Re: [PATCH v2 3/8] dt-bindings: Add bindings for Tegra234 NVDEC

Rob Herring
2022-09-14T12:08:47Z

On Tue, Sep 13, 2022 at 04:14:41PM +0300, Mikko Perttunen wrote:
> From: Mikko Perttunen <mperttunen@nvidia.com>
>
> Update NVDEC bindings for Tegra234. This new engine version only has
> two memory clients, but now requires three clocks, and as a bigger
> change the engine loads firmware from a secure carveout configured by
> the bootloader.
>
> For the latter, we need to add a phandle to the memory controller
> to query the location of this carveout, and several other properties
> containing offsets into the firmware inside the carveout. These
> properties are intended to be populated through a device tree overlay
> configured at flashing time, so that the values correspond to the
> flashed NVDEC firmware.
>
> As the binding was getting large with many conditional properties,
> also split the Tegra234 version out into a separate file.
>
> Signed-off-by: Mikko Perttunen <mperttunen@nvidia.com>
> ---
> v2:
> - Split out into separate file to avoid complexity with
> conditionals etc.
> ---
> .../gpu/host1x/nvidia,tegra234-nvdec.yaml | 154 ++++++++++++++++++
> 1 file changed, 154 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/gpu/host1x/nvidia,tegra234-nvdec.yaml
>
> diff --git a/Documentation/devicetree/bindings/gpu/host1x/nvidia,tegra234-nvdec.yaml b/Documentation/devicetree/bindings/gpu/host1x/nvidia,tegra234-nvdec.yaml
> new file mode 100644
> index 000000000000..eab0475ca983
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpu/host1x/nvidia,tegra234-nvdec.yaml
> @@ -0,0 +1,154 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/gpu/host1x/nvidia,tegra234-nvdec.yaml#"
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#"
> +
> +title: Device tree binding for NVIDIA Tegra234 NVDEC
> +
> +description: |
> + NVDEC is the hardware video decoder present on NVIDIA Tegra210
> + and newer chips. It is located on the Host1x bus and typically
> + programmed through Host1x channels.
> +
> +maintainers:
> + - Thierry Reding <treding@gmail.com>
> + - Mikko Perttunen <mperttunen@nvidia.com>
> +
> +properties:
> + $nodename:
> + pattern: "^nvdec@[0-9a-f]*$"
> +
> + compatible:
> + enum:
> + - nvidia,tegra234-nvdec
> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + maxItems: 3
> +
> + clock-names:
> + items:
> + - const: nvdec
> + - const: fuse
> + - const: tsec_pka
> +
> + resets:
> + maxItems: 1
> +
> + reset-names:
> + items:
> + - const: nvdec
> +
> + power-domains:
> + maxItems: 1
> +
> + iommus:
> + maxItems: 1
> +
> + dma-coherent: true
> +
> + interconnects:
> + items:
> + - description: DMA read memory client
> + - description: DMA write memory client
> +
> + interconnect-names:
> + items:
> + - const: dma-mem
> + - const: write
> +
> + nvidia,memory-controller:
> + $ref: /schemas/types.yaml#/definitions/phandle
> + description:
> + phandle to the memory controller for determining carveout information.
> +
> + nvidia,bl-manifest-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to bootloader manifest from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.
> +
> + nvidia,bl-code-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to bootloader code section from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.
> +
> + nvidia,bl-data-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to bootloader data section from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.
> +
> + nvidia,os-manifest-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to operating system manifest from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.
> +
> + nvidia,os-code-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to operating system code section from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.
> +
> + nvidia,os-data-offset:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + Offset to operating system data section from beginning of firmware. Typically set as
> + part of a device tree overlay corresponding to flashed firmware.

I don't think DT is the place for describing your runtime loaded
firmware layout.

Rob