From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751502AbdIIXki (ORCPT ); Sat, 9 Sep 2017 19:40:38 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43076 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752684AbdIIXA3 (ORCPT ); Sat, 9 Sep 2017 19:00:29 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Christian =?UTF-8?Q?K=C3=B6nig?=" , "Alex Deucher" Date: Sat, 09 Sep 2017 22:47:14 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 091/233] drm/radeon/ci: disable mclk switching for high refresh rates (v2) In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.48-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Alex Deucher commit 58d7e3e427db1bd68f33025519a9468140280a75 upstream. Even if the vblank period would allow it, it still seems to be problematic on some cards. v2: fix logic inversion (Nils) bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868 Acked-by: Christian König Signed-off-by: Alex Deucher Signed-off-by: Ben Hutchings --- drivers/gpu/drm/radeon/ci_dpm.c | 6 ++++++ 1 file changed, 6 insertions(+) --- a/drivers/gpu/drm/radeon/ci_dpm.c +++ b/drivers/gpu/drm/radeon/ci_dpm.c @@ -733,6 +733,12 @@ bool ci_dpm_vblank_too_short(struct rade u32 vblank_time = r600_dpm_get_vblank_time(rdev); u32 switch_limit = pi->mem_gddr5 ? 450 : 300; + /* disable mclk switching if the refresh is >120Hz, even if the + * blanking period would allow it + */ + if (r600_dpm_get_vrefresh(rdev) > 120) + return true; + if (vblank_time < switch_limit) return true; else