Re: 2.6.16-rc1-mm2 pata driver confusion

From: "Randy.Dunlap" <rdunlap@xenotime.net>
To: Ed Sweetman <safemode@comcast.net>
Cc: "Randy.Dunlap" <rdunlap@xenotime.net>,
	Alan Cox <alan@lxorguk.ukuu.org.uk>,
	linux-kernel@vger.kernel.org, akpm@osdl.org
Subject: Re: 2.6.16-rc1-mm2 pata driver confusion
Date: Tue, 24 Jan 2006 15:07:21 -0800 (PST)	[thread overview]
Message-ID: <Pine.LNX.4.58.0601241503110.26036@shark.he.net> (raw)
In-Reply-To: <43D6B1B2.4080400@comcast.net>

On Tue, 24 Jan 2006, Ed Sweetman wrote:

> Randy.Dunlap wrote:
>
> >On Tue, 24 Jan 2006, Ed Sweetman wrote:
> >
> >>Alan Cox wrote:
> >>
> >>>On Maw, 2006-01-24 at 01:43 -0500, Ed Sweetman wrote:
> >>>
> >>>
> >>>>problem.  The problem is that there appears to be two nvidia/amd ata
> >>>>drivers and I'm unsure which I should try using, if i compile both in,
> >>>>which get loaded first (i assume scsi is second to ide) and if i want my
> >>>>pata disks loaded under the new libata drivers, will my cdrom work under
> >>>>them too, or do i still need some sort of regular ide drivers loaded
> >>>>just for cdrom (to use native ata mode for recording access).
> >>>>
> >>>>
> >>>The goal of the drivers/scsi/pata_* drivers is to replace drivers/ide in
> >>>its entirity with code using the newer and cleaner libata logic. There
> >>>is still much to do but my SIL680, SiS, Intel MPIIX, AMD and VIA boxes
> >>>are using libata and the additional patch patches still queued
> >>>
> >>>
> >>>>1.  Atapi is most definitely not supported by libata, right now.
> >>>>
> >>>>
> >>>It works in the -mm tree.
> >>>
> >>>
> >>Intriguing, when I had no ide chipset compiled in kernel, only libata
> >>drivers, I got no mention at all about my dvd writer.  I even had the
> >>scsi cd driver installed and generic devices, still nothing seemed to
> >>initialize the dvd drive.  It detected the second pata bus but no
> >>devices attached to it.
> >>
> >>this is using the kernel mentioned in the subject header.
> >>2.6.16-rc1-mm2.  using the amd/nvidia drivers for pata and sata.
> >>
> >>Is there anything i can do to give more info to the list to figure out
> >>why my atapi writer is being ignored by pata even when there are no ide
> >>drivers loaded?
> >>
> >
> >Currently you need to use libata.atapi_enabled=1
> >(assuming that libata is in the kernel image, not a loadable module).
> >
> >I just built/tested this also, working for me as well.
> >(hard drives, not ATAPI)
> >
> >
> I assume libata.atapi_enabled=1 is a boot arg, not some structure member
> in the source for the pata driver that i need to set to 1, correct?

Yes, it's a kernel boot option if libata is in the kernel image.
If libata is a loadable module, just use something like
	modprobe libata atapi_enabled=1

> And you just built and tested it, how did you test if the atapi argument
> worked when you then say "not ATAPI" as something you tested?

Sorry, I mean that I built and booted a kernel with libata/PATA
hard drive (vs. legacy drivers/ide/ PATA support).  I have not
tested ATAPI at all and didn't mean to imply that I had.

I reported on libata.atapi_enabled=1 based on documentation
and other emails that I have read.

> In any case, i'll try out libata.atapi_enabled=1 and see if it detects
> the dvd drive.

HTH.  Please continue to post any questions or problems.
-- 
~Randy