[LinuxBIOS] #84: grub2 can boot linux from IDE disk

Peter Stuge peter at stuge.se
Fri Jul 13 01:49:18 CEST 2007

On Thu, Jul 12, 2007 at 10:19:30PM +0200, Patrick Georgi wrote:
> Peter Stuge wrote:
> > The OpenBIOS driver is very nice and neat, but not as featureful
> > as ADVDRVR which even does DMA.
> I'm pretty much planning to use openbios' (axboe's) driver.

Are the grub2 fs drivers already written to do multiblock reads from
the block devices btw? This is pretty important as seen in FILO.
(Admittedly a design decision above the IDE driver.)

> I also doubt that DMA is useful in the boot environment, and I'd
> like to keep complexity down.

I think DMA would be nice. It can make a difference already with a
few megabytes which isn't very uncommon for a complete kernel and
easily reached with a ramdisk or xen.

The complexity is indeed the tradeoff, but it has been suggested
that IDE DMA need not be all that complex.

Perhaps worthwhile to have a look at what MINDRVR does? 975 loc


More information about the coreboot mailing list