On Mon, Sep 27, 2021 at 3:34 PM Pali Rohár <pali@xxxxxxxxxx> wrote: > > On Monday 27 September 2021 15:17:59 Rob Herring wrote: > > On Wed, Sep 22, 2021 at 5:56 AM Pali Rohár <pali@xxxxxxxxxx> wrote: > > > > > > This change adds DT bindings documentation for device nodes with compatible > > > string "marvell,armada-3700-uart-clock". > > > > Please resend to the DT list so that checks run and this gets reviewed > > in a timely manner. > > OK > > > > Signed-off-by: Pali Rohár <pali@xxxxxxxxxx> > > > --- > > > .../bindings/clock/armada3700-uart-clock.yaml | 57 +++++++++++++++++++ > > > 1 file changed, 57 insertions(+) > > > create mode 100644 Documentation/devicetree/bindings/clock/armada3700-uart-clock.yaml > > > > > > diff --git a/Documentation/devicetree/bindings/clock/armada3700-uart-clock.yaml b/Documentation/devicetree/bindings/clock/armada3700-uart-clock.yaml > > > new file mode 100644 > > > index 000000000000..5bdb23e0ba3e > > > --- /dev/null > > > +++ b/Documentation/devicetree/bindings/clock/armada3700-uart-clock.yaml > > > @@ -0,0 +1,57 @@ > > > +# SPDX-License-Identifier: GPL-2.0 > > > > Dual license. checkpatch will tell you which ones. > > OK > > > > +%YAML 1.2 > > > +--- > > > +$id: http://devicetree.org/schemas/clock/marvell,armada-3700-uart-clock# > > > +$schema: http://devicetree.org/meta-schemas/core.yaml# > > > +title: Marvell Armada 3720 UART clocks > > > + > > > +properties: > > > + compatible: > > > + const: marvell,armada-3700-uart-clock > > > + > > > + reg: > > > + items: > > > + - description: UART Clock Control Register > > > + - description: UART 2 Baud Rate Divisor Register > > > + > > > + clocks: > > > + description: | > > > + List of parent clocks suitable for UART from following set: > > > + "TBG-A-P", "TBG-B-P", "TBG-A-S", "TBG-B-S", "xtal" > > > + UART clock can use one from this set and when more are provided > > > + then kernel would choose and configure the most suitable one. > > > + It is suggest to specify at least one TBG clock to achieve > > > + baudrates above 230400 and also to specify clock which bootloader > > > + used for UART (most probably xtal) for smooth boot log on UART. > > > + > > > + clock-names: > > > + items: > > > + - const: TBG-A-P > > > + - const: TBG-B-P > > > + - const: TBG-A-S > > > + - const: TBG-B-S > > > + - const: xtal > > > + minItems: 1 > > > + maxItems: 5 > > > > Don't need maxItems equal to length of 'items'. > > OK > > > > + > > > + '#clock-cells': > > > + const: 1 > > > + > > > +required: > > > + - compatible > > > + - reg > > > + - clocks > > > + - clock-names > > > + - '#clock-cells' > > > + > > > +additionalProperties: false > > > + > > > +examples: > > > + - | > > > + uartclk: uartclk@12000 { > > > > clock-controller@12010 > > > > > + compatible = "marvell,armada-3700-uart-clock"; > > > + reg = <0x12010 0x4>, <0x12210 0x4>; > > > > However, looks like this is part of some other block. > > Yes, it is part of UART block. > > Explanation is in commit message of patch 2/6. > > And also discussed here: > https://lore.kernel.org/linux-serial/20210812200804.i4kbcs6ut27mapd3@pali/ > > > The whole block > > needs a binding (or at least the parent and whatever sub-functions you > > know about). > > Whole UART block has already binding. Clock driver just needs access to > these clock bits of these two registers which are in UART block. HW > designers decided that clock which drives UART2 has configuration in > UART1 address space. As explained in commit message of patch 2/6 there > is no easy way how to deal with it in DTS backward compatible way. So > clock and UART driver shares mutex for accessing these two shared > registers, and these two registers are defined in all 3 DT nodes: UART1, > UART2 and UART-clock. That's awful. I guess I don't have a better suggestion. Rob
