From: Roman Li <Roman.Li@amd.com>
Date: Fri, 29 Dec 2017 17:45:03 -0500
Subject: drm/amd/display: Fix null-derefs on non-dcn builds
Git-commit: bc373a890f14958c98e476e38b0a71adab3fc733
Patch-mainline: v4.17-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

Fixing regression introduced by
'Use real BE and FE index to program regs.'

Signed-off-by: Roman Li <Roman.Li@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-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/core/dc_resource.c           |    3 ++-
 drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c |    3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_resource.c
@@ -1407,7 +1407,8 @@ static int acquire_first_free_pipe(
 			pipe_ctx->plane_res.xfm = pool->transforms[i];
 			pipe_ctx->plane_res.dpp = pool->dpps[i];
 			pipe_ctx->stream_res.opp = pool->opps[i];
-			pipe_ctx->plane_res.mpcc_inst = pool->dpps[i]->inst;
+			if (pool->dpps[i])
+				pipe_ctx->plane_res.mpcc_inst = pool->dpps[i]->inst;
 			pipe_ctx->pipe_idx = i;
 
 
--- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
+++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c
@@ -2822,7 +2822,8 @@ static void dce110_apply_ctx_for_surface
 
 static void dce110_power_down_fe(struct dc *dc, struct pipe_ctx *pipe_ctx)
 {
-	int fe_idx = pipe_ctx->plane_res.mi->inst;
+	int fe_idx = pipe_ctx->plane_res.mi ?
+		pipe_ctx->plane_res.mi->inst : pipe_ctx->pipe_idx;
 
 	/* Do not power down fe when stream is active on dce*/
 	if (dc->current_state->res_ctx.pipe_ctx[fe_idx].stream)