Re: [PATCH v2 1/2] dt-bindings: reset: mediatek: Add mt8188 SMI reset control binding

["CK Hu (胡俊光)" <ck.hu@mediatek.com>]

Hi, Friday:

On Wed, 2024-11-20 at 14:32 +0800, Friday Yang wrote:
> From: "Friday Yang" <friday.yang@mediatek.com>
> 
> To support SMI clamp and reset operation in genpd callback, add
> SMI LARB reset controller in the bindings. Add index in
> mt8188-resets.h to query the reset signal in the SMI reset
> control driver.
> 
> Signed-off-by: Friday Yang <friday.yang@mediatek.com>
> ---
>  .../bindings/reset/mediatek,smi-reset.yaml    | 53 +++++++++++++++++++
>  include/dt-bindings/reset/mt8188-resets.h     | 11 ++++
>  2 files changed, 64 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/reset/mediatek,smi-reset.yaml
> 
> diff --git a/Documentation/devicetree/bindings/reset/mediatek,smi-reset.yaml b/Documentation/devicetree/bindings/reset/mediatek,smi-reset.yaml
> new file mode 100644
> index 000000000000..77a6197a9846
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/reset/mediatek,smi-reset.yaml
> @@ -0,0 +1,53 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright (c) 2024 MediaTek Inc.
> +%YAML 1.2
> +---
> +$id: https://urldefense.com/v3/__http://devicetree.org/schemas/reset/mediatek,smi-reset.yaml*__;Iw!!CTRNKA9wMg0ARbw!gdXglQJh0-FDFibSUah2aNWBcdxp70BO2OQgeO0iq660S3-nixB7L2xJnKDsMlilUnctbSbP9KNv_Ot8e2aDow$ 
> +$schema: https://urldefense.com/v3/__http://devicetree.org/meta-schemas/core.yaml*__;Iw!!CTRNKA9wMg0ARbw!gdXglQJh0-FDFibSUah2aNWBcdxp70BO2OQgeO0iq660S3-nixB7L2xJnKDsMlilUnctbSbP9KNv_OvQ-6vNSA$ 
> +
> +title: MediaTek SMI Reset Controller
> +
> +maintainers:
> +  - Friday Yang <friday.yang@mediatek.com>
> +
> +description: |
> +  This reset controller node is used to perform reset management
> +  of SMI larbs on MediaTek platform. It is used to implement various
> +  reset functions required when SMI larbs apply clamp operation.
> +
> +  For list of all valid reset indices see
> +    <dt-bindings/reset/mt8188-resets.h> for MT8188.
> +
> +properties:
> +  compatible:
> +    enum:
> +      - mediatek,mt8188-smi-reset
> +
> +  "#reset-cells":
> +    const: 1
> +    description:
> +      The cell should be the device ID. SMI reset controller driver could
> +      query the reset signal of each SMI larb by device ID.
> +
> +  mediatek,larb-rst:
> +    $ref: /schemas/types.yaml#/definitions/phandle
> +    description:
> +      Phandle of each subsys clock controller. SMI larbs are located in
> +      these subsys. SMI needs to parse the node of each subsys clock
> +      controller to get the register address, and then apply the reset
> +      operation.
> +
> +required:
> +  - compatible
> +  - "#reset-cells"
> +  - mediatek,larb-rst
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    reset-controller {
> +        compatible = "mediatek,mt8188-smi-reset";
> +        #reset-cells = <1>;
> +        mediatek,larb-rst = <&imgsys1_dip_top>;

It seems that imgsys1-dip-top device [1] is a syscon (system controller) device not a pure clock controller.
It is similar to mmsys device [2].
mmsys driver is in [3].
Because clock maintainer insist on placing clock control part in clock driver folder,
so the clock control sub driver is in [4].
The reset control is in mmsys main driver, and main driver would probe the clock sub driver.
Refer to mmsys device to refine imgsys1-dip-top device.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/clock/mediatek,mt8188-clock.yaml?h=v6.12#n37
[2] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/arm/mediatek/mediatek,mmsys.yaml?h=v6.12
[3] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/soc/mediatek/mtk-mmsys.c?h=v6.12
[4] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/clk/mediatek/clk-mt8188-vdo0.c?h=v6.12

Regards,
CK

> +    };
> diff --git a/include/dt-bindings/reset/mt8188-resets.h b/include/dt-bindings/reset/mt8188-resets.h
> index 5a58c54e7d20..387a4beac688 100644
> --- a/include/dt-bindings/reset/mt8188-resets.h
> +++ b/include/dt-bindings/reset/mt8188-resets.h
> @@ -113,4 +113,15 @@
>  #define MT8188_VDO1_RST_HDR_GFX_FE1_DL_ASYNC	52
>  #define MT8188_VDO1_RST_HDR_VDO_BE_DL_ASYNC	53
> 
> +#define MT8188_SMI_RST_LARB10			0
> +#define MT8188_SMI_RST_LARB11A			1
> +#define MT8188_SMI_RST_LARB11C			2
> +#define MT8188_SMI_RST_LARB12			3
> +#define MT8188_SMI_RST_LARB11B			4
> +#define MT8188_SMI_RST_LARB15			5
> +#define MT8188_SMI_RST_LARB16B			6
> +#define MT8188_SMI_RST_LARB17B			7
> +#define MT8188_SMI_RST_LARB16A			8
> +#define MT8188_SMI_RST_LARB17A			9
> +
>  #endif  /* _DT_BINDINGS_RESET_CONTROLLER_MT8188 */
> --
> 2.46.0
> 
>