linux: mvebu: backport mvneta XDP support fixes

This patch backports additional fixes for XDP support in the mvneta driver. These
changes are found upstream as commits:

b37fa92e20ef2 net: mvneta: fix build skb for bm capable devices
f383b2950070c net: mvneta: rely on page_pool_recycle_direct in mvneta_run_xdp
79572c98c554d mvneta driver disallow XDP program on hardware buffer management
44efc78d0e464 net: mvneta: fix XDP support if sw bm is used as fallback

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

1 files changed, 67 insertions, 0 deletions

diff --git a/target/linux/mvebu/patches-5.4/023-net-mvneta-fix-XDP-support-if-sw-bm-is-used-as-fallb.patch b/target/linux/mvebu/patches-5.4/023-net-mvneta-fix-XDP-support-if-sw-bm-is-used-as-fallb.patch
new file mode 100644
index 0000000000..38b874cd49
--- /dev/null
+++ b/target/linux/mvebu/patches-5.4/023-net-mvneta-fix-XDP-support-if-sw-bm-is-used-as-fallb.patch
@@ -0,0 +1,67 @@
+From 44efc78d0e464ce70b45b165c005f8bedc17952e Mon Sep 17 00:00:00 2001
+From: Lorenzo Bianconi <lorenzo@kernel.org>
+Date: Wed, 29 Jan 2020 12:50:53 +0100
+Subject: [PATCH] net: mvneta: fix XDP support if sw bm is used as fallback
+
+In order to fix XDP support if sw buffer management is used as fallback
+for hw bm devices, define MVNETA_SKB_HEADROOM as maximum between
+XDP_PACKET_HEADROOM and NET_SKB_PAD and let the hw aligns the IP header
+to 4-byte boundary.
+Fix rx_offset_correction initialization if mvneta_bm_port_init fails in
+mvneta_resume routine
+
+Fixes: 0db51da7a8e9 ("net: mvneta: add basic XDP support")
+Tested-by: Sven Auhagen <sven.auhagen@voleatech.de>
+Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/ethernet/marvell/mvneta.c | 10 +++++++---
+ 1 file changed, 7 insertions(+), 3 deletions(-)
+
+--- a/drivers/net/ethernet/marvell/mvneta.c
++++ b/drivers/net/ethernet/marvell/mvneta.c
+@@ -324,8 +324,7 @@
+ 	      ETH_HLEN + ETH_FCS_LEN,			     \
+ 	      cache_line_size())
+ 
+-#define MVNETA_SKB_HEADROOM	(max(XDP_PACKET_HEADROOM, NET_SKB_PAD) + \
+-				 NET_IP_ALIGN)
++#define MVNETA_SKB_HEADROOM	max(XDP_PACKET_HEADROOM, NET_SKB_PAD)
+ #define MVNETA_SKB_PAD	(SKB_DATA_ALIGN(sizeof(struct skb_shared_info) + \
+ 			 MVNETA_SKB_HEADROOM))
+ #define MVNETA_SKB_SIZE(len)	(SKB_DATA_ALIGN(len) + MVNETA_SKB_PAD)
+@@ -1172,6 +1171,7 @@ bm_mtu_err:
+ 	mvneta_bm_pool_destroy(pp->bm_priv, pp->pool_short, 1 << pp->id);
+ 
+ 	pp->bm_priv = NULL;
++	pp->rx_offset_correction = MVNETA_SKB_HEADROOM;
+ 	mvreg_write(pp, MVNETA_ACC_MODE, MVNETA_ACC_MODE_EXT1);
+ 	netdev_info(pp->dev, "fail to update MTU, fall back to software BM\n");
+ }
+@@ -4954,7 +4954,6 @@ static int mvneta_probe(struct platform_
+ 	SET_NETDEV_DEV(dev, &pdev->dev);
+ 
+ 	pp->id = global_port_id++;
+-	pp->rx_offset_correction = MVNETA_SKB_HEADROOM;
+ 
+ 	/* Obtain access to BM resources if enabled and already initialized */
+ 	bm_node = of_parse_phandle(dn, "buffer-manager", 0);
+@@ -4979,6 +4978,10 @@ static int mvneta_probe(struct platform_
+ 	}
+ 	of_node_put(bm_node);
+ 
++	/* sw buffer management */
++	if (!pp->bm_priv)
++		pp->rx_offset_correction = MVNETA_SKB_HEADROOM;
++
+ 	err = mvneta_init(&pdev->dev, pp);
+ 	if (err < 0)
+ 		goto err_netdev;
+@@ -5136,6 +5139,7 @@ static int mvneta_resume(struct device *
+ 		err = mvneta_bm_port_init(pdev, pp);
+ 		if (err < 0) {
+ 			dev_info(&pdev->dev, "use SW buffer management\n");
++			pp->rx_offset_correction = MVNETA_SKB_HEADROOM;
+ 			pp->bm_priv = NULL;
+ 		}
+ 	}