drm: mali-dp: Add plane upscaling support

Enable the scaling engine for upscaling a single plane using the polyphase
scaler. No image enhancement support or downscaling yet*, and composition
result scaling is not implemented.

* Downscaling a plane requires mclk > pxlclk.

Signed-off-by: Mihail Atanassov <mihail.atanassov@arm.com>
Signed-off-by: Liviu Dudau <Liviu.Dudau@arm.com>

1 files changed, 56 insertions, 17 deletions

diff --git a/drivers/gpu/drm/arm/malidp_planes.c b/drivers/gpu/drm/arm/malidp_planes.c
index 8106e22f9349..814fda23cead 100644
--- a/drivers/gpu/drm/arm/malidp_planes.c
+++ b/drivers/gpu/drm/arm/malidp_planes.c
@@ -25,6 +25,9 @@
 #define MALIDP_LAYER_FORMAT		0x000
 #define MALIDP_LAYER_CONTROL		0x004
 #define   LAYER_ENABLE			(1 << 0)
+#define   LAYER_FLOWCFG_MASK		7
+#define   LAYER_FLOWCFG(x)		(((x) & LAYER_FLOWCFG_MASK) << 1)
+#define     LAYER_FLOWCFG_SCALE_SE	3
 #define   LAYER_ROT_OFFSET		8
 #define   LAYER_H_FLIP			(1 << 10)
 #define   LAYER_V_FLIP			(1 << 11)
@@ -133,16 +136,50 @@ static const struct drm_plane_funcs malidp_de_plane_funcs = {
 	.atomic_print_state = malidp_plane_atomic_print_state,
 };
 
+static int malidp_se_check_scaling(struct malidp_plane *mp,
+				   struct drm_plane_state *state)
+{
+	struct drm_crtc_state *crtc_state =
+		drm_atomic_get_existing_crtc_state(state->state, state->crtc);
+	struct malidp_crtc_state *mc;
+	struct drm_rect clip = { 0 };
+	u32 src_w, src_h;
+	int ret;
+
+	if (!crtc_state)
+		return -EINVAL;
+
+	clip.x2 = crtc_state->adjusted_mode.hdisplay;
+	clip.y2 = crtc_state->adjusted_mode.vdisplay;
+	ret = drm_plane_helper_check_state(state, &clip, 0, INT_MAX, true, true);
+	if (ret)
+		return ret;
+
+	src_w = state->src_w >> 16;
+	src_h = state->src_h >> 16;
+	if ((state->crtc_w == src_w) && (state->crtc_h == src_h)) {
+		/* Scaling not necessary for this plane. */
+		mc->scaled_planes_mask &= ~(mp->layer->id);
+		return 0;
+	}
+
+	if (mp->layer->id & (DE_SMART | DE_GRAPHICS2))
+		return -EINVAL;
+
+	mc = to_malidp_crtc_state(crtc_state);
+
+	mc->scaled_planes_mask |= mp->layer->id;
+	/* Defer scaling requirements calculation to the crtc check. */
+	return 0;
+}
+
 static int malidp_de_plane_check(struct drm_plane *plane,
 				 struct drm_plane_state *state)
 {
 	struct malidp_plane *mp = to_malidp_plane(plane);
 	struct malidp_plane_state *ms = to_malidp_plane_state(state);
-	struct drm_crtc_state *crtc_state;
 	struct drm_framebuffer *fb;
-	struct drm_rect clip = { 0 };
 	int i, ret;
-	u32 src_w, src_h;
 
 	if (!state->crtc || !state->fb)
 		return 0;
@@ -163,9 +200,6 @@ static int malidp_de_plane_check(struct drm_plane *plane,
 		}
 	}
 
-	src_w = state->src_w >> 16;
-	src_h = state->src_h >> 16;
-
 	if ((state->crtc_w > mp->hwdev->max_line_size) ||
 	    (state->crtc_h > mp->hwdev->max_line_size) ||
 	    (state->crtc_w < mp->hwdev->min_line_size) ||
@@ -182,22 +216,16 @@ static int malidp_de_plane_check(struct drm_plane *plane,
 	    (state->fb->pitches[1] != state->fb->pitches[2]))
 		return -EINVAL;
 
+	ret = malidp_se_check_scaling(mp, state);
+	if (ret)
+		return ret;
+
 	/* packed RGB888 / BGR888 can't be rotated or flipped */
 	if (state->rotation != DRM_ROTATE_0 &&
 	    (fb->format->format == DRM_FORMAT_RGB888 ||
 	     fb->format->format == DRM_FORMAT_BGR888))
 		return -EINVAL;
 
-	crtc_state = drm_atomic_get_existing_crtc_state(state->state, state->crtc);
-	clip.x2 = crtc_state->adjusted_mode.hdisplay;
-	clip.y2 = crtc_state->adjusted_mode.vdisplay;
-	ret = drm_plane_helper_check_state(state, &clip,
-					   DRM_PLANE_HELPER_NO_SCALING,
-					   DRM_PLANE_HELPER_NO_SCALING,
-					   true, true);
-	if (ret)
-		return ret;
-
 	ms->rotmem_size = 0;
 	if (state->rotation & MALIDP_ROTATED_MASK) {
 		int val;
@@ -302,6 +330,16 @@ static void malidp_de_plane_update(struct drm_plane *plane,
 	val &= ~LAYER_COMP_MASK;
 	val |= LAYER_COMP_PIXEL;
 
+	val &= ~LAYER_FLOWCFG(LAYER_FLOWCFG_MASK);
+	if (plane->state->crtc) {
+		struct malidp_crtc_state *m =
+			to_malidp_crtc_state(plane->state->crtc->state);
+
+		if (m->scaler_config.scale_enable &&
+		    m->scaler_config.plane_src_id == mp->layer->id)
+			val |= LAYER_FLOWCFG(LAYER_FLOWCFG_SCALE_SE);
+	}
+
 	/* set the 'enable layer' bit */
 	val |= LAYER_ENABLE;
 
@@ -314,7 +352,8 @@ static void malidp_de_plane_disable(struct drm_plane *plane,
 {
 	struct malidp_plane *mp = to_malidp_plane(plane);
 
-	malidp_hw_clearbits(mp->hwdev, LAYER_ENABLE,
+	malidp_hw_clearbits(mp->hwdev,
+			    LAYER_ENABLE | LAYER_FLOWCFG(LAYER_FLOWCFG_MASK),
 			    mp->layer->base + MALIDP_LAYER_CONTROL);
 }