From owner-freebsd-current Sun Jul 30 08:27:06 1995 Return-Path: current-owner Received: (from majordom@localhost) by freefall.cdrom.com (8.6.11/8.6.6) id IAA12083 for current-outgoing; Sun, 30 Jul 1995 08:27:06 -0700 Received: from localhost.cdrom.com (localhost.cdrom.com [127.0.0.1]) by freefall.cdrom.com (8.6.11/8.6.6) with SMTP id IAA12070 ; Sun, 30 Jul 1995 08:27:02 -0700 Message-Id: <199507301527.IAA12070@freefall.cdrom.com> X-Authentication-Warning: freefall.cdrom.com: Host localhost.cdrom.com didn't use HELO protocol To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) cc: terry@cs.weber.edu (Terry Lambert), freebsd-current@freebsd.org, babb@freebsd.org Subject: Re: Update on my aic driver problems In-reply-to: Your message of "Sun, 30 Jul 95 11:34:34 +0200." <199507300934.LAA23968@uriah.heep.sax.de> Date: Sun, 30 Jul 1995 08:27:01 -0700 From: "Justin T. Gibbs" Sender: current-owner@freebsd.org Precedence: bulk >As Terry Lambert wrote: >> >> > The aic chip is actually an AIC 6260, and the `aic' driver isn't very >> > clear about this, but it looks like it would only support AIC 6360's. :-( >> >> The 6260 doesn't support scatter/gather, I believe. >> >> > Does anybody know what's the difference, and if it would be allot of >> > work to hack it? By now, all i get is ``sd0(aic0:0:0) timed out'' >> > when sysinstall tries to find the drive(s), even though the driver has >> > been properly probing the chip and announced the disk drive. >> >> I don't know how you'd hack it onto a chip that doesn't support it. >> >> 8-). > >Hmm, well. Scatter/gather is a required feature for FreeBSD, ain't >it? Hmm, pity. Perhaps i could find an IDE disk for it plus a spare >old IDE adaptor. No, its not. What you'll have to do is allocate a 64k contiguous staging buffer and do the transaction from there. Since scatter/gather is handled at the controller driver layer, the rest of the SCSI system makes no assumptions about it use... it just happens that most transactions are to buffers that are not physically contiguous, so if you use DMA, you must have the staging buffer. It should be possible to get it to work, but the performance won't be that great. > >-- >cheers, J"org > >joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ >Never trust an operating system you don't have sources for. ;-) -- Justin T. Gibbs =========================================== Software Developer - Walnut Creek CDROM FreeBSD: Turning PCs into workstations ===========================================