drm/msm/mdp5: Use plane helpers to configure src/dst rectangles

The MDP5 plane's atomic_check ops doesn't perform clipping tests.
This didn't hurt us much in the past, but clipping becomes important
with cursor planes.

Use drm_plane_helper_check_state, the way rockchip/intel/mtk drivers
already do. Use these drivers as reference.

Clipping requires knowledge of the crtc width and height. This requires
us to call drm_atomic_helper_check_modeset before
drm_atomic_helper_check_planes in the driver's atomic_check op, because
check_modetest will populate the mode for the crtc, needed to populate
the clip rectangle.

We update the plane_enabled(state) local helper to use state->visible,
since state->visible and 'state->fb && state->crtc' represent the same
thing.

One issue with the existing code is that we don't have a way to disable
the plane when it's completely clipped out. Until there isn't an update
on the crtc (which would de-stage the plane), we would still see the
plane in its last 'visible' configuration.

Signed-off-by: Archit Taneja <architt@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/mdp/mdp5/mdp5_plane.c

@@ -29,10 +29,7 @@ struct mdp5_plane {
 
 static int mdp5_plane_mode_set(struct drm_plane *plane,
 		struct drm_crtc *crtc, struct drm_framebuffer *fb,
-		int crtc_x, int crtc_y,
+		struct drm_rect *src, struct drm_rect *dest);
-		unsigned int crtc_w, unsigned int crtc_h,
-		uint32_t src_x, uint32_t src_y,
-		uint32_t src_w, uint32_t src_h);
 
 static void set_scanout_locked(struct drm_plane *plane,
 		struct drm_framebuffer *fb);
@@ -45,7 +42,7 @@ static struct mdp5_kms *get_kms(struct drm_plane *plane)
 
 static bool plane_enabled(struct drm_plane_state *state)
 {
-	return state->fb && state->crtc;
+	return state->visible;
 }
 
 static void mdp5_plane_destroy(struct drm_plane *plane)
@@ -272,6 +269,7 @@ static void mdp5_plane_cleanup_fb(struct drm_plane *plane,
 	msm_framebuffer_cleanup(fb, mdp5_kms->id);
 }
 
+#define FRAC_16_16(mult, div)    (((mult) << 16) / (div))
 static int mdp5_plane_atomic_check(struct drm_plane *plane,
 		struct drm_plane_state *state)
 {
@@ -281,10 +279,19 @@ static int mdp5_plane_atomic_check(struct drm_plane *plane,
 	bool new_hwpipe = false;
 	uint32_t max_width, max_height;
 	uint32_t caps = 0;
+	struct drm_crtc *crtc;
+	struct drm_crtc_state *crtc_state;
+	struct drm_rect clip;
+	int min_scale, max_scale;
+	int ret;
 
 	DBG("%s: check (%d -> %d)", plane->name,
 			plane_enabled(old_state), plane_enabled(state));
 
+	crtc = state->crtc ? state->crtc : plane->state->crtc;
+	if (!crtc)
+		return 0;
+
 	max_width = config->hw->lm.max_width << 16;
 	max_height = config->hw->lm.max_height << 16;
 
@@ -296,6 +303,22 @@ static int mdp5_plane_atomic_check(struct drm_plane *plane,
 		return -ERANGE;
 	}
 
+	crtc_state = drm_atomic_get_existing_crtc_state(state->state, crtc);
+	if (WARN_ON(!crtc_state))
+		return -EINVAL;
+
+	clip.x1 = 0;
+	clip.y1 = 0;
+	clip.x2 = crtc_state->adjusted_mode.hdisplay;
+	clip.y2 = crtc_state->adjusted_mode.vdisplay;
+	min_scale = FRAC_16_16(1, 8);
+	max_scale = FRAC_16_16(8, 1);
+
+	ret = drm_plane_helper_check_state(state, &clip, min_scale,
+					   max_scale, true, true);
+	if (ret)
+		return ret;
+
 	if (plane_enabled(state)) {
 		unsigned int rotation;
 		const struct mdp_format *format;
@@ -368,10 +391,7 @@ static void mdp5_plane_atomic_update(struct drm_plane *plane,
 
 		ret = mdp5_plane_mode_set(plane,
 				state->crtc, state->fb,
-				state->crtc_x, state->crtc_y,
+				&state->src, &state->dst);
-				state->crtc_w, state->crtc_h,
-				state->src_x,  state->src_y,
-				state->src_w, state->src_h);
 		/* atomic_check should have ensured that this doesn't fail */
 		WARN_ON(ret < 0);
 	}
@@ -664,10 +684,7 @@ static void mdp5_write_pixel_ext(struct mdp5_kms *mdp5_kms, enum mdp5_pipe pipe,
 
 static int mdp5_plane_mode_set(struct drm_plane *plane,
 		struct drm_crtc *crtc, struct drm_framebuffer *fb,
-		int crtc_x, int crtc_y,
+		struct drm_rect *src, struct drm_rect *dest)
-		unsigned int crtc_w, unsigned int crtc_h,
-		uint32_t src_x, uint32_t src_y,
-		uint32_t src_w, uint32_t src_h)
 {
 	struct drm_plane_state *pstate = plane->state;
 	struct mdp5_hw_pipe *hwpipe = to_mdp5_plane_state(pstate)->hwpipe;
@@ -683,6 +700,10 @@ static int mdp5_plane_mode_set(struct drm_plane *plane,
 	uint32_t pix_format;
 	unsigned int rotation;
 	bool vflip, hflip;
+	int crtc_x, crtc_y;
+	unsigned int crtc_w, crtc_h;
+	uint32_t src_x, src_y;
+	uint32_t src_w, src_h;
 	unsigned long flags;
 	int ret;
 
@@ -695,6 +716,16 @@ static int mdp5_plane_mode_set(struct drm_plane *plane,
 	format = to_mdp_format(msm_framebuffer_format(fb));
 	pix_format = format->base.pixel_format;
 
+	src_x = src->x1;
+	src_y = src->y1;
+	src_w = drm_rect_width(src);
+	src_h = drm_rect_height(src);
+
+	crtc_x = dest->x1;
+	crtc_y = dest->y1;
+	crtc_w = drm_rect_width(dest);
+	crtc_h = drm_rect_height(dest);
+
 	/* src values are in Q16 fixed point, convert to integer: */
 	src_x = src_x >> 16;
 	src_y = src_y >> 16;

drivers/gpu/drm/msm/msm_atomic.c

@@ -151,20 +151,29 @@ static void commit_worker(struct work_struct *work)
 	complete_commit(container_of(work, struct msm_commit, work), true);
 }
 
+/*
+ * this func is identical to the drm_atomic_helper_check, but we keep this
+ * because we might eventually need to have a more finegrained check
+ * sequence without using the atomic helpers.
+ *
+ * In the past, we first called drm_atomic_helper_check_planes, and then
+ * drm_atomic_helper_check_modeset. We needed this because the MDP5 plane's
+ * ->atomic_check could update ->mode_changed for pixel format changes.
+ * This, however isn't needed now because if there is a pixel format change,
+ * we just assign a new hwpipe for it with a new SMP allocation. We might
+ * eventually hit a condition where we would need to do a full modeset if
+ * we run out of planes. There, we'd probably need to set mode_changed.
+ */
 int msm_atomic_check(struct drm_device *dev,
 		     struct drm_atomic_state *state)
 {
 	int ret;
 
-	/*
+	ret = drm_atomic_helper_check_modeset(dev, state);
-	 * msm ->atomic_check can update ->mode_changed for pixel format
-	 * changes, hence must be run before we check the modeset changes.
-	 */
-	ret = drm_atomic_helper_check_planes(dev, state);
 	if (ret)
 		return ret;
 
-	ret = drm_atomic_helper_check_modeset(dev, state);
+	ret = drm_atomic_helper_check_planes(dev, state);
 	if (ret)
 		return ret;