */
+       compatible = "arm,juno-r1";     /* For Juno r1 board */
+
+Required nodes:
+The description for the board must include:
+   - a "psci" node describing the boot method used for the secondary CPUs.
+     A detailed description of the bindings used for "psci" nodes is present
+     in the psci.txt file.
+   - a "cpus" node describing the available cores and their associated
+     "enable-method"s. For more details see cpus.txt file.
+
+Example:
+
+/dts-v1/;
+/ {
+       model = "ARM Juno development board (r0)";
+       compatible = "arm,juno", "arm,vexpress";
+       interrupt-parent = <&gic>;
+       #address-cells = <2>;
+       #size-cells = <2>;
+
+       cpus {
+               #address-cells = <2>;
+               #size-cells = <0>;
+
+               A57_0: cpu@0 {
+                       compatible = "arm,cortex-a57","arm,armv8";
+                       reg = <0x0 0x0>;
+                       device_type = "cpu";
+                       enable-method = "psci";
+               };
+
+               .....
+
+               A53_0: cpu@100 {
+                       compatible = "arm,cortex-a53","arm,armv8";
+                       reg = <0x0 0x100>;
+                       device_type = "cpu";
+                       enable-method = "psci";
+               };
+
+               .....
+       };
+
+};