aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/mpc85xx/patches-4.19/102-powerpc-add-cmdline-override.patch
blob: a99555f949bb4c9f5565c704cbb04c932d677dd8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -809,6 +809,14 @@ config CMDLINE_FORCE
 	  This is useful if you cannot or don't want to change the
 	  command-line options your boot loader passes to the kernel.
 
+config CMDLINE_OVERRIDE
+    bool "Use alternative cmdline from device tree"
+    help
+      Some bootloaders may have uneditable bootargs. While CMDLINE_FORCE can
+      be used, this is not a good option for kernels that are shared across
+      devices. This setting enables using "chosen/cmdline-override" as the
+      cmdline if it exists in the device tree.
+
 config EXTRA_TARGETS
 	string "Additional default image types"
 	help
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1091,6 +1091,17 @@ int __init early_init_dt_scan_chosen(uns
 	if (p != NULL && l > 0)
 		strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
 
+    /* CONFIG_CMDLINE_OVERRIDE is used to fallback to a different
+     * device tree option of chosen/bootargs-override. This is
+     * helpful on boards where u-boot sets bootargs, and is unable
+     * to be modified.
+     */
+#ifdef CONFIG_CMDLINE_OVERRIDE
+	p = of_get_flat_dt_prop(node, "bootargs-override", &l);
+	if (p != NULL && l > 0)
+		strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
+#endif
+
 	/*
 	 * CONFIG_CMDLINE is meant to be a default in case nothing else
 	 * managed to set the command line, unless CONFIG_CMDLINE_FORCE