On Mon, Apr 08, 2019 at 03:40:39PM +0000, Shankar, Uma wrote: > > > >-----Original Message----- > >From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxxxxxxxx] > >Sent: Monday, April 8, 2019 8:27 PM > >To: Shankar, Uma <uma.shankar@xxxxxxxxx> > >Cc: dcastagna@xxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; dri- > >devel@xxxxxxxxxxxxxxxxxxxxx; seanpaul@xxxxxxxxxxxx; Syrjala, Ville > ><ville.syrjala@xxxxxxxxx>; Lankhorst, Maarten <maarten.lankhorst@xxxxxxxxx> > >Subject: Re: [v2 0/7] Add Multi Segment Gamma Support > > > >On Mon, Apr 08, 2019 at 02:40:51PM +0000, Shankar, Uma wrote: > >> > >> > >> >-----Original Message----- > >> >From: Ville Syrjälä [mailto:ville.syrjala@xxxxxxxxxxxxxxx] > >> >Sent: Monday, April 8, 2019 6:01 PM > >> >To: Shankar, Uma <uma.shankar@xxxxxxxxx> > >> >Cc: dcastagna@xxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; dri- > >> >devel@xxxxxxxxxxxxxxxxxxxxx; seanpaul@xxxxxxxxxxxx; Syrjala, Ville > >> ><ville.syrjala@xxxxxxxxx>; Lankhorst, Maarten > >> ><maarten.lankhorst@xxxxxxxxx> > >> >Subject: Re: [v2 0/7] Add Multi Segment Gamma Support > >> > > >> >On Mon, Apr 08, 2019 at 12:26:23PM +0000, Shankar, Uma wrote: > >> >> > >> >> > >> >> >-----Original Message----- > >> >> >From: dri-devel [mailto:dri-devel-bounces@xxxxxxxxxxxxxxxxxxxxx] > >> >> >On Behalf Of Ville Syrjälä > >> >> >Sent: Friday, April 5, 2019 9:42 PM > >> >> >To: Shankar, Uma <uma.shankar@xxxxxxxxx> > >> >> >Cc: dcastagna@xxxxxxxxxxxx; intel-gfx@xxxxxxxxxxxxxxxxxxxxx; dri- > >> >> >devel@xxxxxxxxxxxxxxxxxxxxx; seanpaul@xxxxxxxxxxxx; Syrjala, Ville > >> >> ><ville.syrjala@xxxxxxxxx>; Lankhorst, Maarten > >> >> ><maarten.lankhorst@xxxxxxxxx> > >> >> >Subject: Re: [v2 0/7] Add Multi Segment Gamma Support > >> >> > > >> >> >On Mon, Apr 01, 2019 at 11:00:04PM +0530, Uma Shankar wrote: > >> >> >> This series adds support for programmable gamma modes and > >> >> >> exposes a property interface for the same. Also added, support > >> >> >> for multi segment gamma mode introduced in ICL+ > >> >> >> > >> >> >> It creates 2 property interfaces : > >> >> >> 1. GAMMA_MODE_CAPS: This is immutable property and exposes the > >> >> >> various gamma modes supported and the lut ranges. This is an > >> >> >> enum property with element as blob id. Getting the blob id in > >> >> >> userspace, user can get the mode supported and also the range of > >> >> >> gamma mode supported with number of lut coefficients. > >> >> >> > >> >> >> 2. GAMMA_MODE: This is for user to set the gamma mode and send > >> >> >> the lut values for that particular mode. > >> >> > > >> >> >I think we should just go for the BLOB_ENUM prop type instead. > >> >> >Then the possible values and the current value are all part of the same prop. > >> >> > >> >> Hi Ville, > >> >> With the current approach, we have enum property with values as > >> >> blob_ids (representing platform capabilities). This should not get > >> >> modified and needs to be immutable. > >> > > >> >That's not quite what we want. We want to let the user modify the > >> >current value so that they can actually select the gamma mode. > >> >Otherwise we need yet another prop for it, or we have to deduce it > >> >from the LUT size (that apporach would actually work for i915 but may > >> >not work for other drivers/hardware). > >> > > >> >> > >> >> Userspace can query the property and get the blob using the blob_ids. > >> >> Thereby getting all the platform capabilities. > >> >> > >> >> Now to set the LUT values, he can use another blob property and > >> >> pass the luts. This is inline to how gamma/degamma is implemented > >> >> where we have one immutable LUT_SIZE property (indicating number of > >> >> luts) and another blob property for actual lut values.. > >> > >> Hi Ville, > >> Just to clarify and clear some doubts :) > >> > >> We should be able to set the gamma mode using the blob enum value. > >> Userspace will get the list enum vals (blob ids with mode name embedded) and > >select one and do a setprop to set a mode. > >> Driver will get the blob_id and will be able to get the mode to be > >> set. So exposing capabilities and setting the mode should be possible with this one > >property. I hope my understanding is correct. > >> > >> Now to send the actual blob values to be set, we need to use some > >> other property interface. Should we use the currently available "gamma blob > >(gamma_lut_property)" property to send the lut values. > >> The challenge there is that it currently uses 16 bit lut values struct > >> drm_color_lut { > >> __u16 red; > >> __u16 green; > >> __u16 blue; > >> __u16 reserved; > >> }; > >> which is not sufficient for HDR usecases. Or should we need a new property for > >advance lut/extended lut like below: > >> https://patchwork.freedesktop.org/patch/294732/?series=30875&rev=7 > >> > >> What do you suggest ? > > > >I was thinking that we might get away with reusing the current props and just change > >the interpretation of the data when gamma_mode is set. But I'm not sure that's going > >to work out so well if one client sets this up and then another client comes along that > >doesn't understand the new props at all. But even with separate props I think we > >might still end up in a mess because the new client wouldn't know how to unset the > >higher precision LUT before setting up the old style prop and the kernel would then > >refuse the operation with with both props being set. > > > >So I think we might need a client cap for this which simply changes how the data in > >the existing props is represented. So internally we could always store things in the > >new high precision format, but we'd convert to/from the old format when dealing > >with an older client. > > We could also say that if a legacy gamma_mode_property is set (which will be used by > legacy apps or apps not aware of new interface), in driver we will simply unset the > earlier gamma_mode and fallback to legacy mode (whatever it was for a particular > platform). This way we should be able to deal with this situation and an explicit unset > may not be needed. What do you think ? I don't want (non-immutable) properties that magically change values. That way lies madness. > > >> > >> Note: I have currently used 16bit values only to get the feedback on the approach. > >> > >> Regards, > >> Uma Shankar > >> > >> >> > >> >> >> > >> >> >> v2: Used Ville's design and approach to define the interfaces. > >> >> >> Addressed Matt Roper's review feedback and re-ordered the patches. > >> >> >> > >> >> >> Uma Shankar (5): > >> >> >> drm: Add gamma mode property > >> >> >> drm/i915/icl: Add register definitions for Multi Segmented gamma > >> >> >> drm/i915/icl: Add support for multi segmented gamma mode > >> >> >> drm/i915: Add gamma mode caps property > >> >> >> drm/i915: Attach gamma mode property > >> >> >> > >> >> >> Ville Syrjälä (2): > >> >> >> drm: Add gamma mode caps property > >> >> >> drm/i915: Define color lut range structure > >> >> >> > >> >> >> drivers/gpu/drm/drm_atomic_uapi.c | 13 + > >> >> >> drivers/gpu/drm/drm_color_mgmt.c | 110 +++++++++ > >> >> >> drivers/gpu/drm/i915/i915_reg.h | 17 ++ > >> >> >> drivers/gpu/drm/i915/intel_color.c | 465 > >> >> >++++++++++++++++++++++++++++++++++- > >> >> >> drivers/gpu/drm/i915/intel_display.c | 5 + > >> >> >> include/drm/drm_color_mgmt.h | 11 + > >> >> >> include/drm/drm_crtc.h | 17 ++ > >> >> >> include/drm/drm_mode_config.h | 10 + > >> >> >> include/uapi/drm/drm_mode.h | 49 ++++ > >> >> >> 9 files changed, 690 insertions(+), 7 deletions(-) > >> >> >> > >> >> >> -- > >> >> >> 1.9.1 > >> >> >> > >> >> >> _______________________________________________ > >> >> >> Intel-gfx mailing list > >> >> >> Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > >> >> >> https://lists.freedesktop.org/mailman/listinfo/intel-gfx > >> >> > > >> >> >-- > >> >> >Ville Syrjälä > >> >> >Intel > >> >> >_______________________________________________ > >> >> >dri-devel mailing list > >> >> >dri-devel@xxxxxxxxxxxxxxxxxxxxx > >> >> >https://lists.freedesktop.org/mailman/listinfo/dri-devel > >> > > >> >-- > >> >Ville Syrjälä > >> >Intel > > > >-- > >Ville Syrjälä > >Intel -- Ville Syrjälä Intel _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
