All the sub-blocks of Allwinner A64 DE2 needs the SRAM C on A64 SoC to
be claimed, otherwise the whole DE2 space is inaccessible.
Add a device tree binding of the DE2 part as a sub-bus.
Signed-off-by: Icenowy Zheng <icen...@aosc.io>
---
.../devicetree/bindings/bus/sun50i-de2-bus.txt | 37 ++++++++++++++++++++++
1 file changed, 37 insertions(+)
create mode 100644 Documentation/devicetree/bindings/bus/sun50i-de2-bus.txt
diff --git a/Documentation/devicetree/bindings/bus/sun50i-de2-bus.txt
b/Documentation/devicetree/bindings/bus/sun50i-de2-bus.txt
new file mode 100644
index 000000000000..87dfb33fb3be
--- /dev/null
+++ b/Documentation/devicetree/bindings/bus/sun50i-de2-bus.txt
@@ -0,0 +1,37 @@
+Device tree bindings for Allwinner A64 DE2 bus
+
+The Allwinner A64 DE2 is on a special bus, which needs a SRAM region (SRAM C)
+to be claimed for enabling the access.
+
+Required properties:
+
+ - compatible: Should contain "allwinner,sun50i-a64-de2"
+ - reg: A resource specifier for the register space
+ - #address-cells: Must be set to 1
+ - #size-cells: Must be set to 1
+ - ranges: Must be set up to map the address space inside the
+ DE2, for the sub-blocks of DE2.
+ - allwinner,sram: the SRAM that needs to be claimed
+
+Example:
+
+ de2@1000000 {
+ compatible = "allwinner,sun50i-a64-de2";
+ reg = <0x1000000 0x400000>;
+ allwinner,sram = <&de2_sram 1>;
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0x1000000 0x400000>;
+
+ display_clocks: clock@0 {
+ compatible = "allwinner,sun50i-a64-de2-clk";
+ reg = <0x0 0x100000>;
+ clocks = <&ccu CLK_DE>,
+ <&ccu CLK_BUS_DE>;
+ clock-names = "mod",
+ "bus";
+ resets = <&ccu RST_BUS_DE>;
+ #clock-cells = <1>;
+ #reset-cells = <1>;
+ };
+ };
--
2.15.1
