From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH v3 1/2] drm/file: Rehabilitate the firstopen hook for non-legacy drivers Date: Fri, 29 Mar 2019 09:37:52 +0100 Message-ID: <20190329083752.GD2665@phenom.ffwll.local> References: <20190328161306.22757-1-paul.kocialkowski@bootlin.com> <20190328161306.22757-2-paul.kocialkowski@bootlin.com> <20190329083534.GC2665@phenom.ffwll.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20190329083534.GC2665@phenom.ffwll.local> Sender: linux-kernel-owner@vger.kernel.org To: Paul Kocialkowski Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Maarten Lankhorst , Maxime Ripard , Sean Paul , David Airlie , Daniel Vetter , Eric Anholt , Eben Upton , Thomas Petazzoni List-Id: dri-devel@lists.freedesktop.org On Fri, Mar 29, 2019 at 09:35:34AM +0100, Daniel Vetter wrote: > On Thu, Mar 28, 2019 at 05:13:05PM +0100, Paul Kocialkowski wrote: > > The firstopen DRM driver hook was initially used to perform hardware > > initialization, which is now considered legacy. Only a single user of > > firstopen remains at this point (savage). > > > > In some specific cases, non-legacy drivers may also need to implement > > these hooks. For instance on VC4, we need to allocate a 16 MiB buffer > > for the GPU. Because it's not required for fbcon, it's a waste to > > allocate it before userspace starts using the DRM device. > > > > Using firstopen and lastclose for this allocation seems like the best > > fit, so re-habilitate the hook to allow it to be called for non-legacy > > drivers. > > > > Signed-off-by: Paul Kocialkowski > > Reviewed-by: Eric Anholt > > --- > > drivers/gpu/drm/drm_file.c | 3 +-- > > include/drm/drm_drv.h | 3 --- > > 2 files changed, 1 insertion(+), 5 deletions(-) > > > > diff --git a/drivers/gpu/drm/drm_file.c b/drivers/gpu/drm/drm_file.c > > index b1838a41ad43..c011b5cbfb6b 100644 > > --- a/drivers/gpu/drm/drm_file.c > > +++ b/drivers/gpu/drm/drm_file.c > > @@ -266,8 +266,7 @@ static int drm_setup(struct drm_device * dev) > > { > > int ret; > > > > - if (dev->driver->firstopen && > > - drm_core_check_feature(dev, DRIVER_LEGACY)) { > > + if (dev->driver->firstopen) { > > If you guys insist on this (still not a fan myself) pls pull it out of > drm_setup - that's all just legacy hw setup in there. I still think > tracking this a bit more accurately (if you want to bother with this) > would be better. Maybe another one: Firstopen is called after ->open, which might be confusing. But we can't change that ever because legacy drivers surely rely on that somewhere (like the backwards load/unload calling sequence). -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch