drm/amd/display: fix mirror rotation scaling math

Curretly dc will incorrectly calculate viewport when there is
rotation or mirror being applied

Signed-off-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Reviewed-by: Su Chung <Su.Chung@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
index d68906b..fc65b00 100644 (file)
--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -499,8 +499,13 @@ static void calculate_viewport(struct pipe_ctx *pipe_ctx)
                        pipe_ctx->top_pipe->plane_state == pipe_ctx->plane_state;
        bool flip_vert_scan_dir = false, flip_horz_scan_dir = false;
 
+
        /*
-        * Need to calculate the scan direction for viewport to properly determine offset
+        * We need take horizontal mirror into account. On an unrotated surface this means
+        * that the viewport offset is actually the offset from the other side of source
+        * image so we have to subtract the right edge of the viewport from the right edge of
+        * the source window. Similar to mirror we need to take into account how offset is
+        * affected for 270/180 rotations
         */
        if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_180) {
                flip_vert_scan_dir = true;
@@ -510,6 +515,9 @@ static void calculate_viewport(struct pipe_ctx *pipe_ctx)
        else if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_270)
                flip_horz_scan_dir = true;
 
+       if (pipe_ctx->plane_state->horizontal_mirror)
+               flip_horz_scan_dir = !flip_horz_scan_dir;
+
        if (stream->view_format == VIEW_3D_FORMAT_SIDE_BY_SIDE ||
                stream->view_format == VIEW_3D_FORMAT_TOP_AND_BOTTOM) {
                pri_split = false;
@@ -540,45 +548,27 @@ static void calculate_viewport(struct pipe_ctx *pipe_ctx)
                        plane_state->clip_rect.y + plane_state->clip_rect.height - clip.y ;
 
        /* offset = surf_src.ofs + (clip.ofs - surface->dst_rect.ofs) * scl_ratio
+        * note: surf_src.ofs should be added after rotation/mirror offset direction
+        *       adjustment since it is already in viewport space
         * num_pixels = clip.num_pix * scl_ratio
         */
-       data->viewport.x = surf_src.x + (clip.x - plane_state->dst_rect.x) *
+       data->viewport.x = (clip.x - plane_state->dst_rect.x) *
                        surf_src.width / plane_state->dst_rect.width;
        data->viewport.width = clip.width *
                        surf_src.width / plane_state->dst_rect.width;
 
-       data->viewport.y = surf_src.y + (clip.y - plane_state->dst_rect.y) *
+       data->viewport.y = (clip.y - plane_state->dst_rect.y) *
                        surf_src.height / plane_state->dst_rect.height;
        data->viewport.height = clip.height *
                        surf_src.height / plane_state->dst_rect.height;
 
-       /* To transfer the x, y to correct coordinate on mirror image (camera).
-        * deg  0 : transfer x,
-        * deg 90 : don't need to transfer,
-        * deg180 : transfer y,
-        * deg270 : transfer x and y.
-        * To transfer the x, y to correct coordinate on non-mirror image (video).
-        * deg  0 : don't need to transfer,
-        * deg 90 : transfer y,
-        * deg180 : transfer x and y,
-        * deg270 : transfer x.
-        */
-       if (pipe_ctx->plane_state->horizontal_mirror) {
-               if (flip_horz_scan_dir && !flip_vert_scan_dir) {
-                       data->viewport.y = surf_src.height - data->viewport.y - data->viewport.height;
-                       data->viewport.x = surf_src.width - data->viewport.x - data->viewport.width;
-               } else if (flip_horz_scan_dir && flip_vert_scan_dir)
-                       data->viewport.y = surf_src.height - data->viewport.y - data->viewport.height;
-               else {
-                       if (!flip_horz_scan_dir && !flip_vert_scan_dir)
-                               data->viewport.x = surf_src.width - data->viewport.x - data->viewport.width;
-               }
-       } else {
-               if (flip_horz_scan_dir)
-                       data->viewport.x = surf_src.width - data->viewport.x - data->viewport.width;
-               if (flip_vert_scan_dir)
-                       data->viewport.y = surf_src.height - data->viewport.y - data->viewport.height;
-       }
+       if (flip_vert_scan_dir)
+               data->viewport.y = surf_src.height - data->viewport.y - data->viewport.height;
+       if (flip_horz_scan_dir)
+               data->viewport.x = surf_src.width - data->viewport.x - data->viewport.width;
+
+       data->viewport.x += surf_src.x;
+       data->viewport.y += surf_src.y;
 
        /* Round down, compensate in init */
        data->viewport_c.x = data->viewport.x / vpc_div;
@@ -773,22 +763,15 @@ static void calculate_inits_and_adj_vp(struct pipe_ctx *pipe_ctx, struct rect *r
        else if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_270)
                flip_horz_scan_dir = true;
 
+       if (pipe_ctx->plane_state->horizontal_mirror)
+                       flip_horz_scan_dir = !flip_horz_scan_dir;
+
        if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_90 ||
                        pipe_ctx->plane_state->rotation == ROTATION_ANGLE_270) {
                rect_swap_helper(&src);
                rect_swap_helper(&data->viewport_c);
                rect_swap_helper(&data->viewport);
-
-               if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_270 &&
-                       pipe_ctx->plane_state->horizontal_mirror) {
-                       flip_vert_scan_dir = true;
-               }
-               if (pipe_ctx->plane_state->rotation == ROTATION_ANGLE_90 &&
-                       pipe_ctx->plane_state->horizontal_mirror) {
-                       flip_vert_scan_dir = false;
-               }
-       } else if (pipe_ctx->plane_state->horizontal_mirror)
-                       flip_horz_scan_dir = !flip_horz_scan_dir;
+       }
 
        /*
         * Init calculated according to formula: