[PATCH] modesetting: Support native primary plane rotation

[Chris Wilson]

On Wed, Jul 09, 2014 at 12:57:12PM +0300, Pekka Paalanen wrote:
> On Wed,  9 Jul 2014 09:19:08 +0100
> Chris Wilson <chris at chris-wilson.co.uk> wrote:
> 
> > With the advent of universal drm planes and the introduction of generic
> > plane properties for rotations, we can query and program the hardware
> > for native rotation support.
> > 
> > NOTE: this depends upon the next release of libdrm to remove one
> > opencoded define.
> > 
> > v2: Use enum to determine primary plane, suggested by Pekka Paalanen.
> >     Use libobj for replacement ffs(), suggested by walter harms
> > 
> > Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Pekka Paalanen <ppaalanen at gmail.com>
> > Cc: walter harms <wharms at bfs.de>
> 
> My concerns have been addressed. On a second read, I found another
> suspicious thing below.
> 
> > +				if (strcmp(prop->name, "rotation") == 0) {
> > +					drmmode_crtc->rotation_prop_id = proplist->props[j];
> > +					drmmode_crtc->current_rotation = proplist->prop_values[j];
> > +					for (k = 0; k < prop->count_enums; k++) {
> > +						int rr = -1;
> > +						if (strcmp(prop->enums[k].name, "rotate-0") == 0)
> > +							rr = RR_Rotate_0;
> > +						else if (strcmp(prop->enums[k].name, "rotate-90") == 0)
> > +							rr = RR_Rotate_90;
> > +						else if (strcmp(prop->enums[k].name, "rotate-180") == 0)
> > +							rr = RR_Rotate_180;
> > +						else if (strcmp(prop->enums[k].name, "rotate-270") == 0)
> > +							rr = RR_Rotate_270;
> > +						else if (strcmp(prop->enums[k].name, "reflect-x") == 0)
> > +							rr = RR_Reflect_X;
> > +						else if (strcmp(prop->enums[k].name, "reflect-y") == 0)
> > +							rr = RR_Reflect_Y;
> > +						if (rr != -1) {
> > +							drmmode_crtc->map_rotations[rotation_index(rr)] = 1 << prop->enums[k].value;
> > +							drmmode_crtc->supported_rotations |= rr;
> 
> Comparing the above assignments to...
> 
> > +static Bool
> > +rotation_set(xf86CrtcPtr crtc, unsigned rotation)
> > +{
> > +	drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
> > +	drmmode_ptr drmmode = drmmode_crtc->drmmode;
> > +
> > +	if (drmmode_crtc->current_rotation == rotation)
> > +		return TRUE;
> > +
> > +	if ((drmmode_crtc->supported_rotations & rotation) == 0)
> > +		return FALSE;
> > +
> > +	if (drmModeObjectSetProperty(drmmode->fd,
> > +				     drmmode_crtc->primary_plane_id,
> > +				     DRM_MODE_OBJECT_PLANE,
> > +				     drmmode_crtc->rotation_prop_id,
> > +				     drmmode_crtc->map_rotations[rotation_index(rotation)]))
> 
> ...the use here, it does not look like you are passing
> prop->enums[k].value here. It is like you are missing ffs() here or
> having a 1<< too much in the assignment.

It doesn't take the enum.value but 1 << enum.value.
 
> Btw. would it be possible to do e.g. rotate-90 with reflect?

Indeed. That's an issue from only using the first index...
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre