1NXP i.MX System Controller Firmware (SCFW)
2--------------------------------------------------------------------
3
4The System Controller Firmware (SCFW) is a low-level system function
5which runs on a dedicated Cortex-M core to provide power, clock, and
6resource management. It exists on some i.MX8 processors. e.g. i.MX8QM
7(QM, QP), and i.MX8QX (QXP, DX).
8
9The AP communicates with the SC using a multi-ported MU module found
10in the LSIO subsystem. The current definition of this MU module provides
115 remote AP connections to the SC to support up to 5 execution environments
12(TZ, HV, standard Linux, etc.). The SC side of this MU module interfaces
13with the LSIO DSC IP bus. The SC firmware will communicate with this MU
14using the MSI bus.
15
16System Controller Device Node:
17============================================================
18
19The scu node with the following properties shall be under the /firmware/ node.
20
21Required properties:
22-------------------
23- compatible:	should be "fsl,imx-scu".
24- mbox-names:	should include "tx0", "tx1", "tx2", "tx3",
25			       "rx0", "rx1", "rx2", "rx3";
26		include "gip3" if want to support general MU interrupt.
27- mboxes:	List of phandle of 4 MU channels for tx, 4 MU channels for
28		rx, and 1 optional MU channel for general interrupt.
29		All MU channels must be in the same MU instance.
30		Cross instances are not allowed. The MU instance can only
31		be one of LSIO MU0~M4 for imx8qxp and imx8qm. Users need
32		to make sure use the one which is not conflict with other
33		execution environments. e.g. ATF.
34		Note:
35		Channel 0 must be "tx0" or "rx0".
36		Channel 1 must be "tx1" or "rx1".
37		Channel 2 must be "tx2" or "rx2".
38		Channel 3 must be "tx3" or "rx3".
39		General interrupt rx channel must be "gip3".
40		e.g.
41		mboxes = <&lsio_mu1 0 0
42			  &lsio_mu1 0 1
43			  &lsio_mu1 0 2
44			  &lsio_mu1 0 3
45			  &lsio_mu1 1 0
46			  &lsio_mu1 1 1
47			  &lsio_mu1 1 2
48			  &lsio_mu1 1 3
49			  &lsio_mu1 3 3>;
50		See Documentation/devicetree/bindings/mailbox/fsl,mu.yaml
51		for detailed mailbox binding.
52
53Note: Each mu which supports general interrupt should have an alias correctly
54numbered in "aliases" node.
55e.g.
56aliases {
57	mu1 = &lsio_mu1;
58};
59
60i.MX SCU Client Device Node:
61============================================================
62
63Client nodes are maintained as children of the relevant IMX-SCU device node.
64
65Power domain bindings based on SCU Message Protocol
66------------------------------------------------------------
67
68This binding for the SCU power domain providers uses the generic power
69domain binding[2].
70
71Required properties:
72- compatible:		Should be one of:
73			  "fsl,imx8qm-scu-pd",
74			  "fsl,imx8qxp-scu-pd"
75			followed by "fsl,scu-pd"
76
77- #power-domain-cells:	Must be 1. Contains the Resource ID used by
78			SCU commands.
79			See detailed Resource ID list from:
80			include/dt-bindings/firmware/imx/rsrc.h
81
82Clock bindings based on SCU Message Protocol
83------------------------------------------------------------
84
85This binding uses the common clock binding[1].
86
87Required properties:
88- compatible:		Should be one of:
89			  "fsl,imx8dxl-clk"
90			  "fsl,imx8qm-clk"
91			  "fsl,imx8qxp-clk"
92			followed by "fsl,scu-clk"
93- #clock-cells:		Should be 2.
94			Contains the Resource and Clock ID value.
95- clocks:		List of clock specifiers, must contain an entry for
96			each required entry in clock-names
97- clock-names:		Should include entries "xtal_32KHz", "xtal_24MHz"
98
99The clock consumer should specify the desired clock by having the clock
100ID in its "clocks" phandle cell.
101
102See the full list of clock IDs from:
103include/dt-bindings/clock/imx8qxp-clock.h
104
105Pinctrl bindings based on SCU Message Protocol
106------------------------------------------------------------
107
108This binding uses the i.MX common pinctrl binding[3].
109
110Required properties:
111- compatible:		Should be one of:
112			"fsl,imx8qm-iomuxc",
113			"fsl,imx8qxp-iomuxc",
114			"fsl,imx8dxl-iomuxc".
115
116Required properties for Pinctrl sub nodes:
117- fsl,pins:		Each entry consists of 3 integers which represents
118			the mux and config setting for one pin. The first 2
119			integers <pin_id mux_mode> are specified using a
120			PIN_FUNC_ID macro, which can be found in
121			<dt-bindings/pinctrl/pads-imx8qm.h>,
122			<dt-bindings/pinctrl/pads-imx8qxp.h>,
123			<dt-bindings/pinctrl/pads-imx8dxl.h>.
124			The last integer CONFIG is the pad setting value like
125			pull-up on this pin.
126
127			Please refer to i.MX8QXP Reference Manual for detailed
128			CONFIG settings.
129
130[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
131[2] Documentation/devicetree/bindings/power/power-domain.yaml
132[3] Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt
133
134RTC bindings based on SCU Message Protocol
135------------------------------------------------------------
136
137Required properties:
138- compatible: should be "fsl,imx8qxp-sc-rtc";
139
140OCOTP bindings based on SCU Message Protocol
141------------------------------------------------------------
142Required properties:
143- compatible:		Should be one of:
144			"fsl,imx8qm-scu-ocotp",
145			"fsl,imx8qxp-scu-ocotp".
146- #address-cells:	Must be 1. Contains byte index
147- #size-cells:		Must be 1. Contains byte length
148
149Optional Child nodes:
150
151- Data cells of ocotp:
152  Detailed bindings are described in bindings/nvmem/nvmem.txt
153
154Watchdog bindings based on SCU Message Protocol
155------------------------------------------------------------
156
157Required properties:
158- compatible: should be:
159              "fsl,imx8qxp-sc-wdt"
160              followed by "fsl,imx-sc-wdt";
161Optional properties:
162- timeout-sec: contains the watchdog timeout in seconds.
163
164SCU key bindings based on SCU Message Protocol
165------------------------------------------------------------
166
167Required properties:
168- compatible: should be:
169              "fsl,imx8qxp-sc-key"
170              followed by "fsl,imx-sc-key";
171- linux,keycodes: See Documentation/devicetree/bindings/input/input.yaml
172
173Thermal bindings based on SCU Message Protocol
174------------------------------------------------------------
175
176Required properties:
177- compatible:			Should be :
178				  "fsl,imx8qxp-sc-thermal"
179				followed by "fsl,imx-sc-thermal";
180
181- #thermal-sensor-cells:	See Documentation/devicetree/bindings/thermal/thermal-sensor.yaml
182				for a description.
183
184Example (imx8qxp):
185-------------
186aliases {
187	mu1 = &lsio_mu1;
188};
189
190lsio_mu1: mailbox@5d1c0000 {
191	...
192	#mbox-cells = <2>;
193};
194
195firmware {
196	scu {
197		compatible = "fsl,imx-scu";
198		mbox-names = "tx0", "tx1", "tx2", "tx3",
199			     "rx0", "rx1", "rx2", "rx3",
200			     "gip3";
201		mboxes = <&lsio_mu1 0 0
202			  &lsio_mu1 0 1
203			  &lsio_mu1 0 2
204			  &lsio_mu1 0 3
205			  &lsio_mu1 1 0
206			  &lsio_mu1 1 1
207			  &lsio_mu1 1 2
208			  &lsio_mu1 1 3
209			  &lsio_mu1 3 3>;
210
211		clk: clk {
212			compatible = "fsl,imx8qxp-clk", "fsl,scu-clk";
213			#clock-cells = <2>;
214		};
215
216		iomuxc {
217			compatible = "fsl,imx8qxp-iomuxc";
218
219			pinctrl_lpuart0: lpuart0grp {
220				fsl,pins = <
221					SC_P_UART0_RX_ADMA_UART0_RX	0x06000020
222					SC_P_UART0_TX_ADMA_UART0_TX	0x06000020
223				>;
224			};
225			...
226		};
227
228		ocotp: imx8qx-ocotp {
229			compatible = "fsl,imx8qxp-scu-ocotp";
230			#address-cells = <1>;
231			#size-cells = <1>;
232
233			fec_mac0: mac@2c4 {
234				reg = <0x2c4 8>;
235			};
236		};
237
238		pd: imx8qx-pd {
239			compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd";
240			#power-domain-cells = <1>;
241		};
242
243		rtc: rtc {
244			compatible = "fsl,imx8qxp-sc-rtc";
245		};
246
247		scu_key: scu-key {
248			compatible = "fsl,imx8qxp-sc-key", "fsl,imx-sc-key";
249			linux,keycodes = <KEY_POWER>;
250		};
251
252		watchdog {
253			compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
254			timeout-sec = <60>;
255		};
256
257		tsens: thermal-sensor {
258			compatible = "fsl,imx8qxp-sc-thermal", "fsl,imx-sc-thermal";
259			#thermal-sensor-cells = <1>;
260		};
261	};
262};
263
264serial@5a060000 {
265	...
266	pinctrl-names = "default";
267	pinctrl-0 = <&pinctrl_lpuart0>;
268	clocks = <&uart0_clk IMX_SC_R_UART_0 IMX_SC_PM_CLK_PER>;
269	clock-names = "ipg";
270	power-domains = <&pd IMX_SC_R_UART_0>;
271};
272