Re: Unable to enable IDE harddisc DMA on VIA KT 880, VIA VT 8237 chipset

["J. Grant" <jg@jguk.org>]

[Please include my email address in any replies]

Hi,

[...]
> > Check that you do not load ide-generic at boot time (or not at all)
> > but the specific driver for your chipset.
>
> To this specific chipset the right driver looks like 'via82cxxx'.

Thanks for the tips Otavio Salvador and Goswin von Brederlow.

This is the contents of my /etc/modules
(the initrd does not load ide-generic or via82cxxx)

floppy
ide-disk
#ide-generic
via82cxxx
ide-cd
psmouse
#sd_mod
nvidia

I was the one who commented out ide-generic, and added via82cxxx.

Unfortunately now /dev/hda (IDE DVD-Writer) and /dev/hdc1 (that drive
without DMA enabled) are not present.  I did notice that via82cxxx was
in use when ide-generic was loaded before my reboot.  I wonder what else
I need to change to get back my /dev/hd* ?


now2g:/dev# ll hd*
ls: hd*: No such file or directory

now2g:/dev# modprobe ide-generic

now2g:/dev# ll hd*
brw-rw----  1 root floppy  3, 0 2005-08-01 22:15 hda
brw-rw----  1 root disk   22, 0 2005-08-01 22:15 hdc
brw-rw----  1 root disk   22, 1 2005-08-01 22:15 hdc1

# hdparm -d 1 /dev/hdc

/dev/hdc:
 setting using_dma to 1 (on)
 using_dma    =  1 (on)


$ lsmod |grep ide
ide_cd                 42528  0
cdrom                  40284  1 ide_cd
ide_generic             1472  0
ide_disk               19264  2
ide_core              138724  4 ide_cd,ide_generic,via82cxxx,ide_disk
[now3d@now2g dev]$ lsmod |grep via82cxxx
via82cxxx              13980  1
ide_core              138724  4 ide_cd,ide_generic,via82cxxx,ide_disk


# hdparm -t /dev/hdd

/dev/hdd:
 Timing buffered disk reads:   94 MB in  3.13 seconds =  29.99 MB/s



So is the solution to load via82cxxx and then ide-generic? it would seem
so.. I revised my /etc/modules to be like this:

floppy
ide-disk
via82cxxx
ide-generic
ide-cd
psmouse
#sd_mod
nvidia

Now everything works fine! :) Thanks for the help.  I wonder if this
could be detected by debian-installer and configured correctly by
default..? (My install is not latest.. so this might have been fixed)

Kind regards
JG