From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH 1/5] drm/i915: Initialise g4x watermarks for disabled pipes Date: Tue, 05 Apr 2011 22:12:19 +0100 Message-ID: References: <1301995458-2699-1-git-send-email-chris@chris-wilson.co.uk> <1301995458-2699-2-git-send-email-chris@chris-wilson.co.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id 10D309E734 for ; Tue, 5 Apr 2011 14:12:23 -0700 (PDT) In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Keith Packard , intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 05 Apr 2011 13:56:37 -0700, Keith Packard wrote: > On Tue, 5 Apr 2011 10:24:14 +0100, Chris Wilson wrote: > > > crtc = intel_get_crtc_for_plane(dev, plane); > > - if (crtc->fb == NULL || !crtc->enabled) > > + if (crtc->fb == NULL || !crtc->enabled) { > > + *cursor_wm = *plane_wm = display->guard_size; > > return false; > > + } > > Would it be clearer to have g4x_update_wm set these instead? > > I'm also a bit concerned about the default value; it would be lovely to > have the docs say what the value should be for disabled pipes, but I > couldn't find any mention of them. Indeed, I started by setting them to zero in the caller. Decided that there was some precedent to use the guard_size as the minimum value for unused planes (and so perhaps the unused planes on the unused pipes) and so it was then natural to do it inside g4x_compute_wm. I guess it all depends on how many FIFOs are split between the pipes. Using guard_size, I believe, should be safest. -Chris -- Chris Wilson, Intel Open Source Technology Centre