From owner-freebsd-current@FreeBSD.ORG Mon Jan 10 03:31:31 2005 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2E66016A4CE for ; Mon, 10 Jan 2005 03:31:31 +0000 (GMT) Received: from pooker.samsco.org (pooker.samsco.org [168.103.85.57]) by mx1.FreeBSD.org (Postfix) with ESMTP id B527943D3F for ; Mon, 10 Jan 2005 03:31:30 +0000 (GMT) (envelope-from scottl@freebsd.org) Received: from [192.168.254.11] (junior-wifi.samsco.home [192.168.254.11]) (authenticated bits=0) by pooker.samsco.org (8.12.11/8.12.10) with ESMTP id j0A3Yo65037406; Sun, 9 Jan 2005 20:34:50 -0700 (MST) (envelope-from scottl@freebsd.org) Message-ID: <41E1F6AD.9040704@freebsd.org> Date: Sun, 09 Jan 2005 20:29:49 -0700 From: Scott Long User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.7.2) Gecko/20040929 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "Wilkinson, Alex" References: <20041223123621.GB17515@eddie.nitro.dk> <41CADACC.9050607@freebsd.org> <20050106131327.GE801@zaphod.nitro.dk> <20050106.134852.41638084.imp@harmony.village.org> <41DDC29F.9000002@freebsd.org> <20050110015842.GA24213@squash.dsto.defence.gov.au> In-Reply-To: <20050110015842.GA24213@squash.dsto.defence.gov.au> X-Enigmail-Version: 0.86.1.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, hits=0.0 required=3.8 tests=none autolearn=no version=2.63 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on pooker.samsco.org cc: freebsd-current@freebsd.org Subject: Re: pci powerstate related: aac(4) broken on Perc 3/Di on -CURRENT X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 10 Jan 2005 03:31:31 -0000 Wilkinson, Alex wrote: > 0n Thu, Jan 06, 2005 at 03:58:39PM -0700, Scott Long wrote: > > > >It should be noted that WinXP tried to get fancy in a similar way with > >automatic powerdown of devices, and broke these PERC devices in a > >similar way. Due to restrictions of the MS driver framework, the only > >solution that Adaptec could use was to modify the firmware to make the > >bridge be opaque. This solved the issue of the OS seeing devices that > >belong to the firmware, but made it impossible to run the controller in > >split-channel mode, where one channel is for RAID and the other channel > >is pure SCSI. > > > Scott, what is meant by "...to make the bridge be opaque." ? > > - aW > A PCI-PCI bridge is opaque when it is set to not forward PCI config cycles across the bridge. In other words, the host CPU cannot see any devices past the first side of the bridge. However, normal data cycles work, so things like DMA work. This is incredibly useful for segregating the PCI hierarchy into sub-domains that are only visible within a specific scope, but allow data to travel across the domain boundaries. Many RAID cards are set up this way. Scott