From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751494Ab3ASOsd (ORCPT ); Sat, 19 Jan 2013 09:48:33 -0500 Received: from smtp1-g21.free.fr ([212.27.42.1]:45178 "EHLO smtp1-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751265Ab3ASOsc (ORCPT ); Sat, 19 Jan 2013 09:48:32 -0500 Message-ID: <50FAB219.5020108@free.fr> Date: Sat, 19 Jan 2013 15:47:53 +0100 From: dAgeCKo User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.11) Gecko/20121122 Icedove/10.0.11 MIME-Version: 1.0 To: Borislav Petkov , "H. Peter Anvin" , linux-kernel@vger.kernel.org, Alan Stern , linux-usb@vger.kernel.org, Shane Huang , =?UTF-8?B?SsO2cmcgUsO2ZGVs?= Subject: Re: Fwd: Linux - AMD SB950 USB Regression References: <50C9FCD6.6050809@free.fr> <50E6AD77.1000707@free.fr> <50F036CF.7010109@free.fr> <20130117213602.GA5998@pd.tnic> In-Reply-To: <20130117213602.GA5998@pd.tnic> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le 17/01/2013 22:36, Borislav Petkov a écrit : > > So, there seems to be some serious breakage with GART on SB9xx. I don't > know whether this is the platform BIOS or the vendor BIOS causing it > because the original bug reporter says he observes the issue on an MSI > board and I'm experiencing this on my favourite bunch ASUS. > > So, if you use the GART as an IOMMU, i.e.: > > Jan 17 22:08:15 pd kernel: [ 0.924063] PCI-DMA: using GART IOMMU. > Jan 17 22:08:15 pd kernel: [ 0.924120] PCI-DMA: Reserving 64MB of IOMMU area in the AGP aperture > > USB ports start choking like this: > > Jan 17 22:08:15 pd kernel: [ 3.229909] usb 4-1: device descriptor read/64, error -32 > Jan 17 22:08:15 pd kernel: [ 3.432786] usb 4-1: new high-speed USB device number 3 using ehci-pci > Jan 17 22:08:15 pd kernel: [ 3.534684] usb 4-1: device descriptor read/64, error -32 > Jan 17 22:08:15 pd kernel: [ 3.737642] usb 4-1: device descriptor read/64, error -32 Yes, this is exactly what I faced. > > I'd go and venture a guess here since I don't have an idea that DMA > somehow gets busted with the GART and thus the errors. > > Now, those boards normally have an IOMMU too so if you go and enable > > CONFIG_AMD_IOMMU=y > > the problem is gone (we're using the real IOMMU for DMA mapping, etc, > etc). So dAgeCKo, that would be another thing you could do: try enabling > the IOMMU in the BIOS and the above CONFIG option and the issue would be > fixed too. Here is below, exactly what the guy from MSI said me after I said him a BIOS upgrade did resolve my bug: "The reacts differently to Win/Linux, but it relies on updates by AMD. The new AGESA in the BIOS might had fixes for Linux." After few researches, it seems that this "BIOS-level" software has effectively a special implementation wrapper for Linux (something I can't understand why actually). For more reference you can find little information here (http://www.coreboot.org/data/LinuxBIOS%20AMD%202006%20Final_10-02-2006.pdf). I can't try the solution you are giving since I can't (and don't want to try to) downgrade my BIOS. Another important thing you might be interested in is that not only my USB 2 weren't working. My mainboard ethernet wasn't working to (and was resolved with the BIOS upgrade too). The ethernet chip is: 03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 06) I don't know if that can be related to what you are saying. > > At least this fixes it on my box. > > To the question "how do we fix the GART issue?" I have no answer and > would expect more informed opinions from someone else. Actually I can't tell if I have any GART issues. The only thing I can say is that 3D looks to work nicely. However I think I never consumed more memory than my graphic card has. > > Thanks and HTH. > Thanks you too.