Re: libsata doesn't like bus without master

[Robert Hancock <hancockr@shaw.ca>]

Patrick Ale wrote:
> On 2/11/07, Robert Hancock <hancockr@shaw.ca> wrote:
> > Patrick Ale wrote:
> > > Something unrelated to the tests I am doing.
> > >
> > > I found out that the libsata driver doesn't really cope or likes the
> > > idea that you might have a controller without a master drive
> > > configured.
> > >
> > > In this case on ATA2 I have a CDROM drive, connected as slave.
> > > ATA: abnormal status 0x7F on port 0x177
> > > ATA: abnormal status 0x7F on port 0x177
> > > ata2.01: ATAPI, max UDMA/66
> > > ata2.01: configured for UDMA/66
> >
> > Having a single drive on the channel configured as slave is not really a
> > legal configuration. (I believe the ATA standards say that it's
> > something that a host controller/driver/OS is allowed to support, but it
> > is not required to.) A single drive should always be set to master (and
> > connected to the end of the cable and not the middle, by the way).
>
> It is very legal when one of your harddisks blows out and you take it
> out temporarely and have no money for a replacement IMO. But then
> again, this is probably an abnormality.

Then in that case you should set the remaining drive as master. That's 
just the way PATA is. A lot of BIOSes won't even detect a drive that's 
set as slave with no master present.

> But still, it even complains when no drive is attached to a controller
> at all. Since when you buy an add-on PCI card you get 2 connectors
> even when you want to add one harddisk how does one deal with that?

Yeah, that's a better point. It's not really complaining, but we could 
probably have a better way of suppressing that message. I think it's 
largely there so that we can debug issues with drives not being detected 
when they should.

--
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/

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