summaryrefslogtreecommitdiffstats
path: root/dts/Bindings/mailbox/mtk-gce.txt
diff options
context:
space:
mode:
Diffstat (limited to 'dts/Bindings/mailbox/mtk-gce.txt')
-rw-r--r--dts/Bindings/mailbox/mtk-gce.txt57
1 files changed, 57 insertions, 0 deletions
diff --git a/dts/Bindings/mailbox/mtk-gce.txt b/dts/Bindings/mailbox/mtk-gce.txt
new file mode 100644
index 0000000..7d72b21
--- /dev/null
+++ b/dts/Bindings/mailbox/mtk-gce.txt
@@ -0,0 +1,57 @@
+MediaTek GCE
+===============
+
+The Global Command Engine (GCE) is used to help read/write registers with
+critical time limitation, such as updating display configuration during the
+vblank. The GCE can be used to implement the Command Queue (CMDQ) driver.
+
+CMDQ driver uses mailbox framework for communication. Please refer to
+mailbox.txt for generic information about mailbox device-tree bindings.
+
+Required properties:
+- compatible: Must be "mediatek,mt8173-gce"
+- reg: Address range of the GCE unit
+- interrupts: The interrupt signal from the GCE block
+- clock: Clocks according to the common clock binding
+- clock-names: Must be "gce" to stand for GCE clock
+- #mbox-cells: Should be 3.
+ <&phandle channel priority atomic_exec>
+ phandle: Label name of a gce node.
+ channel: Channel of mailbox. Be equal to the thread id of GCE.
+ priority: Priority of GCE thread.
+ atomic_exec: GCE processing continuous packets of commands in atomic
+ way.
+
+Required properties for a client device:
+- mboxes: Client use mailbox to communicate with GCE, it should have this
+ property and list of phandle, mailbox specifiers.
+- mediatek,gce-subsys: u32, specify the sub-system id which is corresponding
+ to the register address.
+
+Some vaules of properties are defined in 'dt-bindings/gce/mt8173-gce.h'. Such as
+sub-system ids, thread priority, event ids.
+
+Example:
+
+ gce: gce@10212000 {
+ compatible = "mediatek,mt8173-gce";
+ reg = <0 0x10212000 0 0x1000>;
+ interrupts = <GIC_SPI 135 IRQ_TYPE_LEVEL_LOW>;
+ clocks = <&infracfg CLK_INFRA_GCE>;
+ clock-names = "gce";
+ thread-num = CMDQ_THR_MAX_COUNT;
+ #mbox-cells = <3>;
+ };
+
+Example for a client device:
+
+ mmsys: clock-controller@14000000 {
+ compatible = "mediatek,mt8173-mmsys";
+ mboxes = <&gce 0 CMDQ_THR_PRIO_LOWEST 1>,
+ <&gce 1 CMDQ_THR_PRIO_LOWEST 1>;
+ mediatek,gce-subsys = <SUBSYS_1400XXXX>;
+ mutex-event-eof = <CMDQ_EVENT_MUTEX0_STREAM_EOF
+ CMDQ_EVENT_MUTEX1_STREAM_EOF>;
+
+ ...
+ };