[regression] 2.6.39-rc[1-3] fail to boot on G5 PowerMac

[Hugh Dickins]

On Thu, Apr 14, 2011 at 2:54 PM, Benjamin Herrenschmidt
<benh at kernel.crashing.org> wrote:
> On Thu, 2011-04-14 at 14:25 -0700, Hugh Dickins wrote:
>>
>> Something worth trying: turn off CONFIG_IDE.  That's what I need to
>> boot 2.6.39-rc[1-3] on PowerPC G5.
>>
>> I know Jens has been fixing problems with IDE versus his plug/unplug
>> changes, but it's still not fixed for me in rc3.
>>
>> In other mail http://lkml.org/lkml/2011/4/14/614
>> I see Linus recommending his post-rc3 commit 6631e635c65d
>> but I've not tried that myself yet.
>
> Well, the disk is SATA so it's CONFIG_ATA/libata, which works fine here,
> unless you somewhat replaced your CD-ROM with a legacy IDE disk :-) Or
> maybe the problem is related to the CD-ROM drive. There's a libata
> driver for it nowadays, so you can use PATA_MACIO instead of IDE_PMAC

Thanks for that, Ben: I remember you were brewing up such a driver,
but I missed when it actually went in.  I can confirm that switching
off CONFIG_IDE and switching on CONFIG_PATA_MACIO and
CONFIG_BLK_DEV_SR now gives me a booting system with a working CD-ROM
(though I've not yet tried burning).

Whereas CONFIG_IDE=y with current git still does not boot: hangs for a
minute or three around the windfarm announcements, then an endless
splurge of hda error messages - sorry, I'm not being helpful, other
worries...

Hugh