From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- .../devicetree/bindings/regmap/regmap.txt | 29 ++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 Documentation/devicetree/bindings/regmap/regmap.txt (limited to 'Documentation/devicetree/bindings/regmap/regmap.txt') diff --git a/Documentation/devicetree/bindings/regmap/regmap.txt b/Documentation/devicetree/bindings/regmap/regmap.txt new file mode 100644 index 000000000..873096be0 --- /dev/null +++ b/Documentation/devicetree/bindings/regmap/regmap.txt @@ -0,0 +1,29 @@ +Devicetree binding for regmap + +Optional properties: + + little-endian, + big-endian, + native-endian: See common-properties.txt for a definition + +Note: +Regmap defaults to little-endian register access on MMIO based +devices, this is by far the most common setting. On CPU +architectures that typically run big-endian operating systems +(e.g. PowerPC), registers can be defined as big-endian and must +be marked that way in the devicetree. + +On SoCs that can be operated in both big-endian and little-endian +modes, with a single hardware switch controlling both the endianness +of the CPU and a byteswap for MMIO registers (e.g. many Broadcom MIPS +chips), "native-endian" is used to allow using the same device tree +blob in both cases. + +Examples: +Scenario 1 : a register set in big-endian mode. +dev: dev@40031000 { + compatible = "syscon"; + reg = <0x40031000 0x1000>; + big-endian; + ... +}; -- cgit v1.2.3