lkml.org 
[lkml]   [2014]   [Nov]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH v3 1/3] devicetree: of: Add bindings for chosen node, stdout-path
    Date
    Add a global binding for the chosen node.
    Include a description of the stdout-path, and an explicit statement on
    its extra options in the context of a UART console.

    Opening description stolen from www.devicetree.org, and part of the
    remaining text provided by Mark Rutland.

    Signed-off-by: Leif Lindholm <leif.lindholm@linaro.org>
    ---
    Documentation/devicetree/bindings/chosen.txt | 42 ++++++++++++++++++++++++++
    1 file changed, 42 insertions(+)
    create mode 100644 Documentation/devicetree/bindings/chosen.txt

    diff --git a/Documentation/devicetree/bindings/chosen.txt b/Documentation/devicetree/bindings/chosen.txt
    new file mode 100644
    index 0000000..9cd74e9
    --- /dev/null
    +++ b/Documentation/devicetree/bindings/chosen.txt
    @@ -0,0 +1,42 @@
    +The chosen node
    +---------------
    +
    +The chosen node does not represent a real device, but serves as a place
    +for passing data between firmware and the operating system, like boot
    +arguments. Data in the chosen node does not represent the hardware.
    +
    +
    +stdout-path property
    +--------------------
    +
    +Device trees may specify the device to be used for boot console output
    +with a stdout-path property under /chosen, as described in ePAPR, e.g.
    +
    +/ {
    + chosen {
    + stdout-path = "/serial@f00:115200";
    + };
    +
    + serial@f00 {
    + compatible = "vendor,some-uart";
    + reg = <0xf00 0x10>;
    + };
    +};
    +
    +If the character ":" is present in the value, this terminates the path.
    +The meaning of any characters following the ":" is device-specific, and
    +must be specified in the relevant binding documentation.
    +
    +For UART devices, the format supported by uart_parse_options() is the
    +expected one. In this case, the format of the string is:
    +
    + <baud>{<parity>{<bits>{<flow>}}}
    +
    +where
    +
    + baud - baud rate in decimal
    + parity - 'n' (none), 'o', (odd) or 'e' (even)
    + bits - number of data bits
    + flow - 'r' (rts)
    +
    +For example: 115200n8r
    --
    1.7.10.4


    \
     
     \ /
      Last update: 2014-11-27 19:41    [W:4.218 / U:0.032 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site