[PATCH v2 4/5] dt-bindings: clock: Document Exynos850 CMU bindings

Krzysztof Kozlowski krzysztof.kozlowski at canonical.com
Thu Oct 7 23:46:42 PDT 2021


On 07/10/2021 21:41, Sam Protsenko wrote:
> Provide dt-schema documentation for Exynos850 SoC clock controller.
> 
> Signed-off-by: Sam Protsenko <semen.protsenko at linaro.org>
> Acked-by: Chanwoo Choi <cw00.choi at samsung.com>
> ---
> Changes in v2:
>   - Dropped OSCCLK node declaration example
>   - Dropped UART node declaration example
>   - Added Ack tag by Chanwoo Choi
> 
>  .../clock/samsung,exynos850-clock.yaml        | 185 ++++++++++++++++++
>  1 file changed, 185 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml
> 
> diff --git a/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml b/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml
> new file mode 100644
> index 000000000000..79202e6e6402
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml
> @@ -0,0 +1,185 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/clock/samsung,exynos850-clock.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Samsung Exynos850 SoC clock controller
> +
> +maintainers:
> +  - Sam Protsenko <semen.protsenko at linaro.org>
> +  - Chanwoo Choi <cw00.choi at samsung.com>
> +  - Krzysztof Kozlowski <krzysztof.kozlowski at canonical.com>
> +  - Sylwester Nawrocki <s.nawrocki at samsung.com>
> +  - Tomasz Figa <tomasz.figa at gmail.com>
> +
> +description: |
> +  Exynos850 clock controller is comprised of several CMU units, generating
> +  clocks for different domains. Those CMU units are modeled as separate device
> +  tree nodes, and might depend on each other. Root clocks in that clock tree are
> +  two external clocks:: OSCCLK (26 MHz) and RTCCLK (32768 Hz). Those external
> +  clocks must be defined as fixed-rate clocks in dts.
> +
> +  CMU_TOP is a top-level CMU, where all base clocks are prepared using PLLs and
> +  dividers; all other leaf clocks (other CMUs) are usually derived from CMU_TOP.
> +
> +  Each clock is assigned an identifier and client nodes can use this identifier
> +  to specify the clock which they consume. All clocks that available for usage
> +  in clock consumer nodes are defined as preprocessor macros in
> +  'dt-bindings/clock/exynos850.h' header.
> +


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski at canonical.com>


Best regards,
Krzysztof



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