From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiubo Li Subject: [PATCHv3 1/2] dt/bindings: Add the DT binding documentation for endianness Date: Wed, 30 Apr 2014 12:43:48 +0800 Message-ID: <1398833029-29546-2-git-send-email-Li.Xiubo@freescale.com> References: <1398833029-29546-1-git-send-email-Li.Xiubo@freescale.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1398833029-29546-1-git-send-email-Li.Xiubo@freescale.com> Sender: linux-doc-owner@vger.kernel.org To: mark.rutland@arm.com, broonie@kernel.org Cc: gregkh@linuxfoundation.org, mpa@pengutronix.de, devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Xiubo Li List-Id: devicetree@vger.kernel.org Signed-off-by: Xiubo Li --- .../devicetree/bindings/endianness/endianness.txt | 47 ++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 Documentation/devicetree/bindings/endianness/endianness.txt diff --git a/Documentation/devicetree/bindings/endianness/endianness.txt b/Documentation/devicetree/bindings/endianness/endianness.txt new file mode 100644 index 0000000..49458a1 --- /dev/null +++ b/Documentation/devicetree/bindings/endianness/endianness.txt @@ -0,0 +1,47 @@ +Device-Tree binding for device endianness + +The endianness mode of CPU & Device scenarios: +Index CPU Device Endianess flag for DT bool property +------------------------------------------------------------ +1 LE LE - +2 LE BE 'big-endian{,-*}' +3 BE BE - +4 BE LE 'little-endian{,-*}' + +For one device driver, which will run in different scenarios above +on different SoCs using the devicetree, we need one way to simplify +this. + +Required properties: +- {big,little}-endian{,-*}: this is one boolean property. + +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{,-*}; +}; -- 1.8.4