[PATCH v4 4/8] dt-bindings: mailbox: Add MT8196 GPUEB Mailbox

Nicolas Frattaroli
2025-09-23T11:41:12Z

The MediaTek MT8196 SoC includes an embedded MCU referred to as "GPUEB",
acting as glue logic to control power and frequency of the Mali GPU.
This MCU runs special-purpose firmware for this use, and the main
application processor communicates with it through a mailbox.

Add a binding that describes this mailbox.

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
.../mailbox/mediatek,mt8196-gpueb-mbox.yaml | 64 ++++++++++++++++++++++
1 file changed, 64 insertions(+)

diff --git a/Documentation/devicetree/bindings/mailbox/mediatek,mt8196-gpueb-mbox.yaml b/Documentation/devicetree/bindings/mailbox/mediatek,mt8196-gpueb-mbox.yaml
new file mode 100644
index 0000000000000000000000000000000000000000..ab5b780cb83a708a3897ca1a440131d97b56c3a6
--- /dev/null
+++ b/Documentation/devicetree/bindings/mailbox/mediatek,mt8196-gpueb-mbox.yaml
@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mailbox/mediatek,mt8196-gpueb-mbox.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MFlexGraphics GPUEB Mailbox Controller
+
+maintainers:
+ - Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
+
+properties:
+ compatible:
+ enum:
+ - mediatek,mt8196-gpueb-mbox
+
+ reg:
+ items:
+ - description: mailbox data registers
+ - description: mailbox control registers
+
+ reg-names:
+ items:
+ - const: data
+ - const: ctl
+
+ clocks:
+ items:
+ - description: main clock of the GPUEB MCU
+
+ interrupts:
+ items:
+ - description: fires when a new message is received
+
+ "#mbox-cells":
+ const: 1
+ description:
+ The number of the mailbox channel.
+
+required:
+ - compatible
+ - reg
+ - reg-names
+ - clocks
+ - interrupts
+ - "#mbox-cells"
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/clock/mediatek,mt8196-clock.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/interrupt-controller/irq.h>
+
+ mailbox@4b09fd80 {
+ compatible = "mediatek,mt8196-gpueb-mbox";
+ reg = <0x4b09fd80 0x280>,
+ <0x4b170000 0x7c>;
+ reg-names = "data", "ctl";
+ clocks = <&topckgen CLK_TOP_MFG_EB>;
+ interrupts = <GIC_SPI 608 IRQ_TYPE_LEVEL_HIGH 0>;
+ #mbox-cells = <1>;
+ };

--
2.51.0