drm/amd/display: Exit idle optimizations before HDCP execution

[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 <[email protected]>
Cc: Alex Deucher <[email protected]>
Reviewed-by: Charlene Liu <[email protected]>
Acked-by: Alex Hung <[email protected]>
Signed-off-by: Nicholas Kazlauskas <[email protected]>
Tested-by: Daniel Wheeler <[email protected]>
Signed-off-by: Alex Deucher <[email protected]>

Author: Nicholas Kazlauskas

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)
@@ -543,6 +551,8 @@ 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(

drivers/gpu/drm/amd/display/modules/inc/mod_hdcp.h

@@ -156,6 +156,13 @@ 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;
@@ -272,6 +279,7 @@ 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;
 };