Re: linux-next - multi-omap image fails to boot on omap3/4

Anand Gadiyar
2010-10-22T20:16:09Z

On 10/22/2010 2:52 PM, Tony Lindgren wrote:
> * Anand Gadiyar<gadiyar@ti.com> [101022 06:59]:
>> Tony Lindgren wrote:
>>> * Gadiyar, Anand<gadiyar@ti.com> [101019 23:21]:
>>
>> ...
>>
>>>>>>>>>> linux-next, as of 20101019, built with the
>> omap2plus_defconfig fails
>>>>>>>>>> to boot on omap3 and omap4. (I've disabled CONFIG_ARCH_OMAP2
>> or
>>>>>>>>>> CONFIG_SWP_EMULATE to get the image to build). Building with
>> only
>>>>>>>>>> ARCH_OMAP3 allows the resultant image to boot up on OMAP3.
>> Likewise,
>>>>>>>>>> an image built with only ARCH_OMAP4 boots up on OMAP4 boards.
>>>>>>>>>>
>>>>>>>>>> earlyprintk does not provide any additional prints after
>>>>>>>>>> "Uncompressing Linux... done, booting the kernel."
>>>>>>>>>>
>>>>>>>>>> Any ideas where to look?
>>>>>>>>>
>>
>> ...
>>
>>>>
>>>> I tried disabling CONFIG_SMP and CONFIG_SMP_ON_UP, and the resulting
>>>> image booted up just fine.
>>>
>>> Looks like it's caused by this patch:
>>>
>>> "ARM: hotplug cpu: Keep processor information, startup code&
>>> __lookup_processor_type"
>>>
>>> It's probably trashing registers it shouldn't. Will take a look and post
>>> something to linux-arm-kernel.
>>>
>>
>> I'm not sure what's going on, but looks like linux-next as of
>> 20101022 boots up fine on panda. I can't explain it, as I couldn't
>> find anything related to the patch you mentioned.
>
> Yeah, it's an alignment issue that's why it sometimes works depending
> on the Kconfig options selected..
>
> For rererence, posted a fix for that at:
>
> https://patchwork.kernel.org/patch/276161/
>
> Tony

The patch seems to work - thanks! Just curious, how do you go about
debugging an issue like this?

- Anand