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Date: Sun, 7 May 1995 14:49:52 +1000
From: Bruce Evans <bde@zeta.org.au>
Message-Id: <199505070449.OAA02283@godzilla.zeta.org.au>
To: julian@ref.tfs.com, mtaylor@gateway.cybernet.com
Subject: Re: lance Ethernet and > 16 Mb RAM failure
Cc: hackers@FreeBSD.org
Sender: hackers-owner@FreeBSD.org
Precedence: bulk

>> I'm installing 2.0-950412-SNAP on a new system.  I've never used the 'lnc'
>> ethernet drivers before, and I'm having difficulty getting them stable on a
>> system with more than 16 Mb of RAM.
>> 
>looks as if the bounce buffer code in the dma
>using routines for non master dma, is broken, 
>OR maybe they are not using it correctly....

>It sould use it's DMA in much the same way as the floppy driver does, 
>so that it can guarantee that the DMA will go to a buffer < 16MB
>but this may not be the case..

It isn't the case.  The TODO list at the start of if_lnc.c says bounce
buffer support will be needed for dma'ing to mbufs above 16MB.

Bruce