From mboxrd@z Thu Jan 1 00:00:00 1970 From: bugzilla-daemon@bugzilla.kernel.org Subject: [Bug 60523] Radeon DPM not working with 2 monitors attached to Radeon HD5770 (Juniper) Date: Thu, 15 Aug 2013 21:40:28 +0000 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by gabe.freedesktop.org (Postfix) with ESMTP id D15F9E647A for ; Thu, 15 Aug 2013 14:40:30 -0700 (PDT) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 17E2A2037E for ; Thu, 15 Aug 2013 21:40:30 +0000 (UTC) Received: from bugzilla1.web.kernel.org (bugzilla1.web.kernel.org [172.20.200.51]) by mail.kernel.org (Postfix) with ESMTP id 7EFF7202F9 for ; Thu, 15 Aug 2013 21:40:28 +0000 (UTC) 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: dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org https://bugzilla.kernel.org/show_bug.cgi?id=60523 --- Comment #26 from Alex Deucher --- In order to switch the mclk, the hw needs at least 450us. The vblank period of the 1600x1200 mode is 396us, so it's not long enough to switch. The switch has to happen during vblank to avoid seeing a flicker when the mclk changes. As such the driver picks a power state where the mclk doesn't change (the same power state that is used for multi-head). You could try specifying a 1600x1200 modeline with a longer vblank period if you want to use that mode and still support mclk switching. -- You are receiving this mail because: You are watching the assignee of the bug.