CD-RW/DVD-ROM Combo

[Charles Steinkuehler]

Duane Attaway wrote:

> On Tue, 23 Dec 2003, Charles Steinkuehler wrote:
> 
>> Is it possible to use DMA with a 2.4 kernel and ide-scsi?  I tried to
>> get this going, but it seems stuck in PIO mode, and I typically can't
>> burn over 8x w/o making 'coasters'.
> 
> I'm using ide-scsi with a 2.4 kernel.  DMA works for me!  You are checking 
> the DMA for the IDE interface, not the scsi emulation layer, right?

<snip>

I crawled through the RH init scripts, and it turns out that was my 
problem.  The RedHat scripts only apply the /etc/sysconfig/harddisks 
settings to *DISK* devices (cat /proc/ide/hd?/media = "disk"), not CDROM 
(or other) devices.  Copying the harddisks file to the undocumented 
harddisk<device> file (which causes the init scripts to apply the 
settings regardless of the media type) has solved my problem, and DMA 
appears to be working (at least according to hdparm and proc).

Next up, a real world test of burining a CD at more than 8x!

-- 
Charles Steinkuehler
charles at steinkuehler.net