[vox-tech] dma and pcmcia-ide

[David Margolis]

hello all.

i just got a exp pcmcia (cardbus?) dvd drive off eBay for a pretty good
deal.  before i bought it, i did some research on the pcmcia-ide driver
and found a wealth of info on pcmcia cdrom/cdrw drives on linux, but next
to no info on dvd drives (save entries on mobilix.org that said stuff to
the effect of _this should work_ or _probably works_).   anyway, i took a
chance, i got the thing, got it installed (after some /etc/pcmcia/ide.conf
trickery) and am able to actually view and play dvds with it.

the problem is that it's real slow.  i'm using mplayer (which i use with
no problems on my desktop system).
to make sure the thing did work i installed win98 on the same machine just
to see.  sure enough, with my system (celeron 500/160mb ram/4mb ati
mobility pro graphics) everything ran great under win98. so i know it's
not the hardware involved.
the thing i believe i need to overcome is dma.  in win98 i was able to
enable dma.  back in linux, hdparm -d1 /dev/hde (the same command i use on
the desktop computer to enable dma on the dvd drive) chokes.  hdparm
doesn't like the pcmcia-ide crossover.  i also tried adding
append="ide2=dma" to /etc/lilo.conf, but that had no perceivable affect
(nor did it display or log (that i could find) any error).

there are a couple of hints that may help me resolve this issue.

1. i'm pretty sure dma is the answer (i need dma for this machine/drive
combo in windows and dma is called for on my desktop system to play dvds)
2. in win98 you don't enable dma for the drive (the usual device manager
way), but for the pcmcia interface using a software utility that comes
with the drive.

there is a section in /etc/pcmcia/ide.conf that says

OPTS=""

i've been googling in vain hoping to find an entry for OPTS that says _dma
on_ or something.
i figure there has got to be a way to enable dma for this sucka.

any help, guesses, or leads in the right direction would be greatly
appreciated.

d.