drm/i915: Check fb stride against plane max stride

commit 4e0b83a567e2 ("drm/i915: Extract per-platform plane->check()
functions") removed the plane max stride check for sprite planes.
I was going to add it back when introducing GTT remapping for the
display, but after further thought it seems better to re-introduce
it separately.

So let's add the max stride check back. And let's do it in a nicer
form than what we had before and do it for all plane types (easy
now that we have the ->max_stride() plane vfunc).

Only sprite planes really need this for now since primary planes
are capable of scanning out the current max fb size we allow, and
cursors have more stringent stride checks elsewhere.

Cc: José Roberto de Souza <jose.souza@intel.com>
Fixes: 4e0b83a567e2 ("drm/i915: Extract per-platform plane->check() functions")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180918140243.12207-1-ville.syrjala@linux.intel.com
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 96de5a33dbaf..d9e407d837b9 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -230,6 +230,28 @@ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state)
 #endif
 }
 
+int intel_plane_check_stride(const struct intel_plane_state *plane_state)
+{
+	struct intel_plane *plane = to_intel_plane(plane_state->base.plane);
+	const struct drm_framebuffer *fb = plane_state->base.fb;
+	unsigned int rotation = plane_state->base.rotation;
+	u32 stride, max_stride;
+
+	/* FIXME other color planes? */
+	stride = plane_state->color_plane[0].stride;
+	max_stride = plane->max_stride(plane, fb->format->format,
+				       fb->modifier, rotation);
+
+	if (stride > max_stride) {
+		DRM_DEBUG_KMS("[FB:%d] stride (%d) exceeds [PLANE:%d:%s] max stride (%d)\n",
+			      fb->base.id, stride,
+			      plane->base.base.id, plane->base.name, max_stride);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 int intel_plane_check_src_coordinates(struct intel_plane_state *plane_state)
 {
 	const struct drm_framebuffer *fb = plane_state->base.fb;