drm/i915: Check plane configuration properly (9877c37e) · Commits · 戴 / test

Checking with hweight8 if plane configuration had changed seems to be wrong as different plane configs can result in a same hamming weight. So lets check the bitmask itself. v2: Fixed "from" field which got corrupted for some weird reason Reviewed-by:

Manasi Navare <manasi.d.navare@intel.com> Signed-off-by:

Stanislav Lisovskiy <stanislav.lisovskiy@intel.com> Signed-off-by:

Manasi Navare <manasi.d.navare@intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20200520145827.15887-1-stanislav.lisovskiy@intel.com

drivers/gpu/drm/i915/display/intel_display.c

+7 −1

Original line number	Diff line number	Diff line
		@@ -14688,7 +14688,13 @@ static int intel_atomic_check_planes(struct intel_atomic_state *state)
		old_active_planes = old_crtc_state->active_planes & ~BIT(PLANE_CURSOR);
		new_active_planes = new_crtc_state->active_planes & ~BIT(PLANE_CURSOR);

		if (hweight8(old_active_planes) == hweight8(new_active_planes))
		/*
		* Not only the number of planes, but if the plane configuration had
		* changed might already mean we need to recompute min CDCLK,
		* because different planes might consume different amount of Dbuf bandwidth
		* according to formula: Bw per plane = Pixel rate * bpp * pipe/plane scale factor
		*/
		if (old_active_planes == new_active_planes)
		continue;

		ret = intel_crtc_add_planes_to_state(state, crtc, new_active_planes);

Admin message