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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";
+ };
+
+...