certain ATA-6 drives including CF cards.
The IDE geometry of the PC98 is calculated from the drive capacity.
In addition to the algorithm in NEC BIOS, a variety of algorithms are
provided by 3'rd party boards and BIOS hacks. This change has
implemented the three algorithms: IDE BIOS compatible mode, SCSI BIOS
compatible mode and same way as the previous version. The tunable
machdep.ad_geom_method selects the algorithm.
I have been using this change for a year with CF cards.
Reminded by: nyan
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