[PATCH v3 0/3] drm/vkms: Add support for multiple pipes

[Brandon Ross Pollack]

I'm adding the original offer of those changes.  We talked recently
and they have the intent to push forward and merge them.  I'm still
getting up to speed a bit, but I will probably have a stronger opinion
by early next week.


On Wed, Apr 26, 2023 at 9:54 PM Marius Vlad <marius.vlad at collabora.com> wrote:
>
> Hi Brandon, Xie,
>
> Thanks for reaching out, and for the heads-up. I need to take a closer
> look, but by glancing over it, using configFS would be really awesome.
> Think we could really benefit from having that in our CI and being able
> to customize the entire pipeline. I'm totally for that.
>
> It looks like it requires some infra work so I guess landing that might
> require quite a bit of time. Not sure if there are recent updates for it.
>
> My changes are quite trivial and much more focused on just having
> multiple virtual displays, so IDK, I've submitted a version that seems
> to work, so I guess others should or would decide if we should drop mine
> and focus on the configFS series, or we should go with configFS as a
> follow-up. Would have liked to get something in the tree so we can at
> least have something to work with.
>
> Thoughts on the matter on how should we go about it?
>
> On 4/26/23 05:06, Brandon Ross Pollack wrote:
> > We're doing/planning on doing similar or related work here at chromium.
> >
> > https://patchwork.kernel.org/project/dri-devel/list/?series=662676&submitter=&state=&q=&delegate=&archive=both <https://patchwork.kernel.org/project/dri-devel/list/?series=662676&submitter=&state=&q=&delegate=&archive=both>
> >
> > Here's the stuff we have now (we're currently rebasing and touching it
> > up, myself and @Yi Xie <mailto:yixie at google.com> will be taking over
> > this work.
> >
> > Our plans are to add configFS changes and DRI VKMS changes to be able to
> > add and remove virtual displays at runtime (among other things needed
> > for our own testing purposes for our Exo wayland implementation).
> >
> > We're still learning how this all works and comes together, but it is
> > worth letting you know "us too"
> >
> > We can chat more and see where we overlap and can learn from each other :)
> >
> > On Tue, Apr 25, 2023 at 4:30 PM Marius Vlad <marius.vlad at collabora.com
> > <mailto:marius.vlad at collabora.com>> wrote:
> >
> >     With multiple pipe available we can perform management of outputs at
> >     a more granular level, such that we're able to turn off or on several
> >     outputs at a time, or combinations that arise from doing that.
> >
> >     The Weston project use VKMS when running its test suite in CI, and we
> >     have now uses cases which would need to ability to set-up the outputs
> >     DPMS/state individually, rather than globally -- which would affect all
> >     outputs. This an attempt on fixing that by giving the possibility to
> >     create more than one pipe, and thus allowing to run tests that could
> >     exercise code paths in the compositor related to management of outputs.
> >
> >     v3:
> >        - Apply the series against drm-misc-next (Maíra Canal)
> >        - Add a lower range check to avoid passing negative values to
> >        max_pipes (Maíra Canal)
> >
> >     v2:
> >        - Replace 'outputs' with 'pipes' as to use the proper terminology
> >          (Thomas Zimmermann, Maíra Canal)
> >        - Fixed passing wrong possible_crtc bitmask when initializing the
> >          write back connector which address kms_writeback failure (Maíra
> >     Canal)
> >        - Add a feat. note about moving overlay planes between CRTCs
> >     (Melissa Wen)
> >
> >     Marius Vlad (3):
> >        vkms: Pass the correct bitmask for possible crtcs
> >        vkms: Add support for multiple pipes
> >        Documentation/gpu/vkms.rst: Added a note about plane migration
> >
> >       Documentation/gpu/vkms.rst            |  5 +++--
> >       drivers/gpu/drm/vkms/vkms_crtc.c      |  3 +--
> >       drivers/gpu/drm/vkms/vkms_drv.c       | 31 +++++++++++++++++++++------
> >       drivers/gpu/drm/vkms/vkms_drv.h       | 12 ++++++++---
> >       drivers/gpu/drm/vkms/vkms_output.c    |  7 +++---
> >       drivers/gpu/drm/vkms/vkms_writeback.c | 24 ++++++++++-----------
> >       6 files changed, 53 insertions(+), 29 deletions(-)
> >
> >     --
> >     2.39.2
> >