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All I have available right now are three patches for the Linux kernel.  They enable Bus Master DMA mode 2 support for VIA's VP2/97 chipset (I believe they also work with all the Apallo series and the AMD-640) while removing the unknown PCI device warnings from the kernel when it starts up.  The VP2/97 is found most commonly on FIC's PA-2007 and PA-2011; the VP3 (also from the Apallo series) is on FIC's PA-2012; and the AMD-640 is on Shuttle's Hot-603.   Please Email me if you know of any other chipsets these patches will (not) work with.

Update:   I am starting a list of chipsets and motherboards that users have reported the patch to work with.   The list follows:

To patch your kernel to enable BM DMA mode 2 support, follow these steps:

  1. Download (shift left click) the appropriate patch for your kernel:

  3. Apply the patch to your kernel:

  5. Recompile your kernel with Triton chipset support enabled.

  7. Enjoy your new kernel and faster disk access (after using hdparm, see below)!  :)

Please note that if the patches do not correctly apply you may need to get unpatched sources from ftp.kernel.org.   Some distributions (RedHat 4.2, ect.) include kernel sources that are patched versions of the official distributions.

Please also note that once your kernel supports DMA, you must enable it yourself with hdparm, which you should already have installed on your system.   As root, running hdparm -c1 -d1 -X34 /dev/hd? for each drive that supports DMA mode 2 would be a g ood start (-c1 enables 32 bit access, -d1 enables dma access, and -X34 sets dma access to mode 2).   You can add more switches to hdparm as long as your system stays stable.   Once you know all the settings you want for each drive, you should add a hdparm line for each DMA mode 2 drive you have to /etc/rc.d/rc.local

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