From: Martin Tsai <martin.tsai@amd.com>
Date: Thu, 10 Jan 2019 05:05:15 +0000 (+0800)
Subject: drm/amd/display: Poll pending down rep before clear payload allocation table
X-Git-Tag: Ubuntu-5.13.0-19.19~9032^2~16^2~9
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=22051b636e347888bfd2efbbc9bcb8918d16e8c5;p=mirror_ubuntu-jammy-kernel.git

drm/amd/display: Poll pending down rep before clear payload allocation table

[Why]
On current design, driver cannot handle the interrupt for
down reply when link training is processing. The DOWN REQ
send before link training will keep in the pending DOWN REP
state in the queue.
It makes the next DOWN REQ be queued until time out.

[How]
To add a polling sequence before clear payload allocation table
to make sure the pending DOWN REP can be handled.

Signed-off-by: Martin Tsai <martin.tsai@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index e6ab0186955c..cae16b6d2344 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -263,6 +263,13 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 	return true;
 }
 
+/*
+ * poll pending down reply before clear payload allocation table
+ */
+void dm_helpers_dp_mst_poll_pending_down_reply(
+	struct dc_context *ctx,
+	const struct dc_link *link)
+{}
 
 /*
  * Clear payload allocation table before enable MST DP link.
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
index 3dd5f2717b53..8ff5d42587c2 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c
@@ -1467,6 +1467,11 @@ static enum dc_status enable_link_dp_mst(
 	if (link->cur_link_settings.lane_count != LANE_COUNT_UNKNOWN)
 		return DC_OK;
 
+	/* to make sure the pending down rep can be processed
+	 * before clear payload table
+	 */
+	dm_helpers_dp_mst_poll_pending_down_reply(link->ctx, link);
+
 	/* clear payload table */
 	dm_helpers_dp_mst_clear_payload_allocation_table(link->ctx, link);
 
diff --git a/drivers/gpu/drm/amd/display/dc/dm_helpers.h b/drivers/gpu/drm/amd/display/dc/dm_helpers.h
index 5d4527d03045..e81b24374bcb 100644
--- a/drivers/gpu/drm/amd/display/dc/dm_helpers.h
+++ b/drivers/gpu/drm/amd/display/dc/dm_helpers.h
@@ -57,6 +57,13 @@ bool dm_helpers_dp_mst_write_payload_allocation_table(
 		struct dp_mst_stream_allocation_table *proposed_table,
 		bool enable);
 
+/*
+ * poll pending down reply before clear payload allocation table
+ */
+void dm_helpers_dp_mst_poll_pending_down_reply(
+	struct dc_context *ctx,
+	const struct dc_link *link);
+
 /*
  * Clear payload allocation table before enable MST DP link.
  */