aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/mediatek/patches-5.15/901-arm-add-cmdline-override.patch
blob: 6016128bd4a2000c419f4ed51bd1e014192ebfa4 (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
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1729,6 +1729,14 @@ config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEN
 
 endchoice
 
+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 CMDLINE
 	string "Default kernel command string"
 	default ""
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1162,6 +1162,17 @@ int __init early_init_dt_scan_chosen(uns
 	if (p != NULL && l > 0)
 		strlcat(data, p, min_t(int, strlen(data) + (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
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1942,6 +1942,14 @@ config CMDLINE_FORCE
 
 endchoice
 
+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 EFI_STUB
 	bool