Re: [PATCH v2 01/12] dt-bindings: clock: qcom: Add bindings for PDM GP_MN clock divider

[Dmitry Baryshkov]

On Mon, Oct 26, 2026 at 04:59:27PM +0530, Taniya Das wrote:
> Add device tree bindings for the Qualcomm Peripheral Web's PDM GP_MN
> clock divider. The hardware generates a fractional output frequency
> from a fixed input clock (typically TCXO4) using the relation
> Fout = Fin * (M / N), with duty cycle controlled by a separate D
> register. The clock output is routed over a gpio controlled pin.
> 
> Signed-off-by: Taniya Das <taniya.das@xxxxxxxxxxxxxxxx>
> ---
>  .../devicetree/bindings/clock/qcom,clk-gp-mnd.yaml | 98 ++++++++++++++++++++++
>  1 file changed, 98 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml b/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml
> new file mode 100644
> index 0000000000000000000000000000000000000000..8141f392c5d70acfc42cf1ff4b1722e1eff23afa
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/qcom,clk-gp-mnd.yaml
> @@ -0,0 +1,98 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/clock/qcom,clk-gp-mnd.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Qualcomm Peripheral Web's PDM GP_MN Clock Divider
> +
> +maintainers:
> +  - Taniya Das <taniya.das@xxxxxxxxxxxxxxxx>
> +
> +description: |
> +  The Peripheral Web's PDM GP_MN clock divider receives an input clock
> +  (TCXO4) with frequency Fin and generates an output clock with
> +  frequency Fout = Fin * (M / N) and a duty cycle controlled by D
> +  and routed over a gpio pin.
> +
> +  The divider is configured using three registers:
> +
> +  - GP_MN_CLK_MDIV: holds the M value.
> +  - GP_MN_CLK_NDIV: holds the ones complement of (N - M).
> +  - GP_MN_CLK_DUTY: holds the D value.
> +
> +  For every N input clock cycles the GP_MN produces M output clock
> +  cycles. D is the number of native clock cycles in which the GP_MN
> +  output is low, counted over 2^13 native clock cycles.
> +
> +  Hardware constraints:
> +
> +    M <= 511
> +    N <= 8191
> +    N > 2 * M
> +    M < D < (N - M)
> +    M and N must be coprime (no common divisor)
> +
> +properties:
> +  compatible:
> +    oneOf:
> +      - const: qcom,sc7280-gp-mnd

What was the first chip where these registers appeared? Was it present
on SDM845?

> +      - items:
> +          - enum:
> +              - qcom,sa8775p-gp-mnd
> +              - qcom,qcs8300-gp-mnd
> +              - qcom,qcs615-gp-mnd
> +          - const: qcom,sc7280-gp-mnd
> +
> +  reg:
> +    maxItems: 1
> +
> 

-- 
With best wishes
Dmitry