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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/clock/arm,syscon-icst.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ARM System Controller ICST Clocks
+
+maintainers:
+  - Linus Walleij <linusw@kernel.org>
+
+description: |
+  The ICS525 and ICS307 oscillators are produced by Integrated
+  Devices Technology (IDT). ARM integrated these oscillators deeply into their
+  reference designs by adding special control registers that manage such
+  oscillators to their system controllers.
+
+  The various ARM system controllers contain logic to serialize and initialize
+  an ICST clock request after a write to the 32 bit register at an offset
+  into the system controller. Furthermore, to even be able to alter one of
+  these frequencies, the system controller must first be unlocked by
+  writing a special token to another offset in the system controller.
+
+  Some ARM hardware contain special versions of the serial interface that only
+  connects the low 8 bits of the VDW (missing one bit), hard-wires RDW to
+  different values and sometimes also hard-wires the output divider. They
+  therefore have special compatible strings as per this table (the OD value is
+  the value on the pins, not the resulting output divider).
+
+  In the core modules and logic tiles, the ICST is a configurable clock fed
+  from a 24 MHz clock on the motherboard (usually the main crystal) used for
+  generating e.g. video clocks. It is located on the core module and there is
+  only one of these. This clock node must be a subnode of the core module.
+
+  Hardware variant         RDW     OD          VDW
+
+  Integrator/AP            22      1           Bit 8 0, rest variable
+  integratorap-cm
+
+  Integrator/AP            46      3           Bit 8 0, rest variable
+  integratorap-sys
+
+  Integrator/AP            22 or   1           17 or (33 or 25 MHz)
+  integratorap-pci         14      1           14
+
+  Integrator/CP            22      variable    Bit 8 0, rest variable
+  integratorcp-cm-core
+
+  Integrator/CP            22      variable    Bit 8 0, rest variable
+  integratorcp-cm-mem
+
+  The ICST oscillator must be provided inside a system controller node.
+
+properties:
+  "#clock-cells":
+    const: 0
+
+  compatible:
+    enum:
+      - arm,syscon-icst525
+      - arm,syscon-icst307
+      - arm,syscon-icst525-integratorap-cm
+      - arm,syscon-icst525-integratorap-sys
+      - arm,syscon-icst525-integratorap-pci
+      - arm,syscon-icst525-integratorcp-cm-core
+      - arm,syscon-icst525-integratorcp-cm-mem
+      - arm,integrator-cm-auxosc
+      - arm,versatile-cm-auxosc
+      - arm,impd-vco1
+      - arm,impd-vco2
+
+  clocks:
+    description: Parent clock for the ICST VCO
+    maxItems: 1
+
+  clock-output-names:
+    maxItems: 1
+
+  lock-offset:
+    $ref: '/schemas/types.yaml#/definitions/uint32'
+    description: Offset to the unlocking register for the oscillator
+
+  vco-offset:
+    $ref: '/schemas/types.yaml#/definitions/uint32'
+    description: Offset to the VCO register for the oscillator
+
+required:
+  - "#clock-cells"
+  - compatible
+  - clocks
+
+additionalProperties: false
+
+examples:
+  - |
+    vco1: clock {
+      compatible = "arm,impd1-vco1";
+      #clock-cells = <0>;
+      lock-offset = <0x08>;
+      vco-offset = <0x00>;
+      clocks = <&sysclk>;
+      clock-output-names = "IM-PD1-VCO1";
+    };
+
+...