[PATCH] drm/mediatek: only announce AFBC if really supported

[Icenowy Zheng]

Currently even the SoC's OVL does not declare the support of AFBC, AFBC
is still announced to the userspace within the IN_FORMATS blob, which
breaks modern Wayland compositors like KWin Wayland and others.

Gate passing modifiers to drm_universal_plane_init() behind querying the
driver of the hardware block for AFBC support.

Fixes: c410fa9b07c3 ("drm/mediatek: Add AFBC support to Mediatek DRM driver")
Signed-off-by: Icenowy Zheng <uwu at icenowy.me>
---
Patch tested on MT8183, on which KWin Wayland 5.27.12 is fixed.

In addition, I tried to fake supports_afbc in mt8183_ovl_driver_data and
mt8183_ovl_2l_driver_data, then KWin Wayland gets broken again and
modetest also shows the AFBC modifier in IN_FORMATS.

 drivers/gpu/drm/mediatek/mtk_crtc.c     | 3 ++-
 drivers/gpu/drm/mediatek/mtk_ddp_comp.c | 1 +
 drivers/gpu/drm/mediatek/mtk_ddp_comp.h | 9 +++++++++
 drivers/gpu/drm/mediatek/mtk_disp_drv.h | 1 +
 drivers/gpu/drm/mediatek/mtk_disp_ovl.c | 7 +++++++
 drivers/gpu/drm/mediatek/mtk_plane.c    | 7 +++++--
 drivers/gpu/drm/mediatek/mtk_plane.h    | 3 ++-
 7 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c
index 8f6fba4217ece..53359c2465b65 100644
--- a/drivers/gpu/drm/mediatek/mtk_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_crtc.c
@@ -930,7 +930,8 @@ static int mtk_crtc_init_comp_planes(struct drm_device *drm_dev,
 				mtk_ddp_comp_supported_rotations(comp),
 				mtk_ddp_comp_get_blend_modes(comp),
 				mtk_ddp_comp_get_formats(comp),
-				mtk_ddp_comp_get_num_formats(comp), i);
+				mtk_ddp_comp_get_num_formats(comp),
+				mtk_ddp_comp_is_afbc_supported(comp), i);
 		if (ret)
 			return ret;
 
diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
index edc6417639e64..ac6620e10262e 100644
--- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
+++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.c
@@ -366,6 +366,7 @@ static const struct mtk_ddp_comp_funcs ddp_ovl = {
 	.get_blend_modes = mtk_ovl_get_blend_modes,
 	.get_formats = mtk_ovl_get_formats,
 	.get_num_formats = mtk_ovl_get_num_formats,
+	.is_afbc_supported = mtk_ovl_is_afbc_supported,
 };
 
 static const struct mtk_ddp_comp_funcs ddp_postmask = {
diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
index 39720b27f4e9e..7289b3dcf22f2 100644
--- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
+++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h
@@ -83,6 +83,7 @@ struct mtk_ddp_comp_funcs {
 	u32 (*get_blend_modes)(struct device *dev);
 	const u32 *(*get_formats)(struct device *dev);
 	size_t (*get_num_formats)(struct device *dev);
+	bool (*is_afbc_supported)(struct device *dev);
 	void (*connect)(struct device *dev, struct device *mmsys_dev, unsigned int next);
 	void (*disconnect)(struct device *dev, struct device *mmsys_dev, unsigned int next);
 	void (*add)(struct device *dev, struct mtk_mutex *mutex);
@@ -294,6 +295,14 @@ size_t mtk_ddp_comp_get_num_formats(struct mtk_ddp_comp *comp)
 	return 0;
 }
 
+static inline bool mtk_ddp_comp_is_afbc_supported(struct mtk_ddp_comp *comp)
+{
+	if (comp->funcs && comp->funcs->is_afbc_supported)
+		return comp->funcs->is_afbc_supported(comp->dev);
+
+	return false;
+}
+
 static inline bool mtk_ddp_comp_add(struct mtk_ddp_comp *comp, struct mtk_mutex *mutex)
 {
 	if (comp->funcs && comp->funcs->add) {
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_drv.h b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
index 04217a36939cd..679d413bf10be 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_drv.h
+++ b/drivers/gpu/drm/mediatek/mtk_disp_drv.h
@@ -106,6 +106,7 @@ void mtk_ovl_disable_vblank(struct device *dev);
 u32 mtk_ovl_get_blend_modes(struct device *dev);
 const u32 *mtk_ovl_get_formats(struct device *dev);
 size_t mtk_ovl_get_num_formats(struct device *dev);
+bool mtk_ovl_is_afbc_supported(struct device *dev);
 
 void mtk_ovl_adaptor_add_comp(struct device *dev, struct mtk_mutex *mutex);
 void mtk_ovl_adaptor_remove_comp(struct device *dev, struct mtk_mutex *mutex);
diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
index d0581c4e3c999..e0236353d4997 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -236,6 +236,13 @@ size_t mtk_ovl_get_num_formats(struct device *dev)
 	return ovl->data->num_formats;
 }
 
+bool mtk_ovl_is_afbc_supported(struct device *dev)
+{
+	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
+
+	return ovl->data->supports_afbc;
+}
+
 int mtk_ovl_clk_enable(struct device *dev)
 {
 	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
diff --git a/drivers/gpu/drm/mediatek/mtk_plane.c b/drivers/gpu/drm/mediatek/mtk_plane.c
index 655106bbb76d3..e08b771bc25e9 100644
--- a/drivers/gpu/drm/mediatek/mtk_plane.c
+++ b/drivers/gpu/drm/mediatek/mtk_plane.c
@@ -321,7 +321,8 @@ static const struct drm_plane_helper_funcs mtk_plane_helper_funcs = {
 int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane,
 		   unsigned long possible_crtcs, enum drm_plane_type type,
 		   unsigned int supported_rotations, const u32 blend_modes,
-		   const u32 *formats, size_t num_formats, unsigned int plane_idx)
+		   const u32 *formats, size_t num_formats,
+		   bool supports_afbc, unsigned int plane_idx)
 {
 	int err;
 
@@ -332,7 +333,9 @@ int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane,
 
 	err = drm_universal_plane_init(dev, plane, possible_crtcs,
 				       &mtk_plane_funcs, formats,
-				       num_formats, modifiers, type, NULL);
+				       num_formats,
+				       supports_afbc ? modifiers : NULL,
+				       type, NULL);
 	if (err) {
 		DRM_ERROR("failed to initialize plane\n");
 		return err;
diff --git a/drivers/gpu/drm/mediatek/mtk_plane.h b/drivers/gpu/drm/mediatek/mtk_plane.h
index 3b13b89989c7e..95c5fa5295d8a 100644
--- a/drivers/gpu/drm/mediatek/mtk_plane.h
+++ b/drivers/gpu/drm/mediatek/mtk_plane.h
@@ -49,5 +49,6 @@ to_mtk_plane_state(struct drm_plane_state *state)
 int mtk_plane_init(struct drm_device *dev, struct drm_plane *plane,
 		   unsigned long possible_crtcs, enum drm_plane_type type,
 		   unsigned int supported_rotations, const u32 blend_modes,
-		   const u32 *formats, size_t num_formats, unsigned int plane_idx);
+		   const u32 *formats, size_t num_formats,
+		   bool supports_afbc, unsigned int plane_idx);
 #endif
-- 
2.49.0