[PATCH 07/14] drm/amd/display: Clear encoder assignments when state cleared.

[Aurabindo Pillai]

From: Jimmy Kizito <jimmy.kiz...@amd.com>

[Why]
State can be cleared without removing individual streams (by
calling dc_remove_stream_from_ctx()). This can leave the
encoder assignment module in an incoherent state and cause
future assignments to be incorrect.

[How]
Clear encoder assignments when committing 0 streams or
re-initializing hardware.

Acked-by: Aurabindo Pillai <aurabindo.pil...@amd.com>
Signed-off-by: Jimmy Kizito <jimmy.kiz...@amd.com>
Reviewed-by: Jun Lei <jun....@amd.com>
---
 .../drm/amd/display/dc/core/dc_link_enc_cfg.c | 22 +++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_enc_cfg.c 
b/drivers/gpu/drm/amd/display/dc/core/dc_link_enc_cfg.c
index 72b0f8594b4a..25e48a8cbb78 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link_enc_cfg.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_enc_cfg.c
@@ -236,6 +236,23 @@ static struct link_encoder *get_link_enc_used_by_link(
 
        return link_enc;
 }
+/* Clear all link encoder assignments. */
+static void clear_enc_assignments(struct dc_state *state)
+{
+       int i;
+       enum engine_id eng_id;
+       struct dc_stream_state *stream;
+
+       for (i = 0; i < MAX_PIPES; i++) {
+               state->res_ctx.link_enc_cfg_ctx.link_enc_assignments[i].valid = 
false;
+               eng_id = 
state->res_ctx.link_enc_cfg_ctx.link_enc_assignments[i].eng_id;
+               stream = 
state->res_ctx.link_enc_cfg_ctx.link_enc_assignments[i].stream;
+               if (eng_id != ENGINE_ID_UNKNOWN)
+                       state->res_ctx.link_enc_cfg_ctx.link_enc_avail[eng_id - 
ENGINE_ID_DIGA] = eng_id;
+               if (stream)
+                       stream->link_enc = NULL;
+       }
+}
 
 void link_enc_cfg_init(
                struct dc *dc,
@@ -250,6 +267,8 @@ void link_enc_cfg_init(
                        state->res_ctx.link_enc_cfg_ctx.link_enc_avail[i] = 
ENGINE_ID_UNKNOWN;
        }
 
+       clear_enc_assignments(state);
+
        state->res_ctx.link_enc_cfg_ctx.mode = LINK_ENC_CFG_STEADY;
 }
 
@@ -265,6 +284,9 @@ void link_enc_cfg_link_encs_assign(
 
        ASSERT(state->stream_count == stream_count);
 
+       if (stream_count == 0)
+               clear_enc_assignments(state);
+
        /* Release DIG link encoder resources before running assignment 
algorithm. */
        for (i = 0; i < stream_count; i++)
                dc->res_pool->funcs->link_enc_unassign(state, streams[i]);
-- 
2.30.2