From 5d6298f25a0db3de87f5209eb7b0fa97d4eae280 Mon Sep 17 00:00:00 2001 From: Sam Protsenko Date: Fri, 8 Oct 2021 18:43:51 +0300 Subject: [PATCH] dt-bindings: clock: Document Exynos850 CMU bindings Provide dt-schema documentation for Exynos850 SoC clock controller. Signed-off-by: Sam Protsenko Reviewed-by: Krzysztof Kozlowski Acked-by: Chanwoo Choi Link: https://lore.kernel.org/r/20211008154352.19519-5-semen.protsenko@linaro.org Signed-off-by: Sylwester Nawrocki --- .../bindings/clock/samsung,exynos850-clock.yaml | 185 +++++++++++++++++++++ 1 file changed, 185 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml diff --git a/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml b/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml new file mode 100644 index 0000000..7f8c91a --- /dev/null +++ b/Documentation/devicetree/bindings/clock/samsung,exynos850-clock.yaml @@ -0,0 +1,185 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/clock/samsung,exynos850-clock.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Samsung Exynos850 SoC clock controller + +maintainers: + - Sam Protsenko + - Chanwoo Choi + - Krzysztof Kozlowski + - Sylwester Nawrocki + - Tomasz Figa + +description: | + Exynos850 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. Root clocks in that clock tree are + two external clocks:: OSCCLK (26 MHz) and RTCCLK (32768 Hz). Those external + clocks must be defined as fixed-rate clocks 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/exynos850.h' header. + +properties: + compatible: + enum: + - samsung,exynos850-cmu-top + - samsung,exynos850-cmu-core + - samsung,exynos850-cmu-dpu + - samsung,exynos850-cmu-hsi + - samsung,exynos850-cmu-peri + + clocks: + minItems: 1 + maxItems: 5 + + clock-names: + minItems: 1 + maxItems: 5 + + "#clock-cells": + const: 1 + + reg: + maxItems: 1 + +allOf: + - if: + properties: + compatible: + contains: + const: samsung,exynos850-cmu-top + + then: + properties: + clocks: + items: + - description: External reference clock (26 MHz) + + clock-names: + items: + - const: oscclk + + - if: + properties: + compatible: + contains: + const: samsung,exynos850-cmu-core + + then: + properties: + clocks: + items: + - description: External reference clock (26 MHz) + - description: CMU_CORE bus clock (from CMU_TOP) + - description: CCI clock (from CMU_TOP) + - description: eMMC clock (from CMU_TOP) + - description: SSS clock (from CMU_TOP) + + clock-names: + items: + - const: oscclk + - const: dout_core_bus + - const: dout_core_cci + - const: dout_core_mmc_embd + - const: dout_core_sss + + - if: + properties: + compatible: + contains: + const: samsung,exynos850-cmu-dpu + + then: + properties: + clocks: + items: + - description: External reference clock (26 MHz) + - description: DPU clock (from CMU_TOP) + + clock-names: + items: + - const: oscclk + - const: dout_dpu + + - if: + properties: + compatible: + contains: + const: samsung,exynos850-cmu-hsi + + then: + properties: + clocks: + items: + - description: External reference clock (26 MHz) + - description: External RTC clock (32768 Hz) + - description: CMU_HSI bus clock (from CMU_TOP) + - description: SD card clock (from CMU_TOP) + - description: "USB 2.0 DRD clock (from CMU_TOP)" + + clock-names: + items: + - const: oscclk + - const: rtcclk + - const: dout_hsi_bus + - const: dout_hsi_mmc_card + - const: dout_hsi_usb20drd + + - if: + properties: + compatible: + contains: + const: samsung,exynos850-cmu-peri + + then: + properties: + clocks: + items: + - description: External reference clock (26 MHz) + - description: CMU_PERI bus clock (from CMU_TOP) + - description: UART clock (from CMU_TOP) + - description: Parent clock for HSI2C and SPI (from CMU_TOP) + + clock-names: + items: + - const: oscclk + - const: dout_peri_bus + - const: dout_peri_uart + - const: dout_peri_ip + +required: + - compatible + - "#clock-cells" + - clocks + - clock-names + - reg + +additionalProperties: false + +examples: + # Clock controller node for CMU_PERI + - | + #include + + cmu_peri: clock-controller@10030000 { + compatible = "samsung,exynos850-cmu-peri"; + reg = <0x10030000 0x8000>; + #clock-cells = <1>; + + clocks = <&oscclk>, <&cmu_top CLK_DOUT_PERI_BUS>, + <&cmu_top CLK_DOUT_PERI_UART>, + <&cmu_top CLK_DOUT_PERI_IP>; + clock-names = "oscclk", "dout_peri_bus", + "dout_peri_uart", "dout_peri_ip"; + }; + +... -- 2.7.4