xref: /freebsd/sys/contrib/device-tree/Bindings/clock/st,stm32mp1-rcc.yaml (revision b077aed33b7b6aefca7b17ddb250cf521f938613) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/clock/st,stm32mp1-rcc.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: Reset Clock Controller Binding
8
9maintainers:
10  - Gabriel Fernandez <gabriel.fernandez@foss.st.com>
11
12description: |
13  The RCC IP is both a reset and a clock controller.
14  RCC makes also power management (resume/supend and wakeup interrupt).
15  Please also refer to reset.txt for common reset controller binding usage.
16
17  This binding uses common clock bindings
18  Documentation/devicetree/bindings/clock/clock-bindings.txt
19
20  Specifying clocks
21  =================
22
23  All available clocks are defined as preprocessor macros in
24  dt-bindings/clock/stm32mp1-clks.h header and can be used in device
25  tree sources.
26
27  Specifying softreset control of devices
28  =======================================
29
30  Device nodes should specify the reset channel required in their "resets"
31  property, containing a phandle to the reset device node and an index specifying
32  which channel to use.
33  The index is the bit number within the RCC registers bank, starting from RCC
34  base address.
35  It is calculated as: index = register_offset / 4 * 32 + bit_offset.
36  Where bit_offset is the bit offset within the register.
37
38  For example on STM32MP1, for LTDC reset:
39     ltdc = APB4_RSTSETR_offset / 4 * 32 + LTDC_bit_offset
40          = 0x180 / 4 * 32 + 0 = 3072
41
42  The list of valid indices for STM32MP1 is available in:
43  include/dt-bindings/reset-controller/stm32mp1-resets.h
44  include/dt-bindings/reset-controller/stm32mp13-resets.h
45
46  This file implements defines like:
47  #define LTDC_R	3072
48
49properties:
50  "#clock-cells":
51    const: 1
52
53  "#reset-cells":
54    const: 1
55
56  compatible:
57    items:
58      - enum:
59          - st,stm32mp1-rcc-secure
60          - st,stm32mp1-rcc
61          - st,stm32mp13-rcc
62      - const: syscon
63  clocks: true
64  clock-names: true
65
66  reg:
67    maxItems: 1
68
69required:
70  - "#clock-cells"
71  - "#reset-cells"
72  - compatible
73  - reg
74
75if:
76  properties:
77    compatible:
78      contains:
79        enum:
80          - st,stm32mp1-rcc-secure
81          - st,stm32mp13-rcc
82then:
83  properties:
84    clocks:
85      description: Specifies oscillators.
86      maxItems: 5
87
88    clock-names:
89      items:
90        - const: hse
91        - const: hsi
92        - const: csi
93        - const: lse
94        - const: lsi
95  required:
96    - clocks
97    - clock-names
98else:
99  properties:
100    clocks:
101      description:
102        Specifies the external RX clock for ethernet MAC.
103      maxItems: 1
104
105    clock-names:
106      const: ETH_RX_CLK/ETH_REF_CLK
107
108additionalProperties: false
109
110examples:
111  - |
112    #include <dt-bindings/clock/stm32mp1-clks.h>
113    rcc: rcc@50000000 {
114        compatible = "st,stm32mp1-rcc-secure", "syscon";
115        reg = <0x50000000 0x1000>;
116        #clock-cells = <1>;
117        #reset-cells = <1>;
118        clock-names = "hse", "hsi", "csi", "lse", "lsi";
119        clocks = <&scmi_clk CK_SCMI_HSE>,
120                 <&scmi_clk CK_SCMI_HSI>,
121                 <&scmi_clk CK_SCMI_CSI>,
122                 <&scmi_clk CK_SCMI_LSE>,
123                 <&scmi_clk CK_SCMI_LSI>;
124    };
125...
126