diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index c1d4536ae466e..cc5e56d752c8d 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2936,6 +2936,7 @@ static int init_csrows_df(struct mem_ctl_info *mci)
 			dimm->mtype = pvt->dram_type;
 			dimm->edac_mode = edac_mode;
 			dimm->dtype = dev_type;
+			dimm->grain = 64;
 		}
 	}
 
@@ -3012,6 +3013,7 @@ static int init_csrows(struct mem_ctl_info *mci)
 			dimm = csrow->channels[j]->dimm;
 			dimm->mtype = pvt->dram_type;
 			dimm->edac_mode = edac_mode;
+			dimm->grain = 64;
 		}
 	}