docs: dts: Add documentation for hi6220 SoC ION node

Documentation for hi6220 SoC ION node

Signed-off-by: Chen Feng <puck.chen@hisilicon.com>
Signed-off-by: Yu Dongbin <yudongbin@hisilicon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/staging/ion/hi6220-ion.txt b/Documentation/devicetree/bindings/staging/ion/hi6220-ion.txt
new file mode 100644 (file)
index 0000000..c59e27c
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+++ b/Documentation/devicetree/bindings/staging/ion/hi6220-ion.txt
@@ -0,0 +1,31 @@
+Hi6220 SoC ION
+===================================================================
+Required properties:
+- compatible : "hisilicon,hi6220-ion"
+- list of the ION heaps
+       - heap name : maybe heap_sys_user@0
+       - heap id   : id should be unique in the system.
+       - heap base : base ddr address of the heap,0 means that
+       it is dynamic.
+       - heap size : memory size and 0 means it is dynamic.
+       - heap type : the heap type of the heap, please also
+       see the define in ion.h(drivers/staging/android/uapi/ion.h)
+-------------------------------------------------------------------
+Example:
+       hi6220-ion {
+               compatible = "hisilicon,hi6220-ion";
+               heap_sys_user@0 {
+                       heap-name = "sys_user";
+                       heap-id   = <0x0>;
+                       heap-base = <0x0>;
+                       heap-size = <0x0>;
+                       heap-type = "ion_system";
+               };
+               heap_sys_contig@0 {
+                       heap-name = "sys_contig";
+                       heap-id   = <0x1>;
+                       heap-base = <0x0>;
+                       heap-size = <0x0>;
+                       heap-type = "ion_system_contig";
+               };
+       };