The HVS spec recommends using PPF when the downscaling ratio is between 2/3 and 1. Let's modify vc4_get_scaling_mode() to follow this recommendation.
Signed-off-by: Boris Brezillon boris.brezillon@bootlin.com --- drivers/gpu/drm/vc4/vc4_plane.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c index 5950e6b6b7f0..1d0d91e50aaf 100644 --- a/drivers/gpu/drm/vc4/vc4_plane.c +++ b/drivers/gpu/drm/vc4/vc4_plane.c @@ -129,12 +129,12 @@ static const struct hvs_format *vc4_get_hvs_format(u32 drm_format)
static enum vc4_scaling_mode vc4_get_scaling_mode(u32 src, u32 dst) { - if (dst > src) + if (dst == src) + return VC4_SCALING_NONE; + if (3 * dst >= 2 * src) return VC4_SCALING_PPF; - else if (dst < src) - return VC4_SCALING_TPZ; else - return VC4_SCALING_NONE; + return VC4_SCALING_TPZ; }
static bool plane_enabled(struct drm_plane_state *state)