diff --git a/drivers/staging/gasket/gasket_page_table.c b/drivers/staging/gasket/gasket_page_table.c
index 779ad2f23ef9..8364b49f147c 100644
--- a/drivers/staging/gasket/gasket_page_table.c
+++ b/drivers/staging/gasket/gasket_page_table.c
@@ -562,7 +562,7 @@ static ulong gasket_extended_lvl0_page_idx(struct gasket_page_table *pg_tbl,
 					   ulong dev_addr)
 {
 	return (dev_addr >> GASKET_EXTENDED_LVL0_SHIFT) &
-	       ((1 << GASKET_EXTENDED_LVL0_WIDTH) - 1);
+		(pg_tbl->config.total_entries - 1);
 }
 
 /*