WORKLOAD REPOSITORY report for database

use below query:

select output from table( dbms_workload_repository.awr_report_html
((select dbid from V$DATABASE),
(select INSTANCE_NUMBER from V$INSTANCE),
(select max(snap_id)-10 from dba_hist_snapshot),
(select max(snap_id) from dba_hist_snapshot),
0))

and after get result save as file.htm