[PATCH weston] compositor-drm: disable hardware cursors

[Pekka Paalanen]

On Tue, 19 May 2015 10:17:49 +0200
Hardening <rdp.effort at gmail.com> wrote:

> Le 19/05/2015 09:26, Pekka Paalanen a écrit :
> > From: Pekka Paalanen <pekka.paalanen at collabora.co.uk>
> > 

> >  src/compositor-drm.c | 12 ++++++++++--
> >  1 file changed, 10 insertions(+), 2 deletions(-)
> > 
> > diff --git a/src/compositor-drm.c b/src/compositor-drm.c
> > index 313860b..0a9af5d 100644
> > --- a/src/compositor-drm.c
> > +++ b/src/compositor-drm.c
> > @@ -2817,9 +2817,17 @@ drm_compositor_create(struct wl_display *display,
> >  	if (ec == NULL)
> >  		return NULL;
> >  
> > -	/* KMS support for sprites is not complete yet, so disable the
> > -	 * functionality for now. */
> > +	/*
> > +	 * KMS support for hardware planes cannot properly synchronize
> > +	 * without nuclear page flip. Without nuclear/atomic, hw plane
> > +	 * and cursor plane updates would either tear or cause extra
> > +	 * waits for vblanks which means dropping the compositor framerate
> > +	 * to a fraction.
> > +	 *
> > +	 * These can be enabled again when nuclear/atomic support lands.
> > +	 */
> >  	ec->sprites_are_broken = 1;
> > +	ec->cursors_are_broken = 1;
> >  
> >  	section = weston_config_get_section(config, "core", NULL, NULL);
> >  	if (get_gbm_format_from_section(section,
> > 
> Perhaps it would be nice if the most adventurous of us could re-enable
> the cursors using a configuration file option...

Oh but you can, I believe. Except it's not a config option, it is a
debug key binding.

Debug key 'c' toggles hw cursors.
Debug key 'v' toggles hw overlays (sprites).
Debug key 'o' causes hw overlays to not be shown if they are used, so
you can see what's behind them while the compositor still thinks they
are there.

We should probably document those, but in the mean time
	$ git grep -A1 add_debug_binding
will find all debug key bindings.

> Except this non blocking remark,
> Reviewed-By: David FORT <contact at hardening-consulting.com>

Thanks,
pq