[PATCH net-next v7 6/9] net: lan966x: Add support to offload the forwarding.

Horatiu Vultur
2021-12-17T15:53:16Z

This patch adds basic support to offload in the HW the forwarding of the
frames. The driver registers to the switchdev callbacks and implements
the callbacks for attributes SWITCHDEV_ATTR_ID_PORT_STP_STATE and
SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME.
It is not allowed to add a lan966x port to a bridge that contains a
different interface than lan966x.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
---
.../net/ethernet/microchip/lan966x/Kconfig | 1 +
.../net/ethernet/microchip/lan966x/Makefile | 2 +-
.../ethernet/microchip/lan966x/lan966x_main.c | 32 +-
.../ethernet/microchip/lan966x/lan966x_main.h | 9 +
.../microchip/lan966x/lan966x_switchdev.c | 309 ++++++++++++++++++
5 files changed, 351 insertions(+), 2 deletions(-)
create mode 100644 drivers/net/ethernet/microchip/lan966x/lan966x_switchdev.c

diff --git a/drivers/net/ethernet/microchip/lan966x/Kconfig b/drivers/net/ethernet/microchip/lan966x/Kconfig
index 2860a8c9923d..ac273f84b69e 100644
--- a/drivers/net/ethernet/microchip/lan966x/Kconfig
+++ b/drivers/net/ethernet/microchip/lan966x/Kconfig
@@ -2,6 +2,7 @@ config LAN966X_SWITCH
tristate "Lan966x switch driver"
depends on HAS_IOMEM
depends on OF
+ depends on NET_SWITCHDEV
select PHYLINK
select PACKING
help
diff --git a/drivers/net/ethernet/microchip/lan966x/Makefile b/drivers/net/ethernet/microchip/lan966x/Makefile
index 2989ba528236..974229c51f55 100644
--- a/drivers/net/ethernet/microchip/lan966x/Makefile
+++ b/drivers/net/ethernet/microchip/lan966x/Makefile
@@ -6,4 +6,4 @@
obj-$(CONFIG_LAN966X_SWITCH) += lan966x-switch.o

lan966x-switch-objs := lan966x_main.o lan966x_phylink.o lan966x_port.o \
- lan966x_mac.o lan966x_ethtool.o
+ lan966x_mac.o lan966x_ethtool.o lan966x_switchdev.o
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
index dc40ac2eb246..5af60234d81d 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c
@@ -355,6 +355,11 @@ static const struct net_device_ops lan966x_port_netdev_ops = {
.ndo_get_port_parent_id = lan966x_port_get_parent_id,
};

+bool lan966x_netdevice_check(const struct net_device *dev)
+{
+ return dev->netdev_ops == &lan966x_port_netdev_ops;
+}
+
static int lan966x_port_xtr_status(struct lan966x *lan966x, u8 grp)
{
return lan_rd(lan966x, QS_XTR_RD(grp));
@@ -491,6 +496,9 @@ static irqreturn_t lan966x_xtr_irq_handler(int irq, void *args)

skb->protocol = eth_type_trans(skb, dev);

+ if (lan966x->bridge_mask & BIT(src_port))
+ skb->offload_fwd_mark = 1;
+
netif_rx_ni(skb);
dev->stats.rx_bytes += len;
dev->stats.rx_packets++;
@@ -915,6 +923,7 @@ static int lan966x_remove(struct platform_device *pdev)
{
struct lan966x *lan966x = platform_get_drvdata(pdev);

+ lan966x_unregister_notifier_blocks();
lan966x_cleanup_ports(lan966x);

cancel_delayed_work_sync(&lan966x->stats_work);
@@ -934,7 +943,28 @@ static struct platform_driver lan966x_driver = {
.of_match_table = lan966x_match,
},
};
-module_platform_driver(lan966x_driver);
+
+static int __init lan966x_switch_driver_init(void)
+{
+ int ret;
+
+ ret = platform_driver_register(&lan966x_driver);
+ if (ret)
+ return ret;
+
+ lan966x_register_notifier_blocks();
+
+ return 0;
+}
+
+static void __exit lan966x_switch_driver_exit(void)
+{
+ lan966x_unregister_notifier_blocks();
+ platform_driver_unregister(&lan966x_driver);
+}
+
+module_init(lan966x_switch_driver_init);
+module_exit(lan966x_switch_driver_exit);

MODULE_DESCRIPTION("Microchip LAN966X switch driver");
MODULE_AUTHOR("Horatiu Vultur <horatiu.vultur@microchip.com>");
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
index fcd5d09a070c..4723a904c13e 100644
--- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.h
@@ -75,6 +75,10 @@ struct lan966x {

u8 base_mac[ETH_ALEN];

+ struct net_device *bridge;
+ u16 bridge_mask;
+ u16 bridge_fwd_mask;
+
struct list_head mac_entries;
spinlock_t mac_lock; /* lock for mac_entries list */

@@ -122,6 +126,11 @@ extern const struct phylink_mac_ops lan966x_phylink_mac_ops;
extern const struct phylink_pcs_ops lan966x_phylink_pcs_ops;
extern const struct ethtool_ops lan966x_ethtool_ops;

+bool lan966x_netdevice_check(const struct net_device *dev);
+
+void lan966x_register_notifier_blocks(void);
+void lan966x_unregister_notifier_blocks(void);
+
void lan966x_stats_get(struct net_device *dev,
struct rtnl_link_stats64 *stats);
int lan966x_stats_init(struct lan966x *lan966x);
diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_switchdev.c b/drivers/net/ethernet/microchip/lan966x/lan966x_switchdev.c
new file mode 100644
index 000000000000..9db17b677357
--- /dev/null
+++ b/drivers/net/ethernet/microchip/lan966x/lan966x_switchdev.c
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/if_bridge.h>
+#include <net/switchdev.h>
+
+#include "lan966x_main.h"
+
+static struct notifier_block lan966x_netdevice_nb __read_mostly;
+static struct notifier_block lan966x_switchdev_nb __read_mostly;
+static struct notifier_block lan966x_switchdev_blocking_nb __read_mostly;
+
+static void lan966x_update_fwd_mask(struct lan966x *lan966x)
+{
+ int i;
+
+ for (i = 0; i < lan966x->num_phys_ports; i++) {
+ struct lan966x_port *port = lan966x->ports[i];
+ unsigned long mask = 0;
+
+ if (port && lan966x->bridge_fwd_mask & BIT(i))
+ mask = lan966x->bridge_fwd_mask & ~BIT(i);
+
+ mask |= BIT(CPU_PORT);
+
+ lan_wr(ANA_PGID_PGID_SET(mask),
+ lan966x, ANA_PGID(PGID_SRC + i));
+ }
+}
+
+static void lan966x_port_stp_state_set(struct lan966x_port *port, u8 state)
+{
+ struct lan966x *lan966x = port->lan966x;
+ bool learn_ena = false;
+
+ if (state == BR_STATE_FORWARDING || state == BR_STATE_LEARNING)
+ learn_ena = true;
+
+ if (state == BR_STATE_FORWARDING)
+ lan966x->bridge_fwd_mask |= BIT(port->chip_port);
+ else
+ lan966x->bridge_fwd_mask &= ~BIT(port->chip_port);
+
+ lan_rmw(ANA_PORT_CFG_LEARN_ENA_SET(learn_ena),
+ ANA_PORT_CFG_LEARN_ENA,
+ lan966x, ANA_PORT_CFG(port->chip_port));
+
+ lan966x_update_fwd_mask(lan966x);
+}
+
+static void lan966x_port_ageing_set(struct lan966x_port *port,
+ unsigned long ageing_clock_t)
+{
+ unsigned long ageing_jiffies = clock_t_to_jiffies(ageing_clock_t);
+ u32 ageing_time = jiffies_to_msecs(ageing_jiffies) / 1000;
+
+ lan966x_mac_set_ageing(port->lan966x, ageing_time);
+}
+
+static int lan966x_port_attr_set(struct net_device *dev, const void *ctx,
+ const struct switchdev_attr *attr,
+ struct netlink_ext_ack *extack)
+{
+ struct lan966x_port *port = netdev_priv(dev);
+ int err = 0;
+
+ if (ctx && ctx != port)
+ return 0;
+
+ switch (attr->id) {
+ case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
+ lan966x_port_stp_state_set(port, attr->u.stp_state);
+ break;
+ case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
+ lan966x_port_ageing_set(port, attr->u.ageing_time);
+ break;
+ default:
+ err = -EOPNOTSUPP;
+ break;
+ }
+
+ return err;
+}
+
+static int lan966x_port_bridge_join(struct lan966x_port *port,
+ struct net_device *bridge,
+ struct netlink_ext_ack *extack)
+{
+ struct lan966x *lan966x = port->lan966x;
+ struct net_device *dev = port->dev;
+ int err;
+
+ if (!lan966x->bridge_mask) {
+ lan966x->bridge = bridge;
+ } else {
+ if (lan966x->bridge != bridge) {
+ NL_SET_ERR_MSG_MOD(extack, "Not allow to add port to different bridge");
+ return -ENODEV;
+ }
+ }
+
+ err = switchdev_bridge_port_offload(dev, dev, port,
+ &lan966x_switchdev_nb,
+ &lan966x_switchdev_blocking_nb,
+ false, extack);
+ if (err)
+ return err;
+
+ lan966x->bridge_mask |= BIT(port->chip_port);
+
+ return 0;
+}
+
+static void lan966x_port_bridge_leave(struct lan966x_port *port,
+ struct net_device *bridge)
+{
+ struct lan966x *lan966x = port->lan966x;
+
+ lan966x->bridge_mask &= ~BIT(port->chip_port);
+
+ if (!lan966x->bridge_mask)
+ lan966x->bridge = NULL;
+
+ lan966x_mac_cpu_learn(lan966x, port->dev->dev_addr, PORT_PVID);
+}
+
+static int lan966x_port_changeupper(struct net_device *dev,
+ struct netdev_notifier_changeupper_info *info)
+{
+ struct lan966x_port *port = netdev_priv(dev);
+ struct netlink_ext_ack *extack;
+ int err = 0;
+
+ extack = netdev_notifier_info_to_extack(&info->info);
+
+ if (netif_is_bridge_master(info->upper_dev)) {
+ if (info->linking)
+ err = lan966x_port_bridge_join(port, info->upper_dev,
+ extack);
+ else
+ lan966x_port_bridge_leave(port, info->upper_dev);
+ }
+
+ return err;
+}
+
+static int lan966x_port_prechangeupper(struct net_device *dev,
+ struct netdev_notifier_changeupper_info *info)
+{
+ struct lan966x_port *port = netdev_priv(dev);
+
+ if (netif_is_bridge_master(info->upper_dev) && !info->linking)
+ switchdev_bridge_port_unoffload(port->dev, port,
+ &lan966x_switchdev_nb,
+ &lan966x_switchdev_blocking_nb);
+
+ return NOTIFY_DONE;
+}
+
+static int lan966x_foreign_bridging_check(struct net_device *bridge,
+ struct netlink_ext_ack *extack)
+{
+ struct lan966x *lan966x = NULL;
+ bool has_foreign = false;
+ struct net_device *dev;
+ struct list_head *iter;
+
+ if (!netif_is_bridge_master(bridge))
+ return 0;
+
+ netdev_for_each_lower_dev(bridge, dev, iter) {
+ if (lan966x_netdevice_check(dev)) {
+ struct lan966x_port *port = netdev_priv(dev);
+
+ if (lan966x) {
+ /* Bridge already has at least one port of a
+ * lan966x switch inside it, check that it's
+ * the same instance of the driver.
+ */
+ if (port->lan966x != lan966x) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Bridging between multiple lan966x switches disallowed");
+ return -EINVAL;
+ }
+ } else {
+ /* This is the first lan966x port inside this
+ * bridge
+ */
+ lan966x = port->lan966x;
+ }
+ } else {
+ has_foreign = true;
+ }
+
+ if (lan966x && has_foreign) {
+ NL_SET_ERR_MSG_MOD(extack,
+ "Bridging lan966x ports with foreign interfaces disallowed");
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static int lan966x_bridge_check(struct net_device *dev,
+ struct netdev_notifier_changeupper_info *info)
+{
+ return lan966x_foreign_bridging_check(info->upper_dev,
+ info->info.extack);
+}
+
+static int lan966x_netdevice_port_event(struct net_device *dev,
+ struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ int err = 0;
+
+ if (!lan966x_netdevice_check(dev)) {
+ if (event == NETDEV_CHANGEUPPER)
+ return lan966x_bridge_check(dev, ptr);
+ return 0;
+ }
+
+ switch (event) {
+ case NETDEV_PRECHANGEUPPER:
+ err = lan966x_port_prechangeupper(dev, ptr);
+ break;
+ case NETDEV_CHANGEUPPER:
+ err = lan966x_bridge_check(dev, ptr);
+ if (err)
+ return err;
+
+ err = lan966x_port_changeupper(dev, ptr);
+ break;
+ }
+
+ return err;
+}
+
+static int lan966x_netdevice_event(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+ int ret;
+
+ ret = lan966x_netdevice_port_event(dev, nb, event, ptr);
+
+ return notifier_from_errno(ret);
+}
+
+static int lan966x_switchdev_event(struct notifier_block *nb,
+ unsigned long event, void *ptr)
+{
+ struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
+ int err;
+
+ switch (event) {
+ case SWITCHDEV_PORT_ATTR_SET:
+ err = switchdev_handle_port_attr_set(dev, ptr,
+ lan966x_netdevice_check,
+ lan966x_port_attr_set);
+ return notifier_from_errno(err);
+ }
+
+ return NOTIFY_DONE;
+}
+
+static int lan966x_switchdev_blocking_event(struct notifier_block *nb,
+ unsigned long event,
+ void *ptr)
+{
+ struct net_device *dev = switchdev_notifier_info_to_dev(ptr);
+ int err;
+
+ switch (event) {
+ case SWITCHDEV_PORT_ATTR_SET:
+ err = switchdev_handle_port_attr_set(dev, ptr,
+ lan966x_netdevice_check,
+ lan966x_port_attr_set);
+ return notifier_from_errno(err);
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block lan966x_netdevice_nb __read_mostly = {
+ .notifier_call = lan966x_netdevice_event,
+};
+
+static struct notifier_block lan966x_switchdev_nb __read_mostly = {
+ .notifier_call = lan966x_switchdev_event,
+};
+
+static struct notifier_block lan966x_switchdev_blocking_nb __read_mostly = {
+ .notifier_call = lan966x_switchdev_blocking_event,
+};
+
+void lan966x_register_notifier_blocks(void)
+{
+ register_netdevice_notifier(&lan966x_netdevice_nb);
+ register_switchdev_notifier(&lan966x_switchdev_nb);
+ register_switchdev_blocking_notifier(&lan966x_switchdev_blocking_nb);
+}
+
+void lan966x_unregister_notifier_blocks(void)
+{
+ unregister_switchdev_blocking_notifier(&lan966x_switchdev_blocking_nb);
+ unregister_switchdev_notifier(&lan966x_switchdev_nb);
+ unregister_netdevice_notifier(&lan966x_netdevice_nb);
+}
--
2.33.0