qed: Protect the doorbell BAR with the write barriers.
SPQ doorbell is currently protected with the compilation barrier. Under the
stress scenarios, we may get into a state where (due to the weak ordering)
several ramrod doorbells were written to the BAR with an out-of-order
producer values. Need to change the barrier type to a write barrier to make
sure that the write buffer is flushed after each doorbell.
Signed-off-by: Sudarsana Reddy Kalluru <sudarsana.kalluru@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/qlogic/qed/qed_spq.c b/drivers/net/ethernet/qlogic/qed/qed_spq.c
index 67d9893..b122f60 100644
--- a/drivers/net/ethernet/qlogic/qed/qed_spq.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_spq.c
@@ -213,19 +213,15 @@
SET_FIELD(db.params, CORE_DB_DATA_AGG_VAL_SEL,
DQ_XCM_CORE_SPQ_PROD_CMD);
db.agg_flags = DQ_XCM_CORE_DQ_CF_CMD;
-
- /* validate producer is up to-date */
- rmb();
-
db.spq_prod = cpu_to_le16(qed_chain_get_prod_idx(p_chain));
- /* do not reorder */
- barrier();
+ /* make sure the SPQE is updated before the doorbell */
+ wmb();
DOORBELL(p_hwfn, qed_db_addr(p_spq->cid, DQ_DEMS_LEGACY), *(u32 *)&db);
/* make sure doorbell is rang */
- mmiowb();
+ wmb();
DP_VERBOSE(p_hwfn, QED_MSG_SPQ,
"Doorbelled [0x%08x, CID 0x%08x] with Flags: %02x agg_params: %02x, prod: %04x\n",