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

Jason-JH.Lin jason-jh.lin at mediatek.com
Sat May 25 16:08:04 PDT 2024


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 at mediatek.com>
Signed-off-by: Hsiao Chien Sung <shawn.sung at 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:
   - |
-- 
2.18.0




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