From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753137Ab0L2BAU (ORCPT ); Tue, 28 Dec 2010 20:00:20 -0500 Received: from mail-qw0-f46.google.com ([209.85.216.46]:57103 "EHLO mail-qw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751993Ab0L2BAR (ORCPT ); Tue, 28 Dec 2010 20:00:17 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=w/KPi52Xjq/KU1ueZethzbyYW0jJV2u0Q0YGlRburfzTEBLZpp4nMC2Ia82OMI5e2K 2fbQnCoB7Ulf/9HAloeZbhfyKCMELbUVxhQvAbMlvUkSZvgSeKQGRF9+bePxIeRTCuGh YwcpdSCSyRkLJvPY3zFUYnWNGlJiggE/ymx6w= Message-ID: <4D1A881C.3080109@garzik.org> Date: Tue, 28 Dec 2010 20:00:12 -0500 From: Jeff Garzik User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.13) Gecko/20101209 Fedora/3.1.7-0.35.b3pre.fc14 Thunderbird/3.1.7 MIME-Version: 1.0 To: Steffen Moser CC: linux-kernel@vger.kernel.org, Linux IDE mailing list , Joerg Roedel Subject: Re: IOMMU and DMA mode of pata_jmicron References: <4D1A7628.3050704@steffen-moser.de> In-Reply-To: <4D1A7628.3050704@steffen-moser.de> Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (CC'd linux-ide, Joerg) On 12/28/2010 06:43 PM, Steffen Moser wrote: > I've encountered a problem with my AMD 890FX based system > and linux-2.6.35.10 (x86_64 platform). > > After activating the option "IOMMU" in the mainboard's BIOS > setup, the onboard P-ATA controller "JMicron Technology Corp. > JMB361 AHCI/IDE (rev 02)" puts itself back in the PIO mode. > When loading the module, the kernel reports: > > pata_jmicron 0000:06:00.1: BMDMA: failed to set dma mask, \ > falling back to PIO [...] > As soon as I deactivate IOMMU in BIOS setup, the P-ATA channel > runs in the DMA mode again. The S-ATA controllers don't seem > to be affected. > > My question is: Is this a known behavior? Are there any > things I have to consider when activating IOMMU (which seems > to be AMD-Vi) on an 890FX based system? Is it a problem of > the chipset and/or the controller or is it related to a > problem in the libata area? > > Some information about the affected system: > > - Mainboard: ASUS M4A89TD Pro/USB3 > - BIOS version: 1101 (most recent version) > - Chipset: AMD 890FX > - Processor: AMD Phenom 1090T > - Memory: 4 x 4 GB (Kingston KVR1333D3E9S/4G) > - Distribution: openSUSE 11.3 > - Kernel: 2.6.35.10 (from "kernel.org"), x86_64 > This condition occurs when the PCI API cannot set the PCI device's DMA mask to the 32-bit value #define ATA_DMA_MASK 0xffffffffULL That is an unusual failure for such a modern system, which certainly can handle 32-bit masks like that, one would think. Jeff