From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932837AbcFCTCD (ORCPT ); Fri, 3 Jun 2016 15:02:03 -0400 Received: from mail-wm0-f65.google.com ([74.125.82.65]:33794 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752694AbcFCTB6 (ORCPT ); Fri, 3 Jun 2016 15:01:58 -0400 Date: Fri, 3 Jun 2016 21:01:51 +0200 From: Daniel Vetter To: Boris Brezillon Cc: Daniel Vetter , Laurent Pinchart , David Airlie , dri-devel , Daniel Vetter , Linux Kernel Mailing List , "linux-arm-kernel@lists.infradead.org" , Kukjin Kim , Krzysztof Kozlowski , linux-samsung-soc , intel-gfx , Jani Nikula , Alexey Brodkin , Inki Dae , Joonyoung Shim , Seung-Woo Kim , Kyungmin Park , Stefan Agner , Alison Wang , Matthias Brugger , Rob Clark , Mark Yao , Heiko Stuebner , Benjamin Gaignard , Vincent Abriou , Maxime Ripard , Chen-Yu Tsai , Thierry Re ding , Stephen Warren , Alexandre Courbot , Eric Anholt , Gerd Hoffmann , linux-mediatek@lists.infradead.org, linux-arm-msm , freedreno@lists.freedesktop.org, "open list:DRM DRIVERS FOR RENESAS" , "open list:ARM/Rockchip SoC..." , "linux-tegra@vger.kernel.org" , "open list:VIRTIO CORE, NET..." Subject: Re: [PATCH 01/20] drm/atomic: Fix remaining places where !funcs->best_encoder is valid Message-ID: <20160603190151.GD7231@phenom.ffwll.local> Mail-Followup-To: Boris Brezillon , Laurent Pinchart , David Airlie , dri-devel , Daniel Vetter , Linux Kernel Mailing List , "linux-arm-kernel@lists.infradead.org" , Kukjin Kim , Krzysztof Kozlowski , linux-samsung-soc , intel-gfx , Jani Nikula , Alexey Brodkin , Inki Dae , Joonyoung Shim , Seung-Woo Kim , Kyungmin Park , Stefan Agner , Alison Wang , Matthias Brugger , Rob Clark , Mark Yao , Heiko Stuebner , Benjamin Gaignard , Vincent Abriou , Maxime Ripard , Chen-Yu Tsai , Thierry Re ding , Stephen Warren , Alexandre Courbot , Eric Anholt , Gerd Hoffmann , linux-mediatek@lists.infradead.org, linux-arm-msm , freedreno@lists.freedesktop.org, "open list:DRM DRIVERS FOR RENESAS" , "open list:ARM/Rockchip SoC..." , "linux-tegra@vger.kernel.org" , "open list:VIRTIO CORE, NET..." References: <1464877907-27723-1-git-send-email-boris.brezillon@free-electrons.com> <1464877907-27723-2-git-send-email-boris.brezillon@free-electrons.com> <8671722.LHaiaBNqfE@avalon> <20160603093743.000ef95b@bbrezillon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160603093743.000ef95b@bbrezillon> X-Operating-System: Linux phenom 4.6.0-rc5+ User-Agent: Mutt/1.6.0 (2016-04-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 03, 2016 at 09:37:43AM +0200, Boris Brezillon wrote: > On Thu, 2 Jun 2016 23:57:02 +0200 > Daniel Vetter wrote: > > > On Thu, Jun 2, 2016 at 11:05 PM, Laurent Pinchart > > wrote: > > > Hi Boris, > > > > > > Thank you for the patch. > > > > > > On Thursday 02 Jun 2016 16:31:28 Boris Brezillon wrote: > > >> Adapt drm_pick_crtcs() and update_connector_routing() to fallback to > > >> drm_atomic_helper_best_encoder() if funcs->best_encoder() is NULL so > > >> that DRM drivers can leave this hook unassigned if they know they want > > >> to use drm_atomic_helper_best_encoder(). > > > > > > Could you please update include/drm/drm_modeset_helper_vtables.h to document > > > this new behaviour ? > > > > Thanks for reminding me. Please update hooks for both > > atomic_best_encoder and best_encoder. Also mention that it's only > > optional for atomic drivers. There's lots of examples in that file for > > the wording usually used. > > Hm, I haven't changed anything for the ->atomic_best_encoder() hook, or > am I missing something? Before you needed atomic_best_encoder or best_encoder (well that's the idea at least), now both are optional. Kerneldoc needs to be adjusted in both places to match new reality after your patch. -Daniel > > > > > > The only drawback I see in this patch is the additional object lookup > > > performed by drm_atomic_helper_best_encoder() at runtime. I wonder if we could > > > somehow cache the information, as the assignment can't change when there's a > > > 1:1 correspondence between encoders and connectors. > > > > drm_encoder_find is an idr lookup. That should be plenty fast, > > especially for modeset code. Usually what's too expensive even for > > modeset code is linear list walks. But Chris just submitted patches to > > convert most of them into simple lookups. > > -Daniel > > > > >>> Signed-off-by: Boris Brezillon > > >> --- > > >> drivers/gpu/drm/drm_atomic_helper.c | 4 +++- > > >> drivers/gpu/drm/drm_fb_helper.c | 13 ++++++++++++- > > >> 2 files changed, 15 insertions(+), 2 deletions(-) > > >> > > >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c > > >> b/drivers/gpu/drm/drm_atomic_helper.c index f6a3350..849d029 100644 > > >> --- a/drivers/gpu/drm/drm_atomic_helper.c > > >> +++ b/drivers/gpu/drm/drm_atomic_helper.c > > >> @@ -300,8 +300,10 @@ update_connector_routing(struct drm_atomic_state > > >> *state, if (funcs->atomic_best_encoder) > > >> new_encoder = funcs->atomic_best_encoder(connector, > > >> connector_state); > > >> - else > > >> + else if (funcs->best_encoder) > > >> new_encoder = funcs->best_encoder(connector); > > >> + else > > >> + new_encoder = drm_atomic_helper_best_encoder(connector); > > >> > > >> if (!new_encoder) { > > >> DRM_DEBUG_ATOMIC("No suitable encoder found for [CONNECTOR:%d:%s]\n", > > >> diff --git a/drivers/gpu/drm/drm_fb_helper.c > > >> b/drivers/gpu/drm/drm_fb_helper.c index 7c2eb75..d44389a 100644 > > >> --- a/drivers/gpu/drm/drm_fb_helper.c > > >> +++ b/drivers/gpu/drm/drm_fb_helper.c > > >> @@ -2000,7 +2000,18 @@ static int drm_pick_crtcs(struct drm_fb_helper > > >> *fb_helper, my_score++; > > >> > > >> connector_funcs = connector->helper_private; > > >> - encoder = connector_funcs->best_encoder(connector); > > >> + > > >> + /* > > >> + * If the DRM device implements atomic hooks and ->best_encoder() is > > >> + * NULL we fallback to the default drm_atomic_helper_best_encoder() > > >> + * helper. > > >> + */ > > >> + if (fb_helper->dev->mode_config.funcs->atomic_commit && > > >> + !connector_funcs->best_encoder) > > >> + encoder = drm_atomic_helper_best_encoder(connector); > > >> + else > > >> + encoder = connector_funcs->best_encoder(connector); > > >> + > > >> if (!encoder) > > >> goto out; > > > > > > -- > > > Regards, > > > > > > Laurent Pinchart > > > > > > > > > > > > > -- > Boris Brezillon, Free Electrons > Embedded Linux and Kernel engineering > http://free-electrons.com -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch