Announcement

Collapse
No announcement yet.

fglrx, 64bit linux and sb600 dma issue

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • fglrx, 64bit linux and sb600 dma issue

    Hi,
    I would like to elaborate a little about a problem I've been having regarding the installation of fglrx drivers on my system with 64bit linux, hoping that someone of the devs will respond . My gfx is HD2600XT, and my motherboard asrock ALiveXFire-eSATA2 (which has SB600 southbridge).

    Here is what I have tried in more easily understandable manner:
    - 64bit linux + 2GB RAM + fglrx = runs Ok.
    - 64bit linux + 4GB RAM + fglrx = X doesn't start, blocks before login screen.
    - 64bit linux + 4GB RAM + radeon | radeonhd = runs Ok.
    - 32bit linux + 4GB RAM + fglrx = runs Ok, of course ram limited to 3.2GB.

    I have tried with: openSUSE 11.1, Ubuntu 8.10 and Sabayon 4.
    I have read that SB600 reports that it supports 64bit DMA, but it doesn't, and this is fixed in the ahci driver. MSI and Gigabyte fixed this in a BIOS update, but not ASRock.
    I beleive that the problem is that somehow fglrx expects 64bit DMA in 64bit operating system, without testing for chipset support. I am not sure how radeon | radeonhd have this solved. Maybe someone could test this, or report this same issue.
    Thanks in advance for any help.

  • #2
    Btw. there is a server kernel on ubuntu which allows use of up to 64 gb ram in 32 bit mode.

    Comment


    • #3
      Thanks for responding.
      But I don't think this is a good solution for this problem. If I was not clear in my previous post I appologise.
      I would like to use 64bit linux with fglrx, but this is not yet possible. However it is possible with radeon | radeonhd, which shows that there is a solution for fglrx also.
      I think that this bug in fglrx should be corrected anyway, instead of everyone like me with sb600 and Radeon gfx to be forced to use 32bit OS with PAE, in order to get good 3D support.
      I beleive that the fix will not be too much complicated. It may be as simple as testing for SB600, and expecting 32bit DMA in 64bit fglrx, so that the gfx drivers may be allowed to allocate any needed system memory.
      Again thanks for everyones help.

      P.S. sorry if my english is bad

      Comment


      • #4
        Maybe a bios update fixes it.

        Comment


        • #5
          As I mentioned (in the first post) there is no bios fix. I also mentioned that there is a fix in the ahci driver of the kernel:
          http://www.mail-archive.com/linux-id.../msg06694.html.
          With which radeon and radeonhd drivers work ok in 64bit linux.
          But not fglrx, which makes this fglrx bug, IMO.

          Comment


          • #6
            With which radeon and radeonhd drivers work ok in 64bit linux.
            But not fglrx, which makes this fglrx bug, IMO.
            The radeon and radeonhd drivers may simply work because they don't yet have 3D acceleration on 6xx/7xx parts, and therefore are not placing any serious demands on memory or DMA. It may be a year or more before the 3D drivers get to the point where they are putting the same kind of demands on the system.
            Test signature

            Comment


            • #7
              But fglrx in 32bit linux works well with 3D, using 32bit DMA.
              The trouble is that fglrx doesn't work with 32bit DMA in 64bit linux, because it doesn't detect it as such, which is shown by blocked X during startup, before login screen appears (at this stage only thing to do is manual restart, as the system is completely blocked).
              At this point I can't get even 2D with fglrx/64bit, much less 3D.

              Comment


              • #8
                Isn't it funny that this bug exists on pure AMD/ATI hardware

                Comment


                • #9
                  I don't get the connection. AFAIK there is nothing in the GPU or the GPU driver which uses a SB DMA controller. All the "DMA transfers" to/from the GPU are what used to be called "bus mastering", where the peripheral (in this case the GPU) supplies the address directly.

                  Why do you think that 64-bit issues with fglrx are related to sb600 dma, other than both being 64-bit issues ?
                  Test signature

                  Comment


                  • #10
                    Similar problem

                    Originally posted by Kizo View Post
                    But fglrx in 32bit linux works well with 3D, using 32bit DMA.
                    The trouble is that fglrx doesn't work with 32bit DMA in 64bit linux...
                    I have a motherboard with the SB600 (Biostar TA770 A2+), and similar problems with 64 bit Linux, & fglrx (on an AMD x1550). Works fine with radeonhd driver. Works fine with either driver using 32 bit Linux.
                    Last edited by ktraglin; 18 February 2009, 12:31 PM.

                    Comment

                    Working...
                    X