KumiSystems/openwrtv4
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

mpc85xx: Add cmdline override patch

Browse source 
This patch adds a new kernel option called CONFIG_CMDLINE_OVERRIDE. This
setting is for devices with locked down u-boot environments, where users
are unable to change the default bootargs. When set, the fdt driver will
propagate the cmdline for the kernel from chosen/bootargs-override
instead of chosen/bootargs as long as it exists within the DTB.

Signed-off-by: Chris Blake <chrisrblake93@gmail.com>
This commit is contained in:
Chris Blake 2017-09-30 11:14:20 -05:00 committed by Hauke Mehrtens
parent a92f73e922
commit 8cd6686ef8
2 changed files with 38 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
target/linux/mpc85xx/config-4.9
View file

@ -37,6 +37,7 @@ CONFIG_CLONE_BACKWARDS=y
CONFIG_CLZ_TAB=y
CONFIG_CMDLINE="console=ttyS0,115200"
CONFIG_CMDLINE_BOOL=y
CONFIG_CMDLINE_OVERRIDE=y
# CONFIG_CORENET_GENERIC is not set
# CONFIG_CPM2 is not set
CONFIG_CPU_BIG_ENDIAN=y

37
target/linux/mpc85xx/patches-4.9/102-powerpc-add-cmdline-override.patch Normal file
View file

@ -0,0 +1,37 @@
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -707,6 +707,14 @@ 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
@@ -1079,6 +1079,17 @@ 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