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 either
93			2: Contains the Resource and Clock ID value.
94			or
95			1: Contains the Clock ID value. (DEPRECATED)
96- clocks:		List of clock specifiers, must contain an entry for
97			each required entry in clock-names
98- clock-names:		Should include entries "xtal_32KHz", "xtal_24MHz"
99
100The clock consumer should specify the desired clock by having the clock
101ID in its "clocks" phandle cell.
102
103See the full list of clock IDs from:
104include/dt-bindings/clock/imx8qxp-clock.h
105
106Pinctrl bindings based on SCU Message Protocol
107------------------------------------------------------------
108
109This binding uses the i.MX common pinctrl binding[3].
110
111Required properties:
112- compatible:		Should be one of:
113			"fsl,imx8qm-iomuxc",
114			"fsl,imx8qxp-iomuxc",
115			"fsl,imx8dxl-iomuxc".
116
117Required properties for Pinctrl sub nodes:
118- fsl,pins:		Each entry consists of 3 integers which represents
119			the mux and config setting for one pin. The first 2
120			integers <pin_id mux_mode> are specified using a
121			PIN_FUNC_ID macro, which can be found in
122			<dt-bindings/pinctrl/pads-imx8qm.h>,
123			<dt-bindings/pinctrl/pads-imx8qxp.h>,
124			<dt-bindings/pinctrl/pads-imx8dxl.h>.
125			The last integer CONFIG is the pad setting value like
126			pull-up on this pin.
127
128			Please refer to i.MX8QXP Reference Manual for detailed
129			CONFIG settings.
130
131[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
132[2] Documentation/devicetree/bindings/power/power-domain.yaml
133[3] Documentation/devicetree/bindings/pinctrl/fsl,imx-pinctrl.txt
134
135RTC bindings based on SCU Message Protocol
136------------------------------------------------------------
137
138Required properties:
139- compatible: should be "fsl,imx8qxp-sc-rtc";
140
141OCOTP bindings based on SCU Message Protocol
142------------------------------------------------------------
143Required properties:
144- compatible:		Should be one of:
145			"fsl,imx8qm-scu-ocotp",
146			"fsl,imx8qxp-scu-ocotp".
147- #address-cells:	Must be 1. Contains byte index
148- #size-cells:		Must be 1. Contains byte length
149
150Optional Child nodes:
151
152- Data cells of ocotp:
153  Detailed bindings are described in bindings/nvmem/nvmem.txt
154
155Watchdog bindings based on SCU Message Protocol
156------------------------------------------------------------
157
158Required properties:
159- compatible: should be:
160              "fsl,imx8qxp-sc-wdt"
161              followed by "fsl,imx-sc-wdt";
162Optional properties:
163- timeout-sec: contains the watchdog timeout in seconds.
164
165SCU key bindings based on SCU Message Protocol
166------------------------------------------------------------
167
168Required properties:
169- compatible: should be:
170              "fsl,imx8qxp-sc-key"
171              followed by "fsl,imx-sc-key";
172- linux,keycodes: See Documentation/devicetree/bindings/input/input.yaml
173
174Thermal bindings based on SCU Message Protocol
175------------------------------------------------------------
176
177Required properties:
178- compatible:			Should be :
179				  "fsl,imx8qxp-sc-thermal"
180				followed by "fsl,imx-sc-thermal";
181
182- #thermal-sensor-cells:	See Documentation/devicetree/bindings/thermal/thermal-sensor.yaml
183				for a description.
184
185Example (imx8qxp):
186-------------
187aliases {
188	mu1 = &lsio_mu1;
189};
190
191lsio_mu1: mailbox@5d1c0000 {
192	...
193	#mbox-cells = <2>;
194};
195
196firmware {
197	scu {
198		compatible = "fsl,imx-scu";
199		mbox-names = "tx0", "tx1", "tx2", "tx3",
200			     "rx0", "rx1", "rx2", "rx3",
201			     "gip3";
202		mboxes = <&lsio_mu1 0 0
203			  &lsio_mu1 0 1
204			  &lsio_mu1 0 2
205			  &lsio_mu1 0 3
206			  &lsio_mu1 1 0
207			  &lsio_mu1 1 1
208			  &lsio_mu1 1 2
209			  &lsio_mu1 1 3
210			  &lsio_mu1 3 3>;
211
212		clk: clk {
213			compatible = "fsl,imx8qxp-clk", "fsl,scu-clk";
214			#clock-cells = <2>;
215		};
216
217		iomuxc {
218			compatible = "fsl,imx8qxp-iomuxc";
219
220			pinctrl_lpuart0: lpuart0grp {
221				fsl,pins = <
222					SC_P_UART0_RX_ADMA_UART0_RX	0x06000020
223					SC_P_UART0_TX_ADMA_UART0_TX	0x06000020
224				>;
225			};
226			...
227		};
228
229		ocotp: imx8qx-ocotp {
230			compatible = "fsl,imx8qxp-scu-ocotp";
231			#address-cells = <1>;
232			#size-cells = <1>;
233
234			fec_mac0: mac@2c4 {
235				reg = <0x2c4 8>;
236			};
237		};
238
239		pd: imx8qx-pd {
240			compatible = "fsl,imx8qxp-scu-pd", "fsl,scu-pd";
241			#power-domain-cells = <1>;
242		};
243
244		rtc: rtc {
245			compatible = "fsl,imx8qxp-sc-rtc";
246		};
247
248		scu_key: scu-key {
249			compatible = "fsl,imx8qxp-sc-key", "fsl,imx-sc-key";
250			linux,keycodes = <KEY_POWER>;
251		};
252
253		watchdog {
254			compatible = "fsl,imx8qxp-sc-wdt", "fsl,imx-sc-wdt";
255			timeout-sec = <60>;
256		};
257
258		tsens: thermal-sensor {
259			compatible = "fsl,imx8qxp-sc-thermal", "fsl,imx-sc-thermal";
260			#thermal-sensor-cells = <1>;
261		};
262	};
263};
264
265serial@5a060000 {
266	...
267	pinctrl-names = "default";
268	pinctrl-0 = <&pinctrl_lpuart0>;
269	clocks = <&uart0_clk IMX_SC_R_UART_0 IMX_SC_PM_CLK_PER>;
270	clock-names = "ipg";
271	power-domains = <&pd IMX_SC_R_UART_0>;
272};
273