Commit f32fb675 authored by Ville Syrjälä's avatar Ville Syrjälä Committed by Peng Zhang
Browse files

drm/i915: Fix intel_atomic_setup_scalers() plane_state handling 

stable inclusion
from stable-v6.6.8
commit a9d951b007904942e2519bc8ff7ba2d1b4121060
bugzilla: https://gitee.com/openeuler/kernel/issues/I99K53

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a9d951b007904942e2519bc8ff7ba2d1b4121060



--------------------------------

commit c3070f080f9ba18dea92eaa21730f7ab85b5c8f4 upstream.

Since the plane_state variable is declared outside the scaler_users
loop in intel_atomic_setup_scalers(), and it's never reset back to
NULL inside the loop we may end up calling intel_atomic_setup_scaler()
with a non-NULL plane state for the pipe scaling case. That is bad
because intel_atomic_setup_scaler() determines whether we are doing
plane scaling or pipe scaling based on plane_state!=NULL. The end
result is that we may miscalculate the scaler mode for pipe scaling.

The hardware becomes somewhat upset if we end up in this situation
when scanning out a planar format on a SDR plane. We end up
programming the pipe scaler into planar mode as well, and the
result is a screenfull of garbage.

Fix the situation by making sure we pass the correct plane_state==NULL
when calculating the scaler mode for pipe scaling.

Cc: stable@vger.kernel.org
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231207193441.20206-2-ville.syrjala@linux.intel.com


Reviewed-by: default avatarJani Nikula <jani.nikula@intel.com>
(cherry picked from commit e81144106e21271c619f0c722a09e27ccb8c043d)
Signed-off-by: default avatarJani Nikula <jani.nikula@intel.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarZhangPeng <zhangpeng362@huawei.com>
parent c8a68b95

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

+1 −1
Original line number Diff line number Diff line
@@ -504,7 +504,6 @@ int intel_atomic_setup_scalers(struct drm_i915_private *dev_priv, 
{

	struct drm_plane *plane = NULL;

	struct intel_plane *intel_plane;

	struct intel_plane_state *plane_state = NULL;

	struct intel_crtc_scaler_state *scaler_state =

		&crtc_state->scaler_state;

	struct drm_atomic_state *drm_state = crtc_state->uapi.state;
@@ -536,6 +535,7 @@ int intel_atomic_setup_scalers(struct drm_i915_private *dev_priv, 


	/* walkthrough scaler_users bits and start assigning scalers */

	for (i = 0; i < sizeof(scaler_state->scaler_users) * 8; i++) {

		struct intel_plane_state *plane_state = NULL;

		int *scaler_id;

		const char *name;

		int idx, ret;