xref: /freebsd/sys/contrib/device-tree/Bindings/clock/st,stm32mp1-rcc.yaml (revision 924226fba12cc9a228c73b956e1b7fa24c60b055) 
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@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
45  This file implements defines like:
46  #define LTDC_R	3072
47
48properties:
49  "#clock-cells":
50    const: 1
51
52  "#reset-cells":
53    const: 1
54
55  compatible:
56    items:
57      - const: st,stm32mp1-rcc
58      - const: syscon
59
60  reg:
61    maxItems: 1
62
63required:
64  - "#clock-cells"
65  - "#reset-cells"
66  - compatible
67  - reg
68
69additionalProperties: false
70
71examples:
72  - |
73    rcc: rcc@50000000 {
74        compatible = "st,stm32mp1-rcc", "syscon";
75        reg = <0x50000000 0x1000>;
76        #clock-cells = <1>;
77        #reset-cells = <1>;
78    };
79...
80