Miata MX5 and 64 bit gigabit ethernet

[Andrew Gallatin]

Fred Clift writes:

 > If the card does dma, then it will be unlikley to work.  I dont know that
 > Gigabit ethernet existed when miatas were new, and hence, DEC wouldn't

Please get a clue or stop spreading FUD.  

The DMA bug occurs when crossing a page (8K) boundary using scatter/gather
DMA READs.  FreeBSD doesn't even use scatter/gather for anything but
ISA cards at the moment.  Most GigE cards are not ISA ;)

For what its worth,  we used Alteon Tigon II Gigabit nics on our
Miatas back when the hardware was current and 4.0 was -CURRENT.

Even if it works, don't expect great performance.  As best as I can
remember, we never managed to get much more than 500Mb/sec throughput,
even with jumbo frames.  This is partly because the Miata's PCI bus /
memory system really sucks by modern standards and it can't get
anywhere near the 250MB/sec theoretical PCI max...


Drew