I wrote about a week or so ago about switching DMA modes on the HPT370
I've been fiddling and have found something odd.
If I compile a kernel without the 'HPT370' option in the IDE/ATA config,
the machine starts okay, and after turning DMA on, the drive fetches about
21.5MB/s. hdparm tells me the drive/chipset is in udma4. I can change the
DMA mode without crashing, although if I change out of udma4, I can't set
it back to udma3/udma4 (states that the mode is not functional).
If I compile a kernel /with/ the 'HPT370' option in the IDE/ATA config, the
machine starts okay, turns DMA mode on itself, and puts the drive into
udma2. The drive fetches 17.4MB/s. If I change DMA mode, the machine crashes.
No kernel panic, nothing - just completely dead.
Rob off list/ng replies: [email protected]
Not to worry I will make a permanent fix to require Chipset code for
funtionallity; therefore, the confusion of modes will be completely
CTO Timpanogas Research Group
EVP Linux Development, TRG
Linux ATA Development