Re: [PATCH 09/30] dt-bindings: clock: mediatek: Describe MT8196 peripheral clock controllers

[AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>]

Il 23/06/25 14:12, Krzysztof Kozlowski ha scritto:
> On 23/06/2025 12:29, Laura Nao wrote:
>> +properties:
>> +  compatible:
>> +    items:
>> +      - enum:
>> +          - mediatek,mt8196-adsp
>> +          - mediatek,mt8196-imp-iic-wrap-c
>> +          - mediatek,mt8196-imp-iic-wrap-e
>> +          - mediatek,mt8196-imp-iic-wrap-n
>> +          - mediatek,mt8196-imp-iic-wrap-w
>> +          - mediatek,mt8196-mdpsys0
>> +          - mediatek,mt8196-mdpsys1
>> +          - mediatek,mt8196-pericfg-ao
>> +          - mediatek,mt8196-pextp0cfg-ao
>> +          - mediatek,mt8196-pextp1cfg-ao
>> +          - mediatek,mt8196-ufscfg-ao
>> +          - mediatek,mt8196-vencsys
>> +          - mediatek,mt8196-vencsys-c1
>> +          - mediatek,mt8196-vencsys-c2
>> +          - mediatek,mt8196-vdecsys
>> +          - mediatek,mt8196-vdecsys-soc
>> +      - const: syscon
> 
> Why everything is syscon?
> 
> 
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  '#clock-cells':
>> +    const: 1
>> +
>> +  '#reset-cells':
>> +    const: 1
>> +
>> +  mediatek,hardware-voter:
>> +    $ref: /schemas/types.yaml#/definitions/phandle
>> +    description: A phandle of the hw voter node
>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - '#clock-cells'
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    pericfg_ao: clock-controller@16640000 {
>> +        compatible = "mediatek,mt8196-pericfg-ao", "syscon";
>> +        reg = <0x16640000 0x1000>;
>> +        mediatek,hardware-voter = <&scp_hwv>;
>> +        #clock-cells = <1>;
>> +    };
>> +  - |
>> +    pextp0cfg_ao: clock-controller@169b0000 {
>> +        compatible = "mediatek,mt8196-pextp0cfg-ao", "syscon";
>> +        reg = <0x169b0000 0x1000>;
>> +        #clock-cells = <1>;
>> +        #reset-cells = <1>;
>> +    };
>> diff --git a/Documentation/devicetree/bindings/clock/mediatek,mt8196-sys-clock.yaml b/Documentation/devicetree/bindings/clock/mediatek,mt8196-sys-clock.yaml
>> new file mode 100644
>> index 000000000000..363ebe87c525
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/clock/mediatek,mt8196-sys-clock.yaml
>> @@ -0,0 +1,76 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/clock/mediatek,mt8196-sys-clock.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: MediaTek System Clock Controller for MT8196
>> +
>> +maintainers:
>> +  - Guangjie Song <guangjie.song@mediatek.com>
>> +  - Laura Nao <laura.nao@collabora.com>
>> +
>> +description: |
>> +  The clock architecture in MediaTek SoCs is structured like below:
>> +  PLLs -->
>> +          dividers -->
>> +                      muxes
>> +                           -->
>> +                              clock gate
>> +
>> +  The apmixedsys, apmixedsys_gp2, vlpckgen, armpll, ccipll, mfgpll and ptppll
>> +  provide most of the PLLs which are generated from the SoC's 26MHZ crystal oscillator.
>> +  The topckgen, topckgen_gp2 and vlpckgen provide dividers and muxes which
>> +  provide the clock source to other IP blocks.
>> +
>> +properties:
>> +  compatible:
>> +    items:
>> +      - enum:
>> +          - mediatek,mt8196-apmixedsys
>> +          - mediatek,mt8196-armpll-b-pll-ctrl
>> +          - mediatek,mt8196-armpll-bl-pll-ctrl
>> +          - mediatek,mt8196-armpll-ll-pll-ctrl
>> +          - mediatek,mt8196-apmixedsys-gp2
>> +          - mediatek,mt8196-ccipll-pll-ctrl
>> +          - mediatek,mt8196-mfgpll-pll-ctrl
>> +          - mediatek,mt8196-mfgpll-sc0-pll-ctrl
>> +          - mediatek,mt8196-mfgpll-sc1-pll-ctrl
>> +          - mediatek,mt8196-ptppll-pll-ctrl
>> +          - mediatek,mt8196-topckgen
>> +          - mediatek,mt8196-topckgen-gp2
>> +          - mediatek,mt8196-vlpckgen
>> +      - const: syscon
> 
> Why everything is syscon?

Like all other MediaTek SoCs - each sub-IP has its own clock controller, and all
of those sub-IPs have part of the system controller.

It's just a MediaTek SoC being a... MediaTek SoC.

> 
>> +
>> +  reg:
>> +    maxItems: 1
>> +
>> +  '#clock-cells':
>> +    const: 1
>> +
>> +  mediatek,hardware-voter:
>> +    $ref: /schemas/types.yaml#/definitions/phandle
>> +    description: A phandle of the hw voter node
> 
> Do not copy property name to description, but say something useful - for
> what? And why this cannot be or is not a proper interconnect?
> 

Laura, please check the commit description of my power domains HWV patches
here: 20250623120154.109429-8-angelogioacchino.delregno@collabora.com

...and follow what krzk just said which... well, my bad for not complaining
about this during internal reviewing.

>> +
>> +required:
>> +  - compatible
>> +  - reg
>> +  - '#clock-cells'
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    apmixedsys_clk: syscon@10000800 {
>> +        compatible = "mediatek,mt8196-apmixedsys", "syscon";
>> +        reg = <0x10000800 0x1000>;
>> +        #clock-cells = <1>;
>> +    };
>> +  - |
>> +    topckgen: syscon@10000000 {
>> +        compatible = "mediatek,mt8196-topckgen", "syscon";
>> +        reg = <0x10000000 0x800>;
>> +        mediatek,hardware-voter = <&scp_hwv>;
>> +        #clock-cells = <1>;
>> +    };
>> +
> 
> 
> 
>> +#define CLK_OVL1_DLO9					56
>> +#define CLK_OVL1_DLO10					57
>> +#define CLK_OVL1_DLO11					58
>> +#define CLK_OVL1_DLO12					59
>> +#define CLK_OVL1_OVLSYS_RELAY0				60
>> +#define CLK_OVL1_OVL_INLINEROT0				61
>> +#define CLK_OVL1_SMI					62
>> +
>> +
>> +/* VDEC_SOC_GCON_BASE */
>> +#define CLK_VDE1_LARB1_CKEN				0
>> +#define CLK_VDE1_LAT_CKEN				3
> 
> IDs increment by 1, not 3.

Thank you, Krzysztof - sharp as always!

Cheers,
Angelo