Re: [Qemu-ppc] qemu-system-ppc64 -M ppce500 always booting to qemu monitor console plus no output on serial console

[Do Vincenzo]

On 18.12.15 09:12, Do Vincenzo wrote:
> On 17.12.15 16:39, Alexander Graf wrote:
>> On 17.12.15 14:14, Do Vincenzo wrote:
>>> On Thu, 17 Dec 2015, BALATON Zoltan wrote:
>>>> On Thu, 17 Dec 2015, Do Vincenzo wrote:
>>>>> Ok, so the last IN occurrence is this one: 0x000000000001fad8:  b       
>>>>> 0x1fad8
>>>>> here's the full log of the last two IN: http://paste.ubuntu.com/14072313/
>>>>> after that, the log keeps going on but without any IN.
>>>>
>>>> It is jumping to itself so it reached a halt condition.
>>>>
>>>>> Also I've tried to print what's at the 0x1fad8 address but the output is 
>>>>> empty.
>>>>> I've printed the log buffer with the -cpu parameter: 
>>>>> http://paste.ubuntu.com/14072246/
>>>>
>>>> I see a kernel panic in this referring to the device tree:
>>>>
>>>> BUG: Failed verifying flat device tree, bad version?
>>>> What that means though I have no idea but you could try searching for
>>>> this.
>>>>
>>>> Regards,
>>>> BALATON Zoltan
>>>
>>> Thank you for your reply.
>>>
>>> The error seems to come from the "/arch/powerpc/kernel/prom.c" file at line 
>>> 650.
>>>
>>> From this patch: 
>>> https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-August/120444.html
>>> I can guess that the version of the dtb used for the guest is too old. So 
>>> which dtb should I use?
>>> I tried using the mpc8544ds.dtb compiled from a 4.x mainline linux but I 
>>> get the same error.
>>>
>>> And also, shouldn't I be able to see this error on the console? Why it 
>>> doesn't get printed there?
>>
>> That one's easy - the fdt is used to tell Linux where to print
>> something. So without working device tree parsing, you don't see output,
>> because Linux doesn't know where the serial console lives.
>
> Of course! I should have figured it out by myself....
>
>> As to why it doesn't like the fdt we generate inside QEMU, I don't know.
>> Do you manage to get into U-Boot when you run QEMU without -kernel?
>> Also, please give 2.5.0 a shot - compile it with its built-in device
>> tree code (git submodule update --init dtc).
>
> Yes I manage to get into U-Boot.
>
>> To at least sanity check that *something* works at all :), please try
>> and grab a known-working uImage from
>> http://csgraf.de/tmp/e5500-bug/uImage. Then run it using
>>
>> qemu-system-ppc64 -M ppce500 -nographic -cpu e5500 -kernel uImage
>>
>> Alex
>
> I tested your uImage and it works both on my laptop and on the Freescale 
> board!
> So I guess I'm doing something wrong when generating mine. Could you please
> share how did you generate yours?
>
> Regards,
> Vincenzo Do

By looking at the configuration of the uImage you provided I was able to 
generate
my own uImage with a 4.4.0-rc3 kernel which boots without problems. 

Thank you for your help!

Regards,
Vincenzo Do