linux: mvebu: backport mvneta XDP support

This patch backports XDP support in the mvneta driver used by Marvell ARMADA 37x,
38x and 37xx series SoCs. Supported actions are:

- XDP_DROP
- XDP_PASS
- XDP_REDIRECT
- XDP_TX

Patches are present upstream as following commits:

* b0a43db9087a net: mvneta: add XDP_TX support
* 9e58c8b41065 net: mvneta: make tx buffer array agnostic
* fa383f6b77a2 net: mvneta: move header prefetch in mvneta_swbm_rx_frame
* 0db51da7a8e9 net: mvneta: add basic XDP support
* 8dc9a0888f4c net: mvneta: rely on build_skb in mvneta_rx_swbm poll routine
* 568a3fa24a95 net: mvneta: introduce page pool API for sw buffer manager
* ff519e2acd46 net: mvneta: introduce mvneta_update_stats routine

Signed-off-by: Jakov Petrina <jakov.petrina@sartura.hr>

1 files changed, 210 insertions, 0 deletions

diff --git a/target/linux/mvebu/patches-5.4/015-net-mvneta-make-tx-buffer-array-agnostic.patch b/target/linux/mvebu/patches-5.4/015-net-mvneta-make-tx-buffer-array-agnostic.patch
new file mode 100644
index 0000000000..d44a3f1a49
--- /dev/null
+++ b/target/linux/mvebu/patches-5.4/015-net-mvneta-make-tx-buffer-array-agnostic.patch
@@ -0,0 +1,210 @@
+From f7f705a63cd4bd1e3463db7662011717c5149e8a Mon Sep 17 00:00:00 2001
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Sat, 19 Oct 2019 10:13:26 +0200
+Subject: [PATCH 6/7] net: mvneta: make tx buffer array agnostic
+
+Allow tx buffer array to contain both skb and xdp buffers in order to
+enable xdp frame recycling adding XDP_TX verdict support
+
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/marvell/mvneta.c | 66 +++++++++++++++++----------
+ 1 file changed, 43 insertions(+), 23 deletions(-)
+
+--- a/drivers/net/ethernet/marvell/mvneta.c
++++ b/drivers/net/ethernet/marvell/mvneta.c
+@@ -563,6 +563,20 @@ struct mvneta_rx_desc {
+ };
+ #endif
+ 
++enum mvneta_tx_buf_type {
++	MVNETA_TYPE_SKB,
++	MVNETA_TYPE_XDP_TX,
++	MVNETA_TYPE_XDP_NDO,
++};
++
++struct mvneta_tx_buf {
++	enum mvneta_tx_buf_type type;
++	union {
++		struct xdp_frame *xdpf;
++		struct sk_buff *skb;
++	};
++};
++
+ struct mvneta_tx_queue {
+ 	/* Number of this TX queue, in the range 0-7 */
+ 	u8 id;
+@@ -578,8 +592,8 @@ struct mvneta_tx_queue {
+ 	int tx_stop_threshold;
+ 	int tx_wake_threshold;
+ 
+-	/* Array of transmitted skb */
+-	struct sk_buff **tx_skb;
++	/* Array of transmitted buffers */
++	struct mvneta_tx_buf *buf;
+ 
+ 	/* Index of last TX DMA descriptor that was inserted */
+ 	int txq_put_index;
+@@ -1791,14 +1805,9 @@ static void mvneta_txq_bufs_free(struct
+ 	int i;
+ 
+ 	for (i = 0; i < num; i++) {
++		struct mvneta_tx_buf *buf = &txq->buf[txq->txq_get_index];
+ 		struct mvneta_tx_desc *tx_desc = txq->descs +
+ 			txq->txq_get_index;
+-		struct sk_buff *skb = txq->tx_skb[txq->txq_get_index];
+-
+-		if (skb) {
+-			bytes_compl += skb->len;
+-			pkts_compl++;
+-		}
+ 
+ 		mvneta_txq_inc_get(txq);
+ 
+@@ -1806,9 +1815,12 @@ static void mvneta_txq_bufs_free(struct
+ 			dma_unmap_single(pp->dev->dev.parent,
+ 					 tx_desc->buf_phys_addr,
+ 					 tx_desc->data_size, DMA_TO_DEVICE);
+-		if (!skb)
++		if (!buf->skb)
+ 			continue;
+-		dev_kfree_skb_any(skb);
++
++		bytes_compl += buf->skb->len;
++		pkts_compl++;
++		dev_kfree_skb_any(buf->skb);
+ 	}
+ 
+ 	netdev_tx_completed_queue(nq, pkts_compl, bytes_compl);
+@@ -2333,16 +2345,19 @@ static inline void
+ mvneta_tso_put_hdr(struct sk_buff *skb,
+ 		   struct mvneta_port *pp, struct mvneta_tx_queue *txq)
+ {
+-	struct mvneta_tx_desc *tx_desc;
+ 	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
++	struct mvneta_tx_buf *buf = &txq->buf[txq->txq_put_index];
++	struct mvneta_tx_desc *tx_desc;
+ 
+-	txq->tx_skb[txq->txq_put_index] = NULL;
+ 	tx_desc = mvneta_txq_next_desc_get(txq);
+ 	tx_desc->data_size = hdr_len;
+ 	tx_desc->command = mvneta_skb_tx_csum(pp, skb);
+ 	tx_desc->command |= MVNETA_TXD_F_DESC;
+ 	tx_desc->buf_phys_addr = txq->tso_hdrs_phys +
+ 				 txq->txq_put_index * TSO_HEADER_SIZE;
++	buf->type = MVNETA_TYPE_SKB;
++	buf->skb = NULL;
++
+ 	mvneta_txq_inc_put(txq);
+ }
+ 
+@@ -2351,6 +2366,7 @@ mvneta_tso_put_data(struct net_device *d
+ 		    struct sk_buff *skb, char *data, int size,
+ 		    bool last_tcp, bool is_last)
+ {
++	struct mvneta_tx_buf *buf = &txq->buf[txq->txq_put_index];
+ 	struct mvneta_tx_desc *tx_desc;
+ 
+ 	tx_desc = mvneta_txq_next_desc_get(txq);
+@@ -2364,7 +2380,8 @@ mvneta_tso_put_data(struct net_device *d
+ 	}
+ 
+ 	tx_desc->command = 0;
+-	txq->tx_skb[txq->txq_put_index] = NULL;
++	buf->type = MVNETA_TYPE_SKB;
++	buf->skb = NULL;
+ 
+ 	if (last_tcp) {
+ 		/* last descriptor in the TCP packet */
+@@ -2372,7 +2389,7 @@ mvneta_tso_put_data(struct net_device *d
+ 
+ 		/* last descriptor in SKB */
+ 		if (is_last)
+-			txq->tx_skb[txq->txq_put_index] = skb;
++			buf->skb = skb;
+ 	}
+ 	mvneta_txq_inc_put(txq);
+ 	return 0;
+@@ -2457,6 +2474,7 @@ static int mvneta_tx_frag_process(struct
+ 	int i, nr_frags = skb_shinfo(skb)->nr_frags;
+ 
+ 	for (i = 0; i < nr_frags; i++) {
++		struct mvneta_tx_buf *buf = &txq->buf[txq->txq_put_index];
+ 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+ 		void *addr = skb_frag_address(frag);
+ 
+@@ -2476,12 +2494,13 @@ static int mvneta_tx_frag_process(struct
+ 		if (i == nr_frags - 1) {
+ 			/* Last descriptor */
+ 			tx_desc->command = MVNETA_TXD_L_DESC | MVNETA_TXD_Z_PAD;
+-			txq->tx_skb[txq->txq_put_index] = skb;
++			buf->skb = skb;
+ 		} else {
+ 			/* Descriptor in the middle: Not First, Not Last */
+ 			tx_desc->command = 0;
+-			txq->tx_skb[txq->txq_put_index] = NULL;
++			buf->skb = NULL;
+ 		}
++		buf->type = MVNETA_TYPE_SKB;
+ 		mvneta_txq_inc_put(txq);
+ 	}
+ 
+@@ -2509,6 +2528,7 @@ static netdev_tx_t mvneta_tx(struct sk_b
+ 	struct mvneta_port *pp = netdev_priv(dev);
+ 	u16 txq_id = skb_get_queue_mapping(skb);
+ 	struct mvneta_tx_queue *txq = &pp->txqs[txq_id];
++	struct mvneta_tx_buf *buf = &txq->buf[txq->txq_put_index];
+ 	struct mvneta_tx_desc *tx_desc;
+ 	int len = skb->len;
+ 	int frags = 0;
+@@ -2541,16 +2561,17 @@ static netdev_tx_t mvneta_tx(struct sk_b
+ 		goto out;
+ 	}
+ 
++	buf->type = MVNETA_TYPE_SKB;
+ 	if (frags == 1) {
+ 		/* First and Last descriptor */
+ 		tx_cmd |= MVNETA_TXD_FLZ_DESC;
+ 		tx_desc->command = tx_cmd;
+-		txq->tx_skb[txq->txq_put_index] = skb;
++		buf->skb = skb;
+ 		mvneta_txq_inc_put(txq);
+ 	} else {
+ 		/* First but not Last */
+ 		tx_cmd |= MVNETA_TXD_F_DESC;
+-		txq->tx_skb[txq->txq_put_index] = NULL;
++		buf->skb = NULL;
+ 		mvneta_txq_inc_put(txq);
+ 		tx_desc->command = tx_cmd;
+ 		/* Continue with other skb fragments */
+@@ -3136,9 +3157,8 @@ static int mvneta_txq_sw_init(struct mvn
+ 
+ 	txq->last_desc = txq->size - 1;
+ 
+-	txq->tx_skb = kmalloc_array(txq->size, sizeof(*txq->tx_skb),
+-				    GFP_KERNEL);
+-	if (!txq->tx_skb) {
++	txq->buf = kmalloc_array(txq->size, sizeof(*txq->buf), GFP_KERNEL);
++	if (!txq->buf) {
+ 		dma_free_coherent(pp->dev->dev.parent,
+ 				  txq->size * MVNETA_DESC_ALIGNED_SIZE,
+ 				  txq->descs, txq->descs_phys);
+@@ -3150,7 +3170,7 @@ static int mvneta_txq_sw_init(struct mvn
+ 					   txq->size * TSO_HEADER_SIZE,
+ 					   &txq->tso_hdrs_phys, GFP_KERNEL);
+ 	if (!txq->tso_hdrs) {
+-		kfree(txq->tx_skb);
++		kfree(txq->buf);
+ 		dma_free_coherent(pp->dev->dev.parent,
+ 				  txq->size * MVNETA_DESC_ALIGNED_SIZE,
+ 				  txq->descs, txq->descs_phys);
+@@ -3203,7 +3223,7 @@ static void mvneta_txq_sw_deinit(struct
+ {
+ 	struct netdev_queue *nq = netdev_get_tx_queue(pp->dev, txq->id);
+ 
+-	kfree(txq->tx_skb);
++	kfree(txq->buf);
+ 
+ 	if (txq->tso_hdrs)
+ 		dma_free_coherent(pp->dev->dev.parent,