tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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 - Leonard Crestez <leonard.crestez@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: true
51
52required:
53 - reg
54 - compatible
55 - clocks
56 - clock-names
57
58additionalProperties: false
59
60examples:
61 - |
62 #include <dt-bindings/clock/imx8mm-clock.h>
63 ddrc: memory-controller@3d400000 {
64 compatible = "fsl,imx8mm-ddrc", "fsl,imx8m-ddrc";
65 reg = <0x3d400000 0x400000>;
66 clock-names = "core", "pll", "alt", "apb";
67 clocks = <&clk IMX8MM_CLK_DRAM_CORE>,
68 <&clk IMX8MM_DRAM_PLL>,
69 <&clk IMX8MM_CLK_DRAM_ALT>,
70 <&clk IMX8MM_CLK_DRAM_APB>;
71 operating-points-v2 = <&ddrc_opp_table>;
72 };