Commit 1b7898ee276b "powerpc/boot: Use the pre-boot decompression API" breaks boot

[Heiner Kallweit]

Am 12.10.2016 um 06:26 schrieb Oliver O'Halloran:
> On Tue, Oct 11, 2016 at 7:06 AM, Heiner Kallweit <hkallweit1 at gmail.com> wrote:
>>> IMHO in case of using cuboot no CONFIG_KERNEL_<COMPR TYPE> config option
>>> should be set and Makefile + code in arch/powerpc/boot should be able
>>> to deal with this situation:
>>> - don't copy and build the decompression stuff
>>> - use an alternative version of prep_kernel() in main.c which doesn't
>>>   attempt to decompress the kernel image
>>>
>>> This should be a cleaner solution than probing the kernel image whether
>>> it's compressed or not.
>>>
>>
>> This would be the patch implementing the idea. Advantage is that all
>> the unnecessary decompression code isn't built. Works fine for me.
> 
> I don't think this approach is viable. The wrapper code is shared
> among the various output image formats some of which *will* contain a
> compressed kernel image so we can't simply remove the decompressor
> from the wrapper. A random example I found in the makefile was
> CONFIG_BAMBOO:
> 
>> image-$(CONFIG_BAMBOO) += treeImage.bamboo cuImage.bamboo
> 
> When building for this platform Kbuild will produce treeboot and a
> cuboot image. Unlike uboot, Treeboot doesn't do any decompression so
> the wrapper needs to decompress the kernel itself. The probing
> solution more or less matches the old behaviour (which we know works)
> so I think we should just stick with that.
> 
> - Oliver
> 
Indeed, I also figured that out later. As you say, then let's stick
with re-introducing the probing. I'll send the patch for this.

Heiner