| Message ID | 559CD896.8040301@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > Op 07-07-15 om 18:43 schreef Daniel Vetter: > > On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>> which is useful for forcing a recalculation. > >>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>> way. What exactly do you need this for, what's the implications? > >>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>> the legacy entry points with atomic helpers, and then even plane_disable > >>> will be a full atomic modeset. > >>> > >>> What did fall apart with just touching properties/planes now? > >> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >> if a modeset is needed after the first atomic call. Right now because > >> intel_modeset_compute_config is only called in set_config so this works as expected. > >> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >> and if the final mode is different this will introduce a double modeset. > > For expensive properties (i.e. a no-op changes causes something that takes > > time like modeset or vblank wait) we need to make sure we filter them out > > in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > > the existing legacy set_prop functions should all filter out no-op changes > > themselves. If we don't do that for rotation then that's a bug. > > > > Same for disabling planes harder, that shouldn't take time. Especially > > since fbcon only force-disable non-primary plane, and for driver load > > that's the exact thing we already do in the driver anyway. > > Something like this? > --- > diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > index a1d4e13f3908..2989232f4996 100644 > --- a/drivers/gpu/drm/drm_atomic_helper.c > +++ b/drivers/gpu/drm/drm_atomic_helper.c > @@ -30,6 +30,7 @@ > #include <drm/drm_plane_helper.h> > #include <drm/drm_crtc_helper.h> > #include <drm/drm_atomic_helper.h> > +#include "drm_crtc_internal.h" > #include <linux/fence.h> > > /** > @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > { > struct drm_atomic_state *state; > struct drm_crtc_state *crtc_state; > - int ret = 0; > + uint64_t retval; > + int ret; > + > + ret = drm_atomic_get_property(&crtc->base, property, &retval); > + if (!ret && val == retval) > + return 0; > > state = drm_atomic_state_alloc(crtc->dev); > if (!state) > @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > { > struct drm_atomic_state *state; > struct drm_plane_state *plane_state; > - int ret = 0; > + uint64_t retval; > + int ret; > + > + ret = drm_atomic_get_property(&plane->base, property, &retval); > + if (!ret && val == retval) > + return 0; > > state = drm_atomic_state_alloc(plane->dev); > if (!state) > @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > { > struct drm_atomic_state *state; > struct drm_connector_state *connector_state; > - int ret = 0; > + uint64_t retval; > + int ret; > + > + ret = drm_atomic_get_property(&connector->base, property, &retval); > + if (!ret && val == retval) > + return 0; > > state = drm_atomic_state_alloc(connector->dev); > if (!state) The reason I didn't do this is that a prop change might still result in no hw state change (e.g. if you go automitic->explicit setting matching automatic one). Hence I think we need to solve this in lower levels anyway, i.e. in when computing the config. But it shouldn't cause trouble yet. > diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c > index 424c83323aaa..5bab7bff8a15 100644 > --- a/drivers/gpu/drm/drm_crtc.c > +++ b/drivers/gpu/drm/drm_crtc.c > @@ -1327,7 +1327,8 @@ void drm_plane_force_disable(struct drm_plane *plane) > { > int ret; > > - if (!plane->fb) > + if ((plane->state && !plane->state->fb) || > + (!plane->state && !plane->fb)) > return; Nah, atomic helpers should figure this out imo. Since if userspace does the same (loop over all planes) then it won't go through force_disable. -Daniel > > plane->old_fb = plane->fb; >
Op 08-07-15 om 10:55 schreef Daniel Vetter: > On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: >> Op 07-07-15 om 18:43 schreef Daniel Vetter: >>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: >>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: >>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: >>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: >>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: >>>>>>>> This allows the first atomic call during hw init to be a real modeset, >>>>>>>> which is useful for forcing a recalculation. >>>>>>> fbcon is optional, you can't rely on anything being done in any specific >>>>>>> way. What exactly do you need this for, what's the implications? >>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. >>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. >>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) >>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all >>>>> the legacy entry points with atomic helpers, and then even plane_disable >>>>> will be a full atomic modeset. >>>>> >>>>> What did fall apart with just touching properties/planes now? >>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config >>>> if a modeset is needed after the first atomic call. Right now because >>>> intel_modeset_compute_config is only called in set_config so this works as expected. >>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, >>>> and if the final mode is different this will introduce a double modeset. >>> For expensive properties (i.e. a no-op changes causes something that takes >>> time like modeset or vblank wait) we need to make sure we filter them out >>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile >>> the existing legacy set_prop functions should all filter out no-op changes >>> themselves. If we don't do that for rotation then that's a bug. >>> >>> Same for disabling planes harder, that shouldn't take time. Especially >>> since fbcon only force-disable non-primary plane, and for driver load >>> that's the exact thing we already do in the driver anyway. >> Something like this? >> --- >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c >> index a1d4e13f3908..2989232f4996 100644 >> --- a/drivers/gpu/drm/drm_atomic_helper.c >> +++ b/drivers/gpu/drm/drm_atomic_helper.c >> @@ -30,6 +30,7 @@ >> #include <drm/drm_plane_helper.h> >> #include <drm/drm_crtc_helper.h> >> #include <drm/drm_atomic_helper.h> >> +#include "drm_crtc_internal.h" >> #include <linux/fence.h> >> >> /** >> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, >> { >> struct drm_atomic_state *state; >> struct drm_crtc_state *crtc_state; >> - int ret = 0; >> + uint64_t retval; >> + int ret; >> + >> + ret = drm_atomic_get_property(&crtc->base, property, &retval); >> + if (!ret && val == retval) >> + return 0; >> >> state = drm_atomic_state_alloc(crtc->dev); >> if (!state) >> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, >> { >> struct drm_atomic_state *state; >> struct drm_plane_state *plane_state; >> - int ret = 0; >> + uint64_t retval; >> + int ret; >> + >> + ret = drm_atomic_get_property(&plane->base, property, &retval); >> + if (!ret && val == retval) >> + return 0; >> >> state = drm_atomic_state_alloc(plane->dev); >> if (!state) >> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, >> { >> struct drm_atomic_state *state; >> struct drm_connector_state *connector_state; >> - int ret = 0; >> + uint64_t retval; >> + int ret; >> + >> + ret = drm_atomic_get_property(&connector->base, property, &retval); >> + if (!ret && val == retval) >> + return 0; >> >> state = drm_atomic_state_alloc(connector->dev); >> if (!state) > The reason I didn't do this is that a prop change might still result in no > hw state change (e.g. if you go automitic->explicit setting matching > automatic one). Hence I think we need to solve this in lower levels > anyway, i.e. in when computing the config. But it shouldn't cause trouble > yet. Is that a ack or nack? >> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c >> index 424c83323aaa..5bab7bff8a15 100644 >> --- a/drivers/gpu/drm/drm_crtc.c >> +++ b/drivers/gpu/drm/drm_crtc.c >> @@ -1327,7 +1327,8 @@ void drm_plane_force_disable(struct drm_plane *plane) >> { >> int ret; >> >> - if (!plane->fb) >> + if ((plane->state && !plane->state->fb) || >> + (!plane->state && !plane->fb)) >> return; > Nah, atomic helpers should figure this out imo. Since if userspace does > the same (loop over all planes) then it won't go through force_disable. > -Daniel > >> >> plane->old_fb = plane->fb; >>
On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: > Op 08-07-15 om 10:55 schreef Daniel Vetter: > > On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > >> Op 07-07-15 om 18:43 schreef Daniel Vetter: > >>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>>>> which is useful for forcing a recalculation. > >>>>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>>>> way. What exactly do you need this for, what's the implications? > >>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>>>> the legacy entry points with atomic helpers, and then even plane_disable > >>>>> will be a full atomic modeset. > >>>>> > >>>>> What did fall apart with just touching properties/planes now? > >>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >>>> if a modeset is needed after the first atomic call. Right now because > >>>> intel_modeset_compute_config is only called in set_config so this works as expected. > >>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >>>> and if the final mode is different this will introduce a double modeset. > >>> For expensive properties (i.e. a no-op changes causes something that takes > >>> time like modeset or vblank wait) we need to make sure we filter them out > >>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > >>> the existing legacy set_prop functions should all filter out no-op changes > >>> themselves. If we don't do that for rotation then that's a bug. > >>> > >>> Same for disabling planes harder, that shouldn't take time. Especially > >>> since fbcon only force-disable non-primary plane, and for driver load > >>> that's the exact thing we already do in the driver anyway. > >> Something like this? > >> --- > >> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >> index a1d4e13f3908..2989232f4996 100644 > >> --- a/drivers/gpu/drm/drm_atomic_helper.c > >> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >> @@ -30,6 +30,7 @@ > >> #include <drm/drm_plane_helper.h> > >> #include <drm/drm_crtc_helper.h> > >> #include <drm/drm_atomic_helper.h> > >> +#include "drm_crtc_internal.h" > >> #include <linux/fence.h> > >> > >> /** > >> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > >> { > >> struct drm_atomic_state *state; > >> struct drm_crtc_state *crtc_state; > >> - int ret = 0; > >> + uint64_t retval; > >> + int ret; > >> + > >> + ret = drm_atomic_get_property(&crtc->base, property, &retval); > >> + if (!ret && val == retval) > >> + return 0; > >> > >> state = drm_atomic_state_alloc(crtc->dev); > >> if (!state) > >> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > >> { > >> struct drm_atomic_state *state; > >> struct drm_plane_state *plane_state; > >> - int ret = 0; > >> + uint64_t retval; > >> + int ret; > >> + > >> + ret = drm_atomic_get_property(&plane->base, property, &retval); > >> + if (!ret && val == retval) > >> + return 0; > >> > >> state = drm_atomic_state_alloc(plane->dev); > >> if (!state) > >> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > >> { > >> struct drm_atomic_state *state; > >> struct drm_connector_state *connector_state; > >> - int ret = 0; > >> + uint64_t retval; > >> + int ret; > >> + > >> + ret = drm_atomic_get_property(&connector->base, property, &retval); > >> + if (!ret && val == retval) > >> + return 0; > >> > >> state = drm_atomic_state_alloc(connector->dev); > >> if (!state) > > The reason I didn't do this is that a prop change might still result in no > > hw state change (e.g. if you go automitic->explicit setting matching > > automatic one). Hence I think we need to solve this in lower levels > > anyway, i.e. in when computing the config. But it shouldn't cause trouble > > yet. > Is that a ack or nack? I think we shouldn't need this really for i915, and it might cover up bugs. I prefer we just do the evade modeset logic you've implemented once we switch over to atomic props. Since atm we only have atomic props which get updated in pageflips we shouldn't have serious problems here yet (for setting the rotation prop to 0° again when fbdev starts up). Or do I miss something still here? -Daniel
Op 08-07-15 om 19:52 schreef Daniel Vetter: > On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: >> Op 08-07-15 om 10:55 schreef Daniel Vetter: >>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: >>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: >>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: >>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: >>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: >>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: >>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: >>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, >>>>>>>>>> which is useful for forcing a recalculation. >>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific >>>>>>>>> way. What exactly do you need this for, what's the implications? >>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. >>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. >>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) >>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all >>>>>>> the legacy entry points with atomic helpers, and then even plane_disable >>>>>>> will be a full atomic modeset. >>>>>>> >>>>>>> What did fall apart with just touching properties/planes now? >>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config >>>>>> if a modeset is needed after the first atomic call. Right now because >>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. >>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, >>>>>> and if the final mode is different this will introduce a double modeset. >>>>> For expensive properties (i.e. a no-op changes causes something that takes >>>>> time like modeset or vblank wait) we need to make sure we filter them out >>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile >>>>> the existing legacy set_prop functions should all filter out no-op changes >>>>> themselves. If we don't do that for rotation then that's a bug. >>>>> >>>>> Same for disabling planes harder, that shouldn't take time. Especially >>>>> since fbcon only force-disable non-primary plane, and for driver load >>>>> that's the exact thing we already do in the driver anyway. >>>> Something like this? >>>> --- >>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c >>>> index a1d4e13f3908..2989232f4996 100644 >>>> --- a/drivers/gpu/drm/drm_atomic_helper.c >>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c >>>> @@ -30,6 +30,7 @@ >>>> #include <drm/drm_plane_helper.h> >>>> #include <drm/drm_crtc_helper.h> >>>> #include <drm/drm_atomic_helper.h> >>>> +#include "drm_crtc_internal.h" >>>> #include <linux/fence.h> >>>> >>>> /** >>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, >>>> { >>>> struct drm_atomic_state *state; >>>> struct drm_crtc_state *crtc_state; >>>> - int ret = 0; >>>> + uint64_t retval; >>>> + int ret; >>>> + >>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); >>>> + if (!ret && val == retval) >>>> + return 0; >>>> >>>> state = drm_atomic_state_alloc(crtc->dev); >>>> if (!state) >>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, >>>> { >>>> struct drm_atomic_state *state; >>>> struct drm_plane_state *plane_state; >>>> - int ret = 0; >>>> + uint64_t retval; >>>> + int ret; >>>> + >>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); >>>> + if (!ret && val == retval) >>>> + return 0; >>>> >>>> state = drm_atomic_state_alloc(plane->dev); >>>> if (!state) >>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, >>>> { >>>> struct drm_atomic_state *state; >>>> struct drm_connector_state *connector_state; >>>> - int ret = 0; >>>> + uint64_t retval; >>>> + int ret; >>>> + >>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); >>>> + if (!ret && val == retval) >>>> + return 0; >>>> >>>> state = drm_atomic_state_alloc(connector->dev); >>>> if (!state) >>> The reason I didn't do this is that a prop change might still result in no >>> hw state change (e.g. if you go automitic->explicit setting matching >>> automatic one). Hence I think we need to solve this in lower levels >>> anyway, i.e. in when computing the config. But it shouldn't cause trouble >>> yet. >> Is that a ack or nack? > I think we shouldn't need this really for i915, and it might cover up > bugs. I prefer we just do the evade modeset logic you've implemented once > we switch over to atomic props. Since atm we only have atomic props which > get updated in pageflips we shouldn't have serious problems here yet (for > setting the rotation prop to 0° again when fbdev starts up). > > Or do I miss something still here? Yes, if the hardware mode is incompatible with its calculated sw mode, and we set a different mode from fbdev you get 2 modesets instead of 1. First to make the mode compatible because of the rotate_0, second to set the new mode. ~Maarten
On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: > Op 08-07-15 om 19:52 schreef Daniel Vetter: > > On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: > >> Op 08-07-15 om 10:55 schreef Daniel Vetter: > >>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > >>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: > >>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>>>>>> which is useful for forcing a recalculation. > >>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>>>>>> way. What exactly do you need this for, what's the implications? > >>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>>>>>> the legacy entry points with atomic helpers, and then even plane_disable > >>>>>>> will be a full atomic modeset. > >>>>>>> > >>>>>>> What did fall apart with just touching properties/planes now? > >>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >>>>>> if a modeset is needed after the first atomic call. Right now because > >>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. > >>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >>>>>> and if the final mode is different this will introduce a double modeset. > >>>>> For expensive properties (i.e. a no-op changes causes something that takes > >>>>> time like modeset or vblank wait) we need to make sure we filter them out > >>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > >>>>> the existing legacy set_prop functions should all filter out no-op changes > >>>>> themselves. If we don't do that for rotation then that's a bug. > >>>>> > >>>>> Same for disabling planes harder, that shouldn't take time. Especially > >>>>> since fbcon only force-disable non-primary plane, and for driver load > >>>>> that's the exact thing we already do in the driver anyway. > >>>> Something like this? > >>>> --- > >>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >>>> index a1d4e13f3908..2989232f4996 100644 > >>>> --- a/drivers/gpu/drm/drm_atomic_helper.c > >>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >>>> @@ -30,6 +30,7 @@ > >>>> #include <drm/drm_plane_helper.h> > >>>> #include <drm/drm_crtc_helper.h> > >>>> #include <drm/drm_atomic_helper.h> > >>>> +#include "drm_crtc_internal.h" > >>>> #include <linux/fence.h> > >>>> > >>>> /** > >>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > >>>> { > >>>> struct drm_atomic_state *state; > >>>> struct drm_crtc_state *crtc_state; > >>>> - int ret = 0; > >>>> + uint64_t retval; > >>>> + int ret; > >>>> + > >>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); > >>>> + if (!ret && val == retval) > >>>> + return 0; > >>>> > >>>> state = drm_atomic_state_alloc(crtc->dev); > >>>> if (!state) > >>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > >>>> { > >>>> struct drm_atomic_state *state; > >>>> struct drm_plane_state *plane_state; > >>>> - int ret = 0; > >>>> + uint64_t retval; > >>>> + int ret; > >>>> + > >>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); > >>>> + if (!ret && val == retval) > >>>> + return 0; > >>>> > >>>> state = drm_atomic_state_alloc(plane->dev); > >>>> if (!state) > >>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > >>>> { > >>>> struct drm_atomic_state *state; > >>>> struct drm_connector_state *connector_state; > >>>> - int ret = 0; > >>>> + uint64_t retval; > >>>> + int ret; > >>>> + > >>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); > >>>> + if (!ret && val == retval) > >>>> + return 0; > >>>> > >>>> state = drm_atomic_state_alloc(connector->dev); > >>>> if (!state) > >>> The reason I didn't do this is that a prop change might still result in no > >>> hw state change (e.g. if you go automitic->explicit setting matching > >>> automatic one). Hence I think we need to solve this in lower levels > >>> anyway, i.e. in when computing the config. But it shouldn't cause trouble > >>> yet. > >> Is that a ack or nack? > > I think we shouldn't need this really for i915, and it might cover up > > bugs. I prefer we just do the evade modeset logic you've implemented once > > we switch over to atomic props. Since atm we only have atomic props which > > get updated in pageflips we shouldn't have serious problems here yet (for > > setting the rotation prop to 0° again when fbdev starts up). > > > > Or do I miss something still here? > Yes, if the hardware mode is incompatible with its calculated sw mode, > and we set a different mode from fbdev you get 2 modesets instead of 1. How does that happen? For setting the rotation property we should just duplicate the current crtc state. Since there's no mode changing (they should match perfectly no matter how botched the reconstruction is) there shouldn't be any need to recompute the config completely and discover that there's a mismatch. Which means we'll just do the plane update (which might do a few silly mmios but shouldn't block) and that's it. At least that's what I'd expect - where does this fall apart? -Daniel
Op 08-07-15 om 22:12 schreef Daniel Vetter: > On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: >> Op 08-07-15 om 19:52 schreef Daniel Vetter: >>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: >>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: >>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: >>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: >>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: >>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: >>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: >>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: >>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, >>>>>>>>>>>> which is useful for forcing a recalculation. >>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific >>>>>>>>>>> way. What exactly do you need this for, what's the implications? >>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. >>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. >>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) >>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all >>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable >>>>>>>>> will be a full atomic modeset. >>>>>>>>> >>>>>>>>> What did fall apart with just touching properties/planes now? >>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config >>>>>>>> if a modeset is needed after the first atomic call. Right now because >>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. >>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, >>>>>>>> and if the final mode is different this will introduce a double modeset. >>>>>>> For expensive properties (i.e. a no-op changes causes something that takes >>>>>>> time like modeset or vblank wait) we need to make sure we filter them out >>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile >>>>>>> the existing legacy set_prop functions should all filter out no-op changes >>>>>>> themselves. If we don't do that for rotation then that's a bug. >>>>>>> >>>>>>> Same for disabling planes harder, that shouldn't take time. Especially >>>>>>> since fbcon only force-disable non-primary plane, and for driver load >>>>>>> that's the exact thing we already do in the driver anyway. >>>>>> Something like this? >>>>>> --- >>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c >>>>>> index a1d4e13f3908..2989232f4996 100644 >>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c >>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c >>>>>> @@ -30,6 +30,7 @@ >>>>>> #include <drm/drm_plane_helper.h> >>>>>> #include <drm/drm_crtc_helper.h> >>>>>> #include <drm/drm_atomic_helper.h> >>>>>> +#include "drm_crtc_internal.h" >>>>>> #include <linux/fence.h> >>>>>> >>>>>> /** >>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, >>>>>> { >>>>>> struct drm_atomic_state *state; >>>>>> struct drm_crtc_state *crtc_state; >>>>>> - int ret = 0; >>>>>> + uint64_t retval; >>>>>> + int ret; >>>>>> + >>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); >>>>>> + if (!ret && val == retval) >>>>>> + return 0; >>>>>> >>>>>> state = drm_atomic_state_alloc(crtc->dev); >>>>>> if (!state) >>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, >>>>>> { >>>>>> struct drm_atomic_state *state; >>>>>> struct drm_plane_state *plane_state; >>>>>> - int ret = 0; >>>>>> + uint64_t retval; >>>>>> + int ret; >>>>>> + >>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); >>>>>> + if (!ret && val == retval) >>>>>> + return 0; >>>>>> >>>>>> state = drm_atomic_state_alloc(plane->dev); >>>>>> if (!state) >>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, >>>>>> { >>>>>> struct drm_atomic_state *state; >>>>>> struct drm_connector_state *connector_state; >>>>>> - int ret = 0; >>>>>> + uint64_t retval; >>>>>> + int ret; >>>>>> + >>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); >>>>>> + if (!ret && val == retval) >>>>>> + return 0; >>>>>> >>>>>> state = drm_atomic_state_alloc(connector->dev); >>>>>> if (!state) >>>>> The reason I didn't do this is that a prop change might still result in no >>>>> hw state change (e.g. if you go automitic->explicit setting matching >>>>> automatic one). Hence I think we need to solve this in lower levels >>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble >>>>> yet. >>>> Is that a ack or nack? >>> I think we shouldn't need this really for i915, and it might cover up >>> bugs. I prefer we just do the evade modeset logic you've implemented once >>> we switch over to atomic props. Since atm we only have atomic props which >>> get updated in pageflips we shouldn't have serious problems here yet (for >>> setting the rotation prop to 0° again when fbdev starts up). >>> >>> Or do I miss something still here? >> Yes, if the hardware mode is incompatible with its calculated sw mode, >> and we set a different mode from fbdev you get 2 modesets instead of 1. > How does that happen? For setting the rotation property we should just > duplicate the current crtc state. Since there's no mode changing (they > should match perfectly no matter how botched the reconstruction is) there > shouldn't be any need to recompute the config completely and discover that > there's a mismatch. Which means we'll just do the plane update (which > might do a few silly mmios but shouldn't block) and that's it. > > At least that's what I'd expect - where does this fall apart? If crtc is active and primary fb visible, and converted to atomic: restore_fbdev_mode() -> drm_mode_plane_set_obj_prop() -> drm_atomic_helper_plane_set_property() -> drm_atomic_get_plane_state() -> drm_atomic_get_crtc_state() crtc state is part of the state, intel_modeset_pipe_config performs the initial check if modeset's needed. Lets assume yes: modeset() drm_mode_set_config_internal() -> modeset() Boom double modeset. :( The alternative solution is making a atomic version of restore_fbdev_mode, but that would break drivers that are only partially converted to atomic, like i915 with i915.nuclear_pageflip=true before the convert to atomic commit. ~Maarten
On Mon, Jul 13, 2015 at 10:59:32AM +0200, Maarten Lankhorst wrote: > Op 08-07-15 om 22:12 schreef Daniel Vetter: > > On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: > >> Op 08-07-15 om 19:52 schreef Daniel Vetter: > >>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: > >>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: > >>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > >>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: > >>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>>>>>>>> which is useful for forcing a recalculation. > >>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>>>>>>>> way. What exactly do you need this for, what's the implications? > >>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable > >>>>>>>>> will be a full atomic modeset. > >>>>>>>>> > >>>>>>>>> What did fall apart with just touching properties/planes now? > >>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >>>>>>>> if a modeset is needed after the first atomic call. Right now because > >>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. > >>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >>>>>>>> and if the final mode is different this will introduce a double modeset. > >>>>>>> For expensive properties (i.e. a no-op changes causes something that takes > >>>>>>> time like modeset or vblank wait) we need to make sure we filter them out > >>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > >>>>>>> the existing legacy set_prop functions should all filter out no-op changes > >>>>>>> themselves. If we don't do that for rotation then that's a bug. > >>>>>>> > >>>>>>> Same for disabling planes harder, that shouldn't take time. Especially > >>>>>>> since fbcon only force-disable non-primary plane, and for driver load > >>>>>>> that's the exact thing we already do in the driver anyway. > >>>>>> Something like this? > >>>>>> --- > >>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>> index a1d4e13f3908..2989232f4996 100644 > >>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c > >>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>> @@ -30,6 +30,7 @@ > >>>>>> #include <drm/drm_plane_helper.h> > >>>>>> #include <drm/drm_crtc_helper.h> > >>>>>> #include <drm/drm_atomic_helper.h> > >>>>>> +#include "drm_crtc_internal.h" > >>>>>> #include <linux/fence.h> > >>>>>> > >>>>>> /** > >>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > >>>>>> { > >>>>>> struct drm_atomic_state *state; > >>>>>> struct drm_crtc_state *crtc_state; > >>>>>> - int ret = 0; > >>>>>> + uint64_t retval; > >>>>>> + int ret; > >>>>>> + > >>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); > >>>>>> + if (!ret && val == retval) > >>>>>> + return 0; > >>>>>> > >>>>>> state = drm_atomic_state_alloc(crtc->dev); > >>>>>> if (!state) > >>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > >>>>>> { > >>>>>> struct drm_atomic_state *state; > >>>>>> struct drm_plane_state *plane_state; > >>>>>> - int ret = 0; > >>>>>> + uint64_t retval; > >>>>>> + int ret; > >>>>>> + > >>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); > >>>>>> + if (!ret && val == retval) > >>>>>> + return 0; > >>>>>> > >>>>>> state = drm_atomic_state_alloc(plane->dev); > >>>>>> if (!state) > >>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > >>>>>> { > >>>>>> struct drm_atomic_state *state; > >>>>>> struct drm_connector_state *connector_state; > >>>>>> - int ret = 0; > >>>>>> + uint64_t retval; > >>>>>> + int ret; > >>>>>> + > >>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); > >>>>>> + if (!ret && val == retval) > >>>>>> + return 0; > >>>>>> > >>>>>> state = drm_atomic_state_alloc(connector->dev); > >>>>>> if (!state) > >>>>> The reason I didn't do this is that a prop change might still result in no > >>>>> hw state change (e.g. if you go automitic->explicit setting matching > >>>>> automatic one). Hence I think we need to solve this in lower levels > >>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble > >>>>> yet. > >>>> Is that a ack or nack? > >>> I think we shouldn't need this really for i915, and it might cover up > >>> bugs. I prefer we just do the evade modeset logic you've implemented once > >>> we switch over to atomic props. Since atm we only have atomic props which > >>> get updated in pageflips we shouldn't have serious problems here yet (for > >>> setting the rotation prop to 0° again when fbdev starts up). > >>> > >>> Or do I miss something still here? > >> Yes, if the hardware mode is incompatible with its calculated sw mode, > >> and we set a different mode from fbdev you get 2 modesets instead of 1. > > How does that happen? For setting the rotation property we should just > > duplicate the current crtc state. Since there's no mode changing (they > > should match perfectly no matter how botched the reconstruction is) there > > shouldn't be any need to recompute the config completely and discover that > > there's a mismatch. Which means we'll just do the plane update (which > > might do a few silly mmios but shouldn't block) and that's it. > > > > At least that's what I'd expect - where does this fall apart? > If crtc is active and primary fb visible, and converted to atomic: > > restore_fbdev_mode() -> > drm_mode_plane_set_obj_prop() -> > drm_atomic_helper_plane_set_property() -> > drm_atomic_get_plane_state() -> > drm_atomic_get_crtc_state() > crtc state is part of the state, intel_modeset_pipe_config performs > the initial check if modeset's needed. Lets assume yes: "Let's assume yes" -> that's imo a bug, so where does this happen so that we can fix it? Disabling a plane or setting a plane prop really shouldn't result in a modeset. Well at least if it's not a plane prop that does required a modeset (but I don't think we have any of those). -Daniel
Op 13-07-15 om 11:13 schreef Daniel Vetter: > On Mon, Jul 13, 2015 at 10:59:32AM +0200, Maarten Lankhorst wrote: >> Op 08-07-15 om 22:12 schreef Daniel Vetter: >>> On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: >>>> Op 08-07-15 om 19:52 schreef Daniel Vetter: >>>>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: >>>>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: >>>>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: >>>>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: >>>>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: >>>>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: >>>>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: >>>>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, >>>>>>>>>>>>>> which is useful for forcing a recalculation. >>>>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific >>>>>>>>>>>>> way. What exactly do you need this for, what's the implications? >>>>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. >>>>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. >>>>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) >>>>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all >>>>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable >>>>>>>>>>> will be a full atomic modeset. >>>>>>>>>>> >>>>>>>>>>> What did fall apart with just touching properties/planes now? >>>>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config >>>>>>>>>> if a modeset is needed after the first atomic call. Right now because >>>>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. >>>>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, >>>>>>>>>> and if the final mode is different this will introduce a double modeset. >>>>>>>>> For expensive properties (i.e. a no-op changes causes something that takes >>>>>>>>> time like modeset or vblank wait) we need to make sure we filter them out >>>>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile >>>>>>>>> the existing legacy set_prop functions should all filter out no-op changes >>>>>>>>> themselves. If we don't do that for rotation then that's a bug. >>>>>>>>> >>>>>>>>> Same for disabling planes harder, that shouldn't take time. Especially >>>>>>>>> since fbcon only force-disable non-primary plane, and for driver load >>>>>>>>> that's the exact thing we already do in the driver anyway. >>>>>>>> Something like this? >>>>>>>> --- >>>>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>> index a1d4e13f3908..2989232f4996 100644 >>>>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>> @@ -30,6 +30,7 @@ >>>>>>>> #include <drm/drm_plane_helper.h> >>>>>>>> #include <drm/drm_crtc_helper.h> >>>>>>>> #include <drm/drm_atomic_helper.h> >>>>>>>> +#include "drm_crtc_internal.h" >>>>>>>> #include <linux/fence.h> >>>>>>>> >>>>>>>> /** >>>>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, >>>>>>>> { >>>>>>>> struct drm_atomic_state *state; >>>>>>>> struct drm_crtc_state *crtc_state; >>>>>>>> - int ret = 0; >>>>>>>> + uint64_t retval; >>>>>>>> + int ret; >>>>>>>> + >>>>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); >>>>>>>> + if (!ret && val == retval) >>>>>>>> + return 0; >>>>>>>> >>>>>>>> state = drm_atomic_state_alloc(crtc->dev); >>>>>>>> if (!state) >>>>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, >>>>>>>> { >>>>>>>> struct drm_atomic_state *state; >>>>>>>> struct drm_plane_state *plane_state; >>>>>>>> - int ret = 0; >>>>>>>> + uint64_t retval; >>>>>>>> + int ret; >>>>>>>> + >>>>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); >>>>>>>> + if (!ret && val == retval) >>>>>>>> + return 0; >>>>>>>> >>>>>>>> state = drm_atomic_state_alloc(plane->dev); >>>>>>>> if (!state) >>>>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, >>>>>>>> { >>>>>>>> struct drm_atomic_state *state; >>>>>>>> struct drm_connector_state *connector_state; >>>>>>>> - int ret = 0; >>>>>>>> + uint64_t retval; >>>>>>>> + int ret; >>>>>>>> + >>>>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); >>>>>>>> + if (!ret && val == retval) >>>>>>>> + return 0; >>>>>>>> >>>>>>>> state = drm_atomic_state_alloc(connector->dev); >>>>>>>> if (!state) >>>>>>> The reason I didn't do this is that a prop change might still result in no >>>>>>> hw state change (e.g. if you go automitic->explicit setting matching >>>>>>> automatic one). Hence I think we need to solve this in lower levels >>>>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble >>>>>>> yet. >>>>>> Is that a ack or nack? >>>>> I think we shouldn't need this really for i915, and it might cover up >>>>> bugs. I prefer we just do the evade modeset logic you've implemented once >>>>> we switch over to atomic props. Since atm we only have atomic props which >>>>> get updated in pageflips we shouldn't have serious problems here yet (for >>>>> setting the rotation prop to 0° again when fbdev starts up). >>>>> >>>>> Or do I miss something still here? >>>> Yes, if the hardware mode is incompatible with its calculated sw mode, >>>> and we set a different mode from fbdev you get 2 modesets instead of 1. >>> How does that happen? For setting the rotation property we should just >>> duplicate the current crtc state. Since there's no mode changing (they >>> should match perfectly no matter how botched the reconstruction is) there >>> shouldn't be any need to recompute the config completely and discover that >>> there's a mismatch. Which means we'll just do the plane update (which >>> might do a few silly mmios but shouldn't block) and that's it. >>> >>> At least that's what I'd expect - where does this fall apart? >> If crtc is active and primary fb visible, and converted to atomic: >> >> restore_fbdev_mode() -> >> drm_mode_plane_set_obj_prop() -> >> drm_atomic_helper_plane_set_property() -> >> drm_atomic_get_plane_state() -> >> drm_atomic_get_crtc_state() >> crtc state is part of the state, intel_modeset_pipe_config performs >> the initial check if modeset's needed. Lets assume yes: > "Let's assume yes" -> that's imo a bug, so where does this happen so that > we can fix it? Disabling a plane or setting a plane prop really shouldn't > result in a modeset. Well at least if it's not a plane prop that does > required a modeset (but I don't think we have any of those). From a driver point of view you wouldn't be able to distinguish it from a real modeset to the same mode. :( In both cases you have all planes added and the crtc. Thinking about it more there will be 1 thing saving us from a modeset, drm_atomic_crtc_check will reject enable without mode_blob for atomic drivers, so until the first mode is set all atomic updates to the crtc will be rejected. Unfortunately you will still get WARN_ON's for this, so a better solution's needed. ~Maarten
On Mon, Jul 13, 2015 at 11:23:45AM +0200, Maarten Lankhorst wrote: > Op 13-07-15 om 11:13 schreef Daniel Vetter: > > On Mon, Jul 13, 2015 at 10:59:32AM +0200, Maarten Lankhorst wrote: > >> Op 08-07-15 om 22:12 schreef Daniel Vetter: > >>> On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: > >>>> Op 08-07-15 om 19:52 schreef Daniel Vetter: > >>>>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: > >>>>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: > >>>>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > >>>>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: > >>>>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >>>>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>>>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>>>>>>>>>> which is useful for forcing a recalculation. > >>>>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>>>>>>>>>> way. What exactly do you need this for, what's the implications? > >>>>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>>>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>>>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable > >>>>>>>>>>> will be a full atomic modeset. > >>>>>>>>>>> > >>>>>>>>>>> What did fall apart with just touching properties/planes now? > >>>>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >>>>>>>>>> if a modeset is needed after the first atomic call. Right now because > >>>>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. > >>>>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >>>>>>>>>> and if the final mode is different this will introduce a double modeset. > >>>>>>>>> For expensive properties (i.e. a no-op changes causes something that takes > >>>>>>>>> time like modeset or vblank wait) we need to make sure we filter them out > >>>>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > >>>>>>>>> the existing legacy set_prop functions should all filter out no-op changes > >>>>>>>>> themselves. If we don't do that for rotation then that's a bug. > >>>>>>>>> > >>>>>>>>> Same for disabling planes harder, that shouldn't take time. Especially > >>>>>>>>> since fbcon only force-disable non-primary plane, and for driver load > >>>>>>>>> that's the exact thing we already do in the driver anyway. > >>>>>>>> Something like this? > >>>>>>>> --- > >>>>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>> index a1d4e13f3908..2989232f4996 100644 > >>>>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>> @@ -30,6 +30,7 @@ > >>>>>>>> #include <drm/drm_plane_helper.h> > >>>>>>>> #include <drm/drm_crtc_helper.h> > >>>>>>>> #include <drm/drm_atomic_helper.h> > >>>>>>>> +#include "drm_crtc_internal.h" > >>>>>>>> #include <linux/fence.h> > >>>>>>>> > >>>>>>>> /** > >>>>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > >>>>>>>> { > >>>>>>>> struct drm_atomic_state *state; > >>>>>>>> struct drm_crtc_state *crtc_state; > >>>>>>>> - int ret = 0; > >>>>>>>> + uint64_t retval; > >>>>>>>> + int ret; > >>>>>>>> + > >>>>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); > >>>>>>>> + if (!ret && val == retval) > >>>>>>>> + return 0; > >>>>>>>> > >>>>>>>> state = drm_atomic_state_alloc(crtc->dev); > >>>>>>>> if (!state) > >>>>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > >>>>>>>> { > >>>>>>>> struct drm_atomic_state *state; > >>>>>>>> struct drm_plane_state *plane_state; > >>>>>>>> - int ret = 0; > >>>>>>>> + uint64_t retval; > >>>>>>>> + int ret; > >>>>>>>> + > >>>>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); > >>>>>>>> + if (!ret && val == retval) > >>>>>>>> + return 0; > >>>>>>>> > >>>>>>>> state = drm_atomic_state_alloc(plane->dev); > >>>>>>>> if (!state) > >>>>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > >>>>>>>> { > >>>>>>>> struct drm_atomic_state *state; > >>>>>>>> struct drm_connector_state *connector_state; > >>>>>>>> - int ret = 0; > >>>>>>>> + uint64_t retval; > >>>>>>>> + int ret; > >>>>>>>> + > >>>>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); > >>>>>>>> + if (!ret && val == retval) > >>>>>>>> + return 0; > >>>>>>>> > >>>>>>>> state = drm_atomic_state_alloc(connector->dev); > >>>>>>>> if (!state) > >>>>>>> The reason I didn't do this is that a prop change might still result in no > >>>>>>> hw state change (e.g. if you go automitic->explicit setting matching > >>>>>>> automatic one). Hence I think we need to solve this in lower levels > >>>>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble > >>>>>>> yet. > >>>>>> Is that a ack or nack? > >>>>> I think we shouldn't need this really for i915, and it might cover up > >>>>> bugs. I prefer we just do the evade modeset logic you've implemented once > >>>>> we switch over to atomic props. Since atm we only have atomic props which > >>>>> get updated in pageflips we shouldn't have serious problems here yet (for > >>>>> setting the rotation prop to 0° again when fbdev starts up). > >>>>> > >>>>> Or do I miss something still here? > >>>> Yes, if the hardware mode is incompatible with its calculated sw mode, > >>>> and we set a different mode from fbdev you get 2 modesets instead of 1. > >>> How does that happen? For setting the rotation property we should just > >>> duplicate the current crtc state. Since there's no mode changing (they > >>> should match perfectly no matter how botched the reconstruction is) there > >>> shouldn't be any need to recompute the config completely and discover that > >>> there's a mismatch. Which means we'll just do the plane update (which > >>> might do a few silly mmios but shouldn't block) and that's it. > >>> > >>> At least that's what I'd expect - where does this fall apart? > >> If crtc is active and primary fb visible, and converted to atomic: > >> > >> restore_fbdev_mode() -> > >> drm_mode_plane_set_obj_prop() -> > >> drm_atomic_helper_plane_set_property() -> > >> drm_atomic_get_plane_state() -> > >> drm_atomic_get_crtc_state() > >> crtc state is part of the state, intel_modeset_pipe_config performs > >> the initial check if modeset's needed. Lets assume yes: > > "Let's assume yes" -> that's imo a bug, so where does this happen so that > > we can fix it? Disabling a plane or setting a plane prop really shouldn't > > result in a modeset. Well at least if it's not a plane prop that does > > required a modeset (but I don't think we have any of those). > From a driver point of view you wouldn't be able to distinguish it from a real modeset to the same mode. :( > In both cases you have all planes added and the crtc. > > Thinking about it more there will be 1 thing saving us from a modeset, > drm_atomic_crtc_check will reject enable without mode_blob for atomic drivers, > so until the first mode is set all atomic updates to the crtc will be rejected. > > Unfortunately you will still get WARN_ON's for this, so a better solution's needed. Ok I think I start to grasp what's wrong, the trouble is that we don't have the mode stuff fully set up yet (which is part of fastboot), which means we'll get a bogus crtc_state->mode_changed despite that nothing really changed. Ugly. Could we insert a dummy mode_blob to avoid the WARNs and the bogus mode_changed instead? The problem really is that doing this here is just plugging the one source of troubles you're seeing right now (fbcon), the initial set_* calls could come from anything really in any order. So we really better be able to cope. Even converting fbdev to have an optional atomic patch for DRIVER_ATOMIC (unsafe i915 options aren't a concern here for me) won't fix this. -Daniel
Op 13-07-15 om 11:45 schreef Daniel Vetter: > On Mon, Jul 13, 2015 at 11:23:45AM +0200, Maarten Lankhorst wrote: >> Op 13-07-15 om 11:13 schreef Daniel Vetter: >>> On Mon, Jul 13, 2015 at 10:59:32AM +0200, Maarten Lankhorst wrote: >>>> Op 08-07-15 om 22:12 schreef Daniel Vetter: >>>>> On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: >>>>>> Op 08-07-15 om 19:52 schreef Daniel Vetter: >>>>>>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: >>>>>>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: >>>>>>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: >>>>>>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: >>>>>>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: >>>>>>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: >>>>>>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: >>>>>>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, >>>>>>>>>>>>>>>> which is useful for forcing a recalculation. >>>>>>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific >>>>>>>>>>>>>>> way. What exactly do you need this for, what's the implications? >>>>>>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. >>>>>>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. >>>>>>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) >>>>>>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all >>>>>>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable >>>>>>>>>>>>> will be a full atomic modeset. >>>>>>>>>>>>> >>>>>>>>>>>>> What did fall apart with just touching properties/planes now? >>>>>>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config >>>>>>>>>>>> if a modeset is needed after the first atomic call. Right now because >>>>>>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. >>>>>>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, >>>>>>>>>>>> and if the final mode is different this will introduce a double modeset. >>>>>>>>>>> For expensive properties (i.e. a no-op changes causes something that takes >>>>>>>>>>> time like modeset or vblank wait) we need to make sure we filter them out >>>>>>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile >>>>>>>>>>> the existing legacy set_prop functions should all filter out no-op changes >>>>>>>>>>> themselves. If we don't do that for rotation then that's a bug. >>>>>>>>>>> >>>>>>>>>>> Same for disabling planes harder, that shouldn't take time. Especially >>>>>>>>>>> since fbcon only force-disable non-primary plane, and for driver load >>>>>>>>>>> that's the exact thing we already do in the driver anyway. >>>>>>>>>> Something like this? >>>>>>>>>> --- >>>>>>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>>>> index a1d4e13f3908..2989232f4996 100644 >>>>>>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c >>>>>>>>>> @@ -30,6 +30,7 @@ >>>>>>>>>> #include <drm/drm_plane_helper.h> >>>>>>>>>> #include <drm/drm_crtc_helper.h> >>>>>>>>>> #include <drm/drm_atomic_helper.h> >>>>>>>>>> +#include "drm_crtc_internal.h" >>>>>>>>>> #include <linux/fence.h> >>>>>>>>>> >>>>>>>>>> /** >>>>>>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, >>>>>>>>>> { >>>>>>>>>> struct drm_atomic_state *state; >>>>>>>>>> struct drm_crtc_state *crtc_state; >>>>>>>>>> - int ret = 0; >>>>>>>>>> + uint64_t retval; >>>>>>>>>> + int ret; >>>>>>>>>> + >>>>>>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); >>>>>>>>>> + if (!ret && val == retval) >>>>>>>>>> + return 0; >>>>>>>>>> >>>>>>>>>> state = drm_atomic_state_alloc(crtc->dev); >>>>>>>>>> if (!state) >>>>>>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, >>>>>>>>>> { >>>>>>>>>> struct drm_atomic_state *state; >>>>>>>>>> struct drm_plane_state *plane_state; >>>>>>>>>> - int ret = 0; >>>>>>>>>> + uint64_t retval; >>>>>>>>>> + int ret; >>>>>>>>>> + >>>>>>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); >>>>>>>>>> + if (!ret && val == retval) >>>>>>>>>> + return 0; >>>>>>>>>> >>>>>>>>>> state = drm_atomic_state_alloc(plane->dev); >>>>>>>>>> if (!state) >>>>>>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, >>>>>>>>>> { >>>>>>>>>> struct drm_atomic_state *state; >>>>>>>>>> struct drm_connector_state *connector_state; >>>>>>>>>> - int ret = 0; >>>>>>>>>> + uint64_t retval; >>>>>>>>>> + int ret; >>>>>>>>>> + >>>>>>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); >>>>>>>>>> + if (!ret && val == retval) >>>>>>>>>> + return 0; >>>>>>>>>> >>>>>>>>>> state = drm_atomic_state_alloc(connector->dev); >>>>>>>>>> if (!state) >>>>>>>>> The reason I didn't do this is that a prop change might still result in no >>>>>>>>> hw state change (e.g. if you go automitic->explicit setting matching >>>>>>>>> automatic one). Hence I think we need to solve this in lower levels >>>>>>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble >>>>>>>>> yet. >>>>>>>> Is that a ack or nack? >>>>>>> I think we shouldn't need this really for i915, and it might cover up >>>>>>> bugs. I prefer we just do the evade modeset logic you've implemented once >>>>>>> we switch over to atomic props. Since atm we only have atomic props which >>>>>>> get updated in pageflips we shouldn't have serious problems here yet (for >>>>>>> setting the rotation prop to 0° again when fbdev starts up). >>>>>>> >>>>>>> Or do I miss something still here? >>>>>> Yes, if the hardware mode is incompatible with its calculated sw mode, >>>>>> and we set a different mode from fbdev you get 2 modesets instead of 1. >>>>> How does that happen? For setting the rotation property we should just >>>>> duplicate the current crtc state. Since there's no mode changing (they >>>>> should match perfectly no matter how botched the reconstruction is) there >>>>> shouldn't be any need to recompute the config completely and discover that >>>>> there's a mismatch. Which means we'll just do the plane update (which >>>>> might do a few silly mmios but shouldn't block) and that's it. >>>>> >>>>> At least that's what I'd expect - where does this fall apart? >>>> If crtc is active and primary fb visible, and converted to atomic: >>>> >>>> restore_fbdev_mode() -> >>>> drm_mode_plane_set_obj_prop() -> >>>> drm_atomic_helper_plane_set_property() -> >>>> drm_atomic_get_plane_state() -> >>>> drm_atomic_get_crtc_state() >>>> crtc state is part of the state, intel_modeset_pipe_config performs >>>> the initial check if modeset's needed. Lets assume yes: >>> "Let's assume yes" -> that's imo a bug, so where does this happen so that >>> we can fix it? Disabling a plane or setting a plane prop really shouldn't >>> result in a modeset. Well at least if it's not a plane prop that does >>> required a modeset (but I don't think we have any of those). >> From a driver point of view you wouldn't be able to distinguish it from a real modeset to the same mode. :( >> In both cases you have all planes added and the crtc. >> >> Thinking about it more there will be 1 thing saving us from a modeset, >> drm_atomic_crtc_check will reject enable without mode_blob for atomic drivers, >> so until the first mode is set all atomic updates to the crtc will be rejected. >> >> Unfortunately you will still get WARN_ON's for this, so a better solution's needed. > Ok I think I start to grasp what's wrong, the trouble is that we don't > have the mode stuff fully set up yet (which is part of fastboot), which > means we'll get a bogus crtc_state->mode_changed despite that nothing > really changed. Ugly. No, mode_changed would be harmless, with proper skip modeset support it can be converted to a noop. > Could we insert a dummy mode_blob to avoid the WARNs and the bogus > mode_changed instead? The problem really is that doing this here is just > plugging the one source of troubles you're seeing right now (fbcon), the > initial set_* calls could come from anything really in any order. So we > really better be able to cope. Doesn't this mean we should set a real mode read out from hw state instead? > Even converting fbdev to have an optional atomic patch for DRIVER_ATOMIC > (unsafe i915 options aren't a concern here for me) won't fix this.
On Mon, Jul 13, 2015 at 11:49:01AM +0200, Maarten Lankhorst wrote: > Op 13-07-15 om 11:45 schreef Daniel Vetter: > > On Mon, Jul 13, 2015 at 11:23:45AM +0200, Maarten Lankhorst wrote: > >> Op 13-07-15 om 11:13 schreef Daniel Vetter: > >>> On Mon, Jul 13, 2015 at 10:59:32AM +0200, Maarten Lankhorst wrote: > >>>> Op 08-07-15 om 22:12 schreef Daniel Vetter: > >>>>> On Wed, Jul 08, 2015 at 08:25:07PM +0200, Maarten Lankhorst wrote: > >>>>>> Op 08-07-15 om 19:52 schreef Daniel Vetter: > >>>>>>> On Wed, Jul 08, 2015 at 06:35:47PM +0200, Maarten Lankhorst wrote: > >>>>>>>> Op 08-07-15 om 10:55 schreef Daniel Vetter: > >>>>>>>>> On Wed, Jul 08, 2015 at 10:00:22AM +0200, Maarten Lankhorst wrote: > >>>>>>>>>> Op 07-07-15 om 18:43 schreef Daniel Vetter: > >>>>>>>>>>> On Tue, Jul 07, 2015 at 05:08:34PM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>> Op 07-07-15 om 14:10 schreef Daniel Vetter: > >>>>>>>>>>>>> On Tue, Jul 07, 2015 at 12:20:10PM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>>>> Op 07-07-15 om 11:18 schreef Daniel Vetter: > >>>>>>>>>>>>>>> On Tue, Jul 07, 2015 at 09:08:13AM +0200, Maarten Lankhorst wrote: > >>>>>>>>>>>>>>>> This allows the first atomic call during hw init to be a real modeset, > >>>>>>>>>>>>>>>> which is useful for forcing a recalculation. > >>>>>>>>>>>>>>> fbcon is optional, you can't rely on anything being done in any specific > >>>>>>>>>>>>>>> way. What exactly do you need this for, what's the implications? > >>>>>>>>>>>>>> In the hw readout I noticed some warnings when I wasn't setting any mode property in the readout. > >>>>>>>>>>>>>> I want the first function to be the modeset, so we have a sane base to commit changes on. > >>>>>>>>>>>>>> Ideally this whole function would have a atomic counterpart which does it in one go. :) > >>>>>>>>>>>>> Yeah. Otoh as soon as we have atomic modeset working we can replace all > >>>>>>>>>>>>> the legacy entry points with atomic helpers, and then even plane_disable > >>>>>>>>>>>>> will be a full atomic modeset. > >>>>>>>>>>>>> > >>>>>>>>>>>>> What did fall apart with just touching properties/planes now? > >>>>>>>>>>>> Also when i915 is fully atomic it calculates in intel_modeset_compute_config > >>>>>>>>>>>> if a modeset is needed after the first atomic call. Right now because > >>>>>>>>>>>> intel_modeset_compute_config is only called in set_config so this works as expected. > >>>>>>>>>>>> Otherwise drm_plane_force_disable or rotate_0 will force a modeset, > >>>>>>>>>>>> and if the final mode is different this will introduce a double modeset. > >>>>>>>>>>> For expensive properties (i.e. a no-op changes causes something that takes > >>>>>>>>>>> time like modeset or vblank wait) we need to make sure we filter them out > >>>>>>>>>>> in atomic_check. Yeah not quite there yet with pure atomic, but meanwhile > >>>>>>>>>>> the existing legacy set_prop functions should all filter out no-op changes > >>>>>>>>>>> themselves. If we don't do that for rotation then that's a bug. > >>>>>>>>>>> > >>>>>>>>>>> Same for disabling planes harder, that shouldn't take time. Especially > >>>>>>>>>>> since fbcon only force-disable non-primary plane, and for driver load > >>>>>>>>>>> that's the exact thing we already do in the driver anyway. > >>>>>>>>>> Something like this? > >>>>>>>>>> --- > >>>>>>>>>> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>>>> index a1d4e13f3908..2989232f4996 100644 > >>>>>>>>>> --- a/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>>>> +++ b/drivers/gpu/drm/drm_atomic_helper.c > >>>>>>>>>> @@ -30,6 +30,7 @@ > >>>>>>>>>> #include <drm/drm_plane_helper.h> > >>>>>>>>>> #include <drm/drm_crtc_helper.h> > >>>>>>>>>> #include <drm/drm_atomic_helper.h> > >>>>>>>>>> +#include "drm_crtc_internal.h" > >>>>>>>>>> #include <linux/fence.h> > >>>>>>>>>> > >>>>>>>>>> /** > >>>>>>>>>> @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, > >>>>>>>>>> { > >>>>>>>>>> struct drm_atomic_state *state; > >>>>>>>>>> struct drm_crtc_state *crtc_state; > >>>>>>>>>> - int ret = 0; > >>>>>>>>>> + uint64_t retval; > >>>>>>>>>> + int ret; > >>>>>>>>>> + > >>>>>>>>>> + ret = drm_atomic_get_property(&crtc->base, property, &retval); > >>>>>>>>>> + if (!ret && val == retval) > >>>>>>>>>> + return 0; > >>>>>>>>>> > >>>>>>>>>> state = drm_atomic_state_alloc(crtc->dev); > >>>>>>>>>> if (!state) > >>>>>>>>>> @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, > >>>>>>>>>> { > >>>>>>>>>> struct drm_atomic_state *state; > >>>>>>>>>> struct drm_plane_state *plane_state; > >>>>>>>>>> - int ret = 0; > >>>>>>>>>> + uint64_t retval; > >>>>>>>>>> + int ret; > >>>>>>>>>> + > >>>>>>>>>> + ret = drm_atomic_get_property(&plane->base, property, &retval); > >>>>>>>>>> + if (!ret && val == retval) > >>>>>>>>>> + return 0; > >>>>>>>>>> > >>>>>>>>>> state = drm_atomic_state_alloc(plane->dev); > >>>>>>>>>> if (!state) > >>>>>>>>>> @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, > >>>>>>>>>> { > >>>>>>>>>> struct drm_atomic_state *state; > >>>>>>>>>> struct drm_connector_state *connector_state; > >>>>>>>>>> - int ret = 0; > >>>>>>>>>> + uint64_t retval; > >>>>>>>>>> + int ret; > >>>>>>>>>> + > >>>>>>>>>> + ret = drm_atomic_get_property(&connector->base, property, &retval); > >>>>>>>>>> + if (!ret && val == retval) > >>>>>>>>>> + return 0; > >>>>>>>>>> > >>>>>>>>>> state = drm_atomic_state_alloc(connector->dev); > >>>>>>>>>> if (!state) > >>>>>>>>> The reason I didn't do this is that a prop change might still result in no > >>>>>>>>> hw state change (e.g. if you go automitic->explicit setting matching > >>>>>>>>> automatic one). Hence I think we need to solve this in lower levels > >>>>>>>>> anyway, i.e. in when computing the config. But it shouldn't cause trouble > >>>>>>>>> yet. > >>>>>>>> Is that a ack or nack? > >>>>>>> I think we shouldn't need this really for i915, and it might cover up > >>>>>>> bugs. I prefer we just do the evade modeset logic you've implemented once > >>>>>>> we switch over to atomic props. Since atm we only have atomic props which > >>>>>>> get updated in pageflips we shouldn't have serious problems here yet (for > >>>>>>> setting the rotation prop to 0° again when fbdev starts up). > >>>>>>> > >>>>>>> Or do I miss something still here? > >>>>>> Yes, if the hardware mode is incompatible with its calculated sw mode, > >>>>>> and we set a different mode from fbdev you get 2 modesets instead of 1. > >>>>> How does that happen? For setting the rotation property we should just > >>>>> duplicate the current crtc state. Since there's no mode changing (they > >>>>> should match perfectly no matter how botched the reconstruction is) there > >>>>> shouldn't be any need to recompute the config completely and discover that > >>>>> there's a mismatch. Which means we'll just do the plane update (which > >>>>> might do a few silly mmios but shouldn't block) and that's it. > >>>>> > >>>>> At least that's what I'd expect - where does this fall apart? > >>>> If crtc is active and primary fb visible, and converted to atomic: > >>>> > >>>> restore_fbdev_mode() -> > >>>> drm_mode_plane_set_obj_prop() -> > >>>> drm_atomic_helper_plane_set_property() -> > >>>> drm_atomic_get_plane_state() -> > >>>> drm_atomic_get_crtc_state() > >>>> crtc state is part of the state, intel_modeset_pipe_config performs > >>>> the initial check if modeset's needed. Lets assume yes: > >>> "Let's assume yes" -> that's imo a bug, so where does this happen so that > >>> we can fix it? Disabling a plane or setting a plane prop really shouldn't > >>> result in a modeset. Well at least if it's not a plane prop that does > >>> required a modeset (but I don't think we have any of those). > >> From a driver point of view you wouldn't be able to distinguish it from a real modeset to the same mode. :( > >> In both cases you have all planes added and the crtc. > >> > >> Thinking about it more there will be 1 thing saving us from a modeset, > >> drm_atomic_crtc_check will reject enable without mode_blob for atomic drivers, > >> so until the first mode is set all atomic updates to the crtc will be rejected. > >> > >> Unfortunately you will still get WARN_ON's for this, so a better solution's needed. > > Ok I think I start to grasp what's wrong, the trouble is that we don't > > have the mode stuff fully set up yet (which is part of fastboot), which > > means we'll get a bogus crtc_state->mode_changed despite that nothing > > really changed. Ugly. > No, mode_changed would be harmless, with proper skip modeset support it can be converted to a noop. > > Could we insert a dummy mode_blob to avoid the WARNs and the bogus > > mode_changed instead? The problem really is that doing this here is just > > plugging the one source of troubles you're seeing right now (fbcon), the > > initial set_* calls could come from anything really in any order. So we > > really better be able to cope. > Doesn't this mean we should set a real mode read out from hw state instead? Yeah I guess so. We simply need to make sure that we have a mismatch. Your DRIVER_MODE approach seems like it should work out. -Daniel
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index a1d4e13f3908..2989232f4996 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -30,6 +30,7 @@ #include <drm/drm_plane_helper.h> #include <drm/drm_crtc_helper.h> #include <drm/drm_atomic_helper.h> +#include "drm_crtc_internal.h" #include <linux/fence.h> /** @@ -1716,7 +1717,12 @@ drm_atomic_helper_crtc_set_property(struct drm_crtc *crtc, { struct drm_atomic_state *state; struct drm_crtc_state *crtc_state; - int ret = 0; + uint64_t retval; + int ret; + + ret = drm_atomic_get_property(&crtc->base, property, &retval); + if (!ret && val == retval) + return 0; state = drm_atomic_state_alloc(crtc->dev); if (!state) @@ -1776,7 +1782,12 @@ drm_atomic_helper_plane_set_property(struct drm_plane *plane, { struct drm_atomic_state *state; struct drm_plane_state *plane_state; - int ret = 0; + uint64_t retval; + int ret; + + ret = drm_atomic_get_property(&plane->base, property, &retval); + if (!ret && val == retval) + return 0; state = drm_atomic_state_alloc(plane->dev); if (!state) @@ -1836,7 +1847,12 @@ drm_atomic_helper_connector_set_property(struct drm_connector *connector, { struct drm_atomic_state *state; struct drm_connector_state *connector_state; - int ret = 0; + uint64_t retval; + int ret; + + ret = drm_atomic_get_property(&connector->base, property, &retval); + if (!ret && val == retval) + return 0; state = drm_atomic_state_alloc(connector->dev); if (!state) diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c index 424c83323aaa..5bab7bff8a15 100644 --- a/drivers/gpu/drm/drm_crtc.c +++ b/drivers/gpu/drm/drm_crtc.c @@ -1327,7 +1327,8 @@ void drm_plane_force_disable(struct drm_plane *plane) { int ret; - if (!plane->fb) + if ((plane->state && !plane->state->fb) || + (!plane->state && !plane->fb)) return; plane->old_fb = plane->fb;