On 11.12.2018 00:45, Inki Dae wrote: > Hi Andrzej, > > 18. 12. 10. 오후 4:35에 Andrzej Hajda 이(가) 쓴 글: >> Hi Inki, >> >> On 10.12.2018 03:25, Inki Dae wrote: >>> Hi Andrzej, >>> >>> 18. 12. 6. 오후 6:38에 Andrzej Hajda 이(가) 쓴 글: >>>> Hi Inki, >>>> >>>> This small patchset adds dynamic zpos support for DECON and FIMD. >>> This patch will allow user space to change zpos. However, DECON and FIMD >>> devices have fixed priority of HW overlays. >>> This would mean that zpos change by user space doesn't guarantee correct HW >>> overlay priority. >>> >>> Why do you want to support mutable zpos? >> >> Practically you have patches which proves it works, you can see that >> changing zpos value results in adequate change in displayed image. >> >> Conceptually it is just a matter of disconnecting hardware windows >> present in DECON and FIMD from DRM planes which are software entities. >> >> You can reason about it this way: >> >> - drm plane is a framebuffer plus informations how it should be >> transformed/displayed on DECON/FIMD, >> >> - hw window in DECON/FIMD is just a channel through which plane is send >> to the display. >> >> DECON and FIMD has fixed hw windows order - windows with lower numbers >> are displayed below windows with higher number. To display planes in >> given z-order you just need to send them via windows with appropriate >> index - farthest plane should go always via win0, closer one via win1, >> ..., till the last plane. >> >> So for example if you have three planes and want to display them in >> following order (first one farthest, last one closest): >> >> plane2, plane1, plane3 >> >> you should map them to planes as follow: >> >> plane2 -> win0, plane1 -> win1, plane3 -> win2 >> >> then for example plane2 is disabled, we will have following mapping: >> >> plane1 -> win0, plane3 -> win1, win2 - disabled > Plane1 is displayed below Plane3.
And this is what we wanted, the initial order was: plane2, plane1, plane3, first farthest (or lowest if you prefer this naming schema). > >> then if you change zorder of planes to: plane3, plane1: >> >> plane3 -> win0, plane1 -> win1 > Plane3 is displayed below Plane1 because DECON/FIMD HW aren't able to change > HW overlay priroty. No, plane3 is displayed below plane1 because we sent it via win0, if we want inverse we can send plane3 via win1 and plane1 via win0. > However, user space wanted that Plane1 is displayed below Plane3. Like this, > zpos change by user space doesn't guarantee correct HW overlay priority. As I said before in this example userspace wanted plane3 below plane1, and as I wrote in comment above any order of planes user want driver is able to realize with this patch. > And there is no any reason to change zpos in user space excepting Mixer > device which supports HW overlay priority change. Lack of special registry for manipulating windows order does not mean it cannot support dynamic zpos. > In fact, we supported mutable zpos before but changed it to immutable with > same reason. It was just broken if I remember correctly. > > Lastly, your patch made real user broken. Who? How? Regards Andrzej > > Thanks, > Inki Dae > >> >> As you see there is no relation between plane number and window number, >> but window number is equal to plane's position in zpos-ordered list of >> planes and this is exact value of normalized_zpos field in drm_plane_state. >> >> >> I hope this extended explanation will clarify things. >> >> >> Regards >> >> Andrzej >> >> >> >>> Thanks, >>> Inki Dae >>> >>>> It was tested on tm2 and trats2. >>>> >>>> Regards >>>> Andrzej >>>> >>>> >>>> Andrzej Hajda (3): >>>> drm/exynos/decon5433: add dynamic zpos support >>>> drm/exynos/fimd: create local helper for disabling hardware window >>>> drm/exynos/fimd: add dynamic zpos support >>>> >>>> drivers/gpu/drm/exynos/exynos5433_drm_decon.c | 23 +++++----- >>>> drivers/gpu/drm/exynos/exynos_drm_fimd.c | 42 ++++++++----------- >>>> 2 files changed, 29 insertions(+), 36 deletions(-) >>>> >> >> > _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel
