From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.gmx.net (mail.gmx.de [213.165.64.20]) by ozlabs.org (Postfix) with SMTP id 7D740679E6 for ; Sat, 11 Mar 2006 00:31:05 +1100 (EST) Date: Fri, 10 Mar 2006 14:31:01 +0100 (MET) From: "Gerhard Pircher" To: linuxppc-dev@ozlabs.org,debian-powerpc@lists.debian.org MIME-Version: 1.0 References: <31042.1141997321@www088.gmx.net> Subject: Re: Unmapping pages from the linear addressing without HIGHMEM support Message-ID: <7457.1141997461@www088.gmx.net> Content-Type: text/plain; charset="iso-8859-1" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , > --- Ursprüngliche Nachricht --- > Von: Dan Malek > An: "Gerhard Pircher" > Kopie: debian-powerpc@lists.debian.org, linuxppc-dev@ozlabs.org, Benjamin > Herrenschmidt > Betreff: Re: Unmapping pages from the linear addressing without > HIGHMEM support > Datum: Fri, 10 Mar 2006 07:59:33 -0500 > > On Mar 10, 2006, at 4:09 AM, Gerhard Pircher wrote: > > > That would mean I cannot reuse the code in dma-mapping.c, right? > > Sure you can. All you need to do is turn of BAT mapping, which > is as easy as using the 'nobats' command line parameter and > all of this code should just work for you. Yes, that was the solution I would have used. The other solution is to reserve a physical memory area for DMA operations that is not mapped by the BATs (AFAIU nor by any page tables setup by the kernel). Therefore I doubt that I can simply reuse the dma-mapping.c code for the latter approach!? Do I mix something up here? > > ... but I guess I have to setup my own page table for the reserved > > DMA memory area and implement my own alloc_pages() function!? > > No, that's already done for you behind all of these functions. But only, if the whole BAT mapping is killed, right? Thanks! Gerhard -- "Feel free" mit GMX FreeMail! Monat für Monat 10 FreeSMS inklusive! http://www.gmx.net