K 10
svn:author
V 5
wpaul
K 8
svn:date
V 27
2003-09-20T21:18:27.000000Z
K 7
svn:log
V 720
Remove the dual-address cycle stuff. DAC is used to allow a bus master
device to access 64-bit addresses from a 32-bit PCI bus. While the
RealTek manual says you can set this bit and the chip will perform
DAC only if you give it a DMA address with any of the upper 32
bits set, this appears not to be the case. If I turn on the DAC
bit, the chip sets the 'system error' bit in the status register
when I to do a DMA on my Athlon test box with 32-bit PCI bus (VIA
chipset) even though I only have 128MB of physical memory, and thus
can never give the chip a 64-bit address.

Obviously, I can't just set it and forget it, so until I figure
out the right rule for when it's safe/necessary to enable it, keep
it turned off.

END