From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Nikula Subject: Re: [PATCH v3 1/2] omap: dma: Fix buffering disable bit setting for omap24xx Date: Mon, 4 Oct 2010 08:43:17 +0300 Message-ID: <20101004084317.725009ef.jhnikula@gmail.com> References: <1285936577-14881-1-git-send-email-peter.ujfalusi@nokia.com> <1285936577-14881-2-git-send-email-peter.ujfalusi@nokia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ey0-f174.google.com ([209.85.215.174]:45903 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136Ab0JDFm4 (ORCPT ); Mon, 4 Oct 2010 01:42:56 -0400 Received: by eyb6 with SMTP id 6so1700389eyb.19 for ; Sun, 03 Oct 2010 22:42:55 -0700 (PDT) In-Reply-To: Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "G, Manjunath Kondaiah" Cc: Peter Ujfalusi , Tony Lindgren , "linux-omap@vger.kernel.org" , Liam Girdwood On Sat, 2 Oct 2010 10:12:50 +0530 "G, Manjunath Kondaiah" wrote: > > --- a/arch/arm/plat-omap/dma.c > > +++ b/arch/arm/plat-omap/dma.c > > @@ -1000,7 +1000,7 @@ void omap_start_dma(int lch) > > * This will always fail on ES1.0 > > */ > > if (cpu_is_omap24xx()) > > - l |= OMAP_DMA_CCR_EN; > > + l |= OMAP_DMA_CCR_BUFFERING_DISABLE; > > This issue is applicable only for 2430ES1.0(not sure about 2420) > and it got fixed with later ES versions. > cpu check should be replaced with: > > if (cpu_is_omap2420() || (cpu_is_omap2430() && (omap_type() == OMAP2430_REV_ES1_0))) > Ok, thanks for your info, I'll change this. How about later versions of 2430? Should they use the workaround in Patch 2/2? We experimented that also on 2420 and it seemed to help but since the lockup was unrecovable I went thinking if 2420 has also another issue what original workaround was trying to fix and buffering disable was needed there. -- Jarkko