Re: WD_QUIRK_FORCE_LBA48

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Mon, Dec 14, 2009 at 08:37:26PM +0000, David Laight wrote:
> On Mon, Dec 14, 2009 at 04:27:51PM +0100, Manuel Bouyer wrote:
> > >         if (wd->sc_flags & WDF_LBA48 &&
> > > -           (wd->sc_wdc_bio.blkno > LBA48_THRESHOLD ||
> > > +           (wd->sc_wdc_bio.blkno +
> > > +               wd->sc_wdc_bio.bcount / wd->sc_dk.dk_label->d_secsize >
> > > +               LBA48_THRESHOLD ||
> > 
> > but please make this (LBA48_THRESHOLD + 1). Otherwise the last
> > LBA24 sector will be inaccessible on non-LBA48 controllers.
> 
> Actually I think someone pointed out that the max sector number
> for LBA28 is sector 0xffffffe - the maximum value for the 'number of
> sectors addressable with LBA28' is 0xfffffff.

that's true in ATA7. but previous standards didn't impose restrictions
on the content of words 60-61 of IDENTIFY, nor did they state that
LBA28's last sector is 0xfffffe.
I also didn't see in ATA7 restrictions on LBA28's addressing, only on
the content if words 60-61 of IDENTIFY.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
--