> Shaw Carruthers wrote:
> >
> > > > a) Some BIOSes turn DMA on when they shouldnt
> > >
> > > Rare, and Linux makes its own decision anyway.
> >
> > My TX97-E bios starts up my QUANTUM FIREBALL ST2.1A as UDMA 2, but linux
> > 2.1.66 sets DMA off. I have to turn it on with hdparm. I am not clear why
> > linux does this. How does linux make its decision?
>
> Linux currently does not include full support for UDMA
> (need to add CRC checking and error handling to do a proper job),
> so it does not use DMA by default in your case.
Wow, wait a sec here..
With proper udma support will linux have to compute a crc32 of every block
transfered???? Are there other stupid things like this with ide? No wonder
IDE is such a damn cpu eater!