1 # SPDX-License-Identifier: (GPL-2.0-only OR BS 1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 %YAML 1.2 2 %YAML 1.2
3 --- 3 ---
4 $id: http://devicetree.org/schemas/clock/arm,s 4 $id: http://devicetree.org/schemas/clock/arm,syscon-icst.yaml#
5 $schema: http://devicetree.org/meta-schemas/co 5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6 6
7 title: ARM System Controller ICST Clocks 7 title: ARM System Controller ICST Clocks
8 8
9 maintainers: 9 maintainers:
10 - Linus Walleij <linusw@kernel.org> 10 - Linus Walleij <linusw@kernel.org>
11 11
12 description: | 12 description: |
13 The ICS525 and ICS307 oscillators are produc 13 The ICS525 and ICS307 oscillators are produced by Integrated
14 Devices Technology (IDT). ARM integrated the 14 Devices Technology (IDT). ARM integrated these oscillators deeply into their
15 reference designs by adding special control 15 reference designs by adding special control registers that manage such
16 oscillators to their system controllers. 16 oscillators to their system controllers.
17 17
18 The various ARM system controllers contain l 18 The various ARM system controllers contain logic to serialize and initialize
19 an ICST clock request after a write to the 3 19 an ICST clock request after a write to the 32 bit register at an offset
20 into the system controller. Furthermore, to 20 into the system controller. Furthermore, to even be able to alter one of
21 these frequencies, the system controller mus 21 these frequencies, the system controller must first be unlocked by
22 writing a special token to another offset in 22 writing a special token to another offset in the system controller.
23 23
24 Some ARM hardware contain special versions o 24 Some ARM hardware contain special versions of the serial interface that only
25 connects the low 8 bits of the VDW (missing 25 connects the low 8 bits of the VDW (missing one bit), hard-wires RDW to
26 different values and sometimes also hard-wir 26 different values and sometimes also hard-wires the output divider. They
27 therefore have special compatible strings as 27 therefore have special compatible strings as per this table (the OD value is
28 the value on the pins, not the resulting out 28 the value on the pins, not the resulting output divider).
29 29
30 In the core modules and logic tiles, the ICS 30 In the core modules and logic tiles, the ICST is a configurable clock fed
31 from a 24 MHz clock on the motherboard (usua 31 from a 24 MHz clock on the motherboard (usually the main crystal) used for
32 generating e.g. video clocks. It is located 32 generating e.g. video clocks. It is located on the core module and there is
33 only one of these. This clock node must be a 33 only one of these. This clock node must be a subnode of the core module.
34 34
35 Hardware variant RDW OD 35 Hardware variant RDW OD VDW
36 36
37 Integrator/AP 22 1 37 Integrator/AP 22 1 Bit 8 0, rest variable
38 integratorap-cm 38 integratorap-cm
39 39
40 Integrator/AP 46 3 40 Integrator/AP 46 3 Bit 8 0, rest variable
41 integratorap-sys 41 integratorap-sys
42 42
43 Integrator/AP 22 or 1 43 Integrator/AP 22 or 1 17 or (33 or 25 MHz)
44 integratorap-pci 14 1 44 integratorap-pci 14 1 14
45 45
46 Integrator/CP 22 variable 46 Integrator/CP 22 variable Bit 8 0, rest variable
47 integratorcp-cm-core 47 integratorcp-cm-core
48 48
49 Integrator/CP 22 variable 49 Integrator/CP 22 variable Bit 8 0, rest variable
50 integratorcp-cm-mem 50 integratorcp-cm-mem
51 51
52 The ICST oscillator must be provided inside 52 The ICST oscillator must be provided inside a system controller node.
53 53
54 properties: 54 properties:
55 "#clock-cells": 55 "#clock-cells":
56 const: 0 56 const: 0
57 57
58 compatible: 58 compatible:
59 enum: 59 enum:
60 - arm,syscon-icst525 60 - arm,syscon-icst525
61 - arm,syscon-icst307 61 - arm,syscon-icst307
62 - arm,syscon-icst525-integratorap-cm 62 - arm,syscon-icst525-integratorap-cm
63 - arm,syscon-icst525-integratorap-sys 63 - arm,syscon-icst525-integratorap-sys
64 - arm,syscon-icst525-integratorap-pci 64 - arm,syscon-icst525-integratorap-pci
65 - arm,syscon-icst525-integratorcp-cm-cor 65 - arm,syscon-icst525-integratorcp-cm-core
66 - arm,syscon-icst525-integratorcp-cm-mem 66 - arm,syscon-icst525-integratorcp-cm-mem
67 - arm,integrator-cm-auxosc 67 - arm,integrator-cm-auxosc
68 - arm,versatile-cm-auxosc 68 - arm,versatile-cm-auxosc
69 - arm,impd1-vco1 69 - arm,impd1-vco1
70 - arm,impd1-vco2 70 - arm,impd1-vco2
71 71
72 reg: 72 reg:
73 maxItems: 1 73 maxItems: 1
74 description: The VCO register 74 description: The VCO register
75 75
76 clocks: 76 clocks:
77 description: Parent clock for the ICST VCO 77 description: Parent clock for the ICST VCO
78 maxItems: 1 78 maxItems: 1
79 79
80 clock-output-names: 80 clock-output-names:
81 maxItems: 1 81 maxItems: 1
82 82
83 lock-offset: 83 lock-offset:
84 $ref: /schemas/types.yaml#/definitions/uin 84 $ref: /schemas/types.yaml#/definitions/uint32
85 description: Offset to the unlocking regis 85 description: Offset to the unlocking register for the oscillator
86 86
87 vco-offset: 87 vco-offset:
88 $ref: /schemas/types.yaml#/definitions/uin 88 $ref: /schemas/types.yaml#/definitions/uint32
89 description: Offset to the VCO register fo 89 description: Offset to the VCO register for the oscillator
90 deprecated: true 90 deprecated: true
91 91
92 required: 92 required:
93 - "#clock-cells" 93 - "#clock-cells"
94 - compatible 94 - compatible
95 - clocks 95 - clocks
96 96
97 additionalProperties: false 97 additionalProperties: false
98 98
99 examples: 99 examples:
100 - | 100 - |
101 vco1: clock { 101 vco1: clock {
102 compatible = "arm,impd1-vco1"; 102 compatible = "arm,impd1-vco1";
103 #clock-cells = <0>; 103 #clock-cells = <0>;
104 lock-offset = <0x08>; 104 lock-offset = <0x08>;
105 vco-offset = <0x00>; 105 vco-offset = <0x00>;
106 clocks = <&sysclk>; 106 clocks = <&sysclk>;
107 clock-output-names = "IM-PD1-VCO1"; 107 clock-output-names = "IM-PD1-VCO1";
108 }; 108 };
109 109
110 ... 110 ...
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