[v6,2/8] dt-bindings: mailbox: Add property for CMDQ secure driver

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.

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(-)

On Sun, 26 May 2024 07:08:04 +0800, Jason-JH.Lin wrote:
> 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.
> 
> 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(-)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/mailbox/mediatek,gce-mailbox.example.dtb: mailbox@10212000: False schema does not allow {'compatible': ['mediatek,mt8173-gce'], 'reg': [[0, 270606336, 0, 4096]], 'interrupts': [[0, 135, 8]], '#mbox-cells': [[2]], 'clocks': [[4294967295, 4]], 'clock-names': ['gce'], '$nodename': ['mailbox@10212000']}
	from schema $id: http://devicetree.org/schemas/mailbox/mediatek,gce-mailbox.yaml#

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240525230810.24623-3-jason-jh.lin@mediatek.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

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:
>     - |