[PATCH v5 17/22] dt-bindings: media: Document bindings for the Sunxi-Cedrus VPU driver

Paul Kocialkowski
2018-07-10T08:01:09Z

This adds a device-tree binding document that specifies the properties
used by the Sunxi-Cedurs VPU driver, as well as examples.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
Reviewed-by: Rob Herring <robh@kernel.org>
---
.../bindings/media/sunxi-cedrus.txt | 54 +++++++++++++++++++
1 file changed, 54 insertions(+)
create mode 100644 Documentation/devicetree/bindings/media/sunxi-cedrus.txt

diff --git a/Documentation/devicetree/bindings/media/sunxi-cedrus.txt b/Documentation/devicetree/bindings/media/sunxi-cedrus.txt
new file mode 100644
index 000000000000..a089a0c1ff05
--- /dev/null
+++ b/Documentation/devicetree/bindings/media/sunxi-cedrus.txt
@@ -0,0 +1,54 @@
+Device-tree bindings for the VPU found in Allwinner SoCs, referred to as the
+Video Engine (VE) in Allwinner literature.
+
+The VPU can only access the first 256 MiB of DRAM, that are DMA-mapped starting
+from the DRAM base. This requires specific memory allocation and handling.
+
+Required properties:
+- compatible : must be one of the following compatibles:
+ - "allwinner,sun4i-a10-video-engine"
+ - "allwinner,sun5i-a13-video-engine"
+ - "allwinner,sun7i-a20-video-engine"
+ - "allwinner,sun8i-a33-video-engine"
+ - "allwinner,sun8i-h3-video-engine"
+- reg : register base and length of VE;
+- clocks : list of clock specifiers, corresponding to entries in
+ the clock-names property;
+- clock-names : should contain "ahb", "mod" and "ram" entries;
+- resets : phandle for reset;
+- interrupts : VE interrupt number;
+- allwinner,sram : SRAM region to use with the VE.
+
+Optional properties:
+- memory-region : CMA pool to use for buffers allocation instead of the
+ default CMA pool.
+
+Example:
+
+reserved-memory {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+
+ /* Address must be kept in the lower 256 MiBs of DRAM for VE. */
+ cma_pool: cma at 4a000000 {
+ compatible = "shared-dma-pool";
+ size = <0x6000000>;
+ alloc-ranges = <0x4a000000 0x6000000>;
+ reusable;
+ linux,cma-default;
+ };
+};
+
+video-codec at 1c0e000 {
+ compatible = "allwinner,sun7i-a20-video-engine";
+ reg = <0x01c0e000 0x1000>;
+
+ clocks = <&ccu CLK_AHB_VE>, <&ccu CLK_VE>,
+ <&ccu CLK_DRAM_VE>;
+ clock-names = "ahb", "mod", "ram";
+
+ resets = <&ccu RST_VE>;
+ interrupts = <GIC_SPI 53 IRQ_TYPE_LEVEL_HIGH>;
+ allwinner,sram = <&ve_sram 1>;
+};
--
2.17.1