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,imx8qm-clock"
90			  "fsl,imx8qxp-clock"
91			followed by "fsl,scu-clk"
92- #clock-cells:		Should be 1. Contains the Clock ID value.
93- clocks:		List of clock specifiers, must contain an entry for
94			each required entry in clock-names
95- clock-names:		Should include entries "xtal_32KHz", "xtal_24MHz"
96
97The clock consumer should specify the desired clock by having the clock
98ID in its "clocks" phandle cell.
99
100See the full list of clock IDs from:
101include/dt-bindings/clock/imx8qxp-clock.h
102
103Pinctrl bindings based on SCU Message Protocol
104------------------------------------------------------------
105
106This binding uses the i.MX common pinctrl binding[3].
107
108Required properties:
109- compatible:		Should be one of:
110			"fsl,imx8qm-iomuxc",
111			"fsl,imx8qxp-iomuxc",
112			"fsl,imx8dxl-iomuxc".
113
114Required properties for Pinctrl sub nodes:
115- fsl,pins:		Each entry consists of 3 integers which represents
116			the mux and config setting for one pin. The first 2
117			integers <pin_id mux_mode> are specified using a
118			PIN_FUNC_ID macro, which can be found in
119			<dt-bindings/pinctrl/pads-imx8qm.h>,
120			<dt-bindings/pinctrl/pads-imx8qxp.h>,
121			<dt-bindings/pinctrl/pads-imx8dxl.h>.
122			The last integer CONFIG is the pad setting value like
123			pull-up on this pin.
124
125			Please refer to i.MX8QXP Reference Manual for detailed
126			CONFIG settings.
127
128[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
129[2] Documentation/devicetree/bindings/power/power-domain.yaml
130[3] Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt
131
132RTC bindings based on SCU Message Protocol
133------------------------------------------------------------
134
135Required properties:
136- compatible: should be "fsl,imx8qxp-sc-rtc";
137
138OCOTP bindings based on SCU Message Protocol
139------------------------------------------------------------
140Required properties:
141- compatible:		Should be one of:
142			"fsl,imx8qm-scu-ocotp",
143			"fsl,imx8qxp-scu-ocotp".
144- #address-cells:	Must be 1. Contains byte index
145- #size-cells:		Must be 1. Contains byte length
146
147Optional Child nodes:
148
149- Data cells of ocotp:
150  Detailed bindings are described in bindings/nvmem/nvmem.txt
151
152Watchdog bindings based on SCU Message Protocol
153------------------------------------------------------------
154
155Required properties:
156- compatible: should be:
157              "fsl,imx8qxp-sc-wdt"
158              followed by "fsl,imx-sc-wdt";
159Optional properties:
160- timeout-sec: contains the watchdog timeout in seconds.
161
162SCU key bindings based on SCU Message Protocol
163------------------------------------------------------------
164
165Required properties:
166- compatible: should be:
167              "fsl,imx8qxp-sc-key"
168              followed by "fsl,imx-sc-key";
169- linux,keycodes: See Documentation/devicetree/bindings/input/input.yaml
170
171Thermal bindings based on SCU Message Protocol
172------------------------------------------------------------
173
174Required properties:
175- compatible:			Should be :
176				  "fsl,imx8qxp-sc-thermal"
177				followed by "fsl,imx-sc-thermal";
178
179- #thermal-sensor-cells:	See Documentation/devicetree/bindings/thermal/thermal-sensor.yaml
180				for a description.
181
182Example (imx8qxp):
183-------------
184aliases {
185	mu1 = &lsio_mu1;
186};
187
188lsio_mu1: mailbox@5d1c0000 {
189	...
190	#mbox-cells = <2>;
191};
192
193firmware {
194	scu {
195		compatible = "fsl,imx-scu";
196		mbox-names = "tx0", "tx1", "tx2", "tx3",
197			     "rx0", "rx1", "rx2", "rx3",
198			     "gip3";
199		mboxes = <&lsio_mu1 0 0
200			  &lsio_mu1 0 1
201			  &lsio_mu1 0 2
202			  &lsio_mu1 0 3
203			  &lsio_mu1 1 0
204			  &lsio_mu1 1 1
205			  &lsio_mu1 1 2
206			  &lsio_mu1 1 3
207			  &lsio_mu1 3 3>;
208
209		clk: clk {
210			compatible = "fsl,imx8qxp-clk", "fsl,scu-clk";
211			#clock-cells = <1>;
212		};
213
214		iomuxc {
215			compatible = "fsl,imx8qxp-iomuxc";
216
217			pinctrl_lpuart0: lpuart0grp {
218				fsl,pins = <
219					SC_P_UART0_RX_ADMA_UART0_RX	0x06000020
220					SC_P_UART0_TX_ADMA_UART0_TX	0x06000020
221				>;
222			};
223			...
224		};
225
226		ocotp: imx8qx-ocotp {
227			compatible = "fsl,imx8qxp-scu-ocotp";
228			#address-cells = <1>;
229			#size-cells = <1>;
230
231			fec_mac0: mac@2c4 {
232				reg = <0x2c4 8>;
233			};
234		};
235
236		pd: imx8qx-pd {
237			compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd";
238			#power-domain-cells = <1>;
239		};
240
241		rtc: rtc {
242			compatible = "fsl,imx8qxp-sc-rtc";
243		};
244
245		scu_key: scu-key {
246			compatible = "fsl,imx8qxp-sc-key", "fsl,imx-sc-key";
247			linux,keycodes = <KEY_POWER>;
248		};
249
250		watchdog {
251			compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
252			timeout-sec = <60>;
253		};
254
255		tsens: thermal-sensor {
256			compatible = "fsl,imx8qxp-sc-thermal", "fsl,imx-sc-thermal";
257			#thermal-sensor-cells = <1>;
258		};
259	};
260};
261
262serial@5a060000 {
263	...
264	pinctrl-names = "default";
265	pinctrl-0 = <&pinctrl_lpuart0>;
266	clocks = <&clk IMX8QXP_UART0_CLK>,
267		 <&clk IMX8QXP_UART0_IPG_CLK>;
268	clock-names = "per", "ipg";
269	power-domains = <&pd IMX_SC_R_UART_0>;
270};
271