From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrzej Hajda Subject: Re: [drm/exynos-fimd] Display regression in v3.12-rc1 Date: Wed, 18 Sep 2013 08:48:23 +0200 Message-ID: <52394CB7.7080509@samsung.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mailout2.w1.samsung.com (mailout2.w1.samsung.com [210.118.77.12]) by gabe.freedesktop.org (Postfix) with ESMTP id 08D0EE5BF4 for ; Tue, 17 Sep 2013 23:48:46 -0700 (PDT) Received: from eucpsbgm1.samsung.com (unknown [203.254.199.244]) by mailout2.w1.samsung.com (Oracle Communications Messaging Server 7u4-24.01(7.0.4.24.0) 64bit (built Nov 17 2011)) with ESMTP id <0MTB00IS86VZMD70@mailout2.w1.samsung.com> for dri-devel@lists.freedesktop.org; Wed, 18 Sep 2013 07:48:43 +0100 (BST) In-reply-to: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org Errors-To: dri-devel-bounces+sf-dri-devel=m.gmane.org@lists.freedesktop.org To: Sachin Kamat Cc: Vikas Sajjan , "dri-devel@lists.freedesktop.org" List-Id: dri-devel@lists.freedesktop.org Hi Sachin, Could you test it with removed display-timings::clock-frequency property. Currently in arch/arm/boot/dts/exynos4210-origen.dts display-timings::clock-frequency is set to 50000, this is incorrect value. With the property removed fimd calculates clock-frequency from other properties with assumption of default 60Hz refresh rate. It could work before because of_get_fb_videomode calculated refresh rate from display-timings and with clock 50000, the result was 0(due to rounding down in some division), so fimd assumed he should use default refresh rate of 60Hz. Regards Andrzej On 09/18/2013 07:22 AM, Sachin Kamat wrote: > Hi Andrzej , > > I was testing the latest Linux kernel release (v3.12-rc1) on > Exynos4210 based Origen board. > I found a display regression with that. I do not get any display on > the LCD (other than backlight) with the latest kernel. Git bisect > pointed me to the following commit: > 111e6055d4e0d35c6a4b6cd37d7bb00a88eaffb4 ("drm/exynos: fimd: replace > struct fb_videomode with videomode"). Reverting this patch does not > cause the issue. Let me know if you need any other info to help > identify the problem. >