xref: /linux/Documentation/devicetree/bindings/clock/st,stm32mp1-rcc.yaml (revision 3ea5eb68b9d624935108b5e696859304edfac202) 
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: STMicroelectronics STM32MP1 Reset Clock Controller
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
64  clocks:
65    minItems: 1
66    maxItems: 5
67
68  clock-names:
69    minItems: 1
70    maxItems: 5
71
72  reg:
73    maxItems: 1
74
75required:
76  - "#clock-cells"
77  - "#reset-cells"
78  - compatible
79  - reg
80
81if:
82  properties:
83    compatible:
84      contains:
85        enum:
86          - st,stm32mp1-rcc-secure
87          - st,stm32mp13-rcc
88then:
89  properties:
90    clocks:
91      description: Specifies oscillators.
92      maxItems: 5
93
94    clock-names:
95      items:
96        - const: hse
97        - const: hsi
98        - const: csi
99        - const: lse
100        - const: lsi
101  required:
102    - clocks
103    - clock-names
104else:
105  properties:
106    clocks:
107      description:
108        Specifies the external RX clock for ethernet MAC.
109      maxItems: 1
110
111    clock-names:
112      const: ETH_RX_CLK/ETH_REF_CLK
113
114additionalProperties: false
115
116examples:
117  - |
118    #include <dt-bindings/clock/stm32mp1-clks.h>
119    rcc: rcc@50000000 {
120        compatible = "st,stm32mp1-rcc-secure", "syscon";
121        reg = <0x50000000 0x1000>;
122        #clock-cells = <1>;
123        #reset-cells = <1>;
124        clock-names = "hse", "hsi", "csi", "lse", "lsi";
125        clocks = <&scmi_clk CK_SCMI_HSE>,
126                 <&scmi_clk CK_SCMI_HSI>,
127                 <&scmi_clk CK_SCMI_CSI>,
128                 <&scmi_clk CK_SCMI_LSE>,
129                 <&scmi_clk CK_SCMI_LSI>;
130    };
131...
132