From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugs.freedesktop.org Subject: [Bug 87682] Horizontal lines in radeon driver on kernel 3.15 and upwards Date: Tue, 10 May 2016 22:12:05 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1125041550==" Return-path: Received: from culpepper.freedesktop.org (culpepper.freedesktop.org [IPv6:2610:10:20:722:a800:ff:fe98:4b55]) by gabe.freedesktop.org (Postfix) with ESMTP id 32C456E228 for ; Tue, 10 May 2016 22:12:05 +0000 (UTC) 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: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org --===============1125041550== Content-Type: multipart/alternative; boundary="14629183252.09D4ABf.7851"; charset="UTF-8" --14629183252.09D4ABf.7851 Date: Tue, 10 May 2016 22:12:05 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.freedesktop.org/ Auto-Submitted: auto-generated https://bugs.freedesktop.org/show_bug.cgi?id=3D87682 --- Comment #17 from Chris Bainbridge --- Christian K=C3=B6nig posted an explanation of the PLL divider values at https://bugzilla.kernel.org/show_bug.cgi?id=3D91861#c12 (another "no screen= after 3.15" bug report) The various fixes adjust the divider value limits slightly for different displays. The basic formula is commented in the radeon_compute_pll_avivo function: dot_clock =3D (ref_freq * feedback_div) / (ref_div * post_div) So by adjusting the limits of those values you can find something that works for your laptop display. But I don't know which solution is technically cor= rect - if you don't get a reply here you could try emailing Christian K=C3=B6nig= and asking. --=20 You are receiving this mail because: You are the assignee for the bug.= --14629183252.09D4ABf.7851 Date: Tue, 10 May 2016 22:12:05 +0000 MIME-Version: 1.0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://bugs.freedesktop.org/ Auto-Submitted: auto-generated

Commen= t # 17 on bug 87682<= /a> from Chris Bainbridge 
Christian K=C3=B6nig posted an explanation of the PLL divider =
values at
https:/=
/bugzilla.kernel.org/show_bug.cgi?id=3D91861#c12 (another "no scre=
en after
3.15" bug report)

The various fixes adjust the divider value limits slightly for different
displays. The basic formula is commented in the radeon_compute_pll_avivo
function:

        dot_clock =3D (ref_freq * feedback_div) / (ref_div * post_div)

So by adjusting the limits of those values you can find something that works
for your laptop display. But I don't know which solution is technically cor=
rect
- if you don't get a reply here you could try emailing Christian K=C3=B6nig=
 and
asking.

You are receiving this mail because:
  • You are the assignee for the bug.
= --14629183252.09D4ABf.7851-- --===============1125041550== Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Content-Disposition: inline X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KZHJpLWRldmVs IG1haWxpbmcgbGlzdApkcmktZGV2ZWxAbGlzdHMuZnJlZWRlc2t0b3Aub3JnCmh0dHBzOi8vbGlz dHMuZnJlZWRlc2t0b3Aub3JnL21haWxtYW4vbGlzdGluZm8vZHJpLWRldmVsCg== --===============1125041550==--