diff --git a/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c b/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c
index 63009db8b5a7237476ea690032c7ad6004e775ba..d156eeef466f9f08962c7c29de5b9ca1b6353cfa 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dce_dmcu.c
@@ -586,7 +586,8 @@ static void dcn10_dmcu_set_psr_enable(struct dmcu *dmcu, bool enable, bool wait)
 				if (state == PSR_STATE0)
 					break;
 			}
-			fsleep(500);
+			/* must *not* be fsleep - this can be called from high irq levels */
+			udelay(500);
 		}
 
 		/* assert if max retry hit */
diff --git a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
index 0f24b6fbd22013a86ad8f516d256aa9c9e8643e4..4704c9c85ee6f5c964d353696a0b71b01cdbe933 100644
--- a/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
+++ b/drivers/gpu/drm/amd/display/dc/dce/dmub_psr.c
@@ -216,7 +216,8 @@ static void dmub_psr_enable(struct dmub_psr *dmub, bool enable, bool wait, uint8
 					break;
 			}
 
-			fsleep(500);
+			/* must *not* be fsleep - this can be called from high irq levels */
+			udelay(500);
 		}
 
 		/* assert if max retry hit */