From 40ca1b687155e07dac9650dc481ed98da6166b13 Mon Sep 17 00:00:00 2001 From: John Bonesio Date: Fri, 27 May 2011 18:45:50 -0400 Subject: ARM: zImage: Allow the appending of a device tree binary This patch provides the ability to boot using a device tree that is appended to the raw binary zImage (e.g. cat zImage .dtb > zImage_w_dtb). Signed-off-by: John Bonesio [nico: ported to latest zImage changes plus additional cleanups/improvements] Signed-off-by: Nicolas Pitre Acked-by: Grant Likely Acked-by: Tony Lindgren Tested-by: Shawn Guo Tested-by: Dave Martin Tested-by: Thomas Abraham Signed-off-by: Chinmay Kamat Change-Id: I93c54694a59b357eb550587b94c986dcb19ab954 Original: e2a6a3aafa9862c4a4b59f2a59b8f923d64a680e Reviewed-on: http://git-master/r/107422 Reviewed-by: Simone Willett Tested-by: Simone Willett --- arch/arm/Kconfig | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'arch/arm/Kconfig') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 0e57155f5050..fc9d147ae30e 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -1940,6 +1940,26 @@ config ZBOOT_ROM_SH_MOBILE_SDHI endchoice +config ARM_APPENDED_DTB + bool "Use appended device tree blob to zImage (EXPERIMENTAL)" + depends on OF && !ZBOOT_ROM && EXPERIMENTAL + help + With this option, the boot code will look for a device tree binary + (DTB) appended to zImage + (e.g. cat zImage .dtb > zImage_w_dtb). + + This is meant as a backward compatibility convenience for those + systems with a bootloader that can't be upgraded to accommodate + the documented boot protocol using a device tree. + + Beware that there is very little in terms of protection against + this option being confused by leftover garbage in memory that might + look like a DTB header after a reboot if no actual DTB is appended + to zImage. Do not leave this option active in a production kernel + if you don't intend to always append a DTB. Proper passing of the + location into r2 of a bootloader provided DTB is always preferable + to this option. + config CMDLINE string "Default kernel command string" default "" -- cgit v1.2.3