Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262206AbVDFN1V (ORCPT ); Wed, 6 Apr 2005 09:27:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262208AbVDFN1U (ORCPT ); Wed, 6 Apr 2005 09:27:20 -0400 Received: from cam-admin0.cambridge.arm.com ([193.131.176.58]:29577 "EHLO cam-admin0.cambridge.arm.com") by vger.kernel.org with ESMTP id S262206AbVDFN0K (ORCPT ); Wed, 6 Apr 2005 09:26:10 -0400 To: Bas Vermeulen Cc: linux-kernel@vger.kernel.org Subject: Re: NOMMU - How to reserve 1 MB in top of memory in a clean way References: <1112781027.2687.6.camel@laptop.blackstar.nl> From: Catalin Marinas Date: Wed, 06 Apr 2005 14:26:08 +0100 In-Reply-To: <1112781027.2687.6.camel@laptop.blackstar.nl> (Bas Vermeulen's message of "Wed, 06 Apr 2005 11:50:28 +0200") Message-ID: User-Agent: Gnus/5.1007 (Gnus v5.10.7) Emacs/21.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 824 Lines: 19 Bas Vermeulen wrote: > I am currently working on the bfinnommu linux port for the BlackFin 533. > I need to grab the top 1 MB of memory so I can give it out to drivers > that need non-cached memory for DMA operations. I did this long time ago (on a 2.4 kernel), trying to avoid a hardware problem. I re-ordered the zones so that ZONE_DMA came after ZONE_NORMAL. Since the DMA memory was quite small (less than 1MB), I also put a "break" before "case ZONE_DMA" in the build_zonelists_node() functions to avoid the allocation fallback. -- Catalin - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/