Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754480Ab2JBW27 (ORCPT ); Tue, 2 Oct 2012 18:28:59 -0400 Received: from mail-vb0-f46.google.com ([209.85.212.46]:49903 "EHLO mail-vb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752642Ab2JBW25 (ORCPT ); Tue, 2 Oct 2012 18:28:57 -0400 MIME-Version: 1.0 In-Reply-To: <506B69B0.2010109@am.sony.com> References: <506B69B0.2010109@am.sony.com> Date: Tue, 2 Oct 2012 17:28:54 -0500 Message-ID: Subject: Re: Problem with mmc DMA on panda board in 3.6 From: Robert Nelson To: Tim Bird Cc: "linux-arm-kernel@lists.infradead.org" , linux kernel Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1914 Lines: 52 On Tue, Oct 2, 2012 at 5:24 PM, Tim Bird wrote: > This is an early report - I'm just checking if anyone else has seen this. > > With Linux version v3.6, my PandaBoard (OMAP-based) no longer boots. The > system appears to fail to initialize the mmc controller. > > The kernel log message of interest appears to be this: > [ 1.690002] omap_hsmmc omap_hsmmc.0: unable to obtain RX DMA engine channel 6 > > I can supply full kernel log messages and my .config if needed. > > I bisected the code and arrived at the following commit: > ------- > commit 26b88520b80695a6fa5fd95b5d97c03f4daf87e0 > Author: Russell King > Date: Fri Apr 13 12:27:37 2012 +0100 > > mmc: omap_hsmmc: remove private DMA API implementation > > Remove the private DMA API implementation from omap_hsmmc, making it > use entirely the DMA engine API. > > Tested-by: Tony Lindgren > Tested-by: Venkatraman S > Signed-off-by: Russell King > ------- > The board works up until this commit. > After this commit, the board hangs during boot after the message: > [ 1.852508] Waiting for root device /dev/mmcblk0p3... > (and some other USB and network messages, which I presume > are unrelated.) > > My questions are these: > Has anyone else had problems with the PandaBoard (or other OMAP) on 3.6? > Are there any related CONFIG_ variables I could change to try alternatives? > What should I try next to debug this? Check your config, to see if these are enabled: CONFIG_DMADEVICES=y CONFIG_DMA_OMAP=y Regards, -- Robert Nelson http://www.rcn-ee.com/ -- 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/