[Intel-gfx] [PATCH 09/10] drm/i915: Use fb->pitches[0] in cursor code

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

The cursor code currently ignores fb->pitches[0] (except when creating
the fb itself), and just uses the cursor_width*4 as the stride. Let's
make sure fb->pitches[0] actually matches what we expect it to be.

We can also relax the stride vs. cursor width relationship on 845/865
since the stride is programmed separately. The only constraint is that
width*cpp doesn't exceed the stride, and that's already been checked
by the core since it makes sure the entire plane fits within the fb.

We can also drop the bo size check as that's already checked when
we create the fb. That is the fb is guaranteed to fit within the bo.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/intel_display.c | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 41cbaee66f1b..17362dc9f438 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9300,8 +9300,6 @@ static int i845_check_cursor(struct intel_plane *plane,
 			     struct intel_plane_state *state)
 {
 	struct drm_framebuffer *fb = state->base.fb;
-	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
-	unsigned stride;
 	int ret;
 
 	ret = drm_plane_helper_check_state(&state->base,
@@ -9313,7 +9311,7 @@ static int i845_check_cursor(struct intel_plane *plane,
 		return ret;
 
 	/* if we want to turn off the cursor ignore width and height */
-	if (!obj)
+	if (!fb)
 		return 0;
 
 	/* Check for which cursor types we support */
@@ -9323,10 +9321,16 @@ static int i845_check_cursor(struct intel_plane *plane,
 		return -EINVAL;
 	}
 
-	stride = roundup_pow_of_two(state->base.crtc_w) * 4;
-	if (obj->base.size < stride * state->base.crtc_h) {
-		DRM_DEBUG_KMS("buffer is too small\n");
-		return -ENOMEM;
+	switch (fb->pitches[0]) {
+	case 256:
+	case 512:
+	case 1024:
+	case 2048:
+		break;
+	default:
+		DRM_DEBUG_KMS("Invalid cursor stride (%u)\n",
+			      fb->pitches[0]);
+		return -EINVAL;
 	}
 
 	if (fb->modifier != DRM_FORMAT_MOD_NONE) {
@@ -9430,9 +9434,7 @@ static int i9xx_check_cursor(struct intel_plane *plane,
 {
 	struct drm_i915_private *dev_priv = to_i915(plane->base.dev);
 	struct drm_framebuffer *fb = state->base.fb;
-	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
 	enum pipe pipe = plane->pipe;
-	unsigned stride;
 	int ret;
 
 	ret = drm_plane_helper_check_state(&state->base,
@@ -9444,7 +9446,7 @@ static int i9xx_check_cursor(struct intel_plane *plane,
 		return ret;
 
 	/* if we want to turn off the cursor ignore width and height */
-	if (!obj)
+	if (!fb)
 		return 0;
 
 	/* Check for which cursor types we support */
@@ -9454,10 +9456,10 @@ static int i9xx_check_cursor(struct intel_plane *plane,
 		return -EINVAL;
 	}
 
-	stride = roundup_pow_of_two(state->base.crtc_w) * 4;
-	if (obj->base.size < stride * state->base.crtc_h) {
-		DRM_DEBUG_KMS("buffer is too small\n");
-		return -ENOMEM;
+	if (fb->pitches[0] != state->base.crtc_w * fb->format->cpp[0]) {
+		DRM_DEBUG_KMS("Invalid cursor stride (%u) (cursor width %d)\n",
+			      fb->pitches[0], state->base.crtc_w);
+		return -EINVAL;
 	}
 
 	if (fb->modifier != DRM_FORMAT_MOD_NONE) {
-- 
2.10.2