Find the answer to your Linux question:
Results 1 to 7 of 7

Thread: Enabling DMA

Enjoy an ad free experience by logging in. Not a member yet? Register.
  1. #1

    Enabling DMA


    I have installed gentoo...everything works fine....

    Only problem i am really having is getting DMA to work, and its really slowing down the system! Ive treid everything i can think of, so i would appriciate someone giving advice as to what exactly i need to do.

    Heres what i have done so far:

    Ive done lspci
    0000:00:11.1 IDE interface: VIA Technologies, Inc. VT82C586A/B/VT82C686/A/B/VT823x/A/C PIPC Bus Master IDE (rev 06)
    and i think thats the IDE controller, right?

    So I have recompiled my kernel with a * next to that device driver...

    hdparm says this about hda
    hdparm /dev/hda
     multcount    = 16 (on)
     IO_support   =  0 (default 16-bit)
     unmaskirq    =  0 (off)
     using_dma    =  0 (off)
     keepsettings =  0 (off)
     readonly     =  0 (off)
     readahead    = 256 (on)
     geometry     = 65535/16/63, sectors = 81964302336, start = 0
    and if i try and enable dma I get this...
    hdparm -d 1 /dev/hda
     setting using_dma to 1 (on)
     HDIO_SET_DMA failed: Operation not permitted
     using_dma    =  0 (off)
    So it just wont work.....

    I also have mandrake 10.1 installed on this system....DMA works fine there...

    I even tried using the .conf from the mandrake kernel and compiled it in gentoo and used that instead of my smaller gentoo kernel...and it still didnt work. Im back using the gentoo kernel now.

    So what do I need to do? i dont see what Im missing!

    Thanks for your help.

  2. #2
    Linux Engineer
    Join Date
    Mar 2005
    I haven't enabled DMA here so I dunno what the problem is, but just to make sure: you were root, right?

  3. #3
    Yes i was root.

    I just wanna know which device drivers I need other than VIA82CXXX chipset support enabled in my kernel, i guess i must have one missing or somthing....

    Also, should these be built in or modulerised?? currently, these are built in[*] in menuconfig.

  4. $spacer_open
  5. #4
    Linux Engineer
    Join Date
    Mar 2005
    Myself I prefer built-in, the only reason to use modules is if you're building a generic kernel or a livecd, or if you have a driver which you only use once in a while and you beleve slows down the kernel. Use it built in, myself I only modulize alsa-drivers to make it compatible with alsaconf (unless the times I'm using OSS )

  6. #5
    I was being silly,

    I accidentaly forgot that my /boot was a seperate partition, and then copied all my kernels with dma support to the /boot dir not partition....its all working now!

  7. #6
    Just Joined!
    Join Date
    Aug 2005

    A follow up

    I have exactly the same setup and problem.
    When you say that you copied your kernels from the boot partition to
    the boot directory, could you please explain why you did this and what
    it accomplished?

    I have /boot on /dev/hda8 and / on /dev/hda9, but /dev/hda8 is mounted
    as /boot. Why is this any different than having the kernel in the /boot that
    is part of /dev/hda9? Isn't the one on /dev/hda9 hidden?


  8. #7
    Linux Engineer
    Join Date
    Mar 2005
    If you mount the /boot partition to /boot, the content of the existing folder /boot on the /-partition is unaccessable, and you instead access the data on the /boot partition.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts