From: Shirish S <shirish.s@amd.com>
Date: Tue, 13 Feb 2018 14:11:37 +0530
Subject: drm/amd/display: validate plane in dce110 for scaling
Git-commit: 10eee2e873ec8bc0cad6240d57d130e00edd6a9f
Patch-mainline: v4.16-rc5
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

CZ & ST support uptil a limit 2:1 downscaling, this patch
adds validate_plane hook, that shall be used to validate
the plane attributes sent by the user space based
on dce110 capabilities.

Signed-off-by: Shirish S <shirish.s@amd.com>
Reviewed-by: Harry Wentland <Harry.Wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/amd/display/dc/dce110/dce110_resource.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_resource.c
@@ -846,6 +846,16 @@ static bool dce110_validate_bandwidth(
 	return result;
 }
 
+enum dc_status dce110_validate_plane(const struct dc_plane_state *plane_state,
+				     struct dc_caps *caps)
+{
+	if (((plane_state->dst_rect.width * 2) < plane_state->src_rect.width) ||
+	    ((plane_state->dst_rect.height * 2) < plane_state->src_rect.height))
+		return DC_FAIL_SURFACE_VALIDATE;
+
+	return DC_OK;
+}
+
 static bool dce110_validate_surface_sets(
 		struct dc_state *context)
 {
@@ -1021,6 +1031,7 @@ static const struct resource_funcs dce11
 	.link_enc_create = dce110_link_encoder_create,
 	.validate_guaranteed = dce110_validate_guaranteed,
 	.validate_bandwidth = dce110_validate_bandwidth,
+	.validate_plane = dce110_validate_plane,
 	.acquire_idle_pipe_for_layer = dce110_acquire_underlay,
 	.add_stream_to_ctx = dce110_add_stream_to_ctx,
 	.validate_global = dce110_validate_global