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>

diff --git a/Documentation/devicetree/bindings/serial/qcom,msm-uartdm.yaml b/Documentation/devicetree/bindings/serial/qcom,msm-uartdm.yaml
index ee52bf8e8917d482253edefe0ea2260a022bc461..e0fa363ad7e2e5cf17126f9bf38fd3e1f183b6d8 100644 (file)
--- a/Documentation/devicetree/bindings/serial/qcom,msm-uartdm.yaml
+++ b/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>;
     };