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Diffstat (limited to 'Documentation/devicetree/bindings/soc/sunxi/sram.txt')
-rw-r--r-- | Documentation/devicetree/bindings/soc/sunxi/sram.txt | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/soc/sunxi/sram.txt b/Documentation/devicetree/bindings/soc/sunxi/sram.txt new file mode 100644 index 000000000000..067698112f5f --- /dev/null +++ b/Documentation/devicetree/bindings/soc/sunxi/sram.txt @@ -0,0 +1,72 @@ +Allwinnner SoC SRAM controllers +----------------------------------------------------- + +The SRAM controller found on most Allwinner devices is represented by +a regular node for the SRAM controller itself, with sub-nodes +reprensenting the SRAM handled by the SRAM controller. + +Controller Node +--------------- + +Required properties: +- compatible : "allwinner,sun4i-a10-sram-controller" +- reg : sram controller register offset + length + +SRAM nodes +---------- + +Each SRAM is described using the mmio-sram bindings documented in +Documentation/devicetree/bindings/misc/sram.txt + +Each SRAM will have SRAM sections that are going to be handled by the +SRAM controller as subnodes. These sections are represented following +once again the representation described in the mmio-sram binding. + +The valid sections compatible are: + - allwinner,sun4i-a10-sram-a3-a4 + - allwinner,sun4i-a10-sram-d + +Devices using SRAM sections +--------------------------- + +Some devices need to request to the SRAM controller to map an SRAM for +their exclusive use. + +The relationship between such a device and an SRAM section is +expressed through the allwinner,sram property, that will take a +phandle and an argument. + +This valid values for this argument are: + - 0: CPU + - 1: Device + +Example +------- +sram-controller@01c00000 { + compatible = "allwinner,sun4i-a10-sram-controller"; + reg = <0x01c00000 0x30>; + #address-cells = <1>; + #size-cells = <1>; + ranges; + + sram_a: sram@00000000 { + compatible = "mmio-sram"; + reg = <0x00000000 0xc000>; + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x00000000 0xc000>; + + emac_sram: sram-section@8000 { + compatible = "allwinner,sun4i-a10-sram-a3-a4"; + reg = <0x8000 0x4000>; + status = "disabled"; + }; + }; +}; + +emac: ethernet@01c0b000 { + compatible = "allwinner,sun4i-a10-emac"; + ... + + allwinner,sram = <&emac_sram 1>; +}; |