1 # SPDX-License-Identifier: (GPL-2.0-only OR BS
2 %YAML 1.2
3 ---
4 $id: http://devicetree.org/schemas/soc/ti/wkup
5 $schema: http://devicetree.org/meta-schemas/co
6
7 title: Wakeup M3 IPC device
8
9 maintainers:
10 - Dave Gerlach <d-gerlach@ti.com>
11 - Drew Fustini <dfustini@baylibre.com>
12
13 description: |+
14 The TI AM33xx and AM43xx family of devices u
15 (commonly referred to as Wakeup M3 or CM3) t
16 that cannot be controlled from the MPU, like
17 C-states for CPU Idle. Once the wkup_m3_ipc
18 to boot the wkup_m3, it handles communicatio
19 present in the SoC's control module and a ma
20 API to allow the SoC PM code to execute spec
21
22 Wkup M3 Device Node
23 ====================
24 A wkup_m3_ipc device node is used to represe
25 SoC.
26
27 Support for VTT Toggle with GPIO pin
28 ====================================
29 On some boards like the AM335x EVM-SK and th
30 connected to the enable pin on the DDR VTT r
31 regulator to be disabled upon suspend and en
32 that the GPIO pin must be part of the GPIO0
33 is in the wakeup power domain.
34
35 Support for IO Isolation
36 ========================
37 On AM437x SoCs, certain pins can be forced i
38 isolation is activated. Those pins have pad
39 'CTRL_CONF_' that contain DS0 (e.g. deep sle
40 override the pin's existing bias (pull-up/pu
41 IO isolation is active.
42
43 Support for I2C PMIC Voltage Scaling
44 ====================================
45 It is possible to pass the name of a binary
46 The binary data is the I2C sequences for the
47 during low power mode entry.
48
49 properties:
50 compatible:
51 enum:
52 - ti,am3352-wkup-m3-ipc # for AM33xx SoC
53 - ti,am4372-wkup-m3-ipc # for AM43xx SoC
54
55 reg:
56 description:
57 The IPC register address space to commun
58 maxItems: 1
59
60 interrupts:
61 description: wkup_m3 interrupt that signal
62 maxItems: 1
63
64 ti,rproc:
65 $ref: /schemas/types.yaml#/definitions/pha
66 description:
67 phandle to the wkup_m3 rproc node so the
68
69 mboxes:
70 description:
71 phandles used by IPC framework to get co
72 channel for communication. Must point to
73 mbox_wkupm3 child node.
74 maxItems: 1
75
76 firmware-name:
77 description:
78 Name of binary file with I2C sequences f
79
80 ti,vtt-gpio-pin:
81 $ref: /schemas/types.yaml#/definitions/uin
82 description: GPIO pin connected to enable
83
84 ti,set-io-isolation:
85 type: boolean
86 description:
87 If this property is present, then the wk
88 the CM3 firmware to activate IO isolatio
89 This can be leveraged by a board design
90 into a low power state.
91
92 allOf:
93 - if:
94 properties:
95 compatible:
96 not:
97 contains:
98 const: ti,am4372-wkup-m3-ipc
99 then:
100 properties:
101 ti,set-io-isolation: false
102
103 required:
104 - compatible
105 - reg
106 - interrupts
107 - ti,rproc
108 - mboxes
109
110 additionalProperties: false
111
112 examples:
113 - |
114 /* Example for AM335x SoC */
115 soc {
116 #address-cells = <1>;
117 #size-cells = <1>;
118
119 am335x_mailbox: mailbox {
120 #mbox-cells = <1>;
121 };
122
123 wkup_m3_ipc@1324 {
124 compatible = "ti,am3352-wkup-m3-ipc
125 reg = <0x1324 0x24>;
126 interrupts = <78>;
127 ti,rproc = <&wkup_m3>;
128 mboxes = <&am335x_mailbox &mbox_wku
129 ti,vtt-gpio-pin = <7>;
130 firmware-name = "am335x-evm-scale-d
131 };
132 };
133
134 - |
135 /*
136 * Example for AM473x SoC:
137 * On the AM437x-GP-EVM board, gpio5_7 is
138 * regulator. The 'ddr_vtt_toggle_default'
139 * for pull-up during normal system operat
140 * state of the pin is configured for pull
141 * will be disabled to save power when IO
142 * this method is an alternative to using
143 */
144 #include <dt-bindings/pinctrl/am43xx.h>
145 soc {
146 #address-cells = <1>;
147 #size-cells = <1>;
148
149 am437x_mailbox: mailbox {
150 #mbox-cells = <1>;
151 };
152
153 am43xx_pinmux {
154 pinctrl-names = "default";
155 pinctrl-0 = <&ddr3_vtt_toggle_defa
156
157 ddr3_vtt_toggle_default: ddr_vtt_t
158 pinctrl-single,pins = <
159 0x25C (DS0_PULL_UP_DOWN_EN
160 >;
161 };
162 };
163
164 wkup_m3_ipc@1324 {
165 compatible = "ti,am4372-wkup-m3-ipc
166 reg = <0x1324 0x24>;
167 interrupts = <78>;
168 ti,rproc = <&wkup_m3>;
169 mboxes = <&am437x_mailbox &mbox_wku
170 ti,set-io-isolation;
171 firmware-name = "am43x-evm-scale-da
172 };
173 };
174
175 ...
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