48 lines
1.2 KiB
Plaintext
48 lines
1.2 KiB
Plaintext
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Device-Tree binding for regmap
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The endianness mode of CPU & Device scenarios:
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Index Device Endianness properties
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---------------------------------------------------
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1 BE 'big-endian'
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2 LE 'little-endian'
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For one device driver, which will run in different scenarios above
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on different SoCs using the devicetree, we need one way to simplify
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this.
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Required properties:
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- {big,little}-endian: these are boolean properties, if absent
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meaning that the CPU and the Device are in the same endianness mode,
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these properties are for register values and all the buffers only.
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Examples:
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Scenario 1 : CPU in LE mode & device in LE mode.
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dev: dev@40031000 {
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compatible = "name";
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reg = <0x40031000 0x1000>;
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...
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};
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Scenario 2 : CPU in LE mode & device in BE mode.
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dev: dev@40031000 {
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compatible = "name";
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reg = <0x40031000 0x1000>;
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...
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big-endian;
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};
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Scenario 3 : CPU in BE mode & device in BE mode.
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dev: dev@40031000 {
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compatible = "name";
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reg = <0x40031000 0x1000>;
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...
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};
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Scenario 4 : CPU in BE mode & device in LE mode.
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dev: dev@40031000 {
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compatible = "name";
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reg = <0x40031000 0x1000>;
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...
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little-endian;
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};
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