diff --git a/drivers/gpu/drm/amd/amdgpu/mes_v12_0.c b/drivers/gpu/drm/amd/amdgpu/mes_v12_0.c
index 3b2b955cf82e..ee72afdb0a1d 100644
--- a/drivers/gpu/drm/amd/amdgpu/mes_v12_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/mes_v12_0.c
@@ -993,10 +993,16 @@ static int mes_v12_0_set_hw_resources(struct amdgpu_mes *mes, int pipe)
 	/*
 	 * Keep oversubscribe timer for sdma . When we have unmapped doorbell
 	 * handling support, other queue will not use the oversubscribe timer.
-	 * handling  mode - 0: disabled; 1: basic version; 2: basic+ version
+	 * handling  mode - 0: disabled; 1: basic; 2: basic+; 3: basic++
+	 *
+	 * Use basic+ (2): on an unmapped-queue doorbell ring MES reads the
+	 * per-queue CP_UNMAPPED_QUEUE bitmap and clears the ringing queue's
+	 * work_done so it is rescheduled. basic (1) only sets a coarse
+	 * level-wide ready flag without clearing work_done, so a queue that
+	 * rings after work_done was set is skipped and its work is lost.
 	 */
 	mes_set_hw_res_pkt.oversubscription_timer = mes_rev < 0x8b ? 0 : 50;
-	mes_set_hw_res_pkt.unmapped_doorbell_handling = 1;
+	mes_set_hw_res_pkt.unmapped_doorbell_handling = 2;
 
 	if (amdgpu_mes_log_enable) {
 		mes_set_hw_res_pkt.enable_mes_event_int_logging = 1;