[PATCH net-next v2 3/4] octeon_ep: implement xmit_more in transmit

[Shinas Rasheed <srasheed@marvell.com>]

Add xmit_more handling in tx datapath for octeon_ep pf.

Signed-off-by: Shinas Rasheed <srasheed@marvell.com>
---
V2:
  - Updated changelog to have imperative tone.
V1: https://lore.kernel.org/all/20231023114449.2362147-3-srasheed@marvell.com/

 .../ethernet/marvell/octeon_ep/octep_config.h |  2 +-
 .../ethernet/marvell/octeon_ep/octep_main.c   | 19 +++++++++++++++----
 2 files changed, 16 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_config.h b/drivers/net/ethernet/marvell/octeon_ep/octep_config.h
index 1622a6ebf036..ed8b1ace56b9 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_config.h
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_config.h
@@ -15,7 +15,7 @@
 /* Tx Queue: maximum descriptors per ring */
 #define OCTEP_IQ_MAX_DESCRIPTORS    1024
 /* Minimum input (Tx) requests to be enqueued to ring doorbell */
-#define OCTEP_DB_MIN                1
+#define OCTEP_DB_MIN                8
 /* Packet threshold for Tx queue interrupt */
 #define OCTEP_IQ_INTR_THRESHOLD     0x0
 
diff --git a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
index 1c02304677c9..1a88a6bf0598 100644
--- a/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
+++ b/drivers/net/ethernet/marvell/octeon_ep/octep_main.c
@@ -818,6 +818,7 @@ static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
 	struct octep_iq *iq;
 	skb_frag_t *frag;
 	u16 nr_frags, si;
+	int xmit_more;
 	u16 q_no, wi;
 
 	if (skb_put_padto(skb, ETH_ZLEN))
@@ -895,18 +896,28 @@ static netdev_tx_t octep_start_xmit(struct sk_buff *skb,
 	}
 
 	netdev_tx_sent_queue(iq->netdev_q, skb->len);
+
+	xmit_more = netdev_xmit_more();
+
 	skb_tx_timestamp(skb);
 	atomic_inc(&iq->instr_pending);
+	iq->fill_cnt++;
 	wi++;
 	if (wi == iq->max_count)
 		wi = 0;
 	iq->host_write_index = wi;
+	if (xmit_more &&
+	    (atomic_read(&iq->instr_pending) <
+	     (iq->max_count - OCTEP_WAKE_QUEUE_THRESHOLD)) &&
+	    iq->fill_cnt < iq->fill_threshold)
+		return NETDEV_TX_OK;
+
 	/* Flush the hw descriptor before writing to doorbell */
 	wmb();
-
-	/* Ring Doorbell to notify the NIC there is a new packet */
-	writel(1, iq->doorbell_reg);
-	iq->stats.instr_posted++;
+	/* Ring Doorbell to notify the NIC of new packets */
+	writel(iq->fill_cnt, iq->doorbell_reg);
+	iq->stats.instr_posted += iq->fill_cnt;
+	iq->fill_cnt = 0;
 	return NETDEV_TX_OK;
 
 dma_map_sg_err:
-- 
2.25.1