[3667] in linux-net channel archive
Re: new lance patch
daemon@ATHENA.MIT.EDU (Thomas Bogendoerfer)
Sat Jul 13 12:12:59 1996
From: Thomas Bogendoerfer <tsbogend@bigbug.franken.de>
To: becker@cesdis1.gsfc.nasa.gov (Donald Becker)
Date: Fri, 12 Jul 1996 22:31:01 +0200 (MET DST)
Cc: gpg109@rsphy1.anu.edu.au, MC3641@mclink.it, linux-net@vger.rutgers.edu
In-Reply-To: <Pine.SUN.3.91.960712100738.24030B-100000@cesdis1> from "Donald Becker" at Jul 12, 96 10:18:44 am
Reply-To: tsbogend@bigbug.franken.de
> Overall, I didn't think the win was big enough to justify releasing
> another driver. But if someone else is maintaining it...
the reason why I changed lance.c to support the 32bit mode of
the PCnet32 family, was the fact that you _can't_ use an ISA
busmaster in an _Alpha_ machine at the moment (there is a way to
do it, but nobody has written the code for it yet).
The problem with Linux/Alpha and ISA busmaster (and PCI chips used
in an ISA busmaster compatible way) is the fact, that there is no
mapping from the ISA address space to memory for DMA cycles. So
when you try to use the PCnetPCI chip with only 24bit addresses
you will never be able to access memory (to be correct there
is a way, but it's more a dirty hack than a real solution. And
it doesn't make life easier).
Thomas.
--
See, you not only have to be a good coder to create a system like Linux,
you have to be a sneaky bastard too ;-)
[Linus Torvalds in <4rikft$7g5@linux.cs.Helsinki.FI>]
