On Tue, 25 Oct 2011 13:58:55 +0200 Daniel Vetter daniel@ffwll.ch wrote:
On Tue, Oct 25, 2011 at 11:46:56AM +0200, Jesse Barnes wrote:
Planes are a bit like half-CRTCs. They have a location and fb, but don't drive outputs directly. Add support for handling them to the core KMS code.
Signed-off-by: Jesse Barnes jbarnes@virtuousgeek.org
As discussed with Jesse on irc, drm fb handling is fragile. Current rules:
- fbs are not reference counted, hence when destroying we need to
disable all crtcs (and now also planes) that use them. drm_framebuffer_cleanup does that atm
- drivers that hold onto fbs after the kms core drops the
corresponding pointer needs to hold a ref onto the underlying backing storage (like e.g. for pageflip on the to-be-flipped-out fb as long as it might still be scanned out).
We need proper refcounting for these ... But for now this patch is missing the plane cleanup in drm_framebuffer_cleanup.
Ah yeah that's a better place for the disable plane call I currently have in the intel specific code... I'll fix up and test.
Otherwise I think going with just the src and dst rect for set_plane is about the only sensible thing given the crazy hw out there. But I lack the knowledge about that kind of hw (and video stuff in general), so I'll refrain from slapping my r-b on these two.
Yeah, I think the drivers just need to be able to calculate the scaling level from the params and program them into whatever regs they happen to have (on Intel fortunately the scaling is figured out by hw when we program in the source & dest values, subject to some restrictions).
Thanks, Jesse