Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751623AbbD3P51 (ORCPT ); Thu, 30 Apr 2015 11:57:27 -0400 Received: from mail-ob0-f179.google.com ([209.85.214.179]:36733 "EHLO mail-ob0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751013AbbD3P5X (ORCPT ); Thu, 30 Apr 2015 11:57:23 -0400 MIME-Version: 1.0 X-Originating-IP: [2620:0:1000:157d:59b5:7dd4:5c20:bbb] In-Reply-To: <7h8ud9pqmm.fsf@deeprootsystems.com> References: <1427471856-20918-1-git-send-email-k.kozlowski@samsung.com> <7h8udau9he.fsf@deeprootsystems.com> <7h8ud9pqmm.fsf@deeprootsystems.com> Date: Thu, 30 Apr 2015 08:57:22 -0700 Message-ID: Subject: Re: [RFT PATCH] drm/exynos: Enable DP clock to fix display on Exynos5250 and other From: Olof Johansson To: Kevin Hilman Cc: Krzysztof Kozlowski , "linux-fbdev@vger.kernel.org" , "linux-samsung-soc@vger.kernel.org" , Joonyoung Shim , David Airlie , Jingoo Han , Seung-Woo Kim , "linux-kernel@vger.kernel.org" , DRI mailing list , Inki Dae , Andrzej Hajda , Kyungmin Park , Kukjin Kim , stable , Javier Martinez Canillas , "linux-arm-kernel@lists.infradead.org" , Marek Szyprowski Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2662 Lines: 68 On Thu, Apr 30, 2015 at 8:44 AM, Kevin Hilman wrote: > Krzysztof Kozlowski writes: > >> 2015-04-30 2:31 GMT+09:00 Kevin Hilman : >>> Krzysztof Kozlowski writes: >>> >>>> After adding display power domain for Exynos5250 in commit >>>> 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250") the >>>> display on Chromebook Snow and others stopped working after boot. >>>> >>>> The reason for this suggested Andrzej Hajda: the DP clock was disabled. >>>> This clock is required by Display Port and is enabled by bootloader. >>>> However when FIMD driver probing was deferred, the display power domain >>>> was turned off. This effectively reset the value of DP clock enable >>>> register. >>>> >>>> When exynos-dp is later probed, the clock is not enabled and display is >>>> not properly configured: >>>> >>>> exynos-dp 145b0000.dp-controller: Timeout of video streamclk ok >>>> exynos-dp 145b0000.dp-controller: unable to config video >>>> >>>> Signed-off-by: Krzysztof Kozlowski >>>> Reported-by: Javier Martinez Canillas >>>> Fixes: 2d2c9a8d0a4f ("ARM: dts: add display power domain for exynos5250") >>>> Cc: >>>> >>>> --- >>>> >>>> This should fix issue reported by Javier [1][2]. >>>> >>>> Tested on Chromebook Snow (Exynos 5250). More testing would be great, >>>> especially on other Exynos 5xxx products. >>> >>> I hoped to try this on my exynos5 boards, but it doesn't seem to apply >>> to linux-next or to Linus' master branch. >>> >>> Are there some other dependencies here? >> >> It is already applied: >> https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=1c363c7cccf64128087002b0779986ad16aff6dc > > Er, yup. That would explain it. ;) > > Sorry for the noise, Well, noise or not, Exynos is still broken in mainline and was broken on -next for so long in different ways that bisecting it is a futile exercise in frustration. It doesn't seem to show up with a trivial boot using only ramdisk, but when booting a real distro from disk, it certainly does. For example: http://arm-soc.lixom.net/bootlogs/mainline/v4.1-rc1-56-g3d99e3f/pi-arm-exynos_defconfig.html Disabling CONFIG_DRM makes it boot reliably. Arndale doesn't show it for me, but it also doesn't have working graphics. -Olof -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/