From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp3-g21.free.fr ([212.27.42.3]) by canuck.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1RIPnk-0005Id-S0 for barebox@lists.infradead.org; Mon, 24 Oct 2011 19:03:13 +0000 Received: from [192.168.2.8] (unknown [82.233.81.124]) by smtp3-g21.free.fr (Postfix) with ESMTP id 427B2A6324 for ; Mon, 24 Oct 2011 21:02:59 +0200 (CEST) Message-ID: <4EA5B65D.4020405@eukrea.com> Date: Mon, 24 Oct 2011 21:02:53 +0200 From: =?ISO-8859-1?Q?Eric_B=E9nard?= MIME-Version: 1.0 References: <1319289593-15251-1-git-send-email-fvanderwerf@gmail.com> <20111022202035.GK23421@pengutronix.de> <20111024170753.GN23421@pengutronix.de> In-Reply-To: List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1"; Format="flowed" Sender: barebox-bounces@lists.infradead.org Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH] usb: fix unaligned access To: barebox@lists.infradead.org Hi, Le 24/10/2011 20:37, Fabian van der Werf a =E9crit : > > Okay, I think it may be a compiler problem. The latest code sourcery > compiler builds a barebox that breaks on usb. 2009q1-203 builds fine, > however. > > In the usb code the compiler should be able to figure out that the > access is unaligned from the packed structure. So I guess it should > split up the access in multiple loads/stores. I will look into the > binaries to confirm this. The latest compiler may be broken or maybe > the default behaviour has changed because armv7 actually supports > unaligned access. > can't this be the same problem described here with gcc 4.6 : https://bugs.launchpad.net/ubuntu/+source/linux/+bug/791552 solved by this patch : https://launchpadlibrarian.net/73908303/0001-USB-ehci-remove-structure-pack= ing-from-ehci_def.patch with the following explanation : The kernel source marks ehci_regs as packed. gcc 4.6 treats all accesses to = packed structures as unaligned and ends up reading the status register = multiple times. Eric _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox