ide-pmac lost interrupt w/2.6.8.1 (DMA problem?)

[Albrecht Dreß]

--=-ZL3Kjvdbms5b1y7HAQnx
Content-Type: text/plain; charset=ISO-8859-15; DelSp=Yes; Format=Flowed
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

Hi,

when trying to get Linux 2.6.8.1 running on my PMac G4/800 "Silver" I ran =20
into something which might be a DMA problem.

First, the box works flawlessly with 2.4.25-ben1. When booting 2.6.8.1, =20
the boot screen hangs when probing the first hard disk, with (inter alia) =20
the following messages for hda (written down by hand, as the boot process =20
doesn't succeed):

ide0 Apple Keylargo ATA 4
hda IBM-IC35L040AVVA07-0   # the drive the box came with
set UDMA timing for mode 4, reg 0x0c50038c
Enabling Ultra DMA 4

and then several

hda: lost interrupt
hda:<3> ide-pmac lost interrupt, dma status 8080

I guess the drive has problems with udma 4, but I have no idea how I can =20
set it to a safer value... I tried to disable ide dma in the kernel =20
completely (yes, I know that it would make the box really slow), but then =20
Linux doesn't compile any more. Of course, the smarter way would be if =20
Linux would detect itself that that's too fast and fall back =20
appropriately.

Any help is really welcome!

Cheers, Albrecht.

--=20
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Albrecht Dre=DF  -  Johanna-Kirchner-Stra=DFe 13  -  D-53123 Bonn (Germany=
)
       Phone (+49) 228 6199571  -  mailto:albrecht.dress@arcor.de
_________________________________________________________________________


--=-ZL3Kjvdbms5b1y7HAQnx
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (GNU/Linux)

iD8DBQBBTzZxn/9unNAn/9ERAs4lAJ9gdyjeyta67PSP+ie6/ncEQAG9jgCfRhx1
IUWuZ+Jvug0rmgdBzT1Mwgo=
=x86X
-----END PGP SIGNATURE-----

--=-ZL3Kjvdbms5b1y7HAQnx--