From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH v3] OMAP: DMA: Fix omapfb/lcdc on OMAP1510 broken when PM set Date: Mon, 9 Nov 2009 13:14:24 -0800 Message-ID: <20091109211424.GF23952@atomide.com> References: <200911051951.32020.jkrzyszt@tis.icnet.pl> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <200911051951.32020.jkrzyszt@tis.icnet.pl> Sender: linux-omap-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Janusz Krzysztofik Cc: linux-omap@vger.kernel.org, linux-fbdev-devel@lists.sourceforge.net, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org * Janusz Krzysztofik [091105 10:52]: > With CONFIG_PM=y, the omapfb/lcdc device on Amstrad Delta, after initially > starting correctly, breaks with the following error messages: > > omapfb omapfb: resetting (status 0xffffff96,reset count 1) > ... > omapfb omapfb: resetting (status 0xffffff96,reset count 100) > omapfb omapfb: too many reset attempts, giving up. > > Looking closer at this I have found that it had been broken almost 2 years ago > with commit 2418996e3b100114edb2ae110d5d4acb928909d2, PM fixes for OMAP1. > > The definite reason for broken omapfb/lcdc behavoiur in PM mode > appeared to be ARM_IDLECT1:IDLIF_ARM (bit 6) put into idle regardless of LCD > DMA possibly running. The bit were set based on return value of the > omap_dma_running() function that did not check for dedicated LCD DMA > channel status. The patch below fixes this. > > Created against linux-2.6.32-rc6 > > Tested on Amstrad Delta > > Signed-off-by: Janusz Krzysztofik > > --- > Tuesday 03 November 2009 21:10:48 Tony Lindgren wrote: > > * Janusz Krzysztofik [091103 12:05]: > > > Sorry, I've not checked for new mail before posting this one and missed > > > your acceptance for my idea of fixing all omap1510, not only ams_delta. > > > If there are no more comments, I'll submit v3 with cpu_is_omap1510() > > > replacing machine_is_ams_delta(). > > > > Sounds good to me. > > > > Tony > > --- linux-2.6.32-rc6/arch/arm/plat-omap/dma.c.orig 2009-11-03 20:37:49.000000000 +0100 > +++ linux-2.6.32-rc6/arch/arm/plat-omap/dma.c 2009-11-05 19:30:39.000000000 +0100 > @@ -1108,6 +1108,14 @@ int omap_dma_running(void) > { > int lch; > > + /* > + * On OMAP1510, internal LCD controller will start the transfer > + * when it gets enabled, so assume DMA running if LCD enabled. > + */ > + if (cpu_is_omap1510()) > + if (omap_readw(0xfffec000 + 0x00) & (1 << 0)) > + return 1; > + > /* Check if LCD DMA is running */ > if (cpu_is_omap16xx()) > if (omap_readw(OMAP1610_DMA_LCD_CCR) & OMAP_DMA_CCR_EN) Can you please use some define rather than the 0xfffec000 register above? Regards, Tony