cvs commit: src/sys/dev/re if_re.c

[Bill Paul]

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