From owner-freebsd-arch Mon Dec 17 18:36:23 2001 Delivered-To: freebsd-arch@freebsd.org Received: from khavrinen.lcs.mit.edu (khavrinen.lcs.mit.edu [18.24.4.193]) by hub.freebsd.org (Postfix) with ESMTP id 14D2737B41B for ; Mon, 17 Dec 2001 18:36:20 -0800 (PST) Received: (from wollman@localhost) by khavrinen.lcs.mit.edu (8.11.4/8.11.4) id fBI2aHM39997; Mon, 17 Dec 2001 21:36:17 -0500 (EST) (envelope-from wollman) Date: Mon, 17 Dec 2001 21:36:17 -0500 (EST) From: Garrett Wollman Message-Id: <200112180236.fBI2aHM39997@khavrinen.lcs.mit.edu> To: imp@harmony.village.org Subject: Re: Please review: changes to MI bus code for sparc64 In-Reply-To: <200112180212.fBI2CUM81074@harmony.village.org> References: <20011213211544.A4747@crow.dom2ip.de> <20011213192033.A871@crow.dom2ip.de> <200112131901.fBDJ1hl02003@mass.dis.org> <20011213211544.A4747@crow.dom2ip.de> Organization: MIT Laboratory for Computer Science Cc: arch@FreeBSD.org Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In article <200112180212.fBI2CUM81074@harmony.village.org> you write: >I don't understand the difference between boundary and alignment. A boundary is a locus which an allocation must not cross. Consider, for example, the crufty old ISA DMA hardware: 16-bit transfers need only 16-bit alignment, but must not cross a 64-kbyte ``page'' boundary, because the address-generation logic was kluged out of a 16-bit DMA controller and an 8-bit latch. -GAWollman -- Garrett A. Wollman | O Siem / We are all family / O Siem / We're all the same wollman@lcs.mit.edu | O Siem / The fires of freedom Opinions not those of| Dance in the burning flame MIT, LCS, CRS, or NSA| - Susan Aglukark and Chad Irschick To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message