From a20625fb03df9d84378b63540c2ad6b34703af33 Mon Sep 17 00:00:00 2001 From: Paul Kocialkowski Date: Thu, 13 Sep 2018 10:51:54 -0400 Subject: [PATCH] media: dt-bindings: media: Document bindings for the Cedrus VPU driver This adds a device-tree binding document that specifies the properties used by the Cedrus VPU driver, as well as examples. Signed-off-by: Paul Kocialkowski Reviewed-by: Rob Herring Signed-off-by: Maxime Ripard Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab --- Documentation/devicetree/bindings/media/cedrus.txt | 54 ++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 Documentation/devicetree/bindings/media/cedrus.txt diff --git a/Documentation/devicetree/bindings/media/cedrus.txt b/Documentation/devicetree/bindings/media/cedrus.txt new file mode 100644 index 0000000..a089a0c --- /dev/null +++ b/Documentation/devicetree/bindings/media/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@4a000000 { + compatible = "shared-dma-pool"; + size = <0x6000000>; + alloc-ranges = <0x4a000000 0x6000000>; + reusable; + linux,cma-default; + }; +}; + +video-codec@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 = ; + allwinner,sram = <&ve_sram 1>; +}; -- 2.7.4