# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/clock/samsung,exynos990-clock.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: Samsung Exynos990 SoC clock controller maintainers: - Igor Belwon - Chanwoo Choi - Krzysztof Kozlowski description: | Exynos990 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 root tree is an external clock: OSCCLK (26 MHz). This 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 clocks of function blocks (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 'include/dt-bindings/clock/samsung,exynos990.h' header. properties: compatible: enum: - samsung,exynos990-cmu-hsi0 - samsung,exynos990-cmu-top clocks: minItems: 1 maxItems: 5 clock-names: minItems: 1 maxItems: 5 "#clock-cells": const: 1 reg: maxItems: 1 required: - compatible - clocks - clock-names - "#clock-cells" - reg allOf: - if: properties: compatible: contains: const: samsung,exynos990-cmu-hsi0 then: properties: clocks: items: - description: External reference clock (26 MHz) - description: CMU_HSI0 BUS clock (from CMU_TOP) - description: CMU_HSI0 USB31DRD clock (from CMU_TOP) - description: CMU_HSI0 USBDP_DEBUG clock (from CMU_TOP) - description: CMU_HSI0 DPGTC clock (from CMU_TOP) clock-names: items: - const: oscclk - const: bus - const: usb31drd - const: usbdp_debug - const: dpgtc - if: properties: compatible: contains: const: samsung,exynos990-cmu-top then: properties: clocks: items: - description: External reference clock (26 MHz) clock-names: items: - const: oscclk additionalProperties: false examples: - | #include cmu_hsi0: clock-controller@10a00000 { compatible = "samsung,exynos990-cmu-hsi0"; reg = <0x10a00000 0x8000>; #clock-cells = <1>; clocks = <&oscclk>, <&cmu_top CLK_DOUT_CMU_HSI0_BUS>, <&cmu_top CLK_DOUT_CMU_HSI0_USB31DRD>, <&cmu_top CLK_DOUT_CMU_HSI0_USBDP_DEBUG>, <&cmu_top CLK_DOUT_CMU_HSI0_DPGTC>; clock-names = "oscclk", "bus", "usb31drd", "usbdp_debug", "dpgtc"; }; ...