rockchip: spl: support a 'same-as-spl'-specifier in the spl-boot-order

[people/ms/u-boot.git] / doc / device-tree-bindings / chosen.txt

diff --git a/doc/device-tree-bindings/chosen.txt b/doc/device-tree-bindings/chosen.txt
index 5625d210e8ce3844d545b7ca200408698b37b8ee..c96b8f7109053e21edca880f580c21bbdd325946 100644 (file)
--- a/doc/device-tree-bindings/chosen.txt
+++ b/doc/device-tree-bindings/chosen.txt
@@ -56,10 +56,20 @@ Each list element of the property should specify a device to be probed
 in the order they are listed: references (i.e. implicit paths), a full
 path or an alias is expected for each entry.
 
+A special specifier "same-as-spl" can be used at any position in the
+boot-order to direct U-Boot to insert the device the SPL was booted
+from there.  Whether this is indeed inserted or silently ignored (if
+it is not supported on any given SoC/board or if the boot-device is
+not available to continue booting from) is implementation-defined.
+Note that if "same-as-spl" expands to an actual node for a given
+board, the corresponding node may appear multiple times in the
+boot-order (as there currently exists no mechanism to suppress
+duplicates from the list).
+
 Example
 -------
 / {
        chosen {
-               u-boot,spl-boot-order = &sdmmc, "/sdhci@fe330000";
+               u-boot,spl-boot-order = "same-as-spl", &sdmmc, "/sdhci@fe330000";
        };
 };