From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by yocto-www.yoctoproject.org (Postfix, from userid 118) id D190FE00997; Thu, 1 May 2014 03:00:01 -0700 (PDT) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on yocto-www.yoctoproject.org X-Spam-Level: X-Spam-Status: No, score=-0.0 required=5.0 tests=SPF_HELO_PASS autolearn=ham version=3.3.1 X-Spam-HAM-Report: * -0.0 SPF_HELO_PASS SPF: HELO matches SPF record X-Greylist: delayed 549 seconds by postgrey-1.32 at yocto-www; Thu, 01 May 2014 02:59:55 PDT Received: from ptmx.org (ptmx.org [178.63.28.110]) by yocto-www.yoctoproject.org (Postfix) with ESMTP id 6F7A8E00985 for ; Thu, 1 May 2014 02:59:55 -0700 (PDT) Received: from [192.168.178.14] (chello080108088242.14.11.vie.surfer.at [80.108.88.242]) by ptmx.org (Postfix) with ESMTPSA id 483B329FD2; Thu, 1 May 2014 11:50:45 +0200 (CEST) Message-ID: <536218F4.2090708@pseudoterminal.org> Date: Thu, 01 May 2014 11:50:44 +0200 From: Carlos Rafael Giani User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.4.0 MIME-Version: 1.0 To: Eric Nelson , "meta-freescale@yoctoproject.org" References: <5328BD2A.2080800@pseudoterminal.org> <5328E44D.4040201@boundarydevices.com> In-Reply-To: <5328E44D.4040201@boundarydevices.com> Subject: Re: Missing vsync support in Vivante drivers X-BeenThere: meta-freescale@yoctoproject.org X-Mailman-Version: 2.1.13 Precedence: list List-Id: Usage and development list for the meta-fsl-* layers List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 01 May 2014 10:00:01 -0000 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 2014-03-19 01:26, Eric Nelson wrote: > Hi Carlos, > > On 03/18/2014 02:39 PM, Carlos Rafael Giani wrote: >> Hello, >> >> in the past, there has always been a problem with vsync, OpenGL ES >> output, and X11. Very noticeable tearing affects all such applications. >> So far, neither Vivante nor Freescale have ever commented on this. Is >> there anything known? Should the newest drivers fix this? > > You have odd timing. I was just looking into this today for a > customer. > > In our kernels and the Freescale kernels. there seems to be an > issue with the default allocation of the frame-buffer, such that > only space for a single buffer is present. > > http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/video/mxc/mxc_ipuv3_fb.c?h=imx_3.0.35_4.1.0#n862 > > > Without a larger allocation, I don't think the frame buffer > driver has any way of swapping cleanly at vertical sync. > > The 3.10.17-beta kernel seems to do the same thing: > http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git/tree/drivers/video/mxc/mxc_ipuv3_fb.c?h=imx_3.10.17_1.0.0_beta#n870 > > > You can see this at run-time by looking in > /sys/class/graphics/fb0/virtual_size. > > # cat /sys/class/graphics/fb0/mode > U:1280x800p-59 > # cat /sys/class/graphics/fb0/virtual_size > 1280,800 > > You can also alter things by using sysfs: > # echo 1280,1600 > /sys/class/graphics/fb0/virtual_size > > After changing the size, the FBIO_PAN ioctl does the right > thing. i.e.: > > variable_info.yoffset = x; > err = ioctl(fdfb,FBIOPAN_DISPLAY,&variable_info); > > And you can see the same thing using /sys/class/graphics/fb0/pan. > > It's not clear to me who should be doing this though. > > In an X environment, I would expect this to be controlled > through xorg.conf somehow, but my attempts to get fbdev > and shadowfb proved fruitless. > > I haven't had a chance to look into the Vivante X driver > and I'm not sure where the OpenGL stack this should be > performed, but since the timing really has to be coordinated > by the frame-buffer, there should be a call somewhere. > > In my immediate customer case, using the frame buffer calls > directly is sufficient. > > Regards, > > > Eric Hello Eric, are there any updates on this? With the Weston imx patches, tearing-free X11 is less urgent, but still very welcome, and some installations just absolutely need X11. Carlos