bnxt_en: Add ULP call to notify async events

When the driver receives an async event notification from the Firmware,
we make the new ulp_async_notifier() call to inform the RDMA driver that
a firmware async event has been received. RDMA driver can then take
necessary actions based on the event type.

In the next patch, we will implement the ulp_async_notifier() callbacks
in the RDMA driver.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Selvin Xavier <selvin.xavier@broadcom.com>
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Link: https://patch.msgid.link/20250107024553.2926983-2-kalesh-anakkur.purayil@broadcom.com
Signed-off-by: Leon Romanovsky <leon@kernel.org>

drivers/net/ethernet/broadcom/bnxt/bnxt.c

@@ -2857,6 +2857,7 @@ static int bnxt_async_event_process(struct bnxt *bp,
 	}
 	__bnxt_queue_sp_work(bp);
 async_event_process_exit:
+	bnxt_ulp_async_events(bp, cmpl);
 	return 0;
 }
 

drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.c

@@ -345,6 +345,34 @@ void bnxt_ulp_irq_restart(struct bnxt *bp, int err)
 	}
 }
 
+void bnxt_ulp_async_events(struct bnxt *bp, struct hwrm_async_event_cmpl *cmpl)
+{
+	u16 event_id = le16_to_cpu(cmpl->event_id);
+	struct bnxt_en_dev *edev = bp->edev;
+	struct bnxt_ulp_ops *ops;
+	struct bnxt_ulp *ulp;
+
+	if (!bnxt_ulp_registered(edev))
+		return;
+	ulp = edev->ulp_tbl;
+
+	rcu_read_lock();
+
+	ops = rcu_dereference(ulp->ulp_ops);
+	if (!ops || !ops->ulp_async_notifier)
+		goto exit_unlock_rcu;
+	if (!ulp->async_events_bmap || event_id > ulp->max_async_event_id)
+		goto exit_unlock_rcu;
+
+	/* Read max_async_event_id first before testing the bitmap. */
+	smp_rmb();
+
+	if (test_bit(event_id, ulp->async_events_bmap))
+		ops->ulp_async_notifier(ulp->handle, cmpl);
+exit_unlock_rcu:
+	rcu_read_unlock();
+}
+
 int bnxt_register_async_events(struct bnxt_en_dev *edev,
 			       unsigned long *events_bmap,
 			       u16 max_id)

drivers/net/ethernet/broadcom/bnxt/bnxt_ulp.h

@@ -30,6 +30,8 @@ struct bnxt_msix_entry {
 };
 
 struct bnxt_ulp_ops {
+	/* async_notifier() cannot sleep (in BH context) */
+	void (*ulp_async_notifier)(void *, struct hwrm_async_event_cmpl *);
 	void (*ulp_irq_stop)(void *);
 	void (*ulp_irq_restart)(void *, struct bnxt_msix_entry *);
 };