Subject: Re: LANCE (Am7990) DMA
To: None <email@example.com,>
From: Michael C. Richardson <firstname.lastname@example.org>
Date: 10/11/1998 13:35:14
>>>>> "Matthias" == Matthias Drochner <email@example.com> writes:
Matthias> You should make sure that the common code does compile
Matthias> even if the platform doesn't implement the bus_dma interface.
Matthias> Perhaps some words to the code structure which got one more
Matthias> dimension since I split the am7990 and am79900 code:
Matthias> am7990 is the old LANCE chip with 16-bit descriptors (and
Matthias> 24-bit addressing capability). This driver part is used by all
One thing that confused me about the 7990 stuff. When they are present on
VME/obio sun3/sparc'en, I know that they do DVMA. As far I can tell, they
use a rather small buffer of DVMA. (On sbus, there is an lebuffer, which
I assume they are restricted to.)
Matthias> So the "direct DMA" capability should be orthogonal to the
Matthias> existing features. This looks quite like a challenge, but it is
Matthias> certainly worth a try.
:!mcr!: | Network and security consulting/contract programming
Michael Richardson | Firewalls, TCP/IP and Unix administration
ON HUMILITY: To err is human, to moo bovine.