Oh, just another note, mine seems to be fine with DMA:
kernel config line is
cd2             at atapibus1 drive 0 flags 0x0000
and dmesg says
cd2 at atapibus1 drive 0: <MATSHITA CD-RW CW-7585, , 1.04> type 5 cdrom
removable
cd2: 32-bit data port
cd2: drive supports PIO mode 4, DMA mode 2
cd2(pciide0:1:0): using PIO mode 4, DMA mode 2 (using DMA data transfers)

-Sean

On Tue, May 14, 2002 at 03:36:58PM -0400, Sean Davis wrote:
> > 
> > cd0(pciide0:1:0): illegal request, data = 00 00 00 00 64 00 00 00 00 00
> > cd0: dos partition I/O error
> I see these all the time when doing stuff with cds, burning, playing, etc. I
> think mounting too, but I don't remember.
> 
> 
> > wdc_atapi_intr: warning: reading only 1 of 2 bytes
> > wdc_atapi_intr: warning: reading only 1 of 2 bytes
> never seen these before, however.
> 
> I think the first ones can be safely ignored; however the second ones seem
> to say something odd is going on.
> 
> -Sean
> 
> -- 
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