dt-bindings: serial: qcom,msm-uartdm: Vote for shared resources

Document power-domains, operating-points-v2 and interconnects to allow
making performance state votes for certain clock frequencies of the UART
DM controller. The interconnect path to DRAM is needed when UART DM is
used together with a DMA engine.

Voting for these shared resources is necessary to guarantee performance
with power management enabled. Otherwise these resources might run at
minimal performance state which is not sufficient for certain UART
baud rates.

Signed-off-by: Stephan Gerhold <stephan.gerhold@kernkonzept.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20231128-serial-msm-dvfs-v1-1-4f290d20a4be@kernkonzept.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/devicetree/bindings/serial/qcom,msm-uartdm.yaml

@@ -48,9 +48,17 @@ properties:
       - const: tx
       - const: rx
 
+  interconnects:
+    maxItems: 1
+
   interrupts:
     maxItems: 1
 
+  operating-points-v2: true
+
+  power-domains:
+    maxItems: 1
+
   qcom,rx-crci:
     $ref: /schemas/types.yaml#/definitions/uint32
     description:
@@ -99,7 +107,9 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/interconnect/qcom,msm8996.h>
     #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/power/qcom-rpmpd.h>
 
     serial@f991e000 {
         compatible = "qcom,msm-uartdm-v1.4", "qcom,msm-uartdm";
@@ -109,4 +119,7 @@ examples:
         clock-names = "core", "iface";
         dmas = <&dma0 0>, <&dma0 1>;
         dma-names = "tx", "rx";
+        power-domains = <&rpmpd MSM8996_VDDCX>;
+        operating-points-v2 = <&uart_opp_table>;
+        interconnects = <&pnoc MASTER_BLSP_1 &bimc SLAVE_EBI_CH0>;
     };