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Message-ID: <f1d85b54-f0d6-4274-923c-2ad31eab2b19@collabora.com>
Date: Tue, 28 May 2024 12:24:50 +0200
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Subject: Re: [PATCH v6 2/8] dt-bindings: mailbox: Add property for CMDQ secure
 driver
To: "Jason-JH.Lin" <jason-jh.lin@mediatek.com>,
 Jassi Brar <jassisinghbrar@gmail.com>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 Rob Herring <robh+dt@kernel.org>, Matthias Brugger <matthias.bgg@gmail.com>,
 Chun-Kuang Hu <chunkuang.hu@kernel.org>
Cc: Conor Dooley <conor+dt@kernel.org>,
 Jason-ch Chen <jason-ch.chen@mediatek.com>,
 Singo Chang <singo.chang@mediatek.com>, Nancy Lin <nancy.lin@mediatek.com>,
 Shawn Sung <shawn.sung@mediatek.com>, linux-kernel@vger.kernel.org,
 devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
 linux-mediatek@lists.infradead.org, dri-devel@lists.freedesktop.org,
 Project_Global_Chrome_Upstream_Group@mediatek.com
References: <20240525230810.24623-1-jason-jh.lin@mediatek.com>
 <20240525230810.24623-3-jason-jh.lin@mediatek.com>
From: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Content-Language: en-US
In-Reply-To: <20240525230810.24623-3-jason-jh.lin@mediatek.com>
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Il 26/05/24 01:08, Jason-JH.Lin ha scritto:
> 1. Add mboxes property to define a GCE loopping thread as a secure IRQ
> handler.
> The CMDQ secure driver requests a mbox channel and sends a looping
> command to the GCE thread. The looping command will wait for a secure
> packet done event signal from secure world and then jump back to the
> first instuction. Each time it waits for an event, it notifies the
> CMDQ driver to perform the same action as the IRQ handler.
> 
> 2. Add gce-events property from gce-props.yaml to define a
> secure packet done signal in secure world.
> There are 1024 events IDs for GCE to use to execute instructions in
> the specific event happened. These events could be signaled by HW or SW
> and their value would be different in different SoC because of HW event
> IDs distribution range from 0 to 1023.
> If we set a static event ID: 855 for mt8188, it might be conflict the
> event ID original set in mt8195.
> So we define an event ID that will be set when GCE runs to the end of
> secure cmdq packet in the secure world.
> 
> This can reduce the latency of software communication between normal
> world and secure world. In addition, we can also remove the complex
> logic after the secure packet done in the secure world.
> 

Hello Jason,

Is this looping thread SoC specific, board specific or firmware specific?

Thanks,
Angelo

> Signed-off-by: Jason-JH.Lin <jason-jh.lin@mediatek.com>
> Signed-off-by: Hsiao Chien Sung <shawn.sung@mediatek.com>
> ---
>   .../devicetree/bindings/mailbox/mediatek,gce-mailbox.yaml | 8 +++++++-
>   1 file changed, 7 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/mailbox/mediatek,gce-mailbox.yaml b/Documentation/devicetree/bindings/mailbox/mediatek,gce-mailbox.yaml
> index cef9d7601398..6e5e848d61d9 100644
> --- a/Documentation/devicetree/bindings/mailbox/mediatek,gce-mailbox.yaml
> +++ b/Documentation/devicetree/bindings/mailbox/mediatek,gce-mailbox.yaml
> @@ -49,6 +49,10 @@ properties:
>       items:
>         - const: gce
>   
> +  mboxes:
> +    items:
> +      - description: GCE looping thread as a secure IRQ handler
> +
>   required:
>     - compatible
>     - "#mbox-cells"
> @@ -57,6 +61,8 @@ required:
>     - clocks
>   
>   allOf:
> +  - $ref: /schemas/mailbox/mediatek,gce-props.yaml#
> +
>     - if:
>         not:
>           properties:
> @@ -67,7 +73,7 @@ allOf:
>         required:
>           - clock-names
>   
> -additionalProperties: false
> +unevaluatedProperties: false
>   
>   examples:
>     - |