From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jani Nikula Subject: Re: [Intel-gfx] Bad flicker on skylake HQD due to code in the 4.7 merge window Date: Tue, 13 Sep 2016 16:59:58 +0300 Message-ID: <87bmzr2941.fsf@intel.com> References: <1466112547.2311.3.camel@HansenPartnership.com> <1466116932.2257.4.camel@HansenPartnership.com> <20160617072826.GI23520@phenom.ffwll.local> <87vb18uef2.fsf@intel.com> <1466204815.2199.2.camel@HansenPartnership.com> <1466373202.2280.3.camel@HansenPartnership.com> <8737o89ti7.fsf@intel.com> <1466517195.2291.2.camel@HansenPartnership.com> <20160621154434.GY4329@intel.com> <20160707161425.GO4329@intel.com> <1467910504.2322.9.camel@HansenPartnership.com> <1467919176.2322.38.camel@HansenPartnership.com> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: James Hogan , James Bottomley Cc: intel-gfx , "Syrjala, Ville" , linux-kernel , dri-devel , Rodrigo Vivi List-Id: dri-devel@lists.freedesktop.org T24gU3VuLCAxMSBTZXAgMjAxNiwgSmFtZXMgSG9nYW4gPGphbWVzQGFsYmFuYXJ0cy5jb20+IHdy b3RlOgo+IEkndmUganVzdCBiaXNlY3RlZCBhIHNpbWlsYXIgKHNhbWU/KSBwcm9ibGVtIChzbG93 IGluY3JlYXNlIGFuZAo+IGRlY3JlYXNlIG9mIHNjcmVlbiBicmlnaHRuZXNzIHdpdGggYSBwZXJp b2Qgb2YgYSBmZXcgc2Vjb25kcykgdG8gdGhlCj4gc2FtZSBjb21taXQgKHRoaXMgaXMgb24gYSBE ZWxsIFhQUyAxMyBsYXB0b3ApCj4KPiBjb21taXQgYTA1NjI4MTk1YTBkOWYzMTczZGQ5YWE3NmY0 ODJhZWY2OTJlNDZlZQo+IEF1dGhvcjogVmlsbGUgU3lyasOkbMOkIDx2aWxsZS5zeXJqYWxhQGxp bnV4LmludGVsLmNvbT4KPiBEYXRlOiAgIE1vbiBBcHIgMTEgMTA6MjM6NTEgMjAxNiArMDMwMAo+ Cj4gICAgIGRybS9pOTE1OiBHZXQgcGFuZWxfdHlwZSBmcm9tIE9wUmVnaW9uIHBhbmVsIGRldGFp bHMKPgo+IHRoZSBkaWZmZXJlbmNlIGZvciBtZSBpcyB0aGF0IGdvb2QgY29tbWl0cyB1c2VkIHRo ZSBhY3BpIGJhY2tsaWdodCwKPiBhbmQgYmFkIG9uZXMgdXNlZCB0aGUgaW50ZWwgYmFja2xpZ2h0 ICgvc3lzL2NsYXNzL2JhY2tsaWdodC8pLiBJdHMKPiBsaWtlIGludGVsX2JhY2tsaWdodCBpcyBm aWdodGluZyB3aXRoIHRoZSBmaXJtd2FyZSB0byBjb250cm9sIHRoZQo+IGJhY2tsaWdodCBvciBz b21ldGhpbmcuIFJldmVydGluZyB0aGUgY29tbWl0IG9uIHY0LjcuMyBzd2l0Y2hlcyBpdAo+IGJh Y2sgdG8gdGhlIGFjcGkgYmFja2xpZ2h0IGFuZCBhbGwgd29ya3MgbmljZWx5IGFnYWluLgo+Cj4g bGV0IG1lIGtub3cgaWYgSSBjYW4gcHJvdmlkZSBhbnl0aGluZyBlbHNlIHRvIGhlbHAgZGVidWcu CgpQbGVhc2UgdHJ5IFsxXS4KCkJSLApKYW5pLgoKWzFdIGh0dHA6Ly9wYXRjaHdvcmsuZnJlZWRl c2t0b3Aub3JnL3BhdGNoL21zZ2lkLzE0NzM3NTg1MzktMjE1NjUtMS1naXQtc2VuZC1lbWFpbC12 aWxsZS5zeXJqYWxhQGxpbnV4LmludGVsLmNvbQoKCi0tIApKYW5pIE5pa3VsYSwgSW50ZWwgT3Bl biBTb3VyY2UgVGVjaG5vbG9neSBDZW50ZXIKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fX19fX18KZHJpLWRldmVsIG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMu ZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlzdHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlz dGluZm8vZHJpLWRldmVsCg== From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757474AbcIMOAF convert rfc822-to-8bit (ORCPT ); Tue, 13 Sep 2016 10:00:05 -0400 Received: from mga09.intel.com ([134.134.136.24]:46838 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751433AbcIMOAD (ORCPT ); Tue, 13 Sep 2016 10:00:03 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.30,328,1470726000"; d="scan'208";a="167659823" From: Jani Nikula To: James Hogan , James Bottomley Cc: "Syrjala\, Ville" , intel-gfx , linux-kernel , dri-devel , Rodrigo Vivi Subject: Re: [Intel-gfx] Bad flicker on skylake HQD due to code in the 4.7 merge window In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <1466112547.2311.3.camel@HansenPartnership.com> <1466116932.2257.4.camel@HansenPartnership.com> <20160617072826.GI23520@phenom.ffwll.local> <87vb18uef2.fsf@intel.com> <1466204815.2199.2.camel@HansenPartnership.com> <1466373202.2280.3.camel@HansenPartnership.com> <8737o89ti7.fsf@intel.com> <1466517195.2291.2.camel@HansenPartnership.com> <20160621154434.GY4329@intel.com> <20160707161425.GO4329@intel.com> <1467910504.2322.9.camel@HansenPartnership.com> <1467919176.2322.38.camel@HansenPartnership.com> User-Agent: Notmuch/0.22.1+62~g2a7b11b (https://notmuchmail.org) Emacs/24.4.1 (x86_64-pc-linux-gnu) Date: Tue, 13 Sep 2016 16:59:58 +0300 Message-ID: <87bmzr2941.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 11 Sep 2016, James Hogan wrote: > I've just bisected a similar (same?) problem (slow increase and > decrease of screen brightness with a period of a few seconds) to the > same commit (this is on a Dell XPS 13 laptop) > > commit a05628195a0d9f3173dd9aa76f482aef692e46ee > Author: Ville Syrjälä > Date: Mon Apr 11 10:23:51 2016 +0300 > > drm/i915: Get panel_type from OpRegion panel details > > the difference for me is that good commits used the acpi backlight, > and bad ones used the intel backlight (/sys/class/backlight/). Its > like intel_backlight is fighting with the firmware to control the > backlight or something. Reverting the commit on v4.7.3 switches it > back to the acpi backlight and all works nicely again. > > let me know if I can provide anything else to help debug. Please try [1]. BR, Jani. [1] http://patchwork.freedesktop.org/patch/msgid/1473758539-21565-1-git-send-email-ville.syrjala@linux.intel.com -- Jani Nikula, Intel Open Source Technology Center