From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH 3/6] drm/i915: Wrap the preallocated BIOS framebuffer and preserve for KMS fbcon v7 Date: Sat, 14 Dec 2013 12:36:30 +0100 Message-ID: <20131214113630.GN9804@phenom.ffwll.local> References: <1386880917-2951-1-git-send-email-jbarnes@virtuousgeek.org> <1386880917-2951-3-git-send-email-jbarnes@virtuousgeek.org> <20131214111345.GK9804@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-ea0-f182.google.com (mail-ea0-f182.google.com [209.85.215.182]) by gabe.freedesktop.org (Postfix) with ESMTP id 913F2FADAE for ; Sat, 14 Dec 2013 03:35:38 -0800 (PST) Received: by mail-ea0-f182.google.com with SMTP id a15so1313972eae.41 for ; Sat, 14 Dec 2013 03:35:37 -0800 (PST) Content-Disposition: inline In-Reply-To: <20131214111345.GK9804@phenom.ffwll.local> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces@lists.freedesktop.org Errors-To: intel-gfx-bounces@lists.freedesktop.org To: Jesse Barnes Cc: intel-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Sat, Dec 14, 2013 at 12:13:45PM +0100, Daniel Vetter wrote: > On Thu, Dec 12, 2013 at 12:41:54PM -0800, Jesse Barnes wrote: > > + ifbdev->helper.funcs->initial_config = intel_fb_initial_config; > > This here is a bit surprising - my model of operation here presumed that > if we correctly assign the crtc->fb and the ifbdev->fb pointers we could > fully rely on the fastboot setcrtc logic to eschew the modeset. > > Being the ever-vary of special-purpose logic I'd much prefer this implicit > approach - otherwise we have one more special case to care about in the > fastboot=y/n and CONFIG_FB=y/n matrix. > > So have you tried to ditch this special initial_config functions > (obviously only looks good with fastboot=1) or what precise corner-case > does this fix? Ok, I've dug out your old patch from almost a year ago which added the ->initial_config hook. I see the point now of copying exactly the bios config in the hope that we end up with something that has a higher chance of working. But imo this is an issue separate from the "take over bios fb" feature here, so this should be - split into a separate patch - used even when we fail to take over the bios fb The later point will require some mode-from-pipe_config reconstruction to work outside of the fastboot=1 hack mode. I really like the idea though. -Daniel -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch