dt-bindings: clock: qcom: Add CMN PLL clock controller for IPQ SoC

The CMN PLL controller provides clocks to networking hardware blocks
and to GCC on Qualcomm IPQ9574 SoC. It receives input clock from the
on-chip Wi-Fi, and produces output clocks at fixed rates. These output
rates are predetermined, and are unrelated to the input clock rate.
The primary purpose of CMN PLL is to supply clocks to the networking
hardware such as PPE (packet process engine), PCS and the externally
connected switch or PHY device. The CMN PLL block also outputs fixed
rate clocks to GCC, such as 24 MHZ as XO clock and 32 KHZ as sleep
clock supplied to GCC.

Signed-off-by: Luo Jie <quic_luoj@quicinc.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20250103-qcom_ipq_cmnpll-v8-1-c89fb4d4849d@quicinc.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>

Documentation/devicetree/bindings/clock/qcom,ipq9574-cmn-pll.yaml

@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/qcom,ipq9574-cmn-pll.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Qualcomm CMN PLL Clock Controller on IPQ SoC
+
+maintainers:
+  - Bjorn Andersson <andersson@kernel.org>
+  - Luo Jie <quic_luoj@quicinc.com>
+
+description:
+  The CMN (or common) PLL clock controller expects a reference
+  input clock. This reference clock is from the on-board Wi-Fi.
+  The CMN PLL supplies a number of fixed rate output clocks to
+  the devices providing networking functions and to GCC. These
+  networking hardware include PPE (packet process engine), PCS
+  and the externally connected switch or PHY devices. The CMN
+  PLL block also outputs fixed rate clocks to GCC. The PLL's
+  primary function is to enable fixed rate output clocks for
+  networking hardware functions used with the IPQ SoC.
+
+properties:
+  compatible:
+    enum:
+      - qcom,ipq9574-cmn-pll
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    items:
+      - description: The reference clock. The supported clock rates include
+          25000000, 31250000, 40000000, 48000000, 50000000 and 96000000 HZ.
+      - description: The AHB clock
+      - description: The SYS clock
+    description:
+      The reference clock is the source clock of CMN PLL, which is from the
+      Wi-Fi. The AHB and SYS clocks must be enabled to access CMN PLL
+      clock registers.
+
+  clock-names:
+    items:
+      - const: ref
+      - const: ahb
+      - const: sys
+
+  "#clock-cells":
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - clocks
+  - clock-names
+  - "#clock-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/qcom,ipq-cmn-pll.h>
+    #include <dt-bindings/clock/qcom,ipq9574-gcc.h>
+
+    cmn_pll: clock-controller@9b000 {
+        compatible = "qcom,ipq9574-cmn-pll";
+        reg = <0x0009b000 0x800>;
+        clocks = <&cmn_pll_ref_clk>,
+                 <&gcc GCC_CMN_12GPLL_AHB_CLK>,
+                 <&gcc GCC_CMN_12GPLL_SYS_CLK>;
+        clock-names = "ref", "ahb", "sys";
+        #clock-cells = <1>;
+        assigned-clocks = <&cmn_pll CMN_PLL_CLK>;
+        assigned-clock-rates-u64 = /bits/ 64 <12000000000>;
+    };
+...

include/dt-bindings/clock/qcom,ipq-cmn-pll.h

@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) */
+/*
+ * Copyright (c) 2024 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef _DT_BINDINGS_CLK_QCOM_IPQ_CMN_PLL_H
+#define _DT_BINDINGS_CLK_QCOM_IPQ_CMN_PLL_H
+
+/* CMN PLL core clock. */
+#define CMN_PLL_CLK			0
+
+/* The output clocks from CMN PLL of IPQ9574. */
+#define XO_24MHZ_CLK			1
+#define SLEEP_32KHZ_CLK			2
+#define PCS_31P25MHZ_CLK		3
+#define NSS_1200MHZ_CLK			4
+#define PPE_353MHZ_CLK			5
+#define ETH0_50MHZ_CLK			6
+#define ETH1_50MHZ_CLK			7
+#define ETH2_50MHZ_CLK			8
+#define ETH_25MHZ_CLK			9
+#endif