[PATCH] powerpc: Support CMDLINE_EXTEND

[Chris Packham <chris.packham@alliedtelesis.co.nz>]

Device tree aware platforms can make use of CMDLINE_EXTEND to extend the
kernel command line provided by the bootloader. This is particularly
useful to set parameters for built-in modules that would otherwise be
done at module insertion. Add support for this in the powerpc
architecture.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
---
 arch/powerpc/Kconfig | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index d8dcd8820369..cd9b3974aa36 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -851,6 +851,11 @@ config CMDLINE
 	  some command-line options at build time by entering them here.  In
 	  most cases you will need to specify the root device here.
 
+choice
+	prompt "Kernel command line type" if CMDLINE != ""
+	default CMDLINE_FORCE
+	depends on CMDLINE_BOOL
+
 config CMDLINE_FORCE
 	bool "Always use the default kernel command string"
 	depends on CMDLINE_BOOL
@@ -860,6 +865,13 @@ 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_EXTEND
+	bool "Extend bootloader kernel arguments"
+	help
+	  The command-line arguments provided by the boot loader will be
+	  appended to the default kernel command string.
+endchoice
+
 config EXTRA_TARGETS
 	string "Additional default image types"
 	help
-- 
2.22.0