From mboxrd@z Thu Jan 1 00:00:00 1970 From: eric.nelson@boundarydevices.com (Eric Nelson) Date: Sat, 22 Sep 2012 10:52:12 -0700 Subject: [PATCH 4/6] staging: drm/imx: Add i.MX IPUv3 crtc support In-Reply-To: <20120922101727.GG1322@pengutronix.de> References: <1348214872-28594-1-git-send-email-s.hauer@pengutronix.de> <1348214872-28594-5-git-send-email-s.hauer@pengutronix.de> <505C94B3.3020308@boundarydevices.com> <20120922101727.GG1322@pengutronix.de> Message-ID: <505DFACC.7010604@boundarydevices.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 09/22/2012 03:17 AM, Sascha Hauer wrote: > Hi Eric, > > On Fri, Sep 21, 2012 at 09:24:19AM -0700, Eric Nelson wrote: >> Hi Sascha, >> >> >> But ipu_crtc->imx_crtc gets initialized in this call, and >> ipu_irq_handler() makes use of it. >> >> The U-Boot code doesn't enable interrupts, so it's not acking >> along the way, and leaves bits set in IPU1_INT_STAT_15. >> >> I found that I can get around this in U-Boot by disabling the >> LCD controller and acking all of the interrupts after disabling >> the controller, but I haven't yet figured out where to tap into >> cleanup_before_linux(). > > Passing over an enabled IPU from the bootloader to the kernel is > (currently) not a supported usecase, so U-Boot should indeed disable it. > That said, the kernel driver should make sure the IPU is sufficiently > configured before the interrupts are enabled, so this seems to be a bug > that deserves fixing. > Thanks Sascha, Patches for U-Boot are in process. http://lists.denx.de/pipermail/u-boot/2012-September/134807.html Regards, Eric