On Wed, 2015-08-26 at 18:53 +0300, Ville Syrjälä wrote:
On Wed, Aug 26, 2015 at 05:41:23PM +0200, Daniel Vetter wrote:
Very strictly speaking this is possible if you have special hw and genlocked CRTCs. In general switching a plane between two active CRTC just won't work so well and is probably not tested at all. Just forbid it.
I've put this into the core since I really couldn't come up with a case where we don't want to enforce that. But if that ever happens it would be easy to move this check into helpers.
v2: don't bother with complexity and just outright disallow plane switching without the intermediate OFF state. Simplifies drivers, we don't have any hw that could do it anyway and current atomic userspace (weston) works like this already anyway.
Cc: Thierry Reding thierry.reding@gmail.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Daniel Stone daniels@collabora.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com
drivers/gpu/drm/drm_atomic.c | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+)
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 434915448ea0..f27aae3fa765 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -663,6 +663,22 @@ drm_atomic_plane_get_property(struct drm_plane *plane, return 0; }
+static bool +plane_switching(struct drm_atomic_state *state,
struct drm_plane *plane,struct drm_plane_state *plane_state)plane_switching_crtc()?
With Ville's shed colour: Acked-by: Daniel Stone daniels@collabora.com
As this won't work in the general case, I'd prefer to see a hint to userspace that two CRTCs are genlocked before we enable it and people start to rely on it.
Cheers, Daniel