On Thu, May 26, 2016 at 11:02:55AM +0800, Ying Liu wrote: > On Wed, May 25, 2016 at 6:30 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > > On Wed, May 25, 2016 at 05:37:41PM +0800, Ying Liu wrote: > >> On Tue, May 24, 2016 at 6:57 PM, Daniel Vetter <daniel@xxxxxxxx> wrote: > >> > On Tue, May 24, 2016 at 06:10:44PM +0800, Liu Ying wrote: > >> >> Since CRTC has already been disabled in crtc_funcs->prepare(), it doesn't hurt > >> >> to disable the primary plane in drm_helper_crtc_mode_set() before enabling it > >> >> in drm_helper_crtc_mode_set_base(). This makes those who reject active plane > >> >> update in plane_funcs->atomic_check() happy. > >> > > >> > How/where exactly do you blow up? > >> >> > >> >> Signed-off-by: Liu Ying <gnuiyl@xxxxxxxxx> > >> >> --- > >> >> drivers/gpu/drm/drm_crtc_helper.c | 9 +++++++++ > >> >> 1 file changed, 9 insertions(+) > >> >> > >> >> diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c > >> >> index 79555d2..7fabcd7 100644 > >> >> --- a/drivers/gpu/drm/drm_crtc_helper.c > >> >> +++ b/drivers/gpu/drm/drm_crtc_helper.c > >> >> @@ -1013,6 +1013,15 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc, struct drm_display_mode *mod > >> >> goto out; > >> >> } > >> >> > >> >> + /* > >> >> + * It doesn't hurt to disable primary plane here since crtc is off > >> >> + * and we'll enable it again in drm_helper_crtc_mode_set_base() > >> >> + * below soon. > >> >> + */ > >> >> + ret = drm_plane_helper_disable(crtc->primary); > >> > > >> > You can't call this helper from crtc helpers. drm_plane_helper_disable > >> > assumes that a) you've already extracted universal plane support for the > >> > primary plane by registering a proper drm_plane for it b) that you're > >> > driver is at least partially using atomic hooks already. > >> > > >> > Both assumptions are wrong for all current users of this function. > >> > drm_helper_crtc_mode_set() is purely a legacy helper for legecy drivers. > >> > >> Isn't the function a transitional helper, just as the kdoc claims? > >> It looks all current users are sort of atomic users already. > > > > drm_helper_crtc_mode_set is exclusively used by legacy drivers. > > drm_plane_helper_disable can be used for transitioning to atomic. > > Again, please take a look at the kdoc of drm_helper_crtc_mode_set. > It reads 'Besides the atomic plane helper functions for the primary > plane the driver must also provide the ->mode_set_nofb callback > to set up the CRTC. This is a transitional helper useful for converting > drivers to the atomic interfaces.' Oops, my apologies, I mixed it all up in my head. Sorry for all the mess, I'll start a new thread since this discussion here is a bit confusion now. -Daniel > > Calling the latter from the former means you break every non-transition > > legacy driver. > > drm_helper_crtc_mode_set calls drm_helper_crtc_mode_set_base. > Both drm_helper_crtc_mode_set_base and drm_plane_helper_disable > call drm_plane_helper_commit, so they are somewhat counterparts, > that is to say, drm_helper_crtc_mode_set may call > drm_plane_helper_disable technically. > > Regards, > Liu Ying > > > -Daniel > > > >> > >> Regards, > >> Liu Ying > >> > >> > -Daniel > >> > > >> >> + if (ret) > >> >> + goto out; > >> >> + > >> >> swap(crtc->state, crtc_state); > >> >> > >> >> crtc_funcs->mode_set_nofb(crtc); > >> >> -- > >> >> 2.7.4 > >> >> > >> >> _______________________________________________ > >> >> dri-devel mailing list > >> >> dri-devel@xxxxxxxxxxxxxxxxxxxxx > >> >> https://lists.freedesktop.org/mailman/listinfo/dri-devel > >> > > >> > -- > >> > Daniel Vetter > >> > Software Engineer, Intel Corporation > >> > http://blog.ffwll.ch > > > > -- > > Daniel Vetter > > Software Engineer, Intel Corporation > > http://blog.ffwll.ch -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
