drm/amd/display: Use macro for invalid OPP ID

[WHY]
This is meant to make it clearer that 0xf is not a valid OPP ID, and
that code making use of OPP IDs should not accept this value.
Signed-off-by: Wesley Chalmers <Wesley.Chalmers@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hubp.c

@@ -63,7 +63,7 @@ void hubp1_set_blank(struct hubp *hubp, bool blank)
 		}
 
 		hubp->mpcc_id = 0xf;
-		hubp->opp_id = 0xf;
+		hubp->opp_id = OPP_ID_INVALID;
 	}
 }
 
@@ -1226,7 +1226,7 @@ void dcn10_hubp_construct(
 	hubp1->hubp_shift = hubp_shift;
 	hubp1->hubp_mask = hubp_mask;
 	hubp1->base.inst = inst;
-	hubp1->base.opp_id = 0xf;
+	hubp1->base.opp_id = OPP_ID_INVALID;
 	hubp1->base.mpcc_id = 0xf;
 }
 

drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c

@@ -1025,7 +1025,7 @@ static void dcn10_init_pipes(struct dc *dc, struct dc_state *context)
 		pipe_ctx->plane_res.dpp = dpp;
 		pipe_ctx->plane_res.mpcc_inst = dpp->inst;
 		hubp->mpcc_id = dpp->inst;
-		hubp->opp_id = 0xf;
+		hubp->opp_id = OPP_ID_INVALID;
 		hubp->power_gated = false;
 
 		dc->res_pool->opps[i]->mpc_tree_params.opp_id = dc->res_pool->opps[i]->inst;
@@ -2371,7 +2371,7 @@ static void dcn10_apply_ctx_for_surface(
 		if (pipe_ctx->plane_state && !old_pipe_ctx->plane_state) {
 			if (old_pipe_ctx->stream_res.tg == tg &&
 			    old_pipe_ctx->plane_res.hubp &&
-			    old_pipe_ctx->plane_res.hubp->opp_id != 0xf)
+			    old_pipe_ctx->plane_res.hubp->opp_id != OPP_ID_INVALID)
 				dcn10_disable_plane(dc, old_pipe_ctx);
 		}
 

drivers/gpu/drm/amd/display/dc/inc/hw/hubp.h

@@ -28,6 +28,8 @@
 
 #include "mem_input.h"
 
+#define OPP_ID_INVALID 0xf
+
 
 enum cursor_pitch {
 	CURSOR_PITCH_64_PIXELS = 0,