# SPDX-License-Identifier: GPL-2.0 %YAML 1.2 --- $id: http://devicetree.org/schemas/memory-controllers/fsl/imx8m-ddrc.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: i.MX8M DDR Controller maintainers: - Peng Fan description: The DDRC block is integrated in i.MX8M for interfacing with DDR based memories. It supports switching between different frequencies at runtime but during this process RAM itself becomes briefly inaccessible so actual frequency switching is implemented by TF-A code which runs from a SRAM area. The Linux driver for the DDRC doesn't even map registers (they're included for the sake of "describing hardware"), it mostly just exposes firmware capabilities through standard Linux mechanism like devfreq and OPP tables. properties: compatible: items: - enum: - fsl,imx8mn-ddrc - fsl,imx8mm-ddrc - fsl,imx8mq-ddrc - const: fsl,imx8m-ddrc reg: maxItems: 1 description: Base address and size of DDRC CTL area. This is not currently mapped by the imx8m-ddrc driver. clocks: maxItems: 4 clock-names: items: - const: core - const: pll - const: alt - const: apb operating-points-v2: true opp-table: type: object required: - reg - compatible - clocks - clock-names additionalProperties: false examples: - | #include ddrc: memory-controller@3d400000 { compatible = "fsl,imx8mm-ddrc", "fsl,imx8m-ddrc"; reg = <0x3d400000 0x400000>; clock-names = "core", "pll", "alt", "apb"; clocks = <&clk IMX8MM_CLK_DRAM_CORE>, <&clk IMX8MM_DRAM_PLL>, <&clk IMX8MM_CLK_DRAM_ALT>, <&clk IMX8MM_CLK_DRAM_APB>; operating-points-v2 = <&ddrc_opp_table>; };