This adds mandatory device tree binding documentation for the clock related IP found on Marvell Berlin2 (BG2, BG2CD, and BG2Q) SoCs to the Berlin SoC binding documentation. Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@xxxxxxxxx> --- Changelog: v1->v2: - typo fixed (Reported by Alexandre Belloni) - reworked binding to not represent individual clocks but chip control IP/registers instead (Suggested by Mike Turquette) - dropped clock indices, refer to the include instead (Requested by Mike Turquette) - moved the documentation from bindings/clock to Marvell Berlin SoC binding, as there will be more functions (e.g. pinctrl) to describe Cc: Rob Herring <robh+dt@xxxxxxxxxx> Cc: Pawel Moll <pawel.moll@xxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Ian Campbell <ijc+devicetree@xxxxxxxxxxxxxx> Cc: Kumar Gala <galak@xxxxxxxxxxxxxx> Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> Cc: Mike Turquette <mturquette@xxxxxxxxxx> Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx> Cc: Jisheng Zhang <jszhang@xxxxxxxxxxx> Cc: devicetree@xxxxxxxxxxxxxxx Cc: linux-doc@xxxxxxxxxxxxxxx Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx --- .../devicetree/bindings/arm/marvell,berlin.txt | 47 ++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/Documentation/devicetree/bindings/arm/marvell,berlin.txt b/Documentation/devicetree/bindings/arm/marvell,berlin.txt index 0677003e1476..744a7ea569d4 100644 --- a/Documentation/devicetree/bindings/arm/marvell,berlin.txt +++ b/Documentation/devicetree/bindings/arm/marvell,berlin.txt @@ -23,3 +23,50 @@ SoC and board used. Currently known SoC compatibles are: ... } + +* Marvell Berlin2 chip control binding + +Marvell Berlin SoCs have a chip control register set providing several +individual registers dealing with pinmux, padmux, clock, reset, and secondary +CPU boot address. Unfortunately, the individual registers are spread among the +chip control registers, so there should be a single DT node only providing the +different functions which are described below. + +Required properties: +- compatible: shall be one of + "marvell,berlin2-chip-ctrl" for BG2 + "marvell,berlin2cd-chip-ctrl" for BG2CD + "marvell,berlin2q-chip-ctrl" for BG2Q +- reg: address and length of following register sets for + BG2/BG2CD: chip control register set + BG2Q: chip control register set and cpu pll registers + +* Clock provider binding + +As clock related registers are spread among the chip control registers, the +chip control node also provides the clocks. Marvell Berlin2 (BG2, BG2CD, BG2Q) +SoCs share the same IP for PLLs and clocks, with some minor differences in +features and register layout. + +Required properties: +- #clock-cells: shall be set to 1 +- clocks: clock specifiers referencing the core clock input clocks +- clock-names: array of strings describing the input clock specifiers above. + Allowed clock-names for the reference clocks are + "refclk" for the SoCs osciallator input on all SoCs, + and SoC-specific input clocks for + BG2/BG2CD: "video_ext0" for the external video clock input + +Clocks provided by core clocks shall be referenced by a clock specifier +indexing one of the provided clocks. Refer to dt-bindings/clock/berlin<soc>.h +for the corresponding index mapping. + +Example: + +chip: chip-control@ea0000 { + compatible = "marvell,berlin2-chip-ctrl"; + #clock-cells = <1>; + reg = <0xea0000 0x400>; + clocks = <&refclk>, <&externaldev 0>; + clock-names = "refclk", "video_ext0"; +}; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html