xref: /linux/Documentation/devicetree/bindings/memory-controllers/fsl/imx8m-ddrc.yaml (revision 4f2c0a4acffbec01079c28f839422e64ddeff004) 
1# SPDX-License-Identifier: GPL-2.0
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/memory-controllers/fsl/imx8m-ddrc.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: i.MX8M DDR Controller
8
9maintainers:
10  - Peng Fan <peng.fan@nxp.com>
11
12description:
13  The DDRC block is integrated in i.MX8M for interfacing with DDR based
14  memories.
15
16  It supports switching between different frequencies at runtime but during
17  this process RAM itself becomes briefly inaccessible so actual frequency
18  switching is implemented by TF-A code which runs from a SRAM area.
19
20  The Linux driver for the DDRC doesn't even map registers (they're included
21  for the sake of "describing hardware"), it mostly just exposes firmware
22  capabilities through standard Linux mechanism like devfreq and OPP tables.
23
24properties:
25  compatible:
26    items:
27      - enum:
28          - fsl,imx8mn-ddrc
29          - fsl,imx8mm-ddrc
30          - fsl,imx8mq-ddrc
31      - const: fsl,imx8m-ddrc
32
33  reg:
34    maxItems: 1
35    description:
36      Base address and size of DDRC CTL area.
37      This is not currently mapped by the imx8m-ddrc driver.
38
39  clocks:
40    maxItems: 4
41
42  clock-names:
43    items:
44      - const: core
45      - const: pll
46      - const: alt
47      - const: apb
48
49  operating-points-v2: true
50  opp-table:
51    type: object
52
53required:
54  - reg
55  - compatible
56  - clocks
57  - clock-names
58
59additionalProperties: false
60
61examples:
62  - |
63    #include <dt-bindings/clock/imx8mm-clock.h>
64    ddrc: memory-controller@3d400000 {
65        compatible = "fsl,imx8mm-ddrc", "fsl,imx8m-ddrc";
66        reg = <0x3d400000 0x400000>;
67        clock-names = "core", "pll", "alt", "apb";
68        clocks = <&clk IMX8MM_CLK_DRAM_CORE>,
69                 <&clk IMX8MM_DRAM_PLL>,
70                 <&clk IMX8MM_CLK_DRAM_ALT>,
71                 <&clk IMX8MM_CLK_DRAM_APB>;
72        operating-points-v2 = <&ddrc_opp_table>;
73    };
74