can: mcp251xfd: add BQL support

This patch adds BQL support to the driver. Support for netdev_xmit_more() will
be added in a separate patch series.

Link: https://lore.kernel.org/r/20210114153448.1506901-7-mkl@pengutronix.de
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

drivers/net/can/spi/mcp251xfd/mcp251xfd-core.c

@@ -335,6 +335,8 @@ static void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
 	u8 len;
 	int i, j;
 
+	netdev_reset_queue(priv->ndev);
+
 	/* TEF */
 	tef_ring = priv->tef;
 	tef_ring->head = 0;
@@ -1249,7 +1251,8 @@ mcp251xfd_handle_tefif_recover(const struct mcp251xfd_priv *priv, const u32 seq)
 
 static int
 mcp251xfd_handle_tefif_one(struct mcp251xfd_priv *priv,
-			   const struct mcp251xfd_hw_tef_obj *hw_tef_obj)
+			   const struct mcp251xfd_hw_tef_obj *hw_tef_obj,
+			   unsigned int *frame_len_ptr)
 {
 	struct net_device_stats *stats = &priv->ndev->stats;
 	u32 seq, seq_masked, tef_tail_masked;
@@ -1271,7 +1274,8 @@ mcp251xfd_handle_tefif_one(struct mcp251xfd_priv *priv,
 	stats->tx_bytes +=
 		can_rx_offload_get_echo_skb(&priv->offload,
 					    mcp251xfd_get_tef_tail(priv),
-					    hw_tef_obj->ts, NULL);
+					    hw_tef_obj->ts,
+					    frame_len_ptr);
 	stats->tx_packets++;
 	priv->tef->tail++;
 
@@ -1329,6 +1333,7 @@ mcp251xfd_tef_obj_read(const struct mcp251xfd_priv *priv,
 static int mcp251xfd_handle_tefif(struct mcp251xfd_priv *priv)
 {
 	struct mcp251xfd_hw_tef_obj hw_tef_obj[MCP251XFD_TX_OBJ_NUM_MAX];
+	unsigned int total_frame_len = 0;
 	u8 tef_tail, len, l;
 	int err, i;
 
@@ -1350,7 +1355,9 @@ static int mcp251xfd_handle_tefif(struct mcp251xfd_priv *priv)
 	}
 
 	for (i = 0; i < len; i++) {
-		err = mcp251xfd_handle_tefif_one(priv, &hw_tef_obj[i]);
+		unsigned int frame_len;
+
+		err = mcp251xfd_handle_tefif_one(priv, &hw_tef_obj[i], &frame_len);
 		/* -EAGAIN means the Sequence Number in the TEF
 		 * doesn't match our tef_tail. This can happen if we
 		 * read the TEF objects too early. Leave loop let the
@@ -1360,6 +1367,8 @@ static int mcp251xfd_handle_tefif(struct mcp251xfd_priv *priv)
 			goto out_netif_wake_queue;
 		if (err)
 			return err;
+
+		total_frame_len += frame_len;
 	}
 
  out_netif_wake_queue:
@@ -1390,6 +1399,7 @@ static int mcp251xfd_handle_tefif(struct mcp251xfd_priv *priv)
 			return err;
 
 		tx_ring->tail += len;
+		netdev_completed_queue(priv->ndev, len, total_frame_len);
 
 		err = mcp251xfd_check_tef_tail(priv);
 		if (err)
@@ -2435,6 +2445,7 @@ static netdev_tx_t mcp251xfd_start_xmit(struct sk_buff *skb,
 	struct mcp251xfd_priv *priv = netdev_priv(ndev);
 	struct mcp251xfd_tx_ring *tx_ring = priv->tx;
 	struct mcp251xfd_tx_obj *tx_obj;
+	unsigned int frame_len;
 	u8 tx_head;
 	int err;
 
@@ -2453,7 +2464,9 @@ static netdev_tx_t mcp251xfd_start_xmit(struct sk_buff *skb,
 	if (mcp251xfd_get_tx_free(tx_ring) == 0)
 		netif_stop_queue(ndev);
 
-	can_put_echo_skb(skb, ndev, tx_head, 0);
+	frame_len = can_skb_get_frame_len(skb);
+	can_put_echo_skb(skb, ndev, tx_head, frame_len);
+	netdev_sent_queue(priv->ndev, frame_len);
 
 	err = mcp251xfd_tx_obj_write(priv, tx_obj);
 	if (err)