[PATCH AUTOSEL 5.15 1/6] drm/amd/display: Exit idle optimizations before HDCP execution

[Sasha Levin <sashal@xxxxxxxxxx>]

From: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>

[ Upstream commit f30a3bea92bdab398531129d187629fb1d28f598 ]

[WHY]
PSP can access DCN registers during command submission and we need
to ensure that DCN is not in PG before doing so.

[HOW]
Add a callback to DM to lock and notify DC for idle optimization exit.
It can't be DC directly because of a potential race condition with the
link protection thread and the rest of DM operation.

Cc: Mario Limonciello <mario.limonciello@xxxxxxx>
Cc: Alex Deucher <alexander.deucher@xxxxxxx>
Reviewed-by: Charlene Liu <charlene.liu@xxxxxxx>
Acked-by: Alex Hung <alex.hung@xxxxxxx>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c    | 10 ++++++++++
 drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h |  8 ++++++++
 2 files changed, 18 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c b/drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c
index 3e81850a7ffe3..47bb973669d85 100644
--- a/drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c
+++ b/drivers/gpu/drm/amd/display/modules/hdcp/hdcp.c
@@ -88,6 +88,14 @@ static uint8_t is_cp_desired_hdcp2(struct mod_hdcp *hdcp)
 			!hdcp->connection.is_hdcp2_revoked;
 }
 
+static void exit_idle_optimizations(struct mod_hdcp *hdcp)
+{
+	struct mod_hdcp_dm *dm = &hdcp->config.dm;
+
+	if (dm->funcs.exit_idle_optimizations)
+		dm->funcs.exit_idle_optimizations(dm->handle);
+}
+
 static enum mod_hdcp_status execution(struct mod_hdcp *hdcp,
 		struct mod_hdcp_event_context *event_ctx,
 		union mod_hdcp_transition_input *input)
@@ -507,6 +515,8 @@ enum mod_hdcp_status mod_hdcp_process_event(struct mod_hdcp *hdcp,
 	memset(&event_ctx, 0, sizeof(struct mod_hdcp_event_context));
 	event_ctx.event = event;
 
+	exit_idle_optimizations(hdcp);
+
 	/* execute and transition */
 	exec_status = execution(hdcp, &event_ctx, &hdcp->auth.trans_input);
 	trans_status = transition(
diff --git a/drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h b/drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h
index f37101f5a7777..8a620c34396c7 100644
--- a/drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h
+++ b/drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h
@@ -154,6 +154,13 @@ struct mod_hdcp_ddc {
 	} funcs;
 };
 
+struct mod_hdcp_dm {
+	void *handle;
+	struct {
+		void (*exit_idle_optimizations)(void *handle);
+	} funcs;
+};
+
 struct mod_hdcp_psp {
 	void *handle;
 	void *funcs;
@@ -269,6 +276,7 @@ struct mod_hdcp_display_query {
 struct mod_hdcp_config {
 	struct mod_hdcp_psp psp;
 	struct mod_hdcp_ddc ddc;
+	struct mod_hdcp_dm dm;
 	uint8_t index;
 };
 
-- 
2.43.0