drm/amd/display: Limit HW cursor size of >= 4k

[Description]
- For SubVP, we cannot support HW cursor if it's
  greater than 64 x 64 x 4 bytes in size
- However, on certain config changes (i.e. pixel format)
  we can exit SubVP (then change to HW cursor) then re-enter
  SubVP without changing back to SW cursor because there is
  no SetCursorAttributes call
- To workaround this issue, limit the HW cursor size to be
  less than 64 x 64 x 4 bytes whenever the stream is >= 4K
- Also ensure this W/A only affects DCN that supports SubVP

Reviewed-by: Jun Lei <Jun.Lei@amd.com>
Acked-by: Brian Chang <Brian.Chang@amd.com>
Signed-off-by: Alvin Lee <Alvin.Lee2@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c b/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c
index d17d0f22be1f..06f144189e9d 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn321/dcn321_resource.c
@@ -721,7 +721,7 @@ static const struct dc_debug_options debug_defaults_drv = {
 	/*must match enable_single_display_2to1_odm_policy to support dynamic ODM transitions*/
 	.enable_double_buffered_dsc_pg_support = true,
 	.enable_dp_dig_pixel_rate_div_policy = 1,
-	.allow_sw_cursor_fallback = false,
+	.allow_sw_cursor_fallback = false, // Linux can't do SW cursor "fallback"
 	.alloc_extra_way_for_cursor = true,
 	.min_prefetch_in_strobe_ns = 60000, // 60us
 };