From owner-freebsd-current Tue Jan 5 02:24:53 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id CAA26980 for freebsd-current-outgoing; Tue, 5 Jan 1999 02:24:53 -0800 (PST) (envelope-from owner-freebsd-current@FreeBSD.ORG) Received: from nlsystems.com (nlsys.demon.co.uk [158.152.125.33]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id CAA26972 for ; Tue, 5 Jan 1999 02:24:50 -0800 (PST) (envelope-from dfr@nlsystems.com) Received: from localhost (dfr@localhost) by nlsystems.com (8.9.1/8.8.5) with SMTP id KAA11317; Tue, 5 Jan 1999 10:24:33 GMT Date: Tue, 5 Jan 1999 10:24:33 +0000 (GMT) From: Doug Rabson To: Garrett Wollman cc: Warner Losh , Bill Paul , current@FreeBSD.ORG Subject: Re: bus_space_foo and bus_dmamap_foo In-Reply-To: <199812312058.PAA07052@khavrinen.lcs.mit.edu> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, 31 Dec 1998, Garrett Wollman wrote: > < said: > > > It was my understanding from talking to Justin that these areas were > > basically orthoginal. busspace and busdma are used to talk to the > > hardware, while DFR's new bus stuff is more a configuration thing > > rather than talking to the actual hardware. > > How you talk to the hardware depends on where it is in the > configuration graph. > > > How do you view this integration? I'm confused... What needs to be > > integrated? > > When you activate a memory or I/O resource, the appropriate magic > should happen such that included in the stuff you get back is > something which can be used to access that resource quickly. Stuff > like bus_space_alloc should be handled by the bus driver in > coordination with the resource manager. (It should be implemented as > a method call on the device's parent, so that it has all the necessary > context pre-computed.) I think that this is the right approach. The interface for PCI busses should have methods to manage the various device resources and these will be able to provide bus_space handles as necessary. The resources should not need to be mapped directly by the pci driver. I'm currently prototyping the new PCI interface (or I will be as soon as I can get that wretched sysinstall program working properly on the alpha) and I'll add something like this. Are there any manpages for bus_space and bus_dma in NetBSD which we can take? -- Doug Rabson Mail: dfr@nlsystems.com Nonlinear Systems Ltd. Phone: +44 181 442 9037 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message