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References: <20240119063224.29671-1-jason-jh.lin@mediatek.com> <20240119063224.29671-2-jason-jh.lin@mediatek.com>
In-Reply-To: <20240119063224.29671-2-jason-jh.lin@mediatek.com>
From: Fei Shao <fshao@chromium.org>
Date: Mon, 22 Jan 2024 11:44:48 +0800
Message-ID: <CAC=S1ng5v5-LSq6d-R-89N35qiKd7qa8FEo6qakWxrzibYvgSQ@mail.gmail.com>
Subject: Re: [PATCH v3 1/3] dt-bindings: mailbox: Add mediatek,gce-props.yaml
To: "Jason-JH.Lin" <jason-jh.lin@mediatek.com>
Cc: Rob Herring <robh+dt@kernel.org>, 
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>, Conor Dooley <conor+dt@kernel.org>, 
	Matthias Brugger <matthias.bgg@gmail.com>, 
	AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>, 
	Chun-Kuang Hu <chunkuang.hu@kernel.org>, devicetree@vger.kernel.org, 
	linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, 
	linux-mediatek@lists.infradead.org, dri-devel@lists.freedesktop.org, 
	linux-media@vger.kernel.org, linaro-mm-sig@lists.linaro.org, 
	Jason-ch Chen <jason-ch.chen@mediatek.com>, Johnson Wang <johnson.wang@mediatek.com>, 
	Singo Chang <singo.chang@mediatek.com>, Nancy Lin <nancy.lin@mediatek.com>, 
	Shawn Sung <shawn.sung@mediatek.com>, Project_Global_Chrome_Upstream_Group@mediatek.com
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On Fri, Jan 19, 2024 at 2:32=E2=80=AFPM Jason-JH.Lin <jason-jh.lin@mediatek=
com> wrote:
Hi Jason,

Just few nitpicks about typo:
>
> 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.
software

> 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@mediatek.com>
> ---
>  .../bindings/mailbox/mediatek,gce-props.yaml  | 52 +++++++++++++++++++
>  1 file changed, 52 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/mailbox/mediatek,gc=
e-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
Properties

> +
> +maintainers:
> +  - Houlong Wei <houlong.wei@mediatek.com>
> +
> +description:
> +  The Global Command Engine (GCE) is an instruction based, multi-threade=
d,
> +  single-core command dispatcher for MediaTek hardware. The Command Queu=
e
> +  (CMDQ) mailbox driver is a driver for GCE, implemented using the Linux
> +  mailbox framework. It is used to receive messages from mailbox consume=
rs
> +  and configure GCE to execute the specified instruction set in the mess=
age.
> +  We use mediatek,gce-mailbox.yaml to define the properties for CMDQ mai=
lbox
> +  driver. A device driver that uses the CMDQ driver to configure its har=
dware
> +  registers is a mailbox consumer. The mailbox consumer can request a ma=
ilbox
> +  channel corresponding to a GCE hardware thread to send a message, spec=
ifying
> +  that the GCE thread to configure its hardware. The mailbox provider ca=
n also
> +  reserved a mailbox channel to configure GCE hardware register by the s=
pcific
s/reserved/reserve/
s/spcific/specific/

Regards,
Fei


> +  GCE thread. This binding defines the common GCE properties for both ma=
ilbox
> +  provider and consumers.
> +
> +properties:
> +  mediatek,gce-events:
> +    description:
> +      GCE has an event table in SRAM, consisting of 1024 event IDs (0~10=
23).
> +      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 softwa=
re.
> +      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 w=
hen
> +      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 dr=
iver
> +      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
>
>