Re: [PATCH v3 1/3] dt-bindings: mailbox: Add mediatek,gce-props.yaml

[Conor Dooley]

Rob,

On Fri, Jan 19, 2024 at 02:32:22PM +0800, Jason-JH.Lin wrote:
> Add mediatek,gce-props.yaml for common GCE properties that is used for
> both mailbox providers and consumers. We place the common property
> "mediatek,gce-events" in this binding currently.
> 
> The property "mediatek,gce-events" is used for GCE event ID corresponding
> to a hardware event signal sent by the hardware or a sofware driver.
> If the mailbox providers or consumers want to manipulate the value of
> the event ID, they need to know the specific event ID.
> 
> Signed-off-by: Jason-JH.Lin <jason-jh.lin@xxxxxxxxxxxx>
> ---
>  .../bindings/mailbox/mediatek,gce-props.yaml  | 52 +++++++++++++++++++

Is bindings/mailbox the correct directory to put this in?

>  1 file changed, 52 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/mediatek,gce-props.yaml
> 
> diff --git a/Documentation/devicetree/bindings/mailbox/mediatek,gce-props.yaml b/Documentation/devicetree/bindings/mailbox/mediatek,gce-props.yaml
> new file mode 100644
> index 000000000000..68b519ff089f
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mailbox/mediatek,gce-props.yaml
> @@ -0,0 +1,52 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mailbox/mediatek,gce-props.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: MediaTek Global Command Engine Common Propertes
> +
> +maintainers:
> +  - Houlong Wei <houlong.wei@xxxxxxxxxxxx>
> +
> +description:
> +  The Global Command Engine (GCE) is an instruction based, multi-threaded,
> +  single-core command dispatcher for MediaTek hardware. The Command Queue
> +  (CMDQ) mailbox driver is a driver for GCE, implemented using the Linux
> +  mailbox framework. It is used to receive messages from mailbox consumers
> +  and configure GCE to execute the specified instruction set in the message.
> +  We use mediatek,gce-mailbox.yaml to define the properties for CMDQ mailbox
> +  driver. A device driver that uses the CMDQ driver to configure its hardware
> +  registers is a mailbox consumer. The mailbox consumer can request a mailbox
> +  channel corresponding to a GCE hardware thread to send a message, specifying
> +  that the GCE thread to configure its hardware. The mailbox provider can also
> +  reserved a mailbox channel to configure GCE hardware register by the spcific
> +  GCE thread. This binding defines the common GCE properties for both mailbox
> +  provider and consumers.
> +
> +properties:
> +  mediatek,gce-events:
> +    description:
> +      GCE has an event table in SRAM, consisting of 1024 event IDs (0~1023).
> +      Each event ID has a boolean event value with the default value 0.
> +      The property mediatek,gce-events is used to obtain the event IDs.
> +      Some gce-events are hardware-bound and cannot be changed by software.
> +      For instance, in MT8195, when VDO0_MUTEX is stream done, VDO_MUTEX will
> +      send an event signal to GCE, setting the value of event ID 597 to 1.
> +      Similarly, in MT8188, the value of event ID 574 will be set to 1 when
> +      VOD0_MUTEX is stream done.
> +      On the other hand, some gce-events are not hardware-bound and can be
> +      changed by software. For example, in MT8188, we can set the value of
> +      event ID 855, which is not bound to any hardware, to 1 when the driver
> +      in the secure world completes a task. However, in MT8195, event ID 855
> +      is already bound to VDEC_LAT1, so we need to select another event ID to
> +      achieve the same purpose. This event ID can be any ID that is not bound
> +      to any hardware and is not yet used in any software driver.
> +      To determine if the event ID is bound to the hardware or used by a
> +      software driver, refer to the GCE header
> +      include/dt-bindings/gce/<chip>-gce.h of each chip.
> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> +    minItems: 1
> +    maxItems: 1024
> +
> +additionalProperties: true
> -- 
> 2.18.0
>

Attachment: signature.asc
Description: PGP signature