Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 2 Mar 2001 10:31:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 2 Mar 2001 10:31:30 -0500 Received: from ns2.cypress.com ([157.95.67.5]:64158 "EHLO ns2.cypress.com") by vger.kernel.org with ESMTP id ; Fri, 2 Mar 2001 10:31:20 -0500 Message-ID: <3A9FBCB4.3F3931F8@cypress.com> Date: Fri, 02 Mar 2001 09:31:00 -0600 From: Thomas Dodd Organization: Cypress Semiconductor Southeast Design Center X-Mailer: Mozilla 4.76 [en] (X11; U; SunOS 5.8 sun4u) X-Accept-Language: en-US, en-GB, en, de-DE, de-AT, de-CH, de, zh-TW, zh-CN, zh MIME-Version: 1.0 To: linux-kernel@vger.kernel.org, Hylke van der Schaaf Subject: Re: DMA on a AMD7409 controller with kernel 2.4.2 In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > On Thu, 1 Mar 2001, Hylke van der Schaaf wrote: > > > With kernet 2.2.18 DMA mode for my harddisks worked just fine, > > getting IDE DMA working on an AMD7409 controller with kernel 2.4.2 is a problem. > > > > questions: > > Why is DMA disabled on revision < C4? > > How can I gat DMA working again? > > in 2.2.18 I get: > > hylke:/home/hylke# hdparm -tT /dev/hda > > > > /dev/hda: > > Timing buffer-cache reads: 128 MB in 0.89 seconds =143.82 MB/sec > > Timing buffered disk reads: 64 MB in 2.85 seconds = 22.46 MB/sec > > ---------------------------- > > > > All was fine. > > I compiled 2.4.2, with: > > CONFIG_AMD7409_OVERRIDE=y I'm not using this, since my drives are not UDMA66 or UDMA100 > > hylke:/home/hylke# hdparm -v /dev/hda > > > > /dev/hda: > > multcount = 16 (on) > > I/O support = 1 (32-bit) > > unmaskirq = 1 (on) > > using_dma = 0 (off) > > keepsettings = 0 (off) > > nowerr = 0 (off) > > readonly = 0 (off) > > readahead = 8 (on) > > geometry = 2495/255/63, sectors = 40088160, start = 0 > > hylke:/home/hylke# hdparm -tT /dev/hda > > > > /dev/hda: > > Timing buffer-cache reads: 128 MB in 0.90 seconds =142.22 MB/sec > > Timing buffered disk reads: 64 MB in 12.59 seconds = 5.08 MB/sec I get 148.8 and 12 MB/sec on my IBM-DTTA-351010 drives. I get the same message about no single word DMA due to chip revision. # hdparm -v /dev/hda /dev/hda: multcount = 16 (on) I/O support = 3 (32-bit w/sync) unmaskirq = 0 (off) using_dma = 1 (on) keepsettings = 0 (off) nowerr = 0 (off) readonly = 0 (off) readahead = 8 (on) geometry = 19650/16/63, sectors = 19807200, start = 0 What does /proc/ide/hda/settings show? What about /proc/ide/amd74xx ? -Thomas - 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/