net: ti: am65-cpsw-nuss: Add devlink support

AM65 NUSS ethernet switch on K3 devices can be configured to work either
in independent mac mode where each port acts as independent network
interface (multi mac) or switch mode.

Add devlink hooks to provide a way to switch b/w these modes.

Rationale to use devlink instead of defaulting to bridge mode is that
SoC use cases require to support multiple independent MAC ports with no
switching so that users can use software bridges with multi-mac
configuration (e.g: to support LAG, HSR/PRP, etc). Also, switching
between multi mac and switch mode requires significant Port and ALE
reconfiguration, therefore is easier to be made as part of mode change
devlink hooks. It also allows to keep user interface similar to what
was implemented for the previous generation of TI CPSW IP
(on AM33/AM43/AM57 SoCs).

Signed-off-by: Vignesh Raghavendra <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/networking/devlink/am65-nuss-cpsw-switch.rst

···
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================
+am65-cpsw-nuss devlink support
+==============================
+
+This document describes the devlink features implemented by the ``am65-cpsw-nuss``
+device driver.
+
+Parameters
+==========
+
+The ``am65-cpsw-nuss`` driver implements the following driver-specific
+parameters.
+
+.. list-table:: Driver-specific parameters implemented
+   :widths: 5 5 5 85
+
+   * - Name
+     - Type
+     - Mode
+     - Description
+   * - ``switch_mode``
+     - Boolean
+     - runtime
+     - Enable switch mode

Documentation/networking/devlink/index.rst

···
    sja1105
    qed
    ti-cpsw-switch
+   am65-nuss-cpsw-switch

drivers/net/ethernet/ti/Kconfig

···
 config TI_K3_AM65_CPSW_NUSS
 	tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
 	depends on ARCH_K3 && OF && TI_K3_UDMA_GLUE_LAYER
+	select NET_DEVLINK
 	select TI_DAVINCI_MDIO
 	imply PHY_TI_GMII_SEL
 	depends on TI_K3_AM65_CPTS || !TI_K3_AM65_CPTS
···
 
 	  To compile this driver as a module, choose M here: the module
 	  will be called ti-am65-cpsw-nuss.
+
+config TI_K3_AM65_CPSW_SWITCHDEV
+	bool "TI K3 AM654x/J721E CPSW Switch mode support"
+	depends on TI_K3_AM65_CPSW_NUSS
+	depends on NET_SWITCHDEV
+	help
+	 This enables switchdev support for TI K3 CPSWxG Ethernet
+	 Switch. Enable this driver to support hardware switch support for AM65
+	 CPSW NUSS driver.
 
 config TI_K3_AM65_CPTS
 	tristate "TI K3 AM65x CPTS"

drivers/net/ethernet/ti/am65-cpsw-nuss.c

···
 	writel(val, host_p->port_base + AM65_CPSW_PORT_REG_PRI_CTL);
 }
 
+static void am65_cpsw_init_host_port_switch(struct am65_cpsw_common *common);
+static void am65_cpsw_init_host_port_emac(struct am65_cpsw_common *common);
+static void am65_cpsw_init_port_switch_ale(struct am65_cpsw_port *port);
+static void am65_cpsw_init_port_emac_ale(struct am65_cpsw_port *port);
+
 static int am65_cpsw_nuss_common_open(struct am65_cpsw_common *common,
 				      netdev_features_t features)
 {
···
 			     ALE_DEFAULT_THREAD_ID, 0);
 	cpsw_ale_control_set(common->ale, HOST_PORT_NUM,
 			     ALE_DEFAULT_THREAD_ENABLE, 1);
-	if (AM65_CPSW_IS_CPSW2G(common))
-		cpsw_ale_control_set(common->ale, HOST_PORT_NUM,
-				     ALE_PORT_NOLEARN, 1);
 	/* switch to vlan unaware mode */
 	cpsw_ale_control_set(common->ale, HOST_PORT_NUM, ALE_VLAN_AWARE, 1);
 	cpsw_ale_control_set(common->ale, HOST_PORT_NUM,
···
 	cpsw_ale_add_vlan(common->ale, 0, port_mask,
 			  port_mask, port_mask,
 			  port_mask & ~ALE_PORT_HOST);
+
+	if (common->is_emac_mode)
+		am65_cpsw_init_host_port_emac(common);
+	else
+		am65_cpsw_init_host_port_switch(common);
 
 	for (i = 0; i < common->rx_chns.descs_num; i++) {
 		skb = __netdev_alloc_skb_ip_align(NULL,
···
 {
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
-	u32 port_mask;
 	int ret, i;
 
 	ret = pm_runtime_get_sync(common->dev);
···
 
 	am65_cpsw_port_set_sl_mac(port, ndev->dev_addr);
 
-	if (port->slave.mac_only) {
-		/* enable mac-only mode on port */
-		cpsw_ale_control_set(common->ale, port->port_id,
-				     ALE_PORT_MACONLY, 1);
-		cpsw_ale_control_set(common->ale, port->port_id,
-				     ALE_PORT_NOLEARN, 1);
-	}
-
-	port_mask = BIT(port->port_id) | ALE_PORT_HOST;
-	cpsw_ale_add_ucast(common->ale, ndev->dev_addr,
-			   HOST_PORT_NUM, ALE_SECURE, 0);
-	cpsw_ale_add_mcast(common->ale, ndev->broadcast,
-			   port_mask, 0, 0, ALE_MCAST_FWD_2);
+	if (common->is_emac_mode)
+		am65_cpsw_init_port_emac_ale(port);
+	else
+		am65_cpsw_init_port_switch_ale(port);
 
 	/* mac_sl should be configured via phy-link interface */
 	am65_cpsw_sl_ctl_reset(port);
···
 	stats->tx_dropped	= dev->stats.tx_dropped;
 }
 
+static struct devlink_port *am65_cpsw_ndo_get_devlink_port(struct net_device *ndev)
+{
+	struct am65_cpsw_port *port = am65_ndev_to_port(ndev);
+
+	return &port->devlink_port;
+}
+
 static const struct net_device_ops am65_cpsw_nuss_netdev_ops = {
 	.ndo_open		= am65_cpsw_nuss_ndo_slave_open,
 	.ndo_stop		= am65_cpsw_nuss_ndo_slave_stop,
···
 	.ndo_vlan_rx_kill_vid	= am65_cpsw_nuss_ndo_slave_kill_vid,
 	.ndo_do_ioctl		= am65_cpsw_nuss_ndo_slave_ioctl,
 	.ndo_setup_tc           = am65_cpsw_qos_ndo_setup_tc,
+	.ndo_get_devlink_port   = am65_cpsw_ndo_get_devlink_port,
 };
 
 static void am65_cpsw_nuss_slave_disable_unused(struct am65_cpsw_port *port)
···
 	}
 }
 
+static const struct devlink_ops am65_cpsw_devlink_ops = {};
+
+static void am65_cpsw_init_stp_ale_entry(struct am65_cpsw_common *cpsw)
+{
+	cpsw_ale_add_mcast(cpsw->ale, eth_stp_addr, ALE_PORT_HOST, ALE_SUPER, 0,
+			   ALE_MCAST_BLOCK_LEARN_FWD);
+}
+
+static void am65_cpsw_init_host_port_switch(struct am65_cpsw_common *common)
+{
+	struct am65_cpsw_host *host = am65_common_get_host(common);
+
+	writel(common->default_vlan, host->port_base + AM65_CPSW_PORT_VLAN_REG_OFFSET);
+
+	am65_cpsw_init_stp_ale_entry(common);
+
+	cpsw_ale_control_set(common->ale, HOST_PORT_NUM, ALE_P0_UNI_FLOOD, 1);
+	dev_dbg(common->dev, "Set P0_UNI_FLOOD\n");
+	cpsw_ale_control_set(common->ale, HOST_PORT_NUM, ALE_PORT_NOLEARN, 0);
+}
+
+static void am65_cpsw_init_host_port_emac(struct am65_cpsw_common *common)
+{
+	struct am65_cpsw_host *host = am65_common_get_host(common);
+
+	writel(0, host->port_base + AM65_CPSW_PORT_VLAN_REG_OFFSET);
+
+	cpsw_ale_control_set(common->ale, HOST_PORT_NUM, ALE_P0_UNI_FLOOD, 0);
+	dev_dbg(common->dev, "unset P0_UNI_FLOOD\n");
+
+	/* learning make no sense in multi-mac mode */
+	cpsw_ale_control_set(common->ale, HOST_PORT_NUM, ALE_PORT_NOLEARN, 1);
+}
+
+static int am65_cpsw_dl_switch_mode_get(struct devlink *dl, u32 id,
+					struct devlink_param_gset_ctx *ctx)
+{
+	struct am65_cpsw_devlink *dl_priv = devlink_priv(dl);
+	struct am65_cpsw_common *common = dl_priv->common;
+
+	dev_dbg(common->dev, "%s id:%u\n", __func__, id);
+
+	if (id != AM65_CPSW_DL_PARAM_SWITCH_MODE)
+		return -EOPNOTSUPP;
+
+	ctx->val.vbool = !common->is_emac_mode;
+
+	return 0;
+}
+
+static void am65_cpsw_init_port_emac_ale(struct  am65_cpsw_port *port)
+{
+	struct am65_cpsw_slave_data *slave = &port->slave;
+	struct am65_cpsw_common *common = port->common;
+	u32 port_mask;
+
+	writel(slave->port_vlan, port->port_base + AM65_CPSW_PORT_VLAN_REG_OFFSET);
+
+	if (slave->mac_only)
+		/* enable mac-only mode on port */
+		cpsw_ale_control_set(common->ale, port->port_id,
+				     ALE_PORT_MACONLY, 1);
+
+	cpsw_ale_control_set(common->ale, port->port_id, ALE_PORT_NOLEARN, 1);
+
+	port_mask = BIT(port->port_id) | ALE_PORT_HOST;
+
+	cpsw_ale_add_ucast(common->ale, port->ndev->dev_addr,
+			   HOST_PORT_NUM, ALE_SECURE, slave->port_vlan);
+	cpsw_ale_add_mcast(common->ale, port->ndev->broadcast,
+			   port_mask, ALE_VLAN, slave->port_vlan, ALE_MCAST_FWD_2);
+}
+
+static void am65_cpsw_init_port_switch_ale(struct am65_cpsw_port *port)
+{
+	struct am65_cpsw_slave_data *slave = &port->slave;
+	struct am65_cpsw_common *cpsw = port->common;
+	u32 port_mask;
+
+	cpsw_ale_control_set(cpsw->ale, port->port_id,
+			     ALE_PORT_NOLEARN, 0);
+
+	cpsw_ale_add_ucast(cpsw->ale, port->ndev->dev_addr,
+			   HOST_PORT_NUM, ALE_SECURE | ALE_BLOCKED | ALE_VLAN,
+			   slave->port_vlan);
+
+	port_mask = BIT(port->port_id) | ALE_PORT_HOST;
+
+	cpsw_ale_add_mcast(cpsw->ale, port->ndev->broadcast,
+			   port_mask, ALE_VLAN, slave->port_vlan,
+			   ALE_MCAST_FWD_2);
+
+	writel(slave->port_vlan, port->port_base + AM65_CPSW_PORT_VLAN_REG_OFFSET);
+
+	cpsw_ale_control_set(cpsw->ale, port->port_id,
+			     ALE_PORT_MACONLY, 0);
+}
+
+static int am65_cpsw_dl_switch_mode_set(struct devlink *dl, u32 id,
+					struct devlink_param_gset_ctx *ctx)
+{
+	struct am65_cpsw_devlink *dl_priv = devlink_priv(dl);
+	struct am65_cpsw_common *cpsw = dl_priv->common;
+	bool switch_en = ctx->val.vbool;
+	bool if_running = false;
+	int i;
+
+	dev_dbg(cpsw->dev, "%s id:%u\n", __func__, id);
+
+	if (id != AM65_CPSW_DL_PARAM_SWITCH_MODE)
+		return -EOPNOTSUPP;
+
+	if (switch_en == !cpsw->is_emac_mode)
+		return 0;
+
+	if (!switch_en && cpsw->br_members) {
+		dev_err(cpsw->dev, "Remove ports from bridge before disabling switch mode\n");
+		return -EINVAL;
+	}
+
+	rtnl_lock();
+
+	cpsw->is_emac_mode = !switch_en;
+
+	for (i = 0; i < cpsw->port_num; i++) {
+		struct net_device *sl_ndev = cpsw->ports[i].ndev;
+
+		if (!sl_ndev || !netif_running(sl_ndev))
+			continue;
+
+		if_running = true;
+	}
+
+	if (!if_running) {
+		/* all ndevs are down */
+		for (i = 0; i < cpsw->port_num; i++) {
+			struct net_device *sl_ndev = cpsw->ports[i].ndev;
+			struct am65_cpsw_slave_data *slave;
+
+			if (!sl_ndev)
+				continue;
+
+			slave = am65_ndev_to_slave(sl_ndev);
+			if (switch_en)
+				slave->port_vlan = cpsw->default_vlan;
+			else
+				slave->port_vlan = 0;
+		}
+
+		goto exit;
+	}
+
+	cpsw_ale_control_set(cpsw->ale, 0, ALE_BYPASS, 1);
+	/* clean up ALE table */
+	cpsw_ale_control_set(cpsw->ale, HOST_PORT_NUM, ALE_CLEAR, 1);
+	cpsw_ale_control_get(cpsw->ale, HOST_PORT_NUM, ALE_AGEOUT);
+
+	if (switch_en) {
+		dev_info(cpsw->dev, "Enable switch mode\n");
+
+		am65_cpsw_init_host_port_switch(cpsw);
+
+		for (i = 0; i < cpsw->port_num; i++) {
+			struct net_device *sl_ndev = cpsw->ports[i].ndev;
+			struct am65_cpsw_slave_data *slave;
+			struct am65_cpsw_port *port;
+
+			if (!sl_ndev)
+				continue;
+
+			port = am65_ndev_to_port(sl_ndev);
+			slave = am65_ndev_to_slave(sl_ndev);
+			slave->port_vlan = cpsw->default_vlan;
+
+			if (netif_running(sl_ndev))
+				am65_cpsw_init_port_switch_ale(port);
+		}
+
+	} else {
+		dev_info(cpsw->dev, "Disable switch mode\n");
+
+		am65_cpsw_init_host_port_emac(cpsw);
+
+		for (i = 0; i < cpsw->port_num; i++) {
+			struct net_device *sl_ndev = cpsw->ports[i].ndev;
+			struct am65_cpsw_port *port;
+
+			if (!sl_ndev)
+				continue;
+
+			port = am65_ndev_to_port(sl_ndev);
+			port->slave.port_vlan = 0;
+			if (netif_running(sl_ndev))
+				am65_cpsw_init_port_emac_ale(port);
+		}
+	}
+	cpsw_ale_control_set(cpsw->ale, HOST_PORT_NUM, ALE_BYPASS, 0);
+exit:
+	rtnl_unlock();
+
+	return 0;
+}
+
+static const struct devlink_param am65_cpsw_devlink_params[] = {
+	DEVLINK_PARAM_DRIVER(AM65_CPSW_DL_PARAM_SWITCH_MODE, "switch_mode",
+			     DEVLINK_PARAM_TYPE_BOOL,
+			     BIT(DEVLINK_PARAM_CMODE_RUNTIME),
+			     am65_cpsw_dl_switch_mode_get,
+			     am65_cpsw_dl_switch_mode_set, NULL),
+};
+
+static void am65_cpsw_unregister_devlink_ports(struct am65_cpsw_common *common)
+{
+	struct devlink_port *dl_port;
+	struct am65_cpsw_port *port;
+	int i;
+
+	for (i = 1; i <= common->port_num; i++) {
+		port = am65_common_get_port(common, i);
+		dl_port = &port->devlink_port;
+
+		if (dl_port->registered)
+			devlink_port_unregister(dl_port);
+	}
+}
+
+static int am65_cpsw_nuss_register_devlink(struct am65_cpsw_common *common)
+{
+	struct devlink_port_attrs attrs = {};
+	struct am65_cpsw_devlink *dl_priv;
+	struct device *dev = common->dev;
+	struct devlink_port *dl_port;
+	struct am65_cpsw_port *port;
+	int ret = 0;
+	int i;
+
+	common->devlink =
+		devlink_alloc(&am65_cpsw_devlink_ops, sizeof(*dl_priv));
+	if (!common->devlink)
+		return -ENOMEM;
+
+	dl_priv = devlink_priv(common->devlink);
+	dl_priv->common = common;
+
+	ret = devlink_register(common->devlink, dev);
+	if (ret) {
+		dev_err(dev, "devlink reg fail ret:%d\n", ret);
+		goto dl_free;
+	}
+
+	/* Provide devlink hook to switch mode when multiple external ports
+	 * are present NUSS switchdev driver is enabled.
+	 */
+	if (!AM65_CPSW_IS_CPSW2G(common) &&
+	    IS_ENABLED(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV)) {
+		ret = devlink_params_register(common->devlink,
+					      am65_cpsw_devlink_params,
+					      ARRAY_SIZE(am65_cpsw_devlink_params));
+		if (ret) {
+			dev_err(dev, "devlink params reg fail ret:%d\n", ret);
+			goto dl_unreg;
+		}
+		devlink_params_publish(common->devlink);
+	}
+
+	for (i = 1; i <= common->port_num; i++) {
+		port = am65_common_get_port(common, i);
+		dl_port = &port->devlink_port;
+
+		attrs.flavour = DEVLINK_PORT_FLAVOUR_PHYSICAL;
+		attrs.phys.port_number = port->port_id;
+		attrs.switch_id.id_len = sizeof(resource_size_t);
+		memcpy(attrs.switch_id.id, common->switch_id, attrs.switch_id.id_len);
+		devlink_port_attrs_set(dl_port, &attrs);
+
+		ret = devlink_port_register(common->devlink, dl_port, port->port_id);
+		if (ret) {
+			dev_err(dev, "devlink_port reg fail for port %d, ret:%d\n",
+				port->port_id, ret);
+			goto dl_port_unreg;
+		}
+		devlink_port_type_eth_set(dl_port, port->ndev);
+	}
+
+	return ret;
+
+dl_port_unreg:
+	am65_cpsw_unregister_devlink_ports(common);
+dl_unreg:
+	devlink_unregister(common->devlink);
+dl_free:
+	devlink_free(common->devlink);
+
+	return ret;
+}
+
+static void am65_cpsw_unregister_devlink(struct am65_cpsw_common *common)
+{
+	if (!AM65_CPSW_IS_CPSW2G(common) &&
+	    IS_ENABLED(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV)) {
+		devlink_params_unpublish(common->devlink);
+		devlink_params_unregister(common->devlink, am65_cpsw_devlink_params,
+					  ARRAY_SIZE(am65_cpsw_devlink_params));
+	}
+
+	am65_cpsw_unregister_devlink_ports(common);
+	devlink_unregister(common->devlink);
+	devlink_free(common->devlink);
+}
+
 static int am65_cpsw_nuss_register_ndevs(struct am65_cpsw_common *common)
 {
 	struct device *dev = common->dev;
···
 		}
 	}
 
+	ret = am65_cpsw_nuss_register_devlink(common);
+	if (ret)
+		goto err_cleanup_ndev;
 
 	/* can't auto unregister ndev using devm_add_action() due to
 	 * devres release sequence in DD core for DMA
 	 */
-	return 0;
 
+	return 0;
 err_cleanup_ndev:
 	am65_cpsw_nuss_cleanup_ndev(common);
 	return ret;
···
 	struct device_node *node;
 	struct resource *res;
 	struct clk *clk;
+	u64 id_temp;
 	int ret, i;
 
 	common = devm_kzalloc(dev, sizeof(struct am65_cpsw_common), GFP_KERNEL);
···
 	if (IS_ERR(common->ss_base))
 		return PTR_ERR(common->ss_base);
 	common->cpsw_base = common->ss_base + AM65_CPSW_CPSW_NU_BASE;
+	/* Use device's physical base address as switch id */
+	id_temp = cpu_to_be64(res->start);
+	memcpy(common->switch_id, &id_temp, sizeof(res->start));
 
 	node = of_get_child_by_name(dev->of_node, "ethernet-ports");
 	if (!node)
···
 	init_completion(&common->tdown_complete);
 	common->tx_ch_num = 1;
 	common->pf_p0_rx_ptype_rrobin = false;
+	common->default_vlan = 1;
 
 	common->ports = devm_kcalloc(dev, common->port_num,
 				     sizeof(*common->ports),
···
 
 	dev_set_drvdata(dev, common);
 
+	common->is_emac_mode = true;
+
 	ret = am65_cpsw_nuss_init_ndevs(common);
 	if (ret)
 		goto err_of_clear;
···
 		pm_runtime_put_noidle(&pdev->dev);
 		return ret;
 	}
+
+	am65_cpsw_unregister_devlink(common);
 
 	/* must unregister ndevs here because DD release_driver routine calls
 	 * dma_deconfigure(dev) before devres_release_all(dev)

drivers/net/ethernet/ti/am65-cpsw-nuss.h

···
 #ifndef AM65_CPSW_NUSS_H_
 #define AM65_CPSW_NUSS_H_
 
+#include <linux/if_ether.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/netdevice.h>
 #include <linux/phy.h>
 #include <linux/platform_device.h>
 #include <linux/soc/ti/k3-ringacc.h>
+#include <net/devlink.h>
 #include "am65-cpsw-qos.h"
 
 struct am65_cpts;
···
 #define AM65_CPSW_MAX_TX_QUEUES	8
 #define AM65_CPSW_MAX_RX_QUEUES	1
 #define AM65_CPSW_MAX_RX_FLOWS	1
+
+#define AM65_CPSW_PORT_VLAN_REG_OFFSET	0x014
 
 struct am65_cpsw_slave_data {
 	bool				mac_only;
···
 	bool				rx_pause;
 	bool				tx_pause;
 	u8				mac_addr[ETH_ALEN];
+	int				port_vlan;
 };
 
 struct am65_cpsw_port {
···
 	bool				tx_ts_enabled;
 	bool				rx_ts_enabled;
 	struct am65_cpsw_qos		qos;
+	struct devlink_port		devlink_port;
 };
 
 struct am65_cpsw_host {
···
 	const char	*ale_dev_id;
 };
 
+enum cpsw_devlink_param_id {
+	AM65_CPSW_DEVLINK_PARAM_ID_BASE = DEVLINK_PARAM_GENERIC_ID_MAX,
+	AM65_CPSW_DL_PARAM_SWITCH_MODE,
+};
+
+struct am65_cpsw_devlink {
+	struct am65_cpsw_common *common;
+};
+
 struct am65_cpsw_common {
 	struct device		*dev;
 	struct device		*mdio_dev;
···
 	bool			pf_p0_rx_ptype_rrobin;
 	struct am65_cpts	*cpts;
 	int			est_enabled;
+
+	bool		is_emac_mode;
+	u16			br_members;
+	int			default_vlan;
+	struct devlink *devlink;
+	unsigned char switch_id[MAX_PHYS_ITEM_ID_LEN];
 };
 
 struct am65_cpsw_ndev_stats {
···
 	u32			msg_enable;
 	struct am65_cpsw_port	*port;
 	struct am65_cpsw_ndev_stats __percpu *stats;
+	bool offload_fwd_mark;
 };
 
 #define am65_ndev_to_priv(ndev) \