From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754051AbaE1HMb (ORCPT ); Wed, 28 May 2014 03:12:31 -0400 Received: from mail.dev.rtsoft.ru ([213.79.90.226]:46732 "EHLO dev.rtsoft.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751397AbaE1HMa (ORCPT ); Wed, 28 May 2014 03:12:30 -0400 Message-ID: <53858C5B.6030604@dev.rtsoft.ru> Date: Wed, 28 May 2014 11:12:27 +0400 From: Nikita Yushchenko Organization: RTSoft Software Development Center User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:24.0) Gecko/20100101 Icedove/24.5.0 MIME-Version: 1.0 To: Greg Kroah-Hartman CC: Mathias Nyman , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, lugovskoy@dev.rtsoft.ru Subject: Re: [PATCH] usb: pci-quirks: do not access OHCI_FMINTERVAL register on ULI hw References: <1401166602-26379-1-git-send-email-nyushchenko@dev.rtsoft.ru> <20140527232715.GA26228@kroah.com> In-Reply-To: <20140527232715.GA26228@kroah.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 28.05.2014 03:27, Greg Kroah-Hartman пишет: > On Tue, May 27, 2014 at 08:56:42AM +0400, Nikita Yushchenko wrote: >> This access causes hang on Freescale P2020DS board (that has OHCI >> provided by ULI 1533 chip). >> >> Since preserving OHCI_FMINTERVAL was originally done only for NVIDIA >> hardware and only later (in c6187597) was turned unconditional, and >> c6187597 commit message again mentions only NVIDIA, I think it should be >> safe to disable preserving OHCI_FMINTERVAL if device vendor is ULI. > > Have you tested this? With this applied, board boots ok. With this not applied, board hangs on boot. As for OHCI functionality - this was tested by other people here, but with older kernel. Will retest myself with 3.15-rc as soon as get physical access to board. >> - u32 fminterval; >> + u32 uninitialized_var(fminterval); > > Why is this change needed? Sounds like a compiler bug to me :) CC drivers/usb/host/pci-quirks.o In file included from include/linux/io.h:22:0, from include/linux/pci.h:31, from drivers/usb/host/pci-quirks.c:14: drivers/usb/host/pci-quirks.c: In function 'quirk_usb_early_handoff': /home/cge7/nikita/kernel-u/arch/powerpc/include/asm/io.h:180:1: warning: 'fminterval' may be used uninitialized in this function [-Wmaybe-uninitialized] drivers/usb/host/pci-quirks.c:574:6: note: 'fminterval' was declared here gcc version 4.7.0 (MontaVista Linux G++ 4.7-140519214821) Nikita