1The chosen node
2---------------
3The chosen node does not represent a real device, but serves as a place
4for passing data like which serial device to used to print the logs etc
5
6
7stdout-path property
8--------------------
9Device trees may specify the device to be used for boot console output
10with a stdout-path property under /chosen.
11
12Example
13-------
14/ {
15	chosen {
16		stdout-path = "/serial@f00:115200";
17	};
18
19	serial@f00 {
20		compatible = "vendor,some-uart";
21		reg = <0xf00 0x10>;
22	};
23};
24
25tick-timer property
26-------------------
27In a system there are multiple timers, specify which timer to be used
28as the tick-timer. Earlier it was hardcoded in the timer driver now
29since device tree has all the timer nodes. Specify which timer to be
30used as tick timer.
31
32Example
33-------
34/ {
35	chosen {
36		tick-timer = "/timer2@f00";
37	};
38
39	timer2@f00 {
40		compatible = "vendor,some-timer";
41		reg = <0xf00 0x10>;
42	};
43};
44
45u-boot,spl-boot-order property
46------------------------------
47
48In a system using an SPL stage and having multiple boot sources
49(e.g. SPI NOR flash, on-board eMMC and a removable SD-card), the boot
50device may be probed by reading the image and verifying an image
51signature.
52
53If the SPL is configured through the device-tree, the boot-order can
54be configured with the spl-boot-order property under the /chosen node.
55Each list element of the property should specify a device to be probed
56in the order they are listed: references (i.e. implicit paths), a full
57path or an alias is expected for each entry.
58
59A special specifier "same-as-spl" can be used at any position in the
60boot-order to direct U-Boot to insert the device the SPL was booted
61from there.  Whether this is indeed inserted or silently ignored (if
62it is not supported on any given SoC/board or if the boot-device is
63not available to continue booting from) is implementation-defined.
64Note that if "same-as-spl" expands to an actual node for a given
65board, the corresponding node may appear multiple times in the
66boot-order (as there currently exists no mechanism to suppress
67duplicates from the list).
68
69Example
70-------
71/ {
72	chosen {
73		u-boot,spl-boot-order = "same-as-spl", &sdmmc, "/sdhci@fe330000";
74	};
75};
76
77u-boot,spl-boot-device property
78-------------------------------
79
80This property is a companion-property to the u-boot,spl-boot-order and
81will be injected automatically by the SPL stage to notify a later stage
82of where said later stage was booted from.
83
84You should not define this property yourself in the device-tree, as it
85may be overwritten without warning.
86