From owner-freebsd-hackers Tue Oct 22 12:26:16 1996 Return-Path: owner-hackers Received: (from root@localhost) by freefall.freebsd.org (8.7.5/8.7.3) id MAA24832 for hackers-outgoing; Tue, 22 Oct 1996 12:26:16 -0700 (PDT) Received: from alpo.whistle.com (alpo.whistle.com [207.76.204.38]) by freefall.freebsd.org (8.7.5/8.7.3) with ESMTP id MAA24825 for ; Tue, 22 Oct 1996 12:26:13 -0700 (PDT) Received: from current1.whistle.com (current1.whistle.com [207.76.205.22]) by alpo.whistle.com (8.7.6/8.7.3) with SMTP id MAA10255; Tue, 22 Oct 1996 12:25:34 -0700 (PDT) Message-ID: <326D1F25.ABD322C@whistle.com> Date: Tue, 22 Oct 1996 12:23:17 -0700 From: Julian Elischer Organization: Whistle Communications X-Mailer: Mozilla 3.0b6 (X11; I; FreeBSD 2.2-CURRENT i386) MIME-Version: 1.0 To: Alexander Seth Jones CC: hackers@freefall.freebsd.org Subject: Re: DMA and autoinitialize References: <326CD424.7085@ctron.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-hackers@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk Alexander Seth Jones wrote: > >What makes things tough is that > the interrupt on the card is not tied to DMA in hardware, what DOES that mean? if it's an isa device, does it have DMA termination enabled? (LAST_CYCLE AND'd with DMAREQ) => IRQ > so I have to > poll the DMA controller periodically to see how many bytes I can > transfer over to an internal buffer. can be done.. a timeout(1) can be used to simulate an interrupt every 10 mSec > > I looked through all the drivers and didn't see anybody even doing any > autoinitialization, nor did I see a routine to periodically grab stuff > from the DMA buffer (2.1.5-RELEASE) Does such a routine exist? or will > I have to write one? or can someone suggest another way to approach > this? describe the h/w more thouroughly.. > > Thanks. > > -- > Alex Jones | ajones@ctron.com > Cabletron Systems, Inc. > Durham, NH USA 03824