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2596e07a3e
The regmap binding talks about one thing, which is register endianess, and it gets almost every aspect of it wrong. This replaces the current text of the file with a version that makes more sense and that matches what we implement now. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes:a06c488da0
("regmap: Add explict native endian flag to DT bindings") Fixes:275876e208
("regmap: Add the DT binding documentation for endianness") Signed-off-by: Mark Brown <broonie@kernel.org>
30 lines
906 B
Plaintext
30 lines
906 B
Plaintext
Devicetree binding for regmap
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Optional properties:
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little-endian,
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big-endian,
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native-endian: See common-properties.txt for a definition
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Note:
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Regmap defaults to little-endian register access on MMIO based
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devices, this is by far the most common setting. On CPU
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architectures that typically run big-endian operating systems
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(e.g. PowerPC), registers can be defined as big-endian and must
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be marked that way in the devicetree.
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On SoCs that can be operated in both big-endian and little-endian
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modes, with a single hardware switch controlling both the endianess
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of the CPU and a byteswap for MMIO registers (e.g. many Broadcom MIPS
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chips), "native-endian" is used to allow using the same device tree
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blob in both cases.
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Examples:
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Scenario 1 : a register set in big-endian mode.
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dev: dev@40031000 {
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compatible = "syscon";
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reg = <0x40031000 0x1000>;
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big-endian;
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...
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};
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