Date: Sat, 20 Sep 2003 14:18:27 -0700 (PDT) From: Bill Paul <wpaul@FreeBSD.org> To: src-committers@FreeBSD.org, cvs-src@FreeBSD.org, cvs-all@FreeBSD.org Subject: cvs commit: src/sys/dev/re if_re.c Message-ID: <200309202118.h8KLIR7u023193@repoman.freebsd.org>
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wpaul 2003/09/20 14:18:27 PDT
FreeBSD src repository
Modified files:
sys/dev/re if_re.c
Log:
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.
Revision Changes Path
1.10 +2 -4 src/sys/dev/re/if_re.c
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