diff --git a/drivers/edac/amd64_edac.c b/drivers/edac/amd64_edac.c
index 94265e438514..05d6f9c86ac3 100644
--- a/drivers/edac/amd64_edac.c
+++ b/drivers/edac/amd64_edac.c
@@ -2863,6 +2863,7 @@ 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;
 		}
 	}