Well, better late than newer, but things has been hectic
around here, sorry for the long delay.
DMA support has been added to the ATA disk driver.
This only works on Intel PIIX3/4, Acer Aladdin and Promise controllers.
The promise support works without the BIOS on the board,
and timing modes are set to support up to UDMA speed. This
solves the problems with having more than one promise controller
in the same system.
There is support for "generic" DMA, that might work on other
controllers, but now you have been warned :)
More chipset specific code will come soon, I have to find testers
with the approbiate HW, more on that when I have it ready.
The system now uses its own major numbers, please run MAKEDEV
with the devices you need (ad?, acd?, afd?, ast?).
For now the disk driver will also attach to the old wd major
so one can at least boot without this step, but be warned, this
will eventually go away. The bootblocks will have to be changed
before one can boot directly from an "ad" device though.
Fixed problems:
All known hang problems should be solved
The probe code has been sligthly changed, this should solve
the reports I have lying around (I hope).
Hangs when accessing ata & atapi device on the same channel simultaniously.
A real braino in ata_start caused this, fixed.
As usual USE AT YOUR OWN RISK!!, this is still pre alpha level code.
Especially the DMA support can hose your disk real bad if anything
goes wrong, agaiin you have been warned :)
But please tell me how it works for you!
Enjoy!
-Søren
