multi-core ARM configuration

[Hannes Mehnert]

(sorry, I didn't cc the mailing list in my reply, thus resending the mail)

On 10/23/2014 14:08, Niels Möller wrote:
> Hannes Mehnert <hannes at mehnert.org> writes:
> 
>> This is a cubieboard2
>> (http://docs.cubieboard.org/products/start#cubieboard2).
>>
>> mirage at cubieboard2:~$ cat /proc/cpuinfo
>> processor       : 0
>> model name      : ARMv7 Processor rev 4 (v7l)
>> Features        : swp half thumb fastmult vfp edsp thumbee neon vfpv3
>> tls vfpv4 idiva idivt vfpd32 lpae evtstrm
>> CPU implementer : 0x41
>> CPU architecture: 7
>> CPU variant     : 0x0
>> CPU part        : 0xc07
>> CPU revision    : 4
>>
>> processor       : 1
>> model name      : ARMv7 Processor rev 4 (v7l)
>> Features        : swp half thumb fastmult vfp edsp thumbee neon vfpv3
>> tls vfpv4 idiva idivt vfpd32 lpae evtstrm
>> CPU implementer : 0x41
>> CPU architecture: 7
>> CPU variant     : 0x0
>> CPU part        : 0xc07
>> CPU revision    : 4
>>
>> Hardware        : Allwinner sun7i (A20) Family
>> Revision        : 0000
>> Serial          : 0000000000000000
> 
> I see. I wonder why I get different output from my board, if it's just
> that you use a more recent kernel or something.
> 
> Using the first CPU part line seems reasonable, as you do in your patch.
> Hopefully, they'll be identical. But I guess in principle, it's possible
> to have a system with two cpu sockets populated with slightly different
> cpus? Torbjörn, do we care about that case for other archs?


When adjusting config.guess I read through it, and there is at least
for rs6* / powerpc* a very similar code part (line 449):
    x=`grep "^cpu[ 	]" /proc/cpuinfo | head -n 1`

I'm not sure what a SoC with SMP and heterogeneous CPUs outputs in
/proc/cpuinfo.


Cheers,

Hannes