Re: SATA port multiplier(Marvell 6121 with ahci) and Marvell 4140, simg 3726

[Tejun Heo <tj@kernel.org>]

Tejun Heo wrote:
> KueiHuan Chen wrote:
>> Hello,
>>
>>   We got some problem while evaluation port multipiler with libata, we
>> had tested with two sata chip, one is sil-3132, the another is Marvell
>> 6121. And we also have two port multiplie: Marvell 4140 and Sil-3726.
>> Our kernel version is kernel-2.6.24 with Marvell 5281 platform.
>>
>>   Testing result:
>>
>>   Sil 3132 with 3726 and 4140: everything looks like fine.
>>
>>   Marvell 6121 with 3726 and 4140(using ahci.c): both port multipiler
>> would got problem. It can't be detected whether hotplug or at boot time.
>> But the disk detection is fine without port multiplier.
>>
>>   Because we can't upgrade kernel to latest version so quickly, is there
>> any hint or solution for us ?
> 
> mv PMP support was added very recently.  2.6.26 has it.

Heh.. didn't read the last line.  If you can't upgrade the kernel,
you'll need to backport.  We had to fix core PMP support quite a bit to
get mv working, so you'll need to backport whole libata, which usually
isn't too difficult.  Someone knowledgeable would be able to pull it in
a few days but if you don't know what you're doing it can be pretty
hairy.  :-)

-- 
tejun