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1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/net/ti,k3-am654-cpts.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: The TI AM654x/J721E Common Platform Time Sync (CPTS) module Device Tree Bindings
8
9maintainers:
10 - Grygorii Strashko <grygorii.strashko@ti.com>
11 - Sekhar Nori <nsekhar@ti.com>
12
13description: |+
14 The TI AM654x/J721E CPTS module is used to facilitate host control of time
15 sync operations.
16 Main features of CPTS module are
17 - selection of multiple external clock sources
18 - Software control of time sync events via interrupt or polling
19 - 64-bit timestamp mode in ns with PPM and nudge adjustment.
20 - hardware timestamp push inputs (HWx_TS_PUSH)
21 - timestamp counter compare output (TS_COMP)
22 - timestamp counter bit output (TS_SYNC)
23 - periodic Generator function outputs (TS_GENFx)
24 - Ethernet Enhanced Scheduled Traffic Operations (CPTS_ESTFn) (TSN)
25 - external hardware timestamp push inputs (HWx_TS_PUSH) timestamping
26
27 Depending on integration it enables compliance with the IEEE 1588-2008
28 standard for a precision clock synchronization protocol, Ethernet Enhanced
29 Scheduled Traffic Operations (CPTS_ESTFn) and PCIe Subsystem Precision Time
30 Measurement (PTM).
31
32 TI AM654x/J721E SoCs has several similar CPTS modules integrated into the
33 different parts of the system which could be synchronized with each other
34 - Main CPTS
35 - MCU CPSW CPTS with IEEE 1588-2008 support
36 - PCIe subsystem CPTS for PTM support
37
38 Depending on CPTS module integration and when CPTS is integral part of
39 another module (MCU CPSW for example) "compatible" and "reg" can
40 be omitted - parent module is fully responsible for CPTS enabling and
41 configuration.
42
43properties:
44 $nodename:
45 pattern: "^cpts@[0-9a-f]+$"
46
47 compatible:
48 oneOf:
49 - const: ti,am65-cpts
50 - const: ti,j721e-cpts
51
52 reg:
53 maxItems: 1
54 description:
55 The physical base address and size of CPTS IO range
56
57 reg-names:
58 items:
59 - const: cpts
60
61 clocks:
62 description: CPTS reference clock
63
64 clock-names:
65 items:
66 - const: cpts
67
68 interrupts:
69 items:
70 - description: CPTS events interrupt
71
72 interrupt-names:
73 items:
74 - const: cpts
75
76 ti,cpts-ext-ts-inputs:
77 $ref: /schemas/types.yaml#/definitions/uint32
78 maximum: 8
79 description:
80 Number of hardware timestamp push inputs (HWx_TS_PUSH)
81
82 ti,cpts-periodic-outputs:
83 $ref: /schemas/types.yaml#/definitions/uint32
84 maximum: 8
85 description:
86 Number of timestamp Generator function outputs (TS_GENFx)
87
88 refclk-mux:
89 type: object
90 description: CPTS reference clock multiplexer clock
91 properties:
92 '#clock-cells':
93 const: 0
94
95 clocks:
96 maxItems: 8
97
98 assigned-clocks:
99 maxItems: 1
100
101 assigned-clocks-parents:
102 maxItems: 1
103
104 required:
105 - clocks
106
107required:
108 - compatible
109 - reg
110 - clocks
111 - clock-names
112 - interrupts
113 - interrupt-names
114
115additionalProperties: false
116
117examples:
118 - |
119 #include <dt-bindings/interrupt-controller/irq.h>
120 #include <dt-bindings/interrupt-controller/arm-gic.h>
121
122 cpts@310d0000 {
123 compatible = "ti,am65-cpts";
124 reg = <0x310d0000 0x400>;
125 reg-names = "cpts";
126 clocks = <&main_cpts_mux>;
127 clock-names = "cpts";
128 interrupts-extended = <&k3_irq 163 0 IRQ_TYPE_LEVEL_HIGH>;
129 interrupt-names = "cpts";
130 ti,cpts-periodic-outputs = <6>;
131 ti,cpts-ext-ts-inputs = <8>;
132
133 main_cpts_mux: refclk-mux {
134 #clock-cells = <0>;
135 clocks = <&k3_clks 118 5>, <&k3_clks 118 11>,
136 <&k3_clks 157 91>, <&k3_clks 157 77>,
137 <&k3_clks 157 102>, <&k3_clks 157 80>,
138 <&k3_clks 120 3>, <&k3_clks 121 3>;
139 assigned-clocks = <&main_cpts_mux>;
140 assigned-clock-parents = <&k3_clks 118 11>;
141 };
142 };
143