[PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[Roger Quadros]

This series adds AF_XDP zero coppy support to am65-cpsw driver.

Tests were performed on AM62x-sk with xdpsock application [1].

A clear improvement is seen in 64 byte packets on Transmit (txonly)
and receive (rxdrop).
1500 byte test seems to be limited by line rate (1G link) so no
improvement seen there in packet rate. A test on higher speed link
(or PHY-less setup) might be worthwile.

There is some issue during l2fwd with 64 byte packets and benchmark
results show 0. This issue needs to be debugged further.
A 512 byte l2fwd test result has been added to compare instead.

AF_XDP performance using 64 byte packets in Kpps.
Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
rxdrop		322		491		845
txonly		390		394		723
l2fwd 		205		257		0

AF_XDP performance using 512 byte packets in Kpps.
l2fwd		140		167		231

AF_XDP performance using 1500 byte packets in Kpps.
Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
rxdrop		82		82		82
txonly		82		82		82
l2fwd 		82		82		82

[1]: https://github.com/xdp-project/bpf-examples/tree/master/AF_XDP-example

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
Changes in v2:
- Prevent crash on systems with 1 of 2 ports disabled in device tree. check
  for valid ndev before registering/unregistering XDP RXQ.
  Reported-by: Meghana Malladi <m-malladi@ti.com>
- Retain page pool on XDP program exchangae so we don't have to re-alloacate
  memory.
- Fix clearing of irq_disabled flag in am65_cpsw_nuss_rx_poll().
- Link to v1: https://lore.kernel.org/r/20250520-am65-cpsw-xdp-zc-v1-0-45558024f566@kernel.org

---
Roger Quadros (7):
      net: ethernet: ti: am65-cpsw: fix BPF Program change on multi-port CPSW
      net: ethernet: ti: am65-cpsw: Retain page_pool on XDP program exchange
      net: ethernet: ti: am65-cpsw: add XSK pool helpers
      net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for RX
      net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for TX
      net: ethernet: ti: am65-cpsw: enable zero copy in XDP features
      net: ethernet: ti: am65-cpsw: Fix clearing of irq_disabled flag in rx_poll

 drivers/net/ethernet/ti/Makefile         |   2 +-
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 583 ++++++++++++++++++++++++++-----
 drivers/net/ethernet/ti/am65-cpsw-nuss.h |  37 +-
 drivers/net/ethernet/ti/am65-cpsw-xdp.c  | 155 ++++++++
 4 files changed, 692 insertions(+), 85 deletions(-)
---
base-commit: a0c3aefb08cd81864b17c23c25b388dba90b9dad
change-id: 20250225-am65-cpsw-xdp-zc-2af9e4be1356

Best regards,
-- 
Roger Quadros <rogerq@kernel.org>

[PATCH net-next v2 1/7] net: ethernet: ti: am65-cpsw: fix BPF Program change on multi-port CPSW

[Roger Quadros]

On a multi-port CPSW system, stopping and starting just one port (ndev)
will not restart the queues if other ports (ndevs) are open.

Instead, check the usage_count variable to know if CPSW is running
and if so restart all the queues.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 25 ++++++++++++++++++++-----
 1 file changed, 20 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index d5f358ec982050751a63039e73887bf6e7f684e7..f8beb1735fb9cb75577e60f5b22111cb3a66acb9 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -1919,18 +1919,33 @@ static int am65_cpsw_xdp_prog_setup(struct net_device *ndev,
 				    struct bpf_prog *prog)
 {
 	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
-	bool running = netif_running(ndev);
+	struct am65_cpsw_common *common = port->common;
+	bool running = !!port->common->usage_count;
 	struct bpf_prog *old_prog;
+	int ret;
 
-	if (running)
-		am65_cpsw_nuss_ndo_slave_stop(ndev);
+	if (running) {
+		/* stop all queues */
+		am65_cpsw_destroy_txqs(common);
+		am65_cpsw_destroy_rxqs(common);
+	}
 
 	old_prog = xchg(&port->xdp_prog, prog);
 	if (old_prog)
 		bpf_prog_put(old_prog);
 
-	if (running)
-		return am65_cpsw_nuss_ndo_slave_open(ndev);
+	if (running) {
+		/* start all queues */
+		ret = am65_cpsw_create_rxqs(common);
+		if (ret)
+			return ret;
+
+		ret = am65_cpsw_create_txqs(common);
+		if (ret) {
+			am65_cpsw_destroy_rxqs(common);
+			return ret;
+		}
+	}
 
 	return 0;
 }

-- 
2.34.1

[PATCH net-next v2 2/7] net: ethernet: ti: am65-cpsw: Retain page_pool on XDP program exchange

[Roger Quadros]

Add a new 'retain_page_pool' flag to am65_cpsw_destroy_rxq/s()
so that the page pool allocation is retained  while
switching XDP program. This will avoid requiring
any re-allocation and potential failures during low memory
conditions.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 38 ++++++++++++++++++--------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index f8beb1735fb9cb75577e60f5b22111cb3a66acb9..f9e2286efa29bbb7056fda1fc82c38b479aae8bd 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -505,7 +505,7 @@ static inline void am65_cpsw_put_page(struct am65_cpsw_rx_flow *flow,
 static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma);
 static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma);
 
-static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id)
+static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool)
 {
 	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
 	struct am65_cpsw_rx_flow *flow;
@@ -528,13 +528,13 @@ static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id)
 			xdp_rxq_info_unreg(rxq);
 	}
 
-	if (flow->page_pool) {
+	if (flow->page_pool && !retain_page_pool) {
 		page_pool_destroy(flow->page_pool);
 		flow->page_pool = NULL;
 	}
 }
 
-static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common)
+static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common, bool retain_page_pool)
 {
 	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
 	int id;
@@ -549,7 +549,7 @@ static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common)
 	}
 
 	for (id = common->rx_ch_num_flows - 1; id >= 0; id--)
-		am65_cpsw_destroy_rxq(common, id);
+		am65_cpsw_destroy_rxq(common, id, retain_page_pool);
 
 	k3_udma_glue_disable_rx_chn(common->rx_chns.rx_chn);
 }
@@ -574,13 +574,18 @@ static int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 
 	flow = &rx_chn->flows[id];
 	pp_params.napi = &flow->napi_rx;
-	pool = page_pool_create(&pp_params);
-	if (IS_ERR(pool)) {
-		ret = PTR_ERR(pool);
-		return ret;
-	}
 
-	flow->page_pool = pool;
+	if (!flow->page_pool) {
+		pool = page_pool_create(&pp_params);
+		if (IS_ERR(pool)) {
+			ret = PTR_ERR(pool);
+			return ret;
+		}
+
+		flow->page_pool = pool;
+	} else {
+		pool = flow->page_pool;
+	}
 
 	/* using same page pool is allowed as no running rx handlers
 	 * simultaneously for both ndevs
@@ -626,7 +631,7 @@ static int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 	return 0;
 
 err:
-	am65_cpsw_destroy_rxq(common, id);
+	am65_cpsw_destroy_rxq(common, id, false);
 	return ret;
 }
 
@@ -653,7 +658,7 @@ static int am65_cpsw_create_rxqs(struct am65_cpsw_common *common)
 
 err:
 	for (--id; id >= 0; id--)
-		am65_cpsw_destroy_rxq(common, id);
+		am65_cpsw_destroy_rxq(common, id, false);
 
 	return ret;
 }
@@ -942,7 +947,7 @@ static int am65_cpsw_nuss_common_open(struct am65_cpsw_common *common)
 	return 0;
 
 cleanup_rx:
-	am65_cpsw_destroy_rxqs(common);
+	am65_cpsw_destroy_rxqs(common, false);
 
 	return ret;
 }
@@ -956,7 +961,7 @@ static int am65_cpsw_nuss_common_stop(struct am65_cpsw_common *common)
 			     ALE_PORT_STATE, ALE_PORT_STATE_DISABLE);
 
 	am65_cpsw_destroy_txqs(common);
-	am65_cpsw_destroy_rxqs(common);
+	am65_cpsw_destroy_rxqs(common, false);
 	cpsw_ale_stop(common->ale);
 
 	writel(0, common->cpsw_base + AM65_CPSW_REG_CTL);
@@ -1927,7 +1932,8 @@ static int am65_cpsw_xdp_prog_setup(struct net_device *ndev,
 	if (running) {
 		/* stop all queues */
 		am65_cpsw_destroy_txqs(common);
-		am65_cpsw_destroy_rxqs(common);
+		/* Retain page pool */
+		am65_cpsw_destroy_rxqs(common, true);
 	}
 
 	old_prog = xchg(&port->xdp_prog, prog);
@@ -1942,7 +1948,7 @@ static int am65_cpsw_xdp_prog_setup(struct net_device *ndev,
 
 		ret = am65_cpsw_create_txqs(common);
 		if (ret) {
-			am65_cpsw_destroy_rxqs(common);
+			am65_cpsw_destroy_rxqs(common, false);
 			return ret;
 		}
 	}

-- 
2.34.1

[PATCH net-next v2 3/7] net: ethernet: ti: am65-cpsw: add XSK pool helpers

[Roger Quadros]

To prepare for XSK zero copy support, add XSK pool
helpers in a new file am65-cpsw-xdp.c

As queues are shared between ports we can no longer
support the case where zero copy (XSK Pool) is enabled
for the queue on one port but not for other ports.

Current solution is to drop the packet if Zero copy
is not enabled for that port + queue but enabled for
some other port + same queue.

xdp_zc_queues bitmap tracks if queue is setup as XSK
pool and xsk_port_id array tracks which port the XSK
queue is assigned to for zero copy.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/Makefile         |   2 +-
 drivers/net/ethernet/ti/am65-cpsw-nuss.c |  21 ++++--
 drivers/net/ethernet/ti/am65-cpsw-nuss.h |  20 +++++
 drivers/net/ethernet/ti/am65-cpsw-xdp.c  | 122 +++++++++++++++++++++++++++++++
 4 files changed, 156 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
index 93c0a4d0e33a6fb725ad61c3ec0eab87d2d3f61a..96585a28fc7d73f61b888e5d1587d5123875db31 100644
--- a/drivers/net/ethernet/ti/Makefile
+++ b/drivers/net/ethernet/ti/Makefile
@@ -29,7 +29,7 @@ keystone_netcp_ethss-y := netcp_ethss.o netcp_sgmii.o netcp_xgbepcsr.o cpsw_ale.
 obj-$(CONFIG_TI_K3_CPPI_DESC_POOL) += k3-cppi-desc-pool.o
 
 obj-$(CONFIG_TI_K3_AM65_CPSW_NUSS) += ti-am65-cpsw-nuss.o
-ti-am65-cpsw-nuss-y := am65-cpsw-nuss.o cpsw_sl.o am65-cpsw-ethtool.o cpsw_ale.o
+ti-am65-cpsw-nuss-y := am65-cpsw-nuss.o cpsw_sl.o am65-cpsw-ethtool.o cpsw_ale.o am65-cpsw-xdp.o
 ti-am65-cpsw-nuss-$(CONFIG_TI_AM65_CPSW_QOS) += am65-cpsw-qos.o
 ti-am65-cpsw-nuss-$(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV) += am65-cpsw-switchdev.o
 obj-$(CONFIG_TI_K3_AM65_CPTS) += am65-cpts.o
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index f9e2286efa29bbb7056fda1fc82c38b479aae8bd..46523be93df27710be77b288c36c1a0f66d8ca8d 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -58,9 +58,6 @@
 
 #define AM65_CPSW_MAX_PORTS	8
 
-#define AM65_CPSW_MIN_PACKET_SIZE	VLAN_ETH_ZLEN
-#define AM65_CPSW_MAX_PACKET_SIZE	2024
-
 #define AM65_CPSW_REG_CTL		0x004
 #define AM65_CPSW_REG_STAT_PORT_EN	0x014
 #define AM65_CPSW_REG_PTYPE		0x018
@@ -505,7 +502,7 @@ static inline void am65_cpsw_put_page(struct am65_cpsw_rx_flow *flow,
 static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma);
 static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma);
 
-static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool)
+void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool)
 {
 	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
 	struct am65_cpsw_rx_flow *flow;
@@ -554,7 +551,7 @@ static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common, bool retain_
 	k3_udma_glue_disable_rx_chn(common->rx_chns.rx_chn);
 }
 
-static int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
+int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 {
 	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
 	struct page_pool_params pp_params = {
@@ -663,7 +660,7 @@ static int am65_cpsw_create_rxqs(struct am65_cpsw_common *common)
 	return ret;
 }
 
-static void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
+void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
 {
 	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
 
@@ -697,7 +694,7 @@ static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
 		am65_cpsw_destroy_txq(common, id);
 }
 
-static int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
+int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
 {
 	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
 	int ret;
@@ -1327,7 +1324,7 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
 	dma_unmap_single(rx_chn->dma_dev, buf_dma, buf_dma_len, DMA_FROM_DEVICE);
 	k3_cppi_desc_pool_free(rx_chn->desc_pool, desc_rx);
 
-	if (port->xdp_prog) {
+	if (am65_cpsw_xdp_is_enabled(port)) {
 		xdp_init_buff(&xdp, PAGE_SIZE, &port->xdp_rxq[flow->id]);
 		xdp_prepare_buff(&xdp, page_addr, AM65_CPSW_HEADROOM,
 				 pkt_len, false);
@@ -1961,6 +1958,9 @@ static int am65_cpsw_ndo_bpf(struct net_device *ndev, struct netdev_bpf *bpf)
 	switch (bpf->command) {
 	case XDP_SETUP_PROG:
 		return am65_cpsw_xdp_prog_setup(ndev, bpf->prog);
+	case XDP_SETUP_XSK_POOL:
+		return am65_cpsw_xsk_setup_pool(ndev, bpf->xsk.pool,
+						bpf->xsk.queue_id);
 	default:
 		return -EINVAL;
 	}
@@ -3553,7 +3553,12 @@ static int am65_cpsw_nuss_probe(struct platform_device *pdev)
 	common = devm_kzalloc(dev, sizeof(struct am65_cpsw_common), GFP_KERNEL);
 	if (!common)
 		return -ENOMEM;
+
 	common->dev = dev;
+	common->xdp_zc_queues = devm_bitmap_zalloc(dev, AM65_CPSW_MAX_QUEUES,
+						   GFP_KERNEL);
+	if (!common->xdp_zc_queues)
+		return -ENOMEM;
 
 	of_id = of_match_device(am65_cpsw_nuss_of_mtable, dev);
 	if (!of_id)
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.h b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
index 917c37e4e89bd933d3001f6c35a62db01cd8da4c..31789b5e5e1fc96be20cce17234d0e16cdcea796 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
@@ -23,8 +23,14 @@ struct am65_cpts;
 
 #define AM65_CPSW_MAX_QUEUES	8	/* both TX & RX */
 
+#define AM65_CPSW_MIN_PACKET_SIZE	VLAN_ETH_ZLEN
+#define AM65_CPSW_MAX_PACKET_SIZE	2024
+
 #define AM65_CPSW_PORT_VLAN_REG_OFFSET	0x014
 
+#define AM65_CPSW_RX_DMA_ATTR	(DMA_ATTR_SKIP_CPU_SYNC |\
+				 DMA_ATTR_WEAK_ORDERING)
+
 struct am65_cpsw_slave_data {
 	bool				mac_only;
 	struct cpsw_sl			*mac_sl;
@@ -190,6 +196,9 @@ struct am65_cpsw_common {
 	unsigned char switch_id[MAX_PHYS_ITEM_ID_LEN];
 	/* only for suspend/resume context restore */
 	u32			*ale_context;
+	/* XDP Zero Copy */
+	unsigned long		*xdp_zc_queues;
+	int			xsk_port_id[AM65_CPSW_MAX_QUEUES];
 };
 
 struct am65_cpsw_ndev_priv {
@@ -228,4 +237,15 @@ int am65_cpsw_nuss_update_tx_rx_chns(struct am65_cpsw_common *common,
 
 bool am65_cpsw_port_dev_check(const struct net_device *dev);
 
+int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id);
+void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool);
+int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id);
+void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id);
+int am65_cpsw_xsk_setup_pool(struct net_device *ndev,
+			     struct xsk_buff_pool *pool, u16 qid);
+int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags);
+static inline bool am65_cpsw_xdp_is_enabled(struct am65_cpsw_port *port)
+{
+	return !!READ_ONCE(port->xdp_prog);
+}
 #endif /* AM65_CPSW_NUSS_H_ */
diff --git a/drivers/net/ethernet/ti/am65-cpsw-xdp.c b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
new file mode 100644
index 0000000000000000000000000000000000000000..89f43f7c83db35dba96621bae930172e0fc85b6a
--- /dev/null
+++ b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Texas Instruments K3 AM65 Ethernet Switch SubSystem Driver
+ *
+ * Copyright (C) 2025 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ */
+
+#include <net/xsk_buff_pool.h>
+#include <net/xdp_sock_drv.h>
+#include "am65-cpsw-nuss.h"
+
+static int am65_cpsw_xsk_pool_enable(struct am65_cpsw_port *port,
+				     struct xsk_buff_pool *pool, u16 qid)
+{
+	struct am65_cpsw_common *common = port->common;
+	struct am65_cpsw_rx_chn *rx_chn;
+	bool need_update;
+	u32 frame_size;
+	int ret;
+
+	/*
+	 * As queues are shared between ports we can no longer
+	 * support the case where zero copy (XSK Pool) is enabled
+	 * for the queue on one port but not for other ports.
+	 *
+	 * Current solution is to drop the packet if Zero copy
+	 * is not enabled for that port + queue but enabled for
+	 * some other port + same queue.
+	 */
+	if (test_bit(qid, common->xdp_zc_queues))
+		return -EINVAL;
+
+	rx_chn = &common->rx_chns;
+	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
+		return -EINVAL;
+
+	frame_size = xsk_pool_get_rx_frame_size(pool);
+	if (frame_size < AM65_CPSW_MAX_PACKET_SIZE)
+		return -EOPNOTSUPP;
+
+	ret = xsk_pool_dma_map(pool, rx_chn->dma_dev, AM65_CPSW_RX_DMA_ATTR);
+	if (ret) {
+		netdev_err(port->ndev, "Failed to map xsk pool\n");
+		return ret;
+	}
+
+	need_update = common->usage_count &&
+		      am65_cpsw_xdp_is_enabled(port);
+	if (need_update) {
+		am65_cpsw_destroy_rxq(common, qid, true);
+		am65_cpsw_destroy_txq(common, qid);
+	}
+
+	set_bit(qid, common->xdp_zc_queues);
+	common->xsk_port_id[qid] = port->port_id;
+	if (need_update) {
+		am65_cpsw_create_rxq(common, qid);
+		am65_cpsw_create_txq(common, qid);
+	}
+
+	return 0;
+}
+
+static int am65_cpsw_xsk_pool_disable(struct am65_cpsw_port *port,
+				      struct xsk_buff_pool *pool, u16 qid)
+{
+	struct am65_cpsw_common *common = port->common;
+	bool need_update;
+
+	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
+		return -EINVAL;
+
+	if (!test_bit(qid, common->xdp_zc_queues))
+		return -EINVAL;
+
+	pool = xsk_get_pool_from_qid(port->ndev, qid);
+	if (!pool)
+		return -EINVAL;
+
+	need_update = common->usage_count && am65_cpsw_xdp_is_enabled(port);
+	if (need_update) {
+		am65_cpsw_destroy_rxq(common, qid, true);
+		am65_cpsw_destroy_txq(common, qid);
+		synchronize_rcu();
+	}
+
+	xsk_pool_dma_unmap(pool, AM65_CPSW_RX_DMA_ATTR);
+	clear_bit(qid, common->xdp_zc_queues);
+	common->xsk_port_id[qid] = -EINVAL;
+	if (need_update) {
+		am65_cpsw_create_rxq(common, qid);
+		am65_cpsw_create_txq(common, qid);
+	}
+
+	return 0;
+}
+
+int am65_cpsw_xsk_setup_pool(struct net_device *ndev,
+			     struct xsk_buff_pool *pool, u16 qid)
+{
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+
+	return pool ? am65_cpsw_xsk_pool_enable(port, pool, qid) :
+		      am65_cpsw_xsk_pool_disable(port, pool, qid);
+}
+
+int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
+{
+	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+
+	if (!netif_running(ndev) || !netif_carrier_ok(ndev))
+		return -ENETDOWN;
+
+	if (!am65_cpsw_xdp_is_enabled(port))
+		return -EINVAL;
+
+	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
+		return -EINVAL;
+
+	return 0;
+}

-- 
2.34.1

Re: [PATCH net-next v2 3/7] net: ethernet: ti: am65-cpsw: add XSK pool helpers

[Qiu, Daolin]

Hi Roger,

On 11/9/2025 3:37 PM, Roger Quadros wrote:
> To prepare for XSK zero copy support, add XSK pool
> helpers in a new file am65-cpsw-xdp.c
>
> As queues are shared between ports we can no longer
> support the case where zero copy (XSK Pool) is enabled
> for the queue on one port but not for other ports.
>
> Current solution is to drop the packet if Zero copy
> is not enabled for that port + queue but enabled for
> some other port + same queue.

I've been evaluating a use-case where one CPSW port is using XDP zero 
copy to pass EtherCAT frames to and from the userspace. The other CPSW 
port is a non-XDP zero copy port is used for connection to another PC 
running an IDE to monitor and configure the EtherCAT userspace 
application on the AM62x EVM.

According to the design described in this patch, I'm no longer able to 
connect to the IDE when the EtherCAT port is set up for XDP zero copy. 
Beyond just this use-case, there might be plenty of other use-cases 
where both non-XDP zero copy ports and XDP zero copy enabled ports need 
to be simultaneously used.

For this reason, I think there should be some change implemented so that 
the traffic on the non-XDP zero copy port does not get dropped. Is there 
a way to workaround the CPSW hardware limitation (shared queues between 
ports)?

One idea I was thinking is to configure multiple rx flows (enabled by 
the patch series in 
https://lore.kernel.org/all/20250514-am65-cpsw-rx-class-v4-0-5202d8119241@kernel.org/) 
and perhaps map each flow to a particular port? Since these rx flows 
aren't true hardware queues, I don't know if that would not be possible 
with the way XDP zero copy uses queues.

Please let me know what you think.

>
> xdp_zc_queues bitmap tracks if queue is setup as XSK
> pool and xsk_port_id array tracks which port the XSK
> queue is assigned to for zero copy.
>
> Signed-off-by: Roger Quadros <rogerq@kernel.org>
> ---
>   drivers/net/ethernet/ti/Makefile         |   2 +-
>   drivers/net/ethernet/ti/am65-cpsw-nuss.c |  21 ++++--
>   drivers/net/ethernet/ti/am65-cpsw-nuss.h |  20 +++++
>   drivers/net/ethernet/ti/am65-cpsw-xdp.c  | 122 +++++++++++++++++++++++++++++++
>   4 files changed, 156 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/ethernet/ti/Makefile b/drivers/net/ethernet/ti/Makefile
> index 93c0a4d0e33a6fb725ad61c3ec0eab87d2d3f61a..96585a28fc7d73f61b888e5d1587d5123875db31 100644
> --- a/drivers/net/ethernet/ti/Makefile
> +++ b/drivers/net/ethernet/ti/Makefile
> @@ -29,7 +29,7 @@ keystone_netcp_ethss-y := netcp_ethss.o netcp_sgmii.o netcp_xgbepcsr.o cpsw_ale.
>   obj-$(CONFIG_TI_K3_CPPI_DESC_POOL) += k3-cppi-desc-pool.o
>   
>   obj-$(CONFIG_TI_K3_AM65_CPSW_NUSS) += ti-am65-cpsw-nuss.o
> -ti-am65-cpsw-nuss-y := am65-cpsw-nuss.o cpsw_sl.o am65-cpsw-ethtool.o cpsw_ale.o
> +ti-am65-cpsw-nuss-y := am65-cpsw-nuss.o cpsw_sl.o am65-cpsw-ethtool.o cpsw_ale.o am65-cpsw-xdp.o
>   ti-am65-cpsw-nuss-$(CONFIG_TI_AM65_CPSW_QOS) += am65-cpsw-qos.o
>   ti-am65-cpsw-nuss-$(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV) += am65-cpsw-switchdev.o
>   obj-$(CONFIG_TI_K3_AM65_CPTS) += am65-cpts.o
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> index f9e2286efa29bbb7056fda1fc82c38b479aae8bd..46523be93df27710be77b288c36c1a0f66d8ca8d 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> @@ -58,9 +58,6 @@
>   
>   #define AM65_CPSW_MAX_PORTS	8
>   
> -#define AM65_CPSW_MIN_PACKET_SIZE	VLAN_ETH_ZLEN
> -#define AM65_CPSW_MAX_PACKET_SIZE	2024
> -
>   #define AM65_CPSW_REG_CTL		0x004
>   #define AM65_CPSW_REG_STAT_PORT_EN	0x014
>   #define AM65_CPSW_REG_PTYPE		0x018
> @@ -505,7 +502,7 @@ static inline void am65_cpsw_put_page(struct am65_cpsw_rx_flow *flow,
>   static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma);
>   static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma);
>   
> -static void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool)
> +void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool)
>   {
>   	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
>   	struct am65_cpsw_rx_flow *flow;
> @@ -554,7 +551,7 @@ static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common, bool retain_
>   	k3_udma_glue_disable_rx_chn(common->rx_chns.rx_chn);
>   }
>   
> -static int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
> +int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
>   {
>   	struct am65_cpsw_rx_chn *rx_chn = &common->rx_chns;
>   	struct page_pool_params pp_params = {
> @@ -663,7 +660,7 @@ static int am65_cpsw_create_rxqs(struct am65_cpsw_common *common)
>   	return ret;
>   }
>   
> -static void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
> +void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
>   {
>   	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
>   
> @@ -697,7 +694,7 @@ static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
>   		am65_cpsw_destroy_txq(common, id);
>   }
>   
> -static int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
> +int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
>   {
>   	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
>   	int ret;
> @@ -1327,7 +1324,7 @@ static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
>   	dma_unmap_single(rx_chn->dma_dev, buf_dma, buf_dma_len, DMA_FROM_DEVICE);
>   	k3_cppi_desc_pool_free(rx_chn->desc_pool, desc_rx);
>   
> -	if (port->xdp_prog) {
> +	if (am65_cpsw_xdp_is_enabled(port)) {
>   		xdp_init_buff(&xdp, PAGE_SIZE, &port->xdp_rxq[flow->id]);
>   		xdp_prepare_buff(&xdp, page_addr, AM65_CPSW_HEADROOM,
>   				 pkt_len, false);
> @@ -1961,6 +1958,9 @@ static int am65_cpsw_ndo_bpf(struct net_device *ndev, struct netdev_bpf *bpf)
>   	switch (bpf->command) {
>   	case XDP_SETUP_PROG:
>   		return am65_cpsw_xdp_prog_setup(ndev, bpf->prog);
> +	case XDP_SETUP_XSK_POOL:
> +		return am65_cpsw_xsk_setup_pool(ndev, bpf->xsk.pool,
> +						bpf->xsk.queue_id);
>   	default:
>   		return -EINVAL;
>   	}
> @@ -3553,7 +3553,12 @@ static int am65_cpsw_nuss_probe(struct platform_device *pdev)
>   	common = devm_kzalloc(dev, sizeof(struct am65_cpsw_common), GFP_KERNEL);
>   	if (!common)
>   		return -ENOMEM;
> +
>   	common->dev = dev;
> +	common->xdp_zc_queues = devm_bitmap_zalloc(dev, AM65_CPSW_MAX_QUEUES,
> +						   GFP_KERNEL);
> +	if (!common->xdp_zc_queues)
> +		return -ENOMEM;
>   
>   	of_id = of_match_device(am65_cpsw_nuss_of_mtable, dev);
>   	if (!of_id)
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.h b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> index 917c37e4e89bd933d3001f6c35a62db01cd8da4c..31789b5e5e1fc96be20cce17234d0e16cdcea796 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> @@ -23,8 +23,14 @@ struct am65_cpts;
>   
>   #define AM65_CPSW_MAX_QUEUES	8	/* both TX & RX */
>   
> +#define AM65_CPSW_MIN_PACKET_SIZE	VLAN_ETH_ZLEN
> +#define AM65_CPSW_MAX_PACKET_SIZE	2024
> +
>   #define AM65_CPSW_PORT_VLAN_REG_OFFSET	0x014
>   
> +#define AM65_CPSW_RX_DMA_ATTR	(DMA_ATTR_SKIP_CPU_SYNC |\
> +				 DMA_ATTR_WEAK_ORDERING)
> +
>   struct am65_cpsw_slave_data {
>   	bool				mac_only;
>   	struct cpsw_sl			*mac_sl;
> @@ -190,6 +196,9 @@ struct am65_cpsw_common {
>   	unsigned char switch_id[MAX_PHYS_ITEM_ID_LEN];
>   	/* only for suspend/resume context restore */
>   	u32			*ale_context;
> +	/* XDP Zero Copy */
> +	unsigned long		*xdp_zc_queues;
> +	int			xsk_port_id[AM65_CPSW_MAX_QUEUES];
>   };
>   
>   struct am65_cpsw_ndev_priv {
> @@ -228,4 +237,15 @@ int am65_cpsw_nuss_update_tx_rx_chns(struct am65_cpsw_common *common,
>   
>   bool am65_cpsw_port_dev_check(const struct net_device *dev);
>   
> +int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id);
> +void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_page_pool);
> +int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id);
> +void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id);
> +int am65_cpsw_xsk_setup_pool(struct net_device *ndev,
> +			     struct xsk_buff_pool *pool, u16 qid);
> +int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags);
> +static inline bool am65_cpsw_xdp_is_enabled(struct am65_cpsw_port *port)
> +{
> +	return !!READ_ONCE(port->xdp_prog);
> +}
>   #endif /* AM65_CPSW_NUSS_H_ */
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-xdp.c b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
> new file mode 100644
> index 0000000000000000000000000000000000000000..89f43f7c83db35dba96621bae930172e0fc85b6a
> --- /dev/null
> +++ b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
> @@ -0,0 +1,122 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/* Texas Instruments K3 AM65 Ethernet Switch SubSystem Driver
> + *
> + * Copyright (C) 2025 Texas Instruments Incorporated - http://www.ti.com/
> + *
> + */
> +
> +#include <net/xsk_buff_pool.h>
> +#include <net/xdp_sock_drv.h>
> +#include "am65-cpsw-nuss.h"
> +
> +static int am65_cpsw_xsk_pool_enable(struct am65_cpsw_port *port,
> +				     struct xsk_buff_pool *pool, u16 qid)
> +{
> +	struct am65_cpsw_common *common = port->common;
> +	struct am65_cpsw_rx_chn *rx_chn;
> +	bool need_update;
> +	u32 frame_size;
> +	int ret;
> +
> +	/*
> +	 * As queues are shared between ports we can no longer
> +	 * support the case where zero copy (XSK Pool) is enabled
> +	 * for the queue on one port but not for other ports.
> +	 *
> +	 * Current solution is to drop the packet if Zero copy
> +	 * is not enabled for that port + queue but enabled for
> +	 * some other port + same queue.
> +	 */
> +	if (test_bit(qid, common->xdp_zc_queues))
> +		return -EINVAL;
> +
> +	rx_chn = &common->rx_chns;
> +	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
> +		return -EINVAL;
> +
> +	frame_size = xsk_pool_get_rx_frame_size(pool);
> +	if (frame_size < AM65_CPSW_MAX_PACKET_SIZE)
> +		return -EOPNOTSUPP;
> +
> +	ret = xsk_pool_dma_map(pool, rx_chn->dma_dev, AM65_CPSW_RX_DMA_ATTR);
> +	if (ret) {
> +		netdev_err(port->ndev, "Failed to map xsk pool\n");
> +		return ret;
> +	}
> +
> +	need_update = common->usage_count &&
> +		      am65_cpsw_xdp_is_enabled(port);
> +	if (need_update) {
> +		am65_cpsw_destroy_rxq(common, qid, true);
> +		am65_cpsw_destroy_txq(common, qid);
> +	}
> +
> +	set_bit(qid, common->xdp_zc_queues);
> +	common->xsk_port_id[qid] = port->port_id;
> +	if (need_update) {
> +		am65_cpsw_create_rxq(common, qid);
> +		am65_cpsw_create_txq(common, qid);
> +	}
> +
> +	return 0;
> +}
> +
> +static int am65_cpsw_xsk_pool_disable(struct am65_cpsw_port *port,
> +				      struct xsk_buff_pool *pool, u16 qid)
> +{
> +	struct am65_cpsw_common *common = port->common;
> +	bool need_update;
> +
> +	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
> +		return -EINVAL;
> +
> +	if (!test_bit(qid, common->xdp_zc_queues))
> +		return -EINVAL;
> +
> +	pool = xsk_get_pool_from_qid(port->ndev, qid);
> +	if (!pool)
> +		return -EINVAL;
> +
> +	need_update = common->usage_count && am65_cpsw_xdp_is_enabled(port);
> +	if (need_update) {
> +		am65_cpsw_destroy_rxq(common, qid, true);
> +		am65_cpsw_destroy_txq(common, qid);
> +		synchronize_rcu();
> +	}
> +
> +	xsk_pool_dma_unmap(pool, AM65_CPSW_RX_DMA_ATTR);
> +	clear_bit(qid, common->xdp_zc_queues);
> +	common->xsk_port_id[qid] = -EINVAL;
> +	if (need_update) {
> +		am65_cpsw_create_rxq(common, qid);
> +		am65_cpsw_create_txq(common, qid);
> +	}
> +
> +	return 0;
> +}
> +
> +int am65_cpsw_xsk_setup_pool(struct net_device *ndev,
> +			     struct xsk_buff_pool *pool, u16 qid)
> +{
> +	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
> +
> +	return pool ? am65_cpsw_xsk_pool_enable(port, pool, qid) :
> +		      am65_cpsw_xsk_pool_disable(port, pool, qid);
> +}
> +
> +int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
> +{
> +	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
> +	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
> +
> +	if (!netif_running(ndev) || !netif_carrier_ok(ndev))
> +		return -ENETDOWN;
> +
> +	if (!am65_cpsw_xdp_is_enabled(port))
> +		return -EINVAL;
> +
> +	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
> +		return -EINVAL;
> +
> +	return 0;
> +}

Best regards,

Daolin

Texas Instruments Sitara MPU Systems Applications

[PATCH net-next v2 4/7] net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for RX

[Roger Quadros]

Add zero copy support to RX path.

Introduce xsk_pool and xsk_port_id to struct am65_cpsw_rx_flow.
This way we can quickly check if the flow is setup as XSK pool
and for which port.

If the RX flow is setup as XSK pool then register it as
MEM_TYPE_XSK_BUFF_POOL. At queue creation get free frames from
the XSK pool and push it to the RX ring.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 317 +++++++++++++++++++++++++++----
 drivers/net/ethernet/ti/am65-cpsw-nuss.h |  12 +-
 drivers/net/ethernet/ti/am65-cpsw-xdp.c  |  24 +++
 3 files changed, 319 insertions(+), 34 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 46523be93df27710be77b288c36c1a0f66d8ca8d..afc0c8836fe242d8bf47ce9bcd3e6b725ca37bf9 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -429,6 +429,55 @@ static void am65_cpsw_nuss_ndo_host_tx_timeout(struct net_device *ndev,
 	}
 }
 
+static int am65_cpsw_nuss_rx_push_zc(struct am65_cpsw_rx_flow *flow,
+				     struct xdp_buff *xdp)
+{
+	struct am65_cpsw_rx_chn *rx_chn = &flow->common->rx_chns;
+	struct cppi5_host_desc_t *desc_rx;
+	struct am65_cpsw_swdata *swdata;
+	u32 flow_id = flow->id;
+	dma_addr_t desc_dma;
+	dma_addr_t buf_dma;
+	int buf_len;
+
+	desc_rx = k3_cppi_desc_pool_alloc(rx_chn->desc_pool);
+	if (!desc_rx)
+		return -ENOMEM;
+
+	desc_dma = k3_cppi_desc_pool_virt2dma(rx_chn->desc_pool, desc_rx);
+	buf_dma = xsk_buff_xdp_get_dma(xdp);
+	cppi5_hdesc_init(desc_rx, CPPI5_INFO0_HDESC_EPIB_PRESENT,
+			 AM65_CPSW_NAV_PS_DATA_SIZE);
+	k3_udma_glue_rx_dma_to_cppi5_addr(rx_chn->rx_chn, &buf_dma);
+	buf_len = xsk_pool_get_rx_frame_size(flow->xsk_pool);
+	cppi5_hdesc_attach_buf(desc_rx, buf_dma, buf_len, buf_dma, buf_len);
+	swdata = cppi5_hdesc_get_swdata(desc_rx);
+	swdata->xdp = xdp;
+	swdata->flow_id = flow_id;
+
+	return k3_udma_glue_push_rx_chn(rx_chn->rx_chn, flow_id,
+					desc_rx, desc_dma);
+}
+
+static int am65_cpsw_nuss_rx_alloc_zc(struct am65_cpsw_rx_flow *flow,
+				      int budget)
+{
+	struct xdp_buff *xdp;
+	int i, ret;
+
+	for (i = 0; i < budget; i++) {
+		xdp = xsk_buff_alloc(flow->xsk_pool);
+		if (!xdp)
+			break;
+
+		ret = am65_cpsw_nuss_rx_push_zc(flow, xdp);
+		if (ret < 0)
+			break;
+	}
+
+	return i;
+}
+
 static int am65_cpsw_nuss_rx_push(struct am65_cpsw_common *common,
 				  struct page *page, u32 flow_idx)
 {
@@ -529,6 +578,9 @@ void am65_cpsw_destroy_rxq(struct am65_cpsw_common *common, int id, bool retain_
 		page_pool_destroy(flow->page_pool);
 		flow->page_pool = NULL;
 	}
+
+	flow->xsk_pool = NULL;
+	flow->xsk_port_id = -EINVAL;
 }
 
 static void am65_cpsw_destroy_rxqs(struct am65_cpsw_common *common, bool retain_page_pool)
@@ -568,6 +620,7 @@ int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 	struct page_pool *pool;
 	struct page *page;
 	int port, ret, i;
+	int port_id;
 
 	flow = &rx_chn->flows[id];
 	pp_params.napi = &flow->napi_rx;
@@ -587,9 +640,30 @@ int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 	/* using same page pool is allowed as no running rx handlers
 	 * simultaneously for both ndevs
 	 */
+
+	/* get first port with XSK pool & XDP program set */
+	for (port = 0; port < common->port_num; port++) {
+		if (!common->ports[port].ndev)
+			continue;
+
+		flow->xsk_pool = am65_cpsw_xsk_get_pool(&common->ports[port],
+							id);
+		if (flow->xsk_pool)
+			break;
+	}
+
+	port_id = common->ports[port].port_id;
+	flow->xsk_port_id = flow->xsk_pool ? port_id : -EINVAL;
 	for (port = 0; port < common->port_num; port++) {
 		if (!common->ports[port].ndev)
-		/* FIXME should we BUG here? */
+			continue;
+
+		port_id = common->ports[port].port_id;
+
+		/* NOTE: if queue is XSK then only register it
+		 * for the relevant port it was assigned to
+		 */
+		if (flow->xsk_pool && port_id != flow->xsk_port_id)
 			continue;
 
 		rxq = &common->ports[port].xdp_rxq[id];
@@ -598,29 +672,44 @@ int am65_cpsw_create_rxq(struct am65_cpsw_common *common, int id)
 		if (ret)
 			goto err;
 
-		ret = xdp_rxq_info_reg_mem_model(rxq,
-						 MEM_TYPE_PAGE_POOL,
-						 pool);
+		if (flow->xsk_pool) {
+			ret = xdp_rxq_info_reg_mem_model(rxq,
+							 MEM_TYPE_XSK_BUFF_POOL,
+							 NULL);
+			xsk_pool_set_rxq_info(flow->xsk_pool, rxq);
+		} else {
+			ret = xdp_rxq_info_reg_mem_model(rxq,
+							 MEM_TYPE_PAGE_POOL,
+							 pool);
+		}
+
 		if (ret)
 			goto err;
 	}
 
-	for (i = 0; i < AM65_CPSW_MAX_RX_DESC; i++) {
-		page = page_pool_dev_alloc_pages(flow->page_pool);
-		if (!page) {
-			dev_err(common->dev, "cannot allocate page in flow %d\n",
-				id);
-			ret = -ENOMEM;
-			goto err;
-		}
+	if (flow->xsk_pool) {
+		/* get pages from xsk_pool and push to RX ring
+		 * queue as much as possible
+		 */
+		am65_cpsw_nuss_rx_alloc_zc(flow, AM65_CPSW_MAX_RX_DESC);
+	} else {
+		for (i = 0; i < AM65_CPSW_MAX_RX_DESC; i++) {
+			page = page_pool_dev_alloc_pages(flow->page_pool);
+			if (!page) {
+				dev_err(common->dev, "cannot allocate page in flow %d\n",
+					id);
+				ret = -ENOMEM;
+				goto err;
+			}
 
-		ret = am65_cpsw_nuss_rx_push(common, page, id);
-		if (ret < 0) {
-			dev_err(common->dev,
-				"cannot submit page to rx channel flow %d, error %d\n",
-				id, ret);
-			am65_cpsw_put_page(flow, page, false);
-			goto err;
+			ret = am65_cpsw_nuss_rx_push(common, page, id);
+			if (ret < 0) {
+				dev_err(common->dev,
+					"cannot submit page to rx channel flow %d, error %d\n",
+					id, ret);
+				am65_cpsw_put_page(flow, page, false);
+				goto err;
+			}
 		}
 	}
 
@@ -777,6 +866,8 @@ static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma)
 	struct am65_cpsw_rx_chn *rx_chn = data;
 	struct cppi5_host_desc_t *desc_rx;
 	struct am65_cpsw_swdata *swdata;
+	struct am65_cpsw_rx_flow *flow;
+	struct xdp_buff *xdp;
 	dma_addr_t buf_dma;
 	struct page *page;
 	u32 buf_dma_len;
@@ -784,13 +875,20 @@ static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma)
 
 	desc_rx = k3_cppi_desc_pool_dma2virt(rx_chn->desc_pool, desc_dma);
 	swdata = cppi5_hdesc_get_swdata(desc_rx);
-	page = swdata->page;
 	flow_id = swdata->flow_id;
 	cppi5_hdesc_get_obuf(desc_rx, &buf_dma, &buf_dma_len);
 	k3_udma_glue_rx_cppi5_to_dma_addr(rx_chn->rx_chn, &buf_dma);
-	dma_unmap_single(rx_chn->dma_dev, buf_dma, buf_dma_len, DMA_FROM_DEVICE);
 	k3_cppi_desc_pool_free(rx_chn->desc_pool, desc_rx);
-	am65_cpsw_put_page(&rx_chn->flows[flow_id], page, false);
+	flow = &rx_chn->flows[flow_id];
+	if (flow->xsk_pool) {
+		xdp = swdata->xdp;
+		xsk_buff_free(xdp);
+	} else {
+		page = swdata->page;
+		dma_unmap_single(rx_chn->dma_dev, buf_dma, buf_dma_len,
+				 DMA_FROM_DEVICE);
+		am65_cpsw_put_page(flow, page, false);
+	}
 }
 
 static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
@@ -1267,6 +1365,151 @@ static void am65_cpsw_nuss_rx_csum(struct sk_buff *skb, u32 csum_info)
 	}
 }
 
+static struct sk_buff *am65_cpsw_create_skb_zc(struct am65_cpsw_rx_flow *flow,
+					       struct xdp_buff *xdp)
+{
+	unsigned int metasize = xdp->data - xdp->data_meta;
+	unsigned int datasize = xdp->data_end - xdp->data;
+	struct sk_buff *skb;
+
+	skb = napi_alloc_skb(&flow->napi_rx,
+			     xdp->data_end - xdp->data_hard_start);
+	if (unlikely(!skb))
+		return NULL;
+
+	skb_reserve(skb, xdp->data - xdp->data_hard_start);
+	memcpy(__skb_put(skb, datasize), xdp->data, datasize);
+	if (metasize)
+		skb_metadata_set(skb, metasize);
+
+	return skb;
+}
+
+static void am65_cpsw_dispatch_skb_zc(struct am65_cpsw_rx_flow *flow,
+				      struct am65_cpsw_port *port,
+				      struct xdp_buff *xdp, u32 csum_info)
+{
+	struct am65_cpsw_common *common = flow->common;
+	unsigned int len = xdp->data_end - xdp->data;
+	struct am65_cpsw_ndev_priv *ndev_priv;
+	struct net_device *ndev = port->ndev;
+	struct sk_buff *skb;
+
+	skb = am65_cpsw_create_skb_zc(flow, xdp);
+	if (!skb) {
+		ndev->stats.rx_dropped++;
+		return;
+	}
+
+	ndev_priv = netdev_priv(ndev);
+	am65_cpsw_nuss_set_offload_fwd_mark(skb, ndev_priv->offload_fwd_mark);
+	if (port->rx_ts_enabled)
+		am65_cpts_rx_timestamp(common->cpts, skb);
+
+	skb_mark_for_recycle(skb);
+	skb->protocol = eth_type_trans(skb, ndev);
+	am65_cpsw_nuss_rx_csum(skb, csum_info);
+	napi_gro_receive(&flow->napi_rx, skb);
+	dev_sw_netstats_rx_add(ndev, len);
+}
+
+static int am65_cpsw_nuss_rx_zc(struct am65_cpsw_rx_flow *flow, int budget)
+{
+	struct am65_cpsw_rx_chn *rx_chn = &flow->common->rx_chns;
+	u32 buf_dma_len, pkt_len, port_id = 0, csum_info;
+	struct am65_cpsw_common *common = flow->common;
+	struct cppi5_host_desc_t *desc_rx;
+	struct device *dev = common->dev;
+	struct am65_cpsw_swdata *swdata;
+	dma_addr_t desc_dma, buf_dma;
+	struct am65_cpsw_port *port;
+	struct net_device *ndev;
+	u32 flow_idx = flow->id;
+	struct xdp_buff	*xdp;
+	int count = 0;
+	int xdp_status = 0;
+	u32 *psdata;
+	int ret;
+
+	while (count < budget) {
+		ret = k3_udma_glue_pop_rx_chn(rx_chn->rx_chn, flow_idx,
+					      &desc_dma);
+		if (ret) {
+			if (ret != -ENODATA)
+				dev_err(dev, "RX: pop chn fail %d\n",
+					ret);
+			break;
+		}
+
+		if (cppi5_desc_is_tdcm(desc_dma)) {
+			dev_dbg(dev, "%s RX tdown flow: %u\n",
+				__func__, flow_idx);
+			if (common->pdata.quirks & AM64_CPSW_QUIRK_DMA_RX_TDOWN_IRQ)
+				complete(&common->tdown_complete);
+			continue;
+		}
+
+		desc_rx = k3_cppi_desc_pool_dma2virt(rx_chn->desc_pool,
+						     desc_dma);
+		dev_dbg(dev, "%s flow_idx: %u desc %pad\n",
+			__func__, flow_idx, &desc_dma);
+
+		swdata = cppi5_hdesc_get_swdata(desc_rx);
+		xdp = swdata->xdp;
+		cppi5_hdesc_get_obuf(desc_rx, &buf_dma, &buf_dma_len);
+		k3_udma_glue_rx_cppi5_to_dma_addr(rx_chn->rx_chn, &buf_dma);
+		pkt_len = cppi5_hdesc_get_pktlen(desc_rx);
+		cppi5_desc_get_tags_ids(&desc_rx->hdr, &port_id, NULL);
+		dev_dbg(dev, "%s rx port_id:%d\n", __func__, port_id);
+		port = am65_common_get_port(common, port_id);
+		ndev = port->ndev;
+		psdata = cppi5_hdesc_get_psdata(desc_rx);
+		csum_info = psdata[2];
+		dev_dbg(dev, "%s rx csum_info:%#x\n", __func__, csum_info);
+		k3_cppi_desc_pool_free(rx_chn->desc_pool, desc_rx);
+		count++;
+		xsk_buff_set_size(xdp, pkt_len);
+		xsk_buff_dma_sync_for_cpu(xdp);
+		/* check if this port has XSK enabled. else drop packet */
+		if (port_id != flow->xsk_port_id) {
+			dev_dbg(dev, "discarding non xsk port data\n");
+			xsk_buff_free(xdp);
+			ndev->stats.rx_dropped++;
+			continue;
+		}
+
+		ret = am65_cpsw_run_xdp(flow, port, xdp, &pkt_len);
+		switch (ret) {
+		case AM65_CPSW_XDP_PASS:
+			am65_cpsw_dispatch_skb_zc(flow, port, xdp, csum_info);
+			xsk_buff_free(xdp);
+			break;
+		case AM65_CPSW_XDP_CONSUMED:
+			xsk_buff_free(xdp);
+			break;
+		case AM65_CPSW_XDP_TX:
+		case AM65_CPSW_XDP_REDIRECT:
+			xdp_status |= ret;
+			break;
+		}
+	}
+
+	if (xdp_status & AM65_CPSW_XDP_REDIRECT)
+		xdp_do_flush();
+
+	ret = am65_cpsw_nuss_rx_alloc_zc(flow, count);
+
+	if (xsk_uses_need_wakeup(flow->xsk_pool)) {
+		/* We set wakeup if we are exhausted of new requests */
+		if (ret < count)
+			xsk_set_rx_need_wakeup(flow->xsk_pool);
+		else
+			xsk_clear_rx_need_wakeup(flow->xsk_pool);
+	}
+
+	return count;
+}
+
 static int am65_cpsw_nuss_rx_packets(struct am65_cpsw_rx_flow *flow,
 				     int *xdp_state)
 {
@@ -1392,7 +1635,11 @@ static enum hrtimer_restart am65_cpsw_nuss_rx_timer_callback(struct hrtimer *tim
 						      struct am65_cpsw_rx_flow,
 						      rx_hrtimer);
 
-	enable_irq(flow->irq);
+	if (flow->irq_disabled) {
+		flow->irq_disabled = false;
+		enable_irq(flow->irq);
+	}
+
 	return HRTIMER_NORESTART;
 }
 
@@ -1406,17 +1653,21 @@ static int am65_cpsw_nuss_rx_poll(struct napi_struct *napi_rx, int budget)
 	int num_rx = 0;
 
 	/* process only this flow */
-	cur_budget = budget;
-	while (cur_budget--) {
-		ret = am65_cpsw_nuss_rx_packets(flow, &xdp_state);
-		xdp_state_or |= xdp_state;
-		if (ret)
-			break;
-		num_rx++;
-	}
+	if (flow->xsk_pool) {
+		num_rx = am65_cpsw_nuss_rx_zc(flow, budget);
+	} else {
+		cur_budget = budget;
+		while (cur_budget--) {
+			ret = am65_cpsw_nuss_rx_packets(flow, &xdp_state);
+			xdp_state_or |= xdp_state;
+			if (ret)
+				break;
+			num_rx++;
+		}
 
-	if (xdp_state_or & AM65_CPSW_XDP_REDIRECT)
-		xdp_do_flush();
+		if (xdp_state_or & AM65_CPSW_XDP_REDIRECT)
+			xdp_do_flush();
+	}
 
 	dev_dbg(common->dev, "%s num_rx:%d %d\n", __func__, num_rx, budget);
 
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.h b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
index 31789b5e5e1fc96be20cce17234d0e16cdcea796..2bf4d12f92764706719cc1d65001dbb53da58c38 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
@@ -15,6 +15,7 @@
 #include <linux/soc/ti/k3-ringacc.h>
 #include <net/devlink.h>
 #include <net/xdp.h>
+#include <net/xdp_sock_drv.h>
 #include "am65-cpsw-qos.h"
 
 struct am65_cpts;
@@ -107,6 +108,8 @@ struct am65_cpsw_rx_flow {
 	struct hrtimer rx_hrtimer;
 	unsigned long rx_pace_timeout;
 	struct page_pool *page_pool;
+	struct xsk_buff_pool *xsk_pool;
+	int xsk_port_id;
 	char name[32];
 };
 
@@ -120,7 +123,10 @@ struct am65_cpsw_tx_swdata {
 
 struct am65_cpsw_swdata {
 	u32 flow_id;
-	struct page *page;
+	union {
+		struct page *page;
+		struct xdp_buff *xdp;
+	};
 };
 
 struct am65_cpsw_rx_chn {
@@ -248,4 +254,8 @@ static inline bool am65_cpsw_xdp_is_enabled(struct am65_cpsw_port *port)
 {
 	return !!READ_ONCE(port->xdp_prog);
 }
+
+struct xsk_buff_pool *am65_cpsw_xsk_get_pool(struct am65_cpsw_port *port,
+					     u32 qid);
+
 #endif /* AM65_CPSW_NUSS_H_ */
diff --git a/drivers/net/ethernet/ti/am65-cpsw-xdp.c b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
index 89f43f7c83db35dba96621bae930172e0fc85b6a..0e37c27f77720713430a3e70f6c4b3dfb048cfc0 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-xdp.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
@@ -108,6 +108,9 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
 {
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+	struct am65_cpsw_rx_flow *rx_flow;
+
+	rx_flow = &common->rx_chns.flows[qid];
 
 	if (!netif_running(ndev) || !netif_carrier_ok(ndev))
 		return -ENETDOWN;
@@ -118,5 +121,26 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
 	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
 		return -EINVAL;
 
+	if (!rx_flow->xsk_pool)
+		return -EINVAL;
+
+	if (flags & XDP_WAKEUP_RX) {
+		if (!napi_if_scheduled_mark_missed(&rx_flow->napi_rx)) {
+			if (likely(napi_schedule_prep(&rx_flow->napi_rx)))
+				__napi_schedule(&rx_flow->napi_rx);
+		}
+	}
+
 	return 0;
 }
+
+struct xsk_buff_pool *am65_cpsw_xsk_get_pool(struct am65_cpsw_port *port,
+					     u32 qid)
+{
+	if (!am65_cpsw_xdp_is_enabled(port) ||
+	    !test_bit(qid, port->common->xdp_zc_queues) ||
+	    port->common->xsk_port_id[qid] != port->port_id)
+		return NULL;
+
+	return xsk_get_pool_from_qid(port->ndev, qid);
+}

-- 
2.34.1

Re: [PATCH net-next v2 4/7] net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for RX

[Jakub Kicinski]

On Sun, 09 Nov 2025 23:37:54 +0200 Roger Quadros wrote:
> +			ndev->stats.rx_dropped++;

AFAIU the device is multi-queue so using per-device stats looks racy.
Please create your own per queue stats.

[PATCH net-next v2 5/7] net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for TX

[Roger Quadros]

Add zero copy support to TX path.

Introduce xsk_pool and xsk_port_id to struct am65_cpsw_tx_chn.
This way we can quickly check if the flow is setup as XSK pool
and for which port.

If the TX channel is setup as XSK pool then get the frames from
the pool and send it to the TX channel.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 171 ++++++++++++++++++++++++++++---
 drivers/net/ethernet/ti/am65-cpsw-nuss.h |   5 +
 drivers/net/ethernet/ti/am65-cpsw-xdp.c  |  11 +-
 3 files changed, 171 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index afc0c8836fe242d8bf47ce9bcd3e6b725ca37bf9..2e06e7df23ad5249786d081e51434f87dd2a76b5 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -758,6 +758,8 @@ void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
 	k3_udma_glue_reset_tx_chn(tx_chn->tx_chn, tx_chn,
 				  am65_cpsw_nuss_tx_cleanup);
 	k3_udma_glue_disable_tx_chn(tx_chn->tx_chn);
+	tx_chn->xsk_pool = NULL;
+	tx_chn->xsk_port_id = -EINVAL;
 }
 
 static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
@@ -786,12 +788,25 @@ static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
 int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
 {
 	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
-	int ret;
+	int port, ret;
 
 	ret = k3_udma_glue_enable_tx_chn(tx_chn->tx_chn);
 	if (ret)
 		return ret;
 
+	/* get first port with XSK pool & XDP program set */
+	for (port = 0; port < common->port_num; port++) {
+		if (!common->ports[port].ndev)
+			continue;
+
+		tx_chn->xsk_pool = am65_cpsw_xsk_get_pool(&common->ports[port],
+							  id);
+		if (tx_chn->xsk_pool)
+			break;
+	}
+
+	tx_chn->xsk_port_id = tx_chn->xsk_pool ?
+			      common->ports[port].port_id : -EINVAL;
 	napi_enable(&tx_chn->napi_tx);
 
 	return 0;
@@ -892,15 +907,18 @@ static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma)
 }
 
 static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
-				     struct cppi5_host_desc_t *desc)
+				     struct cppi5_host_desc_t *desc,
+				     enum am65_cpsw_tx_buf_type buf_type)
 {
 	struct cppi5_host_desc_t *first_desc, *next_desc;
 	dma_addr_t buf_dma, next_desc_dma;
 	u32 buf_dma_len;
 
 	first_desc = desc;
-	next_desc = first_desc;
+	if (buf_type == AM65_CPSW_TX_BUF_TYPE_XSK_TX)
+		goto free_pool;
 
+	next_desc = first_desc;
 	cppi5_hdesc_get_obuf(first_desc, &buf_dma, &buf_dma_len);
 	k3_udma_glue_tx_cppi5_to_dma_addr(tx_chn->tx_chn, &buf_dma);
 
@@ -923,6 +941,7 @@ static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
 		k3_cppi_desc_pool_free(tx_chn->desc_pool, next_desc);
 	}
 
+free_pool:
 	k3_cppi_desc_pool_free(tx_chn->desc_pool, first_desc);
 }
 
@@ -932,21 +951,32 @@ static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma)
 	enum am65_cpsw_tx_buf_type buf_type;
 	struct am65_cpsw_tx_swdata *swdata;
 	struct cppi5_host_desc_t *desc_tx;
+	struct xsk_buff_pool *xsk_pool;
 	struct xdp_frame *xdpf;
 	struct sk_buff *skb;
 
 	desc_tx = k3_cppi_desc_pool_dma2virt(tx_chn->desc_pool, desc_dma);
 	swdata = cppi5_hdesc_get_swdata(desc_tx);
 	buf_type = am65_cpsw_nuss_buf_type(tx_chn, desc_dma);
-	if (buf_type == AM65_CPSW_TX_BUF_TYPE_SKB) {
+	switch (buf_type) {
+	case AM65_CPSW_TX_BUF_TYPE_SKB:
 		skb = swdata->skb;
 		dev_kfree_skb_any(skb);
-	} else {
+		break;
+	case AM65_CPSW_TX_BUF_TYPE_XDP_TX:
+	case AM65_CPSW_TX_BUF_TYPE_XDP_NDO:
 		xdpf = swdata->xdpf;
 		xdp_return_frame(xdpf);
+		break;
+	case AM65_CPSW_TX_BUF_TYPE_XSK_TX:
+		xsk_pool = swdata->xsk_pool;
+		xsk_tx_completed(xsk_pool, 1);
+		break;
+	default:
+		break;
 	}
 
-	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
+	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx, buf_type);
 }
 
 static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
@@ -1189,6 +1219,82 @@ static int am65_cpsw_nuss_ndo_slave_open(struct net_device *ndev)
 	return ret;
 }
 
+static int am65_cpsw_xsk_xmit_zc(struct net_device *ndev,
+				 struct am65_cpsw_tx_chn *tx_chn)
+{
+	struct am65_cpsw_common *common = tx_chn->common;
+	struct xsk_buff_pool *pool = tx_chn->xsk_pool;
+	struct xdp_desc *xdp_descs = pool->tx_descs;
+	struct cppi5_host_desc_t *host_desc;
+	struct am65_cpsw_tx_swdata *swdata;
+	dma_addr_t dma_desc, dma_buf;
+	int num_tx = 0, pkt_len;
+	int descs_avail, ret;
+	int i;
+
+	descs_avail = k3_cppi_desc_pool_avail(tx_chn->desc_pool);
+	/* ensure that TX ring is not filled up by XDP, always MAX_SKB_FRAGS
+	 * will be available for normal TX path and queue is stopped there if
+	 * necessary
+	 */
+	if (descs_avail <= MAX_SKB_FRAGS)
+		return 0;
+
+	descs_avail -= MAX_SKB_FRAGS;
+	descs_avail = xsk_tx_peek_release_desc_batch(pool, descs_avail);
+
+	for (i = 0; i < descs_avail; i++) {
+		host_desc = k3_cppi_desc_pool_alloc(tx_chn->desc_pool);
+		if (unlikely(!host_desc))
+			break;
+
+		am65_cpsw_nuss_set_buf_type(tx_chn, host_desc,
+					    AM65_CPSW_TX_BUF_TYPE_XSK_TX);
+		dma_buf = xsk_buff_raw_get_dma(pool, xdp_descs[i].addr);
+		pkt_len = xdp_descs[i].len;
+		xsk_buff_raw_dma_sync_for_device(pool, dma_buf, pkt_len);
+
+		cppi5_hdesc_init(host_desc, CPPI5_INFO0_HDESC_EPIB_PRESENT,
+				 AM65_CPSW_NAV_PS_DATA_SIZE);
+		cppi5_hdesc_set_pkttype(host_desc, AM65_CPSW_CPPI_TX_PKT_TYPE);
+		cppi5_hdesc_set_pktlen(host_desc, pkt_len);
+		cppi5_desc_set_pktids(&host_desc->hdr, 0,
+				      AM65_CPSW_CPPI_TX_FLOW_ID);
+		cppi5_desc_set_tags_ids(&host_desc->hdr, 0,
+					tx_chn->xsk_port_id);
+
+		k3_udma_glue_tx_dma_to_cppi5_addr(tx_chn->tx_chn, &dma_buf);
+		cppi5_hdesc_attach_buf(host_desc, dma_buf, pkt_len, dma_buf,
+				       pkt_len);
+
+		swdata = cppi5_hdesc_get_swdata(host_desc);
+		swdata->ndev = ndev;
+		swdata->xsk_pool = pool;
+
+		dma_desc = k3_cppi_desc_pool_virt2dma(tx_chn->desc_pool,
+						      host_desc);
+		if (AM65_CPSW_IS_CPSW2G(common)) {
+			ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn,
+						       host_desc, dma_desc);
+		} else {
+			spin_lock_bh(&tx_chn->lock);
+			ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn,
+						       host_desc, dma_desc);
+			spin_unlock_bh(&tx_chn->lock);
+		}
+
+		if (ret) {
+			ndev->stats.tx_errors++;
+			k3_cppi_desc_pool_free(tx_chn->desc_pool, host_desc);
+			break;
+		}
+
+		num_tx++;
+	}
+
+	return num_tx;
+}
+
 static int am65_cpsw_xdp_tx_frame(struct net_device *ndev,
 				  struct am65_cpsw_tx_chn *tx_chn,
 				  struct xdp_frame *xdpf,
@@ -1716,15 +1822,19 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
 	struct netdev_queue *netif_txq;
 	unsigned int total_bytes = 0;
 	struct net_device *ndev;
+	int xsk_frames_done = 0;
 	struct xdp_frame *xdpf;
 	unsigned int pkt_len;
 	struct sk_buff *skb;
 	dma_addr_t desc_dma;
 	int res, num_tx = 0;
+	int xsk_tx = 0;
 
 	tx_chn = &common->tx_chns[chn];
 
 	while (true) {
+		pkt_len = 0;
+
 		if (!single_port)
 			spin_lock(&tx_chn->lock);
 		res = k3_udma_glue_pop_tx_chn(tx_chn->tx_chn, &desc_dma);
@@ -1746,25 +1856,36 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
 		swdata = cppi5_hdesc_get_swdata(desc_tx);
 		ndev = swdata->ndev;
 		buf_type = am65_cpsw_nuss_buf_type(tx_chn, desc_dma);
-		if (buf_type == AM65_CPSW_TX_BUF_TYPE_SKB) {
+		switch (buf_type) {
+		case AM65_CPSW_TX_BUF_TYPE_SKB:
 			skb = swdata->skb;
 			am65_cpts_tx_timestamp(tx_chn->common->cpts, skb);
 			pkt_len = skb->len;
 			napi_consume_skb(skb, budget);
-		} else {
+			total_bytes += pkt_len;
+			break;
+		case AM65_CPSW_TX_BUF_TYPE_XDP_TX:
+		case AM65_CPSW_TX_BUF_TYPE_XDP_NDO:
 			xdpf = swdata->xdpf;
 			pkt_len = xdpf->len;
+			total_bytes += pkt_len;
 			if (buf_type == AM65_CPSW_TX_BUF_TYPE_XDP_TX)
 				xdp_return_frame_rx_napi(xdpf);
 			else
 				xdp_return_frame(xdpf);
+			break;
+		case AM65_CPSW_TX_BUF_TYPE_XSK_TX:
+			pkt_len = cppi5_hdesc_get_pktlen(desc_tx);
+			xsk_frames_done++;
+			break;
+		default:
+			break;
 		}
 
-		total_bytes += pkt_len;
 		num_tx++;
-		am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
+		am65_cpsw_nuss_xmit_free(tx_chn, desc_tx, buf_type);
 		dev_sw_netstats_tx_add(ndev, 1, pkt_len);
-		if (!single_port) {
+		if (!single_port && buf_type != AM65_CPSW_TX_BUF_TYPE_XSK_TX) {
 			/* as packets from multi ports can be interleaved
 			 * on the same channel, we have to figure out the
 			 * port/queue at every packet and report it/wake queue.
@@ -1781,6 +1902,19 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
 		am65_cpsw_nuss_tx_wake(tx_chn, ndev, netif_txq);
 	}
 
+	if (tx_chn->xsk_pool) {
+		if (xsk_frames_done)
+			xsk_tx_completed(tx_chn->xsk_pool, xsk_frames_done);
+
+		if (xsk_uses_need_wakeup(tx_chn->xsk_pool))
+			xsk_set_tx_need_wakeup(tx_chn->xsk_pool);
+
+		ndev = common->ports[tx_chn->xsk_port_id].ndev;
+		netif_txq = netdev_get_tx_queue(ndev, chn);
+		txq_trans_cond_update(netif_txq);
+		xsk_tx = am65_cpsw_xsk_xmit_zc(ndev, tx_chn);
+	}
+
 	dev_dbg(dev, "%s:%u pkt:%d\n", __func__, chn, num_tx);
 
 	return num_tx;
@@ -1791,7 +1925,11 @@ static enum hrtimer_restart am65_cpsw_nuss_tx_timer_callback(struct hrtimer *tim
 	struct am65_cpsw_tx_chn *tx_chns =
 			container_of(timer, struct am65_cpsw_tx_chn, tx_hrtimer);
 
-	enable_irq(tx_chns->irq);
+	if (tx_chns->irq_disabled) {
+		tx_chns->irq_disabled = false;
+		enable_irq(tx_chns->irq);
+	}
+
 	return HRTIMER_NORESTART;
 }
 
@@ -1811,7 +1949,8 @@ static int am65_cpsw_nuss_tx_poll(struct napi_struct *napi_tx, int budget)
 			hrtimer_start(&tx_chn->tx_hrtimer,
 				      ns_to_ktime(tx_chn->tx_pace_timeout),
 				      HRTIMER_MODE_REL_PINNED);
-		} else {
+		} else if (tx_chn->irq_disabled) {
+			tx_chn->irq_disabled = false;
 			enable_irq(tx_chn->irq);
 		}
 	}
@@ -1834,6 +1973,7 @@ static irqreturn_t am65_cpsw_nuss_tx_irq(int irq, void *dev_id)
 {
 	struct am65_cpsw_tx_chn *tx_chn = dev_id;
 
+	tx_chn->irq_disabled = true;
 	disable_irq_nosync(irq);
 	napi_schedule(&tx_chn->napi_tx);
 
@@ -1998,14 +2138,14 @@ static netdev_tx_t am65_cpsw_nuss_ndo_slave_xmit(struct sk_buff *skb,
 	return NETDEV_TX_OK;
 
 err_free_descs:
-	am65_cpsw_nuss_xmit_free(tx_chn, first_desc);
+	am65_cpsw_nuss_xmit_free(tx_chn, first_desc, AM65_CPSW_TX_BUF_TYPE_SKB);
 err_free_skb:
 	ndev->stats.tx_dropped++;
 	dev_kfree_skb_any(skb);
 	return NETDEV_TX_OK;
 
 busy_free_descs:
-	am65_cpsw_nuss_xmit_free(tx_chn, first_desc);
+	am65_cpsw_nuss_xmit_free(tx_chn, first_desc, AM65_CPSW_TX_BUF_TYPE_SKB);
 busy_stop_q:
 	netif_tx_stop_queue(netif_txq);
 	return NETDEV_TX_BUSY;
@@ -2259,6 +2399,7 @@ static const struct net_device_ops am65_cpsw_nuss_netdev_ops = {
 	.ndo_xdp_xmit		= am65_cpsw_ndo_xdp_xmit,
 	.ndo_hwtstamp_get       = am65_cpsw_nuss_hwtstamp_get,
 	.ndo_hwtstamp_set       = am65_cpsw_nuss_hwtstamp_set,
+	.ndo_xsk_wakeup		= am65_cpsw_xsk_wakeup,
 };
 
 static void am65_cpsw_disable_phy(struct phy *phy)
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.h b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
index 2bf4d12f92764706719cc1d65001dbb53da58c38..ac2d9d32e95b932665131a317df8316cb6cb7f96 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
@@ -72,6 +72,7 @@ enum am65_cpsw_tx_buf_type {
 	AM65_CPSW_TX_BUF_TYPE_SKB,
 	AM65_CPSW_TX_BUF_TYPE_XDP_TX,
 	AM65_CPSW_TX_BUF_TYPE_XDP_NDO,
+	AM65_CPSW_TX_BUF_TYPE_XSK_TX,
 };
 
 struct am65_cpsw_host {
@@ -97,6 +98,9 @@ struct am65_cpsw_tx_chn {
 	unsigned char dsize_log2;
 	char tx_chn_name[128];
 	u32 rate_mbps;
+	struct xsk_buff_pool *xsk_pool;
+	int xsk_port_id;
+	bool irq_disabled;
 };
 
 struct am65_cpsw_rx_flow {
@@ -118,6 +122,7 @@ struct am65_cpsw_tx_swdata {
 	union {
 		struct sk_buff *skb;
 		struct xdp_frame *xdpf;
+		struct xsk_buff_pool *xsk_pool;
 	};
 };
 
diff --git a/drivers/net/ethernet/ti/am65-cpsw-xdp.c b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
index 0e37c27f77720713430a3e70f6c4b3dfb048cfc0..9adf13056f70fea36d9aeac157b7da0cae2c011e 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-xdp.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
@@ -109,8 +109,10 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
 	struct am65_cpsw_rx_flow *rx_flow;
+	struct am65_cpsw_tx_chn *tx_ch;
 
 	rx_flow = &common->rx_chns.flows[qid];
+	tx_ch = &common->tx_chns[qid];
 
 	if (!netif_running(ndev) || !netif_carrier_ok(ndev))
 		return -ENETDOWN;
@@ -121,9 +123,16 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
 	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
 		return -EINVAL;
 
-	if (!rx_flow->xsk_pool)
+	if (!rx_flow->xsk_pool && !tx_ch->xsk_pool)
 		return -EINVAL;
 
+	if (flags & XDP_WAKEUP_TX) {
+		if (!napi_if_scheduled_mark_missed(&tx_ch->napi_tx)) {
+			if (likely(napi_schedule_prep(&tx_ch->napi_tx)))
+				__napi_schedule(&tx_ch->napi_tx);
+		}
+	}
+
 	if (flags & XDP_WAKEUP_RX) {
 		if (!napi_if_scheduled_mark_missed(&rx_flow->napi_rx)) {
 			if (likely(napi_schedule_prep(&rx_flow->napi_rx)))

-- 
2.34.1

Re: [PATCH net-next v2 5/7] net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for TX

[Qiu, Daolin]

Hi Roger,

My name is Daolin (a colleague of Meghana's).

This is my first time responding to a Linux Kernel mailing list so 
please be patient if I'm potentially violating any conventions or rules 
in my message.

Recently, I've encountered the same kernel crash that Meghana faced 
(https://gist.github.com/MeghanaMalladiTI/784fd2262d95b19fe9573c553c4a6a24 
) when I was testing the eth1 interface of the CPSW with your patches on 
an AM62x EVM and found a potential source of the problem (see below).

On 11/9/2025 3:37 PM, Roger Quadros wrote:
> Add zero copy support to TX path.
>
> Introduce xsk_pool and xsk_port_id to struct am65_cpsw_tx_chn.
> This way we can quickly check if the flow is setup as XSK pool
> and for which port.
>
> If the TX channel is setup as XSK pool then get the frames from
> the pool and send it to the TX channel.
>
> Signed-off-by: Roger Quadros <rogerq@kernel.org>
> ---
>   drivers/net/ethernet/ti/am65-cpsw-nuss.c | 171 ++++++++++++++++++++++++++++---
>   drivers/net/ethernet/ti/am65-cpsw-nuss.h |   5 +
>   drivers/net/ethernet/ti/am65-cpsw-xdp.c  |  11 +-
>   3 files changed, 171 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> index afc0c8836fe242d8bf47ce9bcd3e6b725ca37bf9..2e06e7df23ad5249786d081e51434f87dd2a76b5 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
> @@ -758,6 +758,8 @@ void am65_cpsw_destroy_txq(struct am65_cpsw_common *common, int id)
>   	k3_udma_glue_reset_tx_chn(tx_chn->tx_chn, tx_chn,
>   				  am65_cpsw_nuss_tx_cleanup);
>   	k3_udma_glue_disable_tx_chn(tx_chn->tx_chn);
> +	tx_chn->xsk_pool = NULL;
> +	tx_chn->xsk_port_id = -EINVAL;
>   }
>   
>   static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
> @@ -786,12 +788,25 @@ static void am65_cpsw_destroy_txqs(struct am65_cpsw_common *common)
>   int am65_cpsw_create_txq(struct am65_cpsw_common *common, int id)
>   {
>   	struct am65_cpsw_tx_chn *tx_chn = &common->tx_chns[id];
> -	int ret;
> +	int port, ret;
>   
>   	ret = k3_udma_glue_enable_tx_chn(tx_chn->tx_chn);
>   	if (ret)
>   		return ret;
>   
> +	/* get first port with XSK pool & XDP program set */
> +	for (port = 0; port < common->port_num; port++) {
> +		if (!common->ports[port].ndev)
> +			continue;
> +
> +		tx_chn->xsk_pool = am65_cpsw_xsk_get_pool(&common->ports[port],
> +							  id);
> +		if (tx_chn->xsk_pool)
> +			break;
> +	}
> +
> +	tx_chn->xsk_port_id = tx_chn->xsk_pool ?
> +			      common->ports[port].port_id : -EINVAL;
>   	napi_enable(&tx_chn->napi_tx);
>   
>   	return 0;
> @@ -892,15 +907,18 @@ static void am65_cpsw_nuss_rx_cleanup(void *data, dma_addr_t desc_dma)
>   }
>   
>   static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
> -				     struct cppi5_host_desc_t *desc)
> +				     struct cppi5_host_desc_t *desc,
> +				     enum am65_cpsw_tx_buf_type buf_type)
>   {
>   	struct cppi5_host_desc_t *first_desc, *next_desc;
>   	dma_addr_t buf_dma, next_desc_dma;
>   	u32 buf_dma_len;
>   
>   	first_desc = desc;
> -	next_desc = first_desc;
> +	if (buf_type == AM65_CPSW_TX_BUF_TYPE_XSK_TX)
> +		goto free_pool;
>   
> +	next_desc = first_desc;
>   	cppi5_hdesc_get_obuf(first_desc, &buf_dma, &buf_dma_len);
>   	k3_udma_glue_tx_cppi5_to_dma_addr(tx_chn->tx_chn, &buf_dma);
>   
> @@ -923,6 +941,7 @@ static void am65_cpsw_nuss_xmit_free(struct am65_cpsw_tx_chn *tx_chn,
>   		k3_cppi_desc_pool_free(tx_chn->desc_pool, next_desc);
>   	}
>   
> +free_pool:
>   	k3_cppi_desc_pool_free(tx_chn->desc_pool, first_desc);
>   }
>   
> @@ -932,21 +951,32 @@ static void am65_cpsw_nuss_tx_cleanup(void *data, dma_addr_t desc_dma)
>   	enum am65_cpsw_tx_buf_type buf_type;
>   	struct am65_cpsw_tx_swdata *swdata;
>   	struct cppi5_host_desc_t *desc_tx;
> +	struct xsk_buff_pool *xsk_pool;
>   	struct xdp_frame *xdpf;
>   	struct sk_buff *skb;
>   
>   	desc_tx = k3_cppi_desc_pool_dma2virt(tx_chn->desc_pool, desc_dma);
>   	swdata = cppi5_hdesc_get_swdata(desc_tx);
>   	buf_type = am65_cpsw_nuss_buf_type(tx_chn, desc_dma);
> -	if (buf_type == AM65_CPSW_TX_BUF_TYPE_SKB) {
> +	switch (buf_type) {
> +	case AM65_CPSW_TX_BUF_TYPE_SKB:
>   		skb = swdata->skb;
>   		dev_kfree_skb_any(skb);
> -	} else {
> +		break;
> +	case AM65_CPSW_TX_BUF_TYPE_XDP_TX:
> +	case AM65_CPSW_TX_BUF_TYPE_XDP_NDO:
>   		xdpf = swdata->xdpf;
>   		xdp_return_frame(xdpf);
> +		break;
> +	case AM65_CPSW_TX_BUF_TYPE_XSK_TX:
> +		xsk_pool = swdata->xsk_pool;
> +		xsk_tx_completed(xsk_pool, 1);
> +		break;
> +	default:
> +		break;
>   	}
>   
> -	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
> +	am65_cpsw_nuss_xmit_free(tx_chn, desc_tx, buf_type);
>   }
>   
>   static struct sk_buff *am65_cpsw_build_skb(void *page_addr,
> @@ -1189,6 +1219,82 @@ static int am65_cpsw_nuss_ndo_slave_open(struct net_device *ndev)
>   	return ret;
>   }
>   
> +static int am65_cpsw_xsk_xmit_zc(struct net_device *ndev,
> +				 struct am65_cpsw_tx_chn *tx_chn)
> +{
> +	struct am65_cpsw_common *common = tx_chn->common;
> +	struct xsk_buff_pool *pool = tx_chn->xsk_pool;
> +	struct xdp_desc *xdp_descs = pool->tx_descs;
> +	struct cppi5_host_desc_t *host_desc;
> +	struct am65_cpsw_tx_swdata *swdata;
> +	dma_addr_t dma_desc, dma_buf;
> +	int num_tx = 0, pkt_len;
> +	int descs_avail, ret;
> +	int i;
> +
> +	descs_avail = k3_cppi_desc_pool_avail(tx_chn->desc_pool);
> +	/* ensure that TX ring is not filled up by XDP, always MAX_SKB_FRAGS
> +	 * will be available for normal TX path and queue is stopped there if
> +	 * necessary
> +	 */
> +	if (descs_avail <= MAX_SKB_FRAGS)
> +		return 0;
> +
> +	descs_avail -= MAX_SKB_FRAGS;
> +	descs_avail = xsk_tx_peek_release_desc_batch(pool, descs_avail);
> +
> +	for (i = 0; i < descs_avail; i++) {
> +		host_desc = k3_cppi_desc_pool_alloc(tx_chn->desc_pool);
> +		if (unlikely(!host_desc))
> +			break;
> +
> +		am65_cpsw_nuss_set_buf_type(tx_chn, host_desc,
> +					    AM65_CPSW_TX_BUF_TYPE_XSK_TX);
> +		dma_buf = xsk_buff_raw_get_dma(pool, xdp_descs[i].addr);
> +		pkt_len = xdp_descs[i].len;
> +		xsk_buff_raw_dma_sync_for_device(pool, dma_buf, pkt_len);
> +
> +		cppi5_hdesc_init(host_desc, CPPI5_INFO0_HDESC_EPIB_PRESENT,
> +				 AM65_CPSW_NAV_PS_DATA_SIZE);
> +		cppi5_hdesc_set_pkttype(host_desc, AM65_CPSW_CPPI_TX_PKT_TYPE);
> +		cppi5_hdesc_set_pktlen(host_desc, pkt_len);
> +		cppi5_desc_set_pktids(&host_desc->hdr, 0,
> +				      AM65_CPSW_CPPI_TX_FLOW_ID);
> +		cppi5_desc_set_tags_ids(&host_desc->hdr, 0,
> +					tx_chn->xsk_port_id);
> +
> +		k3_udma_glue_tx_dma_to_cppi5_addr(tx_chn->tx_chn, &dma_buf);
> +		cppi5_hdesc_attach_buf(host_desc, dma_buf, pkt_len, dma_buf,
> +				       pkt_len);
> +
> +		swdata = cppi5_hdesc_get_swdata(host_desc);
> +		swdata->ndev = ndev;
> +		swdata->xsk_pool = pool;
> +
> +		dma_desc = k3_cppi_desc_pool_virt2dma(tx_chn->desc_pool,
> +						      host_desc);
> +		if (AM65_CPSW_IS_CPSW2G(common)) {
> +			ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn,
> +						       host_desc, dma_desc);
> +		} else {
> +			spin_lock_bh(&tx_chn->lock);
> +			ret = k3_udma_glue_push_tx_chn(tx_chn->tx_chn,
> +						       host_desc, dma_desc);
> +			spin_unlock_bh(&tx_chn->lock);
> +		}
> +
> +		if (ret) {
> +			ndev->stats.tx_errors++;
> +			k3_cppi_desc_pool_free(tx_chn->desc_pool, host_desc);
> +			break;
> +		}
> +
> +		num_tx++;
> +	}
> +
> +	return num_tx;
> +}
> +
>   static int am65_cpsw_xdp_tx_frame(struct net_device *ndev,
>   				  struct am65_cpsw_tx_chn *tx_chn,
>   				  struct xdp_frame *xdpf,
> @@ -1716,15 +1822,19 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
>   	struct netdev_queue *netif_txq;
>   	unsigned int total_bytes = 0;
>   	struct net_device *ndev;
> +	int xsk_frames_done = 0;
>   	struct xdp_frame *xdpf;
>   	unsigned int pkt_len;
>   	struct sk_buff *skb;
>   	dma_addr_t desc_dma;
>   	int res, num_tx = 0;
> +	int xsk_tx = 0;
>   
>   	tx_chn = &common->tx_chns[chn];
>   
>   	while (true) {
> +		pkt_len = 0;
> +
>   		if (!single_port)
>   			spin_lock(&tx_chn->lock);
>   		res = k3_udma_glue_pop_tx_chn(tx_chn->tx_chn, &desc_dma);
> @@ -1746,25 +1856,36 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
>   		swdata = cppi5_hdesc_get_swdata(desc_tx);
>   		ndev = swdata->ndev;
>   		buf_type = am65_cpsw_nuss_buf_type(tx_chn, desc_dma);
> -		if (buf_type == AM65_CPSW_TX_BUF_TYPE_SKB) {
> +		switch (buf_type) {
> +		case AM65_CPSW_TX_BUF_TYPE_SKB:
>   			skb = swdata->skb;
>   			am65_cpts_tx_timestamp(tx_chn->common->cpts, skb);
>   			pkt_len = skb->len;
>   			napi_consume_skb(skb, budget);
> -		} else {
> +			total_bytes += pkt_len;
> +			break;
> +		case AM65_CPSW_TX_BUF_TYPE_XDP_TX:
> +		case AM65_CPSW_TX_BUF_TYPE_XDP_NDO:
>   			xdpf = swdata->xdpf;
>   			pkt_len = xdpf->len;
> +			total_bytes += pkt_len;
>   			if (buf_type == AM65_CPSW_TX_BUF_TYPE_XDP_TX)
>   				xdp_return_frame_rx_napi(xdpf);
>   			else
>   				xdp_return_frame(xdpf);
> +			break;
> +		case AM65_CPSW_TX_BUF_TYPE_XSK_TX:
> +			pkt_len = cppi5_hdesc_get_pktlen(desc_tx);
> +			xsk_frames_done++;
> +			break;
> +		default:
> +			break;
>   		}
>   
> -		total_bytes += pkt_len;
>   		num_tx++;
> -		am65_cpsw_nuss_xmit_free(tx_chn, desc_tx);
> +		am65_cpsw_nuss_xmit_free(tx_chn, desc_tx, buf_type);
>   		dev_sw_netstats_tx_add(ndev, 1, pkt_len);
> -		if (!single_port) {
> +		if (!single_port && buf_type != AM65_CPSW_TX_BUF_TYPE_XSK_TX) {
>   			/* as packets from multi ports can be interleaved
>   			 * on the same channel, we have to figure out the
>   			 * port/queue at every packet and report it/wake queue.
> @@ -1781,6 +1902,19 @@ static int am65_cpsw_nuss_tx_compl_packets(struct am65_cpsw_common *common,
>   		am65_cpsw_nuss_tx_wake(tx_chn, ndev, netif_txq);
>   	}
>   
> +	if (tx_chn->xsk_pool) {
> +		if (xsk_frames_done)
> +			xsk_tx_completed(tx_chn->xsk_pool, xsk_frames_done);
> +
> +		if (xsk_uses_need_wakeup(tx_chn->xsk_pool))
> +			xsk_set_tx_need_wakeup(tx_chn->xsk_pool);
> +
> +		ndev = common->ports[tx_chn->xsk_port_id].ndev;

I found that the source of the crash is likely due to ndev being a null 
pointer. This can be proved by adding some print statements, see 
https://gist.github.com/dao-qiu/817e8ee1098a517eab5b2f1b1681382d for my 
print statements and the resulting log.

I noticed that when eth1 is used, the xsk_port_id is 2. I'm assuming 
common->ports[] is 0-indexed so I was wondering if the null pointer may 
be due to indexing beyond the port array size. I'm also assuming 
common->port_num will give the total expected number of ports that is 
possible for indexing common->ports[] but I haven't tried printing it 
out yet.

To test my theory, I modified "ndev = common->ports[tx_chn->xsk_port_id 
- 1].ndev;" to include the tx_chn->xsk_port_id - 1 and the crash appears 
to not happen anymore.

Along the same lines, when eth0 is used and xsk_port_id is 1, would this 
be inadvertently setting the ndev for eth1 instead? When testing eth0, 
the crash does not happen.

Please let me know if you agree if this might be the problem.

> +		netif_txq = netdev_get_tx_queue(ndev, chn);
> +		txq_trans_cond_update(netif_txq);
> +		xsk_tx = am65_cpsw_xsk_xmit_zc(ndev, tx_chn);
> +	}
> +
>   	dev_dbg(dev, "%s:%u pkt:%d\n", __func__, chn, num_tx);
>   
>   	return num_tx;
> @@ -1791,7 +1925,11 @@ static enum hrtimer_restart am65_cpsw_nuss_tx_timer_callback(struct hrtimer *tim
>   	struct am65_cpsw_tx_chn *tx_chns =
>   			container_of(timer, struct am65_cpsw_tx_chn, tx_hrtimer);
>   
> -	enable_irq(tx_chns->irq);
> +	if (tx_chns->irq_disabled) {
> +		tx_chns->irq_disabled = false;
> +		enable_irq(tx_chns->irq);
> +	}
> +
>   	return HRTIMER_NORESTART;
>   }
>   
> @@ -1811,7 +1949,8 @@ static int am65_cpsw_nuss_tx_poll(struct napi_struct *napi_tx, int budget)
>   			hrtimer_start(&tx_chn->tx_hrtimer,
>   				      ns_to_ktime(tx_chn->tx_pace_timeout),
>   				      HRTIMER_MODE_REL_PINNED);
> -		} else {
> +		} else if (tx_chn->irq_disabled) {
> +			tx_chn->irq_disabled = false;
>   			enable_irq(tx_chn->irq);
>   		}
>   	}
> @@ -1834,6 +1973,7 @@ static irqreturn_t am65_cpsw_nuss_tx_irq(int irq, void *dev_id)
>   {
>   	struct am65_cpsw_tx_chn *tx_chn = dev_id;
>   
> +	tx_chn->irq_disabled = true;
>   	disable_irq_nosync(irq);
>   	napi_schedule(&tx_chn->napi_tx);
>   
> @@ -1998,14 +2138,14 @@ static netdev_tx_t am65_cpsw_nuss_ndo_slave_xmit(struct sk_buff *skb,
>   	return NETDEV_TX_OK;
>   
>   err_free_descs:
> -	am65_cpsw_nuss_xmit_free(tx_chn, first_desc);
> +	am65_cpsw_nuss_xmit_free(tx_chn, first_desc, AM65_CPSW_TX_BUF_TYPE_SKB);
>   err_free_skb:
>   	ndev->stats.tx_dropped++;
>   	dev_kfree_skb_any(skb);
>   	return NETDEV_TX_OK;
>   
>   busy_free_descs:
> -	am65_cpsw_nuss_xmit_free(tx_chn, first_desc);
> +	am65_cpsw_nuss_xmit_free(tx_chn, first_desc, AM65_CPSW_TX_BUF_TYPE_SKB);
>   busy_stop_q:
>   	netif_tx_stop_queue(netif_txq);
>   	return NETDEV_TX_BUSY;
> @@ -2259,6 +2399,7 @@ static const struct net_device_ops am65_cpsw_nuss_netdev_ops = {
>   	.ndo_xdp_xmit		= am65_cpsw_ndo_xdp_xmit,
>   	.ndo_hwtstamp_get       = am65_cpsw_nuss_hwtstamp_get,
>   	.ndo_hwtstamp_set       = am65_cpsw_nuss_hwtstamp_set,
> +	.ndo_xsk_wakeup		= am65_cpsw_xsk_wakeup,
>   };
>   
>   static void am65_cpsw_disable_phy(struct phy *phy)
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.h b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> index 2bf4d12f92764706719cc1d65001dbb53da58c38..ac2d9d32e95b932665131a317df8316cb6cb7f96 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h
> @@ -72,6 +72,7 @@ enum am65_cpsw_tx_buf_type {
>   	AM65_CPSW_TX_BUF_TYPE_SKB,
>   	AM65_CPSW_TX_BUF_TYPE_XDP_TX,
>   	AM65_CPSW_TX_BUF_TYPE_XDP_NDO,
> +	AM65_CPSW_TX_BUF_TYPE_XSK_TX,
>   };
>   
>   struct am65_cpsw_host {
> @@ -97,6 +98,9 @@ struct am65_cpsw_tx_chn {
>   	unsigned char dsize_log2;
>   	char tx_chn_name[128];
>   	u32 rate_mbps;
> +	struct xsk_buff_pool *xsk_pool;
> +	int xsk_port_id;
> +	bool irq_disabled;
>   };
>   
>   struct am65_cpsw_rx_flow {
> @@ -118,6 +122,7 @@ struct am65_cpsw_tx_swdata {
>   	union {
>   		struct sk_buff *skb;
>   		struct xdp_frame *xdpf;
> +		struct xsk_buff_pool *xsk_pool;
>   	};
>   };
>   
> diff --git a/drivers/net/ethernet/ti/am65-cpsw-xdp.c b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
> index 0e37c27f77720713430a3e70f6c4b3dfb048cfc0..9adf13056f70fea36d9aeac157b7da0cae2c011e 100644
> --- a/drivers/net/ethernet/ti/am65-cpsw-xdp.c
> +++ b/drivers/net/ethernet/ti/am65-cpsw-xdp.c
> @@ -109,8 +109,10 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
>   	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
>   	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
>   	struct am65_cpsw_rx_flow *rx_flow;
> +	struct am65_cpsw_tx_chn *tx_ch;
>   
>   	rx_flow = &common->rx_chns.flows[qid];
> +	tx_ch = &common->tx_chns[qid];
>   
>   	if (!netif_running(ndev) || !netif_carrier_ok(ndev))
>   		return -ENETDOWN;
> @@ -121,9 +123,16 @@ int am65_cpsw_xsk_wakeup(struct net_device *ndev, u32 qid, u32 flags)
>   	if (qid >= common->rx_ch_num_flows || qid >= common->tx_ch_num)
>   		return -EINVAL;
>   
> -	if (!rx_flow->xsk_pool)
> +	if (!rx_flow->xsk_pool && !tx_ch->xsk_pool)
>   		return -EINVAL;
>   
> +	if (flags & XDP_WAKEUP_TX) {
> +		if (!napi_if_scheduled_mark_missed(&tx_ch->napi_tx)) {
> +			if (likely(napi_schedule_prep(&tx_ch->napi_tx)))
> +				__napi_schedule(&tx_ch->napi_tx);
> +		}
> +	}
> +
>   	if (flags & XDP_WAKEUP_RX) {
>   		if (!napi_if_scheduled_mark_missed(&rx_flow->napi_rx)) {
>   			if (likely(napi_schedule_prep(&rx_flow->napi_rx)))

Best regards,

Daolin

Texas Instruments Sitara MPU Systems Applications

[PATCH net-next v2 6/7] net: ethernet: ti: am65-cpsw: enable zero copy in XDP features

[Roger Quadros]

Now that we have the plumbing in for XDP zero copy RX and TX, enable
the zero copy feature flag.

Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 2e06e7df23ad5249786d081e51434f87dd2a76b5..9d1048eea7e4734873676026906e07babf0345f5 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -3210,7 +3210,8 @@ am65_cpsw_nuss_init_port_ndev(struct am65_cpsw_common *common, u32 port_idx)
 			       NETIF_F_HW_VLAN_CTAG_FILTER;
 	port->ndev->xdp_features = NETDEV_XDP_ACT_BASIC |
 				   NETDEV_XDP_ACT_REDIRECT |
-				   NETDEV_XDP_ACT_NDO_XMIT;
+				   NETDEV_XDP_ACT_NDO_XMIT |
+				   NETDEV_XDP_ACT_XSK_ZEROCOPY;
 	port->ndev->vlan_features |=  NETIF_F_SG;
 	port->ndev->netdev_ops = &am65_cpsw_nuss_netdev_ops;
 	port->ndev->ethtool_ops = &am65_cpsw_ethtool_ops_slave;

-- 
2.34.1

[PATCH net-next v2 7/7] net: ethernet: ti: am65-cpsw: Fix clearing of irq_disabled flag in rx_poll

[Roger Quadros]

In am65_cpsw_nuss_rx_poll() there is a possibility that irq_disabled flag
is cleared but the IRQ is not enabled.

This patch fixes by that by clearing irq_disabled flag right when enabling
the irq.

Fixes: da70d184a8c3 ("net: ethernet: ti: am65-cpsw: Introduce multi queue Rx")
Signed-off-by: Roger Quadros <rogerq@kernel.org>
---
 drivers/net/ethernet/ti/am65-cpsw-nuss.c | 14 ++++++--------
 1 file changed, 6 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 9d1048eea7e4734873676026906e07babf0345f5..c0f891a91d7471364bd4c8b7d82da9967f1753b8 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -1778,15 +1778,13 @@ static int am65_cpsw_nuss_rx_poll(struct napi_struct *napi_rx, int budget)
 	dev_dbg(common->dev, "%s num_rx:%d %d\n", __func__, num_rx, budget);
 
 	if (num_rx < budget && napi_complete_done(napi_rx, num_rx)) {
-		if (flow->irq_disabled) {
+		if (unlikely(flow->rx_pace_timeout)) {
+			hrtimer_start(&flow->rx_hrtimer,
+				      ns_to_ktime(flow->rx_pace_timeout),
+				      HRTIMER_MODE_REL_PINNED);
+		} else if (flow->irq_disabled) {
 			flow->irq_disabled = false;
-			if (unlikely(flow->rx_pace_timeout)) {
-				hrtimer_start(&flow->rx_hrtimer,
-					      ns_to_ktime(flow->rx_pace_timeout),
-					      HRTIMER_MODE_REL_PINNED);
-			} else {
-				enable_irq(flow->irq);
-			}
+			enable_irq(flow->irq);
 		}
 	}
 

-- 
2.34.1

Re: [PATCH net-next v2 7/7] net: ethernet: ti: am65-cpsw: Fix clearing of irq_disabled flag in rx_poll

[Jakub Kicinski]

On Sun, 09 Nov 2025 23:37:57 +0200 Roger Quadros wrote:
> In am65_cpsw_nuss_rx_poll() there is a possibility that irq_disabled flag
> is cleared but the IRQ is not enabled.
> 
> This patch fixes by that by clearing irq_disabled flag right when enabling
> the irq.
> 
> Fixes: da70d184a8c3 ("net: ethernet: ti: am65-cpsw: Introduce multi queue Rx")
> Signed-off-by: Roger Quadros <rogerq@kernel.org>

This looks independent from the series, it needs to go to net.
-- 
pw-bot: cr

Re: [PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[Jakub Kicinski]

On Sun, 09 Nov 2025 23:37:50 +0200 Roger Quadros wrote:
> This series adds AF_XDP zero coppy support to am65-cpsw driver.
> 
> Tests were performed on AM62x-sk with xdpsock application [1].
> 
> A clear improvement is seen in 64 byte packets on Transmit (txonly)
> and receive (rxdrop).
> 1500 byte test seems to be limited by line rate (1G link) so no
> improvement seen there in packet rate. A test on higher speed link
> (or PHY-less setup) might be worthwile.
> 
> There is some issue during l2fwd with 64 byte packets and benchmark
> results show 0. This issue needs to be debugged further.
> A 512 byte l2fwd test result has been added to compare instead.

It appears that the drivers/net/ethernet/ti/am65-* files do not fall
under any MAINTAINERS entry. Please add one or extend the existing CPSW
entry as the first patch of the series.

Re: [PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[Chintan Vankar]

Hello Jakub,

On 12/11/25 06:48, Jakub Kicinski wrote:
> On Sun, 09 Nov 2025 23:37:50 +0200 Roger Quadros wrote:
>> This series adds AF_XDP zero coppy support to am65-cpsw driver.
>>
>> Tests were performed on AM62x-sk with xdpsock application [1].
>>
>> A clear improvement is seen in 64 byte packets on Transmit (txonly)
>> and receive (rxdrop).
>> 1500 byte test seems to be limited by line rate (1G link) so no
>> improvement seen there in packet rate. A test on higher speed link
>> (or PHY-less setup) might be worthwile.
>>
>> There is some issue during l2fwd with 64 byte packets and benchmark
>> results show 0. This issue needs to be debugged further.
>> A 512 byte l2fwd test result has been added to compare instead.
> 
> It appears that the drivers/net/ethernet/ti/am65-* files do not fall
> under any MAINTAINERS entry. Please add one or extend the existing CPSW
> entry as the first patch of the series.
> 

I am mainly working on am65-cpsw-nuss.c driver and volunteering myself
to be the MAINTAINER of am65-cpsw-nuss.c and other CPSW drivers.

Regards,
Chintan.

Re: [EXTERNAL] [PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[Meghana Malladi]

Hi Roger,

On 11/10/25 03:07, Roger Quadros wrote:
> This series adds AF_XDP zero coppy support to am65-cpsw driver. Tests 
> were performed on AM62x-sk with xdpsock application [1]. A clear 
> improvement is seen in 64 byte packets on Transmit (txonly) and receive 
> (rxdrop). 1500 byte test seems to
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> ZjQcmQRYFpfptBannerEnd
> 
> This series adds AF_XDP zero coppy support to am65-cpsw driver.
> 
> Tests were performed on AM62x-sk with xdpsock application [1].
> 
> A clear improvement is seen in 64 byte packets on Transmit (txonly)
> and receive (rxdrop).
> 1500 byte test seems to be limited by line rate (1G link) so no
> improvement seen there in packet rate. A test on higher speed link
> (or PHY-less setup) might be worthwile.
> 
> There is some issue during l2fwd with 64 byte packets and benchmark
> results show 0. This issue needs to be debugged further.
> A 512 byte l2fwd test result has been added to compare instead.
> 
> AF_XDP performance using 64 byte packets in Kpps.
> Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
> rxdrop		322		491		845
> txonly		390		394		723
> l2fwd 		205		257		0
> 
> AF_XDP performance using 512 byte packets in Kpps.
> l2fwd		140		167		231
> 
> AF_XDP performance using 1500 byte packets in Kpps.
> Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
> rxdrop		82		82		82
> txonly		82		82		82
> l2fwd 		82		82		82
> 
> [1]:https://urldefense.com/v3/__https://github.com/xdp-project/bpf-examples/ 
> tree/master/AF_XDP-example__;!!G3vK! 
> SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgb4GkCb$ <https://urldefense.com/v3/__https://github.com/xdp-project/bpf-examples/tree/master/AF_XDP-example__;!!G3vK!SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgb4GkCb$>
> 
> Signed-off-by: Roger Quadros <rogerq@kernel.org>

After applying this series patches, I tried booting am64xx-hsevm in 
prueth dual-emac mode by applying k3-am642-evm-icssg1-dualemac.dtbo 
overlay, and I am getting the following kernel crash: 
https://gist.github.com/MeghanaMalladiTI/784fd2262d95b19fe9573c553c4a6a24

Can you please take a look at this.

> ---
> Changes in v2:
> - Prevent crash on systems with 1 of 2 ports disabled in device tree. check
>    for valid ndev before registering/unregistering XDP RXQ.
>    Reported-by: Meghana Malladi <m-malladi@ti.com>
> - Retain page pool on XDP program exchangae so we don't have to re-alloacate
>    memory.
> - Fix clearing of irq_disabled flag in am65_cpsw_nuss_rx_poll().
> - Link to v1:https://urldefense.com/v3/__https://lore.kernel.org/r/20250520-am65- 
> cpsw-xdp-zc-v1-0-45558024f566@kernel.org__;!!G3vK! 
> SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgAECR9g$ <https://urldefense.com/v3/__https://lore.kernel.org/r/20250520-am65-cpsw-xdp-zc-v1-0-45558024f566@kernel.org__;!!G3vK!SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgAECR9g$>
> 
> ---
> Roger Quadros (7):
>        net: ethernet: ti: am65-cpsw: fix BPF Program change on multi-port CPSW
>        net: ethernet: ti: am65-cpsw: Retain page_pool on XDP program exchange
>        net: ethernet: ti: am65-cpsw: add XSK pool helpers
>        net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for RX
>        net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for TX
>        net: ethernet: ti: am65-cpsw: enable zero copy in XDP features
>        net: ethernet: ti: am65-cpsw: Fix clearing of irq_disabled flag in rx_poll
> 
>   drivers/net/ethernet/ti/Makefile         |   2 +-
>   drivers/net/ethernet/ti/am65-cpsw-nuss.c | 583 ++++++++++++++++++++++++++-----
>   drivers/net/ethernet/ti/am65-cpsw-nuss.h |  37 +-
>   drivers/net/ethernet/ti/am65-cpsw-xdp.c  | 155 ++++++++
>   4 files changed, 692 insertions(+), 85 deletions(-)
> ---
> base-commit: a0c3aefb08cd81864b17c23c25b388dba90b9dad
> change-id: 20250225-am65-cpsw-xdp-zc-2af9e4be1356
> 
> Best regards,
> -- 
> Roger Quadros <rogerq@kernel.org>
> 

Re: [EXTERNAL] [PATCH net-next v2 0/7] net: ethernet: ti: am65-cpsw: add AF_XDP zero copy support

[Meghana Malladi]

Hi Roger,

On 11/10/25 03:07, Roger Quadros wrote:
> This series adds AF_XDP zero coppy support to am65-cpsw driver. Tests 
> were performed on AM62x-sk with xdpsock application [1]. A clear 
> improvement is seen in 64 byte packets on Transmit (txonly) and receive 
> (rxdrop). 1500 byte test seems to
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> 
> This series adds AF_XDP zero coppy support to am65-cpsw driver.
> 
> Tests were performed on AM62x-sk with xdpsock application [1].
> 
> A clear improvement is seen in 64 byte packets on Transmit (txonly)
> and receive (rxdrop).
> 1500 byte test seems to be limited by line rate (1G link) so no
> improvement seen there in packet rate. A test on higher speed link
> (or PHY-less setup) might be worthwile.
> 
> There is some issue during l2fwd with 64 byte packets and benchmark
> results show 0. This issue needs to be debugged further.
> A 512 byte l2fwd test result has been added to compare instead.
> 
> AF_XDP performance using 64 byte packets in Kpps.
> Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
> rxdrop		322		491		845
> txonly		390		394		723
> l2fwd 		205		257		0
> 
> AF_XDP performance using 512 byte packets in Kpps.
> l2fwd		140		167		231
> 
> AF_XDP performance using 1500 byte packets in Kpps.
> Benchmark:	XDP-SKB		XDP-Native	XDP-Native(ZeroCopy)
> rxdrop		82		82		82
> txonly		82		82		82
> l2fwd 		82		82		82
> 
> [1]:https://urldefense.com/v3/__https://github.com/xdp-project/bpf-examples/ 
> tree/master/AF_XDP-example__;!!G3vK! 
> SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgb4GkCb$ <https://urldefense.com/v3/__https://github.com/xdp-project/bpf-examples/tree/master/AF_XDP-example__;!!G3vK!SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgb4GkCb$>
> 
> Signed-off-by: Roger Quadros <rogerq@kernel.org>
> ---

This series causes nfs boot failure for am62lxx-evm:
https://gist.github.com/MeghanaMalladiTI/dda232ebe6c24554e933085513ce8b33

Due to descriptor leakage during Rx teardown. I have faced similar 
problem in ICSSG and a fix similar to this is needed for CPSW as well. 
Please incorporate this fix as well in your v3: 
https://gist.github.com/MeghanaMalladiTI/c5467e2a5c9d4ebdc5e71e3720b6524d

> Changes in v2:
> - Prevent crash on systems with 1 of 2 ports disabled in device tree. check
>    for valid ndev before registering/unregistering XDP RXQ.
>    Reported-by: Meghana Malladi <m-malladi@ti.com>
> - Retain page pool on XDP program exchangae so we don't have to re-alloacate
>    memory.
> - Fix clearing of irq_disabled flag in am65_cpsw_nuss_rx_poll().
> - Link to v1:https://urldefense.com/v3/__https://lore.kernel.org/r/20250520-am65- 
> cpsw-xdp-zc-v1-0-45558024f566@kernel.org__;!!G3vK! 
> SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgAECR9g$ <https://urldefense.com/v3/__https://lore.kernel.org/r/20250520-am65-cpsw-xdp-zc-v1-0-45558024f566@kernel.org__;!!G3vK!SX4J82NfOn_sfwizSTYO-8W3GRuffFIHyCngO1J2CT4Alea18pIGiBI4l5XKFKVUbxESDgAECR9g$>
> 
> ---
> Roger Quadros (7):
>        net: ethernet: ti: am65-cpsw: fix BPF Program change on multi-port CPSW
>        net: ethernet: ti: am65-cpsw: Retain page_pool on XDP program exchange
>        net: ethernet: ti: am65-cpsw: add XSK pool helpers
>        net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for RX
>        net: ethernet: ti: am65-cpsw: Add AF_XDP zero copy for TX
>        net: ethernet: ti: am65-cpsw: enable zero copy in XDP features
>        net: ethernet: ti: am65-cpsw: Fix clearing of irq_disabled flag in rx_poll
> 
>   drivers/net/ethernet/ti/Makefile         |   2 +-
>   drivers/net/ethernet/ti/am65-cpsw-nuss.c | 583 ++++++++++++++++++++++++++-----
>   drivers/net/ethernet/ti/am65-cpsw-nuss.h |  37 +-
>   drivers/net/ethernet/ti/am65-cpsw-xdp.c  | 155 ++++++++
>   4 files changed, 692 insertions(+), 85 deletions(-)
> ---
> base-commit: a0c3aefb08cd81864b17c23c25b388dba90b9dad
> change-id: 20250225-am65-cpsw-xdp-zc-2af9e4be1356
> 
> Best regards,
> -- 
> Roger Quadros <rogerq@kernel.org>
>