drm/amd/display: Refactor recout calculation with a more generic formula

[Why]
Current recout calculation has a few assumptions and implementation
for MPO + ODM combine calculation is very specific. The equation has
too many cases without enough comments to document the detail.

[How]
The change remove the following assumptions:
1. When MPO is enabled, we only allow ODM Combine 2:1
2. ODM Combine always has even segment width.
3. Secondary MPO plane's pipe_ctx copies pre_odm_pipe from
its top pipe.

The change applies a generic formula with more details in comment to
document this solution so it is eaiser to learn and debug later.
Reviewed-by: Dmytro Laktyushkin <dmytro.laktyushkin@amd.com>
Acked-by: Alex Hung <alex.hung@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn21/dcn21_resource.c

@@ -854,8 +854,8 @@ bool dcn21_fast_validate_bw(struct dc *dc,
 		/* We only support full screen mpo with ODM */
 		if (vba->ODMCombineEnabled[vba->pipe_plane[pipe_idx]] != dm_odm_combine_mode_disabled
 				&& pipe->plane_state && mpo_pipe
-				&& memcmp(&mpo_pipe->plane_res.scl_data.recout,
-						&pipe->plane_res.scl_data.recout,
+				&& memcmp(&mpo_pipe->plane_state->clip_rect,
+						&pipe->stream->src,
 						sizeof(struct rect)) != 0) {
 			ASSERT(mpo_pipe->plane_state != pipe->plane_state);
 			goto validate_fail;

drivers/gpu/drm/amd/display/dc/dcn30/dcn30_resource.c

@@ -1705,8 +1705,8 @@ noinline bool dcn30_internal_validate_bw(
 			/* We only support full screen mpo with ODM */
 			if (vba->ODMCombineEnabled[vba->pipe_plane[pipe_idx]] != dm_odm_combine_mode_disabled
 					&& pipe->plane_state && mpo_pipe
-					&& memcmp(&mpo_pipe->plane_res.scl_data.recout,
-							&pipe->plane_res.scl_data.recout,
+					&& memcmp(&mpo_pipe->plane_state->clip_rect,
+							&pipe->stream->src,
 							sizeof(struct rect)) != 0) {
 				ASSERT(mpo_pipe->plane_state != pipe->plane_state);
 				goto validate_fail;

drivers/gpu/drm/amd/display/dc/dml/dcn32/dcn32_fpu.c

@@ -1717,8 +1717,8 @@ bool dcn32_internal_validate_bw(struct dc *dc,
 		if (vba->ODMCombineEnabled[vba->pipe_plane[pipe_idx]] != dm_odm_combine_mode_disabled
 				&& !dc->config.enable_windowed_mpo_odm
 				&& pipe->plane_state && mpo_pipe
-				&& memcmp(&mpo_pipe->plane_res.scl_data.recout,
-						&pipe->plane_res.scl_data.recout,
+				&& memcmp(&mpo_pipe->plane_state->clip_rect,
+						&pipe->stream->src,
 						sizeof(struct rect)) != 0) {
 			ASSERT(mpo_pipe->plane_state != pipe->plane_state);
 			goto validate_fail;