[Buildroot] [RFC/PATCH] linux: remove the zImage before rebuild

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Hello,

On Fri, 17 Jul 2015 11:49:04 -0700, Hollis Blanchard wrote:

> A bit of a tangent now, but I am trying to write a recipe for another 
> bootwrapper, which prepends a little code to a zImage/DTB combo. Right 
> now, it basically boils down to this:
> 
>     define BOOT_WRAPPER_ARM_BUILD_CMDS
> 
>          $(MAKE) CROSS_COMPILE=$(TARGET_CROSS) DTBIMAGE=$(BINARIES_DIR)/zImage -C $(@D)
> 
>     endef
> 
> 
> Practically speaking, I think the bootwrapper is only really useful in 
> the BR2_LINUX_KERNEL_APPENDED_ZIMAGE case, and I can enforce that via 
> Kconfig dependencies, so I can assume the kernel name is "zImage".
> 
> If your idea above is implemented, would I need to duplicate the 
> linux.mk logic around  BR2_LINUX_KERNEL_USE_INTREE_DTS, 
> BR2_LINUX_KERNEL_INTREE_DTS_NAME, BR2_LINUX_KERNEL_USE_CUSTOM_DTS, and 
> BR2_LINUX_KERNEL_CUSTOM_DTS_PATH? Or is there a better way to do this?

We already have a similar case in the boot-wrapper-aarch64 package. I
am indeed not sure how that would work with appended DTB and multiple
zImage generated. Needs some thought, indeed.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com