regmap.txt 1.3 KB
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Device-Tree binding for regmap

The endianness mode of CPU & Device scenarios:
Index     Device     Endianness properties
---------------------------------------------------
1         BE         'big-endian'
2         LE         'little-endian'
8
3	  Native     'native-endian'
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For one device driver, which will run in different scenarios above
on different SoCs using the devicetree, we need one way to simplify
this.

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Optional properties:
- {big,little,native}-endian: these are boolean properties, if absent
  then the implementation will choose a default based on the device
  being controlled.  These properties are for register values and all
  the buffers only.  Native endian means that the CPU and device have
  the same endianness.
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Examples:
Scenario 1 : CPU in LE mode & device in LE mode.
dev: dev@40031000 {
	      compatible = "name";
	      reg = <0x40031000 0x1000>;
	      ...
};

Scenario 2 : CPU in LE mode & device in BE mode.
dev: dev@40031000 {
	      compatible = "name";
	      reg = <0x40031000 0x1000>;
	      ...
	      big-endian;
};

Scenario 3 : CPU in BE mode & device in BE mode.
dev: dev@40031000 {
	      compatible = "name";
	      reg = <0x40031000 0x1000>;
	      ...
};

Scenario 4 : CPU in BE mode & device in LE mode.
dev: dev@40031000 {
	      compatible = "name";
	      reg = <0x40031000 0x1000>;
	      ...
	      little-endian;
};