After this change the MTIP L2 switch can be configured as offloading
device for packet switching when bridge on its interfaces is created.
Signed-off-by: Lukasz Majewski <lukasz.majewski@mailbox.org>
---
Changes for v13:
- New patch - created by excluding some code from large (i.e. v12 and
earlier) MTIP driver
Changes for v14 - v15:
- None
Changes for v16:
- Enable MTIP ports to support bridge offloading
Changes for v17 - v20:
- None
---
.../net/ethernet/freescale/mtipsw/Makefile | 2 +-
.../net/ethernet/freescale/mtipsw/mtipl2sw.c | 9 +-
.../net/ethernet/freescale/mtipsw/mtipl2sw.h | 2 +
.../ethernet/freescale/mtipsw/mtipl2sw_br.c | 132 ++++++++++++++++++
4 files changed, 143 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
diff --git a/drivers/net/ethernet/freescale/mtipsw/Makefile b/drivers/net/ethernet/freescale/mtipsw/Makefile
index a99aaf6ddfb2..81e2b0e03e6c 100644
--- a/drivers/net/ethernet/freescale/mtipsw/Makefile
+++ b/drivers/net/ethernet/freescale/mtipsw/Makefile
@@ -1,4 +1,4 @@
# SPDX-License-Identifier: GPL-2.0
obj-$(CONFIG_FEC_MTIP_L2SW) += nxp-mtipl2sw.o
-nxp-mtipl2sw-objs := mtipl2sw.o mtipl2sw_mgnt.o
+nxp-mtipl2sw-objs := mtipl2sw.o mtipl2sw_mgnt.o mtipl2sw_br.o
diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c
index 1a2722a4938b..32cdc3f0bf47 100644
--- a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c
+++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.c
@@ -1922,11 +1922,15 @@ static int mtip_sw_probe(struct platform_device *pdev)
if (ret)
return dev_err_probe(&pdev->dev, ret, "Could not alloc IRQ\n");
+ ret = mtip_register_notifiers(fep);
+ if (ret)
+ return ret;
+
ret = mtip_switch_dma_init(fep);
if (ret) {
dev_err(&pdev->dev, "%s: ethernet switch init fail (%d)!\n",
__func__, ret);
- return ret;
+ goto unregister_notifiers;
}
ret = mtip_mii_init(fep, pdev);
@@ -1957,6 +1961,8 @@ static int mtip_sw_probe(struct platform_device *pdev)
fep->bd_dma);
fep->rx_bd_base = NULL;
fep->tx_bd_base = NULL;
+ unregister_notifiers:
+ mtip_unregister_notifiers(fep);
return ret;
}
@@ -1965,6 +1971,7 @@ static void mtip_sw_remove(struct platform_device *pdev)
{
struct switch_enet_private *fep = platform_get_drvdata(pdev);
+ mtip_unregister_notifiers(fep);
mtip_ndev_cleanup(fep);
mtip_mii_remove(fep);
diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.h b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.h
index 4054415d39f9..449eca41e6b6 100644
--- a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.h
+++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw.h
@@ -640,6 +640,8 @@ int mtip_port_learning_config(struct switch_enet_private *fep, int port,
int mtip_port_blocking_config(struct switch_enet_private *fep, int port,
bool enable);
bool mtip_is_switch_netdev_port(const struct net_device *ndev);
+int mtip_register_notifiers(struct switch_enet_private *fep);
+void mtip_unregister_notifiers(struct switch_enet_private *fep);
int mtip_port_enable_config(struct switch_enet_private *fep, int port,
bool tx_en, bool rx_en);
void mtip_clear_atable(struct switch_enet_private *fep);
diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
new file mode 100644
index 000000000000..f961b9cc4e6a
--- /dev/null
+++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
@@ -0,0 +1,132 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * L2 switch Controller driver for MTIP block - bridge network interface
+ *
+ * Copyright (C) 2025 DENX Software Engineering GmbH
+ * Lukasz Majewski <lukma@denx.de>
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/netdevice.h>
+#include <linux/platform_device.h>
+#include <net/switchdev.h>
+
+#include "mtipl2sw.h"
+
+static int mtip_ndev_port_link(struct net_device *ndev,
+ struct net_device *br_ndev,
+ struct netlink_ext_ack *extack)
+{
+ struct mtip_ndev_priv *priv = netdev_priv(ndev), *other_priv;
+ struct switch_enet_private *fep = priv->fep;
+ struct net_device *other_ndev;
+ int err;
+
+ /* Check if one port of MTIP switch is already bridged */
+ if (fep->br_members && !fep->br_offload) {
+ /* Get the second bridge ndev */
+ other_ndev = fep->ndev[fep->br_members - 1];
+ other_priv = netdev_priv(other_ndev);
+ if (other_priv->master_dev != br_ndev) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "L2 offloading only possible for the same bridge!");
+ return notifier_from_errno(-EOPNOTSUPP);
+ }
+
+ fep->br_offload = 1;
+ mtip_switch_dis_port_separation(fep);
+ mtip_clear_atable(fep);
+ }
+
+ if (!priv->master_dev)
+ priv->master_dev = br_ndev;
+
+ fep->br_members |= BIT(priv->portnum - 1);
+
+ err = switchdev_bridge_port_offload(ndev, ndev, NULL, NULL, NULL,
+ false, extack);
+ if (err) {
+ dev_err(&ndev->dev, "can't offload bridge port %s [err: %d]\n",
+ ndev->name, err);
+ return err;
+ }
+
+ dev_dbg(&ndev->dev,
+ "%s: ndev: %s br: %s fep: %p members: 0x%x offload: %d\n",
+ __func__, ndev->name, br_ndev->name, fep, fep->br_members,
+ fep->br_offload);
+
+ return NOTIFY_DONE;
+}
+
+static void mtip_netdevice_port_unlink(struct net_device *ndev)
+{
+ struct mtip_ndev_priv *priv = netdev_priv(ndev);
+ struct switch_enet_private *fep = priv->fep;
+
+ dev_dbg(&ndev->dev, "%s: ndev: %s members: 0x%x\n", __func__,
+ ndev->name, fep->br_members);
+
+ switchdev_bridge_port_unoffload(ndev, NULL, NULL, NULL);
+
+ fep->br_members &= ~BIT(priv->portnum - 1);
+ priv->master_dev = NULL;
+
+ if (fep->br_members && fep->br_offload) {
+ fep->br_offload = 0;
+ mtip_switch_en_port_separation(fep);
+ mtip_clear_atable(fep);
+ }
+}
+
+/* netdev notifier */
+static int mtip_netdevice_event(struct notifier_block *unused,
+ unsigned long event, void *ptr)
+{
+ struct net_device *ndev = netdev_notifier_info_to_dev(ptr);
+ struct netdev_notifier_changeupper_info *info = ptr;
+ struct netlink_ext_ack *extack;
+ int ret = NOTIFY_DONE;
+
+ if (!mtip_is_switch_netdev_port(ndev))
+ return NOTIFY_DONE;
+
+ extack = netdev_notifier_info_to_extack(&info->info);
+
+ switch (event) {
+ case NETDEV_CHANGEUPPER:
+ if (!netif_is_bridge_master(info->upper_dev))
+ break;
+
+ if (info->linking)
+ ret = mtip_ndev_port_link(ndev, info->upper_dev,
+ extack);
+ else
+ mtip_netdevice_port_unlink(ndev);
+
+ break;
+ default:
+ return NOTIFY_DONE;
+ }
+
+ return notifier_from_errno(ret);
+}
+
+static struct notifier_block mtip_netdevice_nb __read_mostly = {
+ .notifier_call = mtip_netdevice_event,
+};
+
+int mtip_register_notifiers(struct switch_enet_private *fep)
+{
+ int ret = register_netdevice_notifier(&mtip_netdevice_nb);
+
+ if (ret)
+ dev_err(&fep->pdev->dev, "can't register netdevice notifier\n");
+
+ return ret;
+}
+
+void mtip_unregister_notifiers(struct switch_enet_private *fep)
+{
+ unregister_netdevice_notifier(&mtip_netdevice_nb);
+}
--
2.39.5This is an AI-generated review of your patch. The human sending this
email has considered the AI review valid, or at least plausible.
For local reproduction steps see https://netdev-ai.bots.linux.dev/ai-local.html
---
net: mtip: Extend the L2 switch driver for imx287 with bridge operations
This patch adds bridge operations support to the MTIP L2 switch driver,
enabling hardware offloading for packet switching when a bridge is
created on the switch interfaces.
> diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
> new file mode 100644
> index 000000000000..f961b9cc4e6a
> --- /dev/null
> +++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
[ ... ]
> +static int mtip_ndev_port_link(struct net_device *ndev,
> + struct net_device *br_ndev,
> + struct netlink_ext_ack *extack)
> +{
> + struct mtip_ndev_priv *priv = netdev_priv(ndev), *other_priv;
> + struct switch_enet_private *fep = priv->fep;
> + struct net_device *other_ndev;
> + int err;
> +
> + /* Check if one port of MTIP switch is already bridged */
> + if (fep->br_members && !fep->br_offload) {
> + /* Get the second bridge ndev */
> + other_ndev = fep->ndev[fep->br_members - 1];
> + other_priv = netdev_priv(other_ndev);
> + if (other_priv->master_dev != br_ndev) {
> + NL_SET_ERR_MSG_MOD(extack,
> + "L2 offloading only possible for the same bridge!");
> + return notifier_from_errno(-EOPNOTSUPP);
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Should this return -EOPNOTSUPP instead of notifier_from_errno(-EOPNOTSUPP)?
The caller mtip_netdevice_event() already wraps the return value with
notifier_from_errno(ret), so double-wrapping corrupts the return value.
Looking at similar drivers like cpsw_new.c (cpsw_netdevice_port_link),
the pattern is to return raw errno values here and let the event handler
do the conversion.
> + }
> +
> + fep->br_offload = 1;
> + mtip_switch_dis_port_separation(fep);
> + mtip_clear_atable(fep);
> + }
> +
> + if (!priv->master_dev)
> + priv->master_dev = br_ndev;
> +
> + fep->br_members |= BIT(priv->portnum - 1);
> +
> + err = switchdev_bridge_port_offload(ndev, ndev, NULL, NULL, NULL,
> + false, extack);
> + if (err) {
> + dev_err(&ndev->dev, "can't offload bridge port %s [err: %d]\n",
> + ndev->name, err);
> + return err;
> + }
If switchdev_bridge_port_offload() fails, the state changes made earlier
in the function (br_offload, br_members, master_dev, and the hardware
configuration via mtip_switch_dis_port_separation and mtip_clear_atable)
are not rolled back.
Looking at cpsw_new.c for reference, it modifies br_members after the
switchdev call succeeds, avoiding the need for rollback. Could the state
updates here be reordered to happen after switchdev_bridge_port_offload()
returns successfully?
[ ... ]
> +static int mtip_netdevice_event(struct notifier_block *unused,
> + unsigned long event, void *ptr)
> +{
[ ... ]
> + return notifier_from_errno(ret);
> +}
[ ... ]
Hi Jakub,
> This is an AI-generated review of your patch. The human sending this
> email has considered the AI review valid, or at least plausible.
>
> For local reproduction steps see
> https://netdev-ai.bots.linux.dev/ai-local.html ---
> net: mtip: Extend the L2 switch driver for imx287 with bridge
> operations
>
> This patch adds bridge operations support to the MTIP L2 switch
> driver, enabling hardware offloading for packet switching when a
> bridge is created on the switch interfaces.
>
> > diff --git a/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
> > b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c new file mode
> > 100644 index 000000000000..f961b9cc4e6a
> > --- /dev/null
> > +++ b/drivers/net/ethernet/freescale/mtipsw/mtipl2sw_br.c
>
> [ ... ]
>
> > +static int mtip_ndev_port_link(struct net_device *ndev,
> > + struct net_device *br_ndev,
> > + struct netlink_ext_ack *extack)
> > +{
> > + struct mtip_ndev_priv *priv = netdev_priv(ndev),
> > *other_priv;
> > + struct switch_enet_private *fep = priv->fep;
> > + struct net_device *other_ndev;
> > + int err;
> > +
> > + /* Check if one port of MTIP switch is already bridged */
> > + if (fep->br_members && !fep->br_offload) {
> > + /* Get the second bridge ndev */
> > + other_ndev = fep->ndev[fep->br_members - 1];
> > + other_priv = netdev_priv(other_ndev);
> > + if (other_priv->master_dev != br_ndev) {
> > + NL_SET_ERR_MSG_MOD(extack,
> > + "L2 offloading only
> > possible for the same bridge!");
> > + return notifier_from_errno(-EOPNOTSUPP);
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
> Should this return -EOPNOTSUPP instead of
> notifier_from_errno(-EOPNOTSUPP)? The caller mtip_netdevice_event()
> already wraps the return value with notifier_from_errno(ret), so
> double-wrapping corrupts the return value.
>
> Looking at similar drivers like cpsw_new.c (cpsw_netdevice_port_link),
> the pattern is to return raw errno values here and let the event
> handler do the conversion.
>
Yes, the call to notifier_from_errno() can be removed.
I will fix it with v21.
> > + }
> > +
> > + fep->br_offload = 1;
> > + mtip_switch_dis_port_separation(fep);
> > + mtip_clear_atable(fep);
> > + }
> > +
> > + if (!priv->master_dev)
> > + priv->master_dev = br_ndev;
> > +
> > + fep->br_members |= BIT(priv->portnum - 1);
> > +
> > + err = switchdev_bridge_port_offload(ndev, ndev, NULL,
> > NULL, NULL,
> > + false, extack);
> > + if (err) {
> > + dev_err(&ndev->dev, "can't offload bridge port %s
> > [err: %d]\n",
> > + ndev->name, err);
> > + return err;
> > + }
>
> If switchdev_bridge_port_offload() fails, the state changes made
> earlier in the function (br_offload, br_members, master_dev, and the
> hardware configuration via mtip_switch_dis_port_separation and
> mtip_clear_atable) are not rolled back.
>
> Looking at cpsw_new.c for reference, it modifies br_members after the
> switchdev call succeeds, avoiding the need for rollback. Could the
> state updates here be reordered to happen after
> switchdev_bridge_port_offload() returns successfully?
>
I will add to v21:
fep->br_members &= ~BIT(priv->portnum - 1);
priv->master_dev = NULL;
before I return err.
(This "rollback" code was missing).
> [ ... ]
>
> > +static int mtip_netdevice_event(struct notifier_block *unused,
> > + unsigned long event, void *ptr)
> > +{
>
> [ ... ]
>
> > + return notifier_from_errno(ret);
> > +}
>
> [ ... ]
--
Best regards,
Łukasz Majewski
© 2016 - 2026 Red Hat, Inc.