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# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/clock/google,gs101-clock.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#
title: Google GS101 SoC clock controller
maintainers:
- Peter Griffin <peter.griffin@linaro.org>
description: |
Google GS101 clock controller is comprised of several CMU units, generating
clocks for different domains. Those CMU units are modeled as separate device
tree nodes, and might depend on each other. The root clock in that clock tree
is OSCCLK (24.576 MHz). That external clock must be defined as a fixed-rate
clock in dts.
CMU_TOP is a top-level CMU, where all base clocks are prepared using PLLs and
dividers; all other leaf clocks (other CMUs) are usually derived from CMU_TOP.
Each clock is assigned an identifier and client nodes can use this identifier
to specify the clock which they consume. All clocks available for usage
in clock consumer nodes are defined as preprocessor macros in
'dt-bindings/clock/gs101.h' header.
properties:
compatible:
enum:
- google,gs101-cmu-top
- google,gs101-cmu-apm
- google,gs101-cmu-misc
clocks:
minItems: 1
maxItems: 2
clock-names:
minItems: 1
maxItems: 2
"#clock-cells":
const: 1
reg:
maxItems: 1
required:
- compatible
- "#clock-cells"
- clocks
- clock-names
- reg
allOf:
- if:
properties:
compatible:
contains:
enum:
- google,gs101-cmu-top
- google,gs101-cmu-apm
then:
properties:
clocks:
items:
- description: External reference clock (24.576 MHz)
clock-names:
items:
- const: oscclk
- if:
properties:
compatible:
contains:
const: google,gs101-cmu-misc
then:
properties:
clocks:
items:
- description: Misc bus clock (from CMU_TOP)
- description: Misc sss clock (from CMU_TOP)
clock-names:
items:
- const: bus
- const: sss
additionalProperties: false
examples:
# Clock controller node for CMU_TOP
- |
#include <dt-bindings/clock/google,gs101.h>
cmu_top: clock-controller@1e080000 {
compatible = "google,gs101-cmu-top";
reg = <0x1e080000 0x8000>;
#clock-cells = <1>;
clocks = <&ext_24_5m>;
clock-names = "oscclk";
};
...
|
