drm/vc4: Add support for X/Y reflection

Add support for X/Y reflection when the plane is using linear or
T-tiled formats. X/Y reflection hasn't been tested on SAND formats, so
we reject them until proper testing/debugging has been done.

Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20181207083606.15449-2-boris.brezillon@bootlin.com

1 files changed, 47 insertions, 12 deletions

diff --git a/drivers/gpu/drm/vc4/vc4_plane.c b/drivers/gpu/drm/vc4/vc4_plane.c
index fb1214b91a25..283abd7d1e9b 100644
--- a/drivers/gpu/drm/vc4/vc4_plane.c
+++ b/drivers/gpu/drm/vc4/vc4_plane.c
@@ -492,8 +492,9 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
         bool mix_plane_alpha;
         bool covers_screen;
         u32 scl0, scl1, pitch0;
-        u32 tiling;
+        u32 tiling, src_y;
         u32 hvs_format = format->hvs;
+        unsigned int rotation;
         int ret, i;
 
         if (vc4_state->dlist_initialized)
@@ -520,6 +521,16 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
         h_subsample = drm_format_horz_chroma_subsampling(format->drm);
         v_subsample = drm_format_vert_chroma_subsampling(format->drm);
 
+        rotation = drm_rotation_simplify(state->rotation,
+                                         DRM_MODE_ROTATE_0 |
+                                         DRM_MODE_REFLECT_X |
+                                         DRM_MODE_REFLECT_Y);
+
+        /* We must point to the last line when Y reflection is enabled. */
+        src_y = vc4_state->src_y;
+        if (rotation & DRM_MODE_REFLECT_Y)
+                src_y += vc4_state->src_h[0] - 1;
+
         switch (base_format_mod) {
         case DRM_FORMAT_MOD_LINEAR:
                 tiling = SCALER_CTL0_TILING_LINEAR;
@@ -529,9 +540,10 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
                  * out.
                  */
                 for (i = 0; i < num_planes; i++) {
-                        vc4_state->offsets[i] += vc4_state->src_y /
+                        vc4_state->offsets[i] += src_y /
                                                  (i ? v_subsample : 1) *
                                                  fb->pitches[i];
+
                         vc4_state->offsets[i] += vc4_state->src_x /
                                                  (i ? h_subsample : 1) *
                                                  fb->format->cpp[i];
@@ -557,22 +569,38 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
                 u32 tiles_w = fb->pitches[0] >> (tile_size_shift - tile_h_shift);
                 u32 tiles_l = vc4_state->src_x >> tile_w_shift;
                 u32 tiles_r = tiles_w - tiles_l;
-                u32 tiles_t = vc4_state->src_y >> tile_h_shift;
+                u32 tiles_t = src_y >> tile_h_shift;
                 /* Intra-tile offsets, which modify the base address (the
                  * SCALER_PITCH0_TILE_Y_OFFSET tells HVS how to walk from that
                  * base address).
                  */
-                u32 tile_y = (vc4_state->src_y >> 4) & 1;
-                u32 subtile_y = (vc4_state->src_y >> 2) & 3;
-                u32 utile_y = vc4_state->src_y & 3;
+                u32 tile_y = (src_y >> 4) & 1;
+                u32 subtile_y = (src_y >> 2) & 3;
+                u32 utile_y = src_y & 3;
                 u32 x_off = vc4_state->src_x & tile_w_mask;
-                u32 y_off = vc4_state->src_y & tile_h_mask;
+                u32 y_off = src_y & tile_h_mask;
+
+                /* When Y reflection is requested we must set the
+                 * SCALER_PITCH0_TILE_LINE_DIR flag to tell HVS that all lines
+                 * after the initial one should be fetched in descending order,
+                 * which makes sense since we start from the last line and go
+                 * backward.
+                 * Don't know why we need y_off = max_y_off - y_off, but it's
+                 * definitely required (I guess it's also related to the "going
+                 * backward" situation).
+                 */
+                if (rotation & DRM_MODE_REFLECT_Y) {
+                        y_off = tile_h_mask - y_off;
+                        pitch0 = SCALER_PITCH0_TILE_LINE_DIR;
+                } else {
+                        pitch0 = 0;
+                }
 
                 tiling = SCALER_CTL0_TILING_256B_OR_T;
-                pitch0 = (VC4_SET_FIELD(x_off, SCALER_PITCH0_SINK_PIX) |
-                          VC4_SET_FIELD(y_off, SCALER_PITCH0_TILE_Y_OFFSET) |
-                          VC4_SET_FIELD(tiles_l, SCALER_PITCH0_TILE_WIDTH_L) |
-                          VC4_SET_FIELD(tiles_r, SCALER_PITCH0_TILE_WIDTH_R));
+                pitch0 |= (VC4_SET_FIELD(x_off, SCALER_PITCH0_SINK_PIX) |
+                           VC4_SET_FIELD(y_off, SCALER_PITCH0_TILE_Y_OFFSET) |
+                           VC4_SET_FIELD(tiles_l, SCALER_PITCH0_TILE_WIDTH_L) |
+                           VC4_SET_FIELD(tiles_r, SCALER_PITCH0_TILE_WIDTH_R));
                 vc4_state->offsets[0] += tiles_t * (tiles_w << tile_size_shift);
                 vc4_state->offsets[0] += subtile_y << 8;
                 vc4_state->offsets[0] += utile_y << 4;
@@ -643,7 +671,7 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
                  */
                 for (i = 0; i < num_planes; i++) {
                         vc4_state->offsets[i] += param * tile_w * tile;
-                        vc4_state->offsets[i] += vc4_state->src_y /
+                        vc4_state->offsets[i] += src_y /
                                                  (i ? v_subsample : 1) *
                                                  tile_w;
                         vc4_state->offsets[i] += x_off /
@@ -664,6 +692,8 @@ static int vc4_plane_mode_set(struct drm_plane *plane,
         /* Control word */
         vc4_dlist_write(vc4_state,
                         SCALER_CTL0_VALID |
+                        (rotation & DRM_MODE_REFLECT_X ? SCALER_CTL0_HFLIP : 0) |
+                        (rotation & DRM_MODE_REFLECT_Y ? SCALER_CTL0_VFLIP : 0) |
                         VC4_SET_FIELD(SCALER_CTL0_RGBA_EXPAND_ROUND, SCALER_CTL0_RGBA_EXPAND) |
                         (format->pixel_order << SCALER_CTL0_ORDER_SHIFT) |
                         (hvs_format << SCALER_CTL0_PIXEL_FORMAT_SHIFT) |
@@ -1144,6 +1174,11 @@ struct drm_plane *vc4_plane_init(struct drm_device *dev,
         drm_plane_helper_add(plane, &vc4_plane_helper_funcs);
 
         drm_plane_create_alpha_property(plane);
+        drm_plane_create_rotation_property(plane, DRM_MODE_ROTATE_0,
+                                           DRM_MODE_ROTATE_0 |
+                                           DRM_MODE_ROTATE_180 |
+                                           DRM_MODE_REFLECT_X |
+                                           DRM_MODE_REFLECT_Y);
 
         return plane;
 }