Re: [PATCH v4 2/2] dt-bindings: media: imx-jpeg: Assign slot for imx jpeg encoder/decoder

[Conor Dooley <conor@kernel.org>]

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Hi,

On Tue, Sep 26, 2023 at 06:10:00PM +0800, Ming Qian wrote:
> There are total 4 slots available in the IP, and we only need to use one
> slot in one os, assign a single slot, configure interrupt and power
> domain only for 1 slot, not for the all 4 slots.
> 
> Signed-off-by: Ming Qian <ming.qian@nxp.com>
> ---
> v4
> - improve commit message

> - don't make an ABI break

What does this mean? Can you please try to explain things a bit more
clearly in your changelogs?

Also, where is the code that actually makes use of these properties?

> v3
> - add vender prefix, change property slot to nxp,slot
> - add type for property slot
> 
>  .../bindings/media/nxp,imx8-jpeg.yaml         | 45 +++++++++----------
>  1 file changed, 21 insertions(+), 24 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/media/nxp,imx8-jpeg.yaml b/Documentation/devicetree/bindings/media/nxp,imx8-jpeg.yaml
> index 3d9d1db37040..4bcfc815c894 100644
> --- a/Documentation/devicetree/bindings/media/nxp,imx8-jpeg.yaml
> +++ b/Documentation/devicetree/bindings/media/nxp,imx8-jpeg.yaml
> @@ -32,19 +32,26 @@ properties:
>      maxItems: 1
>  
>    interrupts:
> -    description: |
> -      There are 4 slots available in the IP, which the driver may use
> -      If a certain slot is used, it should have an associated interrupt
> -      The interrupt with index i is assumed to be for slot i
> -    minItems: 1               # At least one slot is needed by the driver
> -    maxItems: 4               # The IP has 4 slots available for use
> +    description:
> +      Interrupt number for slot
> +    maxItems: 1

So, what happens to users that already exist that have 2, 3 or 4
interrupts? Your commit message says:
> There are total 4 slots available in the IP, and we only need to use one
> slot in one os, assign a single slot, configure interrupt and power
> domain only for 1 slot, not for the all 4 slots.

Note that "only need to use one" doesn't mean that a user might not
want to use more than one. Is it possible to use more than one slot?

Also, if the interrupt numbers map 1:1 to slots, as the previous binding
states, why do you even need this new "nxp,slot" property?

Thanks,
Conor.

>  
>    power-domains:
>      description:
>        List of phandle and PM domain specifier as documented in
>        Documentation/devicetree/bindings/power/power_domain.txt
> -    minItems: 2               # Wrapper and 1 slot
> -    maxItems: 5               # Wrapper and 4 slots
> +    minItems: 1               # VPUMIX
> +    maxItems: 2               # Wrapper and 1 slot
> +
> +  nxp,slot:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Integer number of slot index used. There are 4 slots available in the IP,
> +      and driver can use a certain slot, it should have an associated interrupt
> +      and power-domain. In theory, it supports 4 os or vm. If not specified, 0
> +      is used by default.
> +    minimum: 0
> +    maximum: 3
>  
>  required:
>    - compatible
> @@ -62,28 +69,18 @@ examples:
>      jpegdec: jpegdec@58400000 {
>          compatible = "nxp,imx8qxp-jpgdec";
>          reg = <0x58400000 0x00050000 >;
> -        interrupts = <GIC_SPI 309 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 310 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 311 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 312 IRQ_TYPE_LEVEL_HIGH>;
> +        interrupts = <GIC_SPI 309 IRQ_TYPE_LEVEL_HIGH>;
>          power-domains = <&pd IMX_SC_R_MJPEG_DEC_MP>,
> -                        <&pd IMX_SC_R_MJPEG_DEC_S0>,
> -                        <&pd IMX_SC_R_MJPEG_DEC_S1>,
> -                        <&pd IMX_SC_R_MJPEG_DEC_S2>,
> -                        <&pd IMX_SC_R_MJPEG_DEC_S3>;
> +                        <&pd IMX_SC_R_MJPEG_DEC_S0>;
> +        nxp,slot = <0>;
>      };
>  
>      jpegenc: jpegenc@58450000 {
>          compatible = "nxp,imx8qm-jpgenc", "nxp,imx8qxp-jpgenc";
>          reg = <0x58450000 0x00050000 >;
> -        interrupts = <GIC_SPI 305 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 306 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 307 IRQ_TYPE_LEVEL_HIGH>,
> -                     <GIC_SPI 308 IRQ_TYPE_LEVEL_HIGH>;
> +        interrupts = <GIC_SPI 305 IRQ_TYPE_LEVEL_HIGH>;
>          power-domains = <&pd IMX_SC_R_MJPEG_ENC_MP>,
> -                        <&pd IMX_SC_R_MJPEG_ENC_S0>,
> -                        <&pd IMX_SC_R_MJPEG_ENC_S1>,
> -                        <&pd IMX_SC_R_MJPEG_ENC_S2>,
> -                        <&pd IMX_SC_R_MJPEG_ENC_S3>;
> +                        <&pd IMX_SC_R_MJPEG_ENC_S0>;
> +        nxp,slot = <0>;
>      };
>  ...
> -- 
> 2.38.1
> 

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