Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 28 Aug 2003 10:40:15 -0400
From:      Anish Mistry <mistry.7@osu.edu>
To:        Soren Schmidt <sos@spider.deepcore.dk>
Cc:        freebsd-current@freebsd.org
Subject:   Re: ATAng no PIO fallback?
Message-ID:  <200308281040.15343.mistry.7@osu.edu>
In-Reply-To: <200308280624.h7S6O8nr020810@spider.deepcore.dk>
References:  <200308280624.h7S6O8nr020810@spider.deepcore.dk>

next in thread | previous in thread | raw e-mail | index | archive | help

--Boundary-02=_PRhT/uGo70PtGpv
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Content-Description: signed data
Content-Disposition: inline

On Thursday 28 August 2003 02:24 am, you wrote:
> It seems Anish Mistry wrote:
> -- Start of PGP signed section.
> > On Tuesday 26 August 2003 10:27 pm, Anish Mistry wrote:
> > > After removing atapicam from my kernel, so no panics on boot I decide=
d=20
to=20
> > see
> > > it DMA was fixed for my CD/DVD combo drive.  I changed the
> > > hw.ata.atapi_dma=3D"0"
> > > to hw.ata.atapi_dma=3D"1" in my /boot/loader.conf.  After a reboot I =
tried=20
to
> > > access my cdrom drive, and got the following error messages, which is=
=20
very
> > > similar to the messages when trying to dma before ATAng:
> > > Aug 26 22:09:34 littleguy kernel: acd0: WARNING - READ_CD recovered f=
rom
> > > missing interrupt
> > > Aug 26 22:09:34 littleguy kernel: acd0: WARNING - READ_CD UDMA ICRC=20
error
> > > (retrying request)
> > >=20
> > > The problem is that before with DMA enabled it would try dma a few ti=
mes=20
> > fail,
> > > and then fall back to PIO, whcih though annoying still left the drive=
 in=20
a
> > > useable condition.  Where as now the drive just stays stuck and=20
unusable.
> > >=20
> > > .....
> > Anyone thinking about looking into this?  I'll just submit a PR, in a d=
ay=20
or 2=20
> > if there is no resposne.
> > Thanks,
>=20
> There is no PIO fallback in ATAng (so far), if you know that your ATAPI=20
device=20
> doesn't do DMA why on earth do you enable it ?
>=20
Because the drive does support DMA.  I've tested to see it DMA actually wor=
ks=20
in windows, PIO vs DMA while playing a DVD, and there is a big difference,=
=20
and I can only assume that it works.
> -S=F8ren
>=20
>=20

=2D-=20
Anish Mistry

--Boundary-02=_PRhT/uGo70PtGpv
Content-Type: application/pgp-signature
Content-Description: signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.2 (FreeBSD)

iD8DBQA/ThRPxqA5ziudZT0RAkcUAJ9ZvxK0YJIuzodO/CpvdG8QtpkQAgCbBMMz
/5tXA+tiUCLrxGHZ8m9z3kI=
=ajF3
-----END PGP SIGNATURE-----

--Boundary-02=_PRhT/uGo70PtGpv--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200308281040.15343.mistry.7>