FCOE_DB_DATA_AGG_VAL_SEL_SHIFT;
dbell.sq_prod = fcport->fw_sq_prod_idx;
+ /* wmb makes sure that the BDs data is updated before updating the
+ * producer, otherwise FW may read old data from the BDs.
+ */
+ wmb();
+ barrier();
writel(*(u32 *)&dbell, fcport->p_doorbell);
- /* Make sure SQ index is updated so f/w prcesses requests in order */
+ /*
+ * Fence required to flush the write combined buffer, since another
+ * CPU may write to the same doorbell address and data may be lost
+ * due to relaxed order nature of write combined bar.
+ */
wmb();
- mmiowb();
}
static void qedf_trace_io(struct qedf_rport *fcport, struct qedf_ioreq *io_req,