[mythtv] hdparm

Chris Liscio mythtv-dev@snowman.net
Fri, 13 Dec 2002 09:35:59 -0500

> wtf is going on??  what am I missing?

It could be a few things, Rob.

First off, your kernel might not have support compiled in for your
particular chipset.  I'm not sure what chipset you're using, but you
definitely have to compile settings into your kernel to get full support for
the UDMA controller on your mobo.

For me, I have a VIA KT133 and I did the following (paraphrased from

I did a 'make menuconfig' in the kernel, and went to 'ATA/IDE/etc support',
enabled 'ATA/IDE/etc support', and then went into the next menu item (device
support, I think).  Then, I turned on 'enable DMA only for hard disks', and
below that chose the chipset I'm using (I think for me it was VIA82Cxxx or

After enabling that, DMA was on by default on my drive, as expected.

Unfortunately, I don't think this comes in module form, so you will
*definitely* need a kernel recompile if support wasn't added by default.
Obviously, in case you have an unsupported dma chipset, you might be SOL.

Hope this helps,