[PATCH v1 1/3] net: dsa: Add global forwarding mode support

[PATCH v1 1/3] net: dsa: Add global forwarding mode support

[Oleksij Rempel]

This patch introduces a global forwarding mode control for DSA switches
in Barebox.  It adds a new `forwarding` parameter that allows enabling
or disabling forwarding  between all ports on a DSA switch.

This enables users to configure global forwarding dynamically via:
dev.switch0.forwarding=1  # Enable forwarding
dev.switch0.forwarding=0  # Disable forwarding (isolated mode)

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 drivers/net/dsa.c | 12 ++++++++++++
 include/dsa.h     |  4 ++++
 2 files changed, 16 insertions(+)

diff --git a/drivers/net/dsa.c b/drivers/net/dsa.c
index a451a1a35e8b..537e9dd72ac6 100644
--- a/drivers/net/dsa.c
+++ b/drivers/net/dsa.c
@@ -4,6 +4,7 @@
 #include <dma.h>
 #include <dsa.h>
 #include <of_net.h>
+#include <param.h>
 
 u32 dsa_user_ports(struct dsa_switch *ds)
 {
@@ -431,6 +432,13 @@ static int dsa_switch_parse_ports_of(struct dsa_switch *ds,
 	return ret;
 }
 
+static int dsa_set_forwarding(struct param_d *p, void *priv)
+{
+	struct dsa_switch *ds = priv;
+
+	return ds->ops->set_forwarding(ds, ds->forwarding_enable);
+}
+
 int dsa_register_switch(struct dsa_switch *ds)
 {
 	int ret;
@@ -448,6 +456,10 @@ int dsa_register_switch(struct dsa_switch *ds)
 		return -EINVAL;
 	}
 
+	if (ds->ops->set_forwarding)
+		dev_add_param_bool(ds->dev, "forwarding", dsa_set_forwarding,
+				   NULL, &ds->forwarding_enable, ds);
+
 	ret = dsa_switch_parse_ports_of(ds, ds->dev->of_node);
 	if (ret)
 		return ret;
diff --git a/include/dsa.h b/include/dsa.h
index 527941c26949..ecf7c4f429f3 100644
--- a/include/dsa.h
+++ b/include/dsa.h
@@ -56,6 +56,9 @@ struct dsa_switch_ops {
 	int (*phy_read)(struct dsa_switch *ds, int port, int regnum);
 	int (*phy_write)(struct dsa_switch *ds, int port, int regnum, u16 val);
 	void (*adjust_link)(struct eth_device *dev);
+
+	/* enable/disable forwarding between all ports on the switch */
+	int (*set_forwarding)(struct dsa_switch *ds, bool enable);
 };
 
 struct dsa_port {
@@ -84,6 +87,7 @@ struct dsa_switch {
 	struct mii_bus *slave_mii_bus;
 	u32 phys_mii_mask;
 	void *priv;
+	u32 forwarding_enable;
 };
 
 static inline struct dsa_port *dsa_to_port(struct dsa_switch *ds, int p)
-- 
2.39.5

[PATCH v1 2/3] Documentation: networking: Add DSA switch support documentation

[Oleksij Rempel]

Add documentation for Distributed Switch Architecture (DSA) support in
Barebox. It introduces the `forwarding` parameter, which allows
configuring a DSA switch to operate in either isolated mode (default) or
forwarding mode.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 Documentation/user/networking.rst | 74 +++++++++++++++++++++++++++++++
 1 file changed, 74 insertions(+)

diff --git a/Documentation/user/networking.rst b/Documentation/user/networking.rst
index 2306cb6a60d1..71703f064bee 100644
--- a/Documentation/user/networking.rst
+++ b/Documentation/user/networking.rst
@@ -186,3 +186,77 @@ barebox:
 The netconsole can be used just like any other console. Note, however, that the
 simple console protocol is UDP based, so there is no guarantee about packet
 loss.
+
+DSA (Distributed Switch Architecture) Support in Barebox
+--------------------------------------------------------
+
+Barebox includes support for DSA (Distributed Switch Architecture), allowing
+for basic configuration and management of network switches within the
+bootloader.
+
+DSA enables network devices to use a switch framework where each port of the
+switch is treated as a separate network interface, while still allowing packet
+forwarding between ports when enabled.
+
+DSA Configuration
+^^^^^^^^^^^^^^^^^
+
+DSA switches are managed through device parameters, similar to network
+interfaces. Each switch is identified as a separate device, typically named
+``switch0`` or ``switch@00`` depending on the bus address.
+
+Global Forwarding Control
+"""""""""""""""""""""""""
+
+A parameter, ``forwarding``, allows configuring whether a switch operates
+in **isolated mode** (default) or **forwarding mode**:
+
+- **Isolated Mode** (default): Each port is treated as an independent interface,
+  with no forwarding between ports.
+
+- **Forwarding Mode**: The switch allows forwarding of packets between ports,
+  acting as a traditional non-managed switch.
+
+To check the current DSA switch settings, use:
+
+.. code-block:: sh
+
+  barebox:/ devinfo switch0
+  Parameters:
+    forwarding: 0 (type: bool)
+
+To enable forwarding mode:
+
+.. code-block:: sh
+
+  dev.switch0.forwarding=1
+
+To disable forwarding and revert to isolated mode:
+
+.. code-block:: sh
+
+  dev.switch0.forwarding=0
+
+Persisting Configuration
+""""""""""""""""""""""""
+
+To ensure that the forwarding mode setting persists across reboots,
+it can be stored as a nonvolatile (nv) variable:
+
+.. code-block:: sh
+
+  nv dev.switch0.forwarding=1
+
+This will configure the switch to always boot in forwarding mode.
+
+Integration with Network Interfaces
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Each port of the DSA switch is exposed as an independent network interface in
+Barebox. However, when forwarding is enabled, packets can be forwarded between
+these interfaces without requiring intervention from the CPU.
+
+To configure network settings for individual ports, use standard network
+configuration variables (e.g., ``eth0.ipaddr``, ``eth0.mode``, etc.). These
+settings are applied per port and are independent of the global switch
+forwarding configuration.
-- 
2.39.5

[PATCH v1 3/3] net: dsa: sja1105: Add support for global forwarding mode

[Oleksij Rempel]

Add support for global forwarding mode in the SJA1105 DSA driver,
allowing dynamic control over whether the switch forwards traffic
between all ports or restricts communication to only CPU-port
connections.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 drivers/net/sja1105.c | 77 +++++++++++++++++++++++++++++++++----------
 1 file changed, 59 insertions(+), 18 deletions(-)

diff --git a/drivers/net/sja1105.c b/drivers/net/sja1105.c
index 4ef30b8c81f1..aaf9237dc19d 100644
--- a/drivers/net/sja1105.c
+++ b/drivers/net/sja1105.c
@@ -1230,11 +1230,13 @@ static int sja1105_init_mii_settings(struct sja1105_private *priv)
 	return 0;
 }
 
-static void sja1105_setup_tagging(struct sja1105_private *priv, int port)
+static void sja1105_setup_tagging(struct sja1105_private *priv, int port,
+				  bool forward_all)
 {
 	struct sja1105_vlan_lookup_entry *vlan;
 	struct dsa_switch *ds = &priv->ds;
 	int cpu = ds->cpu_port;
+	u8 vlan_mask;
 
 	/* The CPU port is implicitly configured by
 	 * configuring the front-panel ports
@@ -1246,8 +1248,16 @@ static void sja1105_setup_tagging(struct sja1105_private *priv, int port)
 
 	priv->pvid[port] = DSA_8021Q_DIR_TX | DSA_8021Q_PORT(port);
 
-	vlan[port].vmemb_port	= BIT(port) | BIT(cpu);
-	vlan[port].vlan_bc	= BIT(port) | BIT(cpu);
+	if (forward_all) {
+		/* All ports in the same VLAN */
+		vlan_mask = (1 << ds->num_ports) - 1;
+	} else {
+		/* Only allow port ↔ CPU communication */
+		vlan_mask = BIT(port) | BIT(cpu);
+	}
+
+	vlan[port].vmemb_port	= vlan_mask;
+	vlan[port].vlan_bc	= vlan_mask;
 	vlan[port].tag_port	= BIT(cpu);
 	vlan[port].vlanid	= priv->pvid[port];
 	vlan[port].type_entry	= SJA1110_VLAN_D_TAG;
@@ -1269,7 +1279,7 @@ static int sja1105_init_vlan(struct sja1105_private *priv)
 	table->entry_count = ds->num_ports;
 
 	for (port = 0; port < ds->num_ports; port++)
-		sja1105_setup_tagging(priv, port);
+		sja1105_setup_tagging(priv, port, false);
 
 	return 0;
 }
@@ -1283,33 +1293,47 @@ sja1105_port_allow_traffic(struct sja1105_l2_forwarding_entry *l2_fwd,
 	l2_fwd[from].fl_domain  |= BIT(to);
 }
 
-static int sja1105_init_l2_forwarding(struct sja1105_private *priv)
+static int sja1105_init_l2_forwarding(struct sja1105_private *priv,
+				      bool forward_all)
 {
 	struct sja1105_l2_forwarding_entry *l2fwd;
 	struct dsa_switch *ds = &priv->ds;
 	struct sja1105_table *table;
 	int cpu = ds->cpu_port;
-	int i;
+	int i, j;
 
 	table = &priv->static_config.tables[BLK_IDX_L2_FORWARDING];
 
-	table->entries = calloc(SJA1105_MAX_L2_FORWARDING_COUNT,
-				table->ops->unpacked_entry_size);
-	if (!table->entries)
-		return -ENOMEM;
+	if (!table->entries) {
+		table->entries = calloc(SJA1105_MAX_L2_FORWARDING_COUNT,
+					table->ops->unpacked_entry_size);
+		if (!table->entries)
+			return -ENOMEM;
+	}
 
 	table->entry_count = SJA1105_MAX_L2_FORWARDING_COUNT;
 
 	l2fwd = table->entries;
 
-	/* First 5 entries define the forwarding rules */
-	for (i = 0; i < ds->num_ports; i++) {
-		if (i == cpu)
-			continue;
-
-		sja1105_port_allow_traffic(l2fwd, i, cpu);
-		sja1105_port_allow_traffic(l2fwd, cpu, i);
+	if (forward_all) {
+		/* Forwarding mode: All ports can talk to each other */
+		for (i = 0; i < ds->num_ports; i++) {
+			for (j = 0; j < ds->num_ports; j++) {
+				if (i == j)
+					continue;
+				sja1105_port_allow_traffic(l2fwd, i, j);
+			}
+		}
+	} else {
+		/* Default mode: Each port only forwards to/from the CPU */
+		for (i = 0; i < ds->num_ports; i++) {
+			if (i == cpu)
+				continue;
+			sja1105_port_allow_traffic(l2fwd, i, cpu);
+			sja1105_port_allow_traffic(l2fwd, cpu, i);
+		}
 	}
+
 	/* Next 8 entries define VLAN PCP mapping from ingress to egress.
 	 * Leave them unpopulated (implicitly 0) but present.
 	 */
@@ -1490,7 +1514,7 @@ static int sja1105_static_config_init(struct sja1105_private *priv)
 	rc = sja1105_init_mii_settings(priv);
 	if (rc < 0)
 		return rc;
-	rc = sja1105_init_l2_forwarding(priv);
+	rc = sja1105_init_l2_forwarding(priv, false);
 	if (rc < 0)
 		return rc;
 	rc = sja1105_init_l2_forwarding_params(priv);
@@ -2866,12 +2890,29 @@ static int sja1105_cpu_port_enable(struct dsa_port *dp, int port,
 	return sja1105_static_config_reload(priv);
 }
 
+static int sja1105_set_forwarding(struct dsa_switch *ds, bool enable)
+{
+	struct device *dev = ds->dev;
+	struct sja1105_private *priv = dev_get_priv(dev);
+	int port, ret;
+
+	for (port = 0; port < ds->num_ports; port++)
+		sja1105_setup_tagging(priv, port, enable);
+
+	ret = sja1105_init_l2_forwarding(priv, enable);
+	if (ret)
+		return ret;
+
+	return sja1105_static_config_reload(priv);
+}
+
 static const struct dsa_switch_ops sja1105_dsa_ops = {
 	.port_pre_enable	= sja1105_port_pre_enable,
 	.port_enable		= sja1105_cpu_port_enable,
 	.adjust_link		= sja1105_adjust_link,
 	.xmit			= sja1105_xmit,
 	.rcv			= sja1105_rcv,
+	.set_forwarding		= sja1105_set_forwarding,
 };
 
 static int sja1105_init(struct sja1105_private *priv)
-- 
2.39.5

Re: [PATCH v1 1/3] net: dsa: Add global forwarding mode support

[Sascha Hauer]

On Wed, 12 Mar 2025 12:20:55 +0100, Oleksij Rempel wrote:
> This patch introduces a global forwarding mode control for DSA switches
> in Barebox.  It adds a new `forwarding` parameter that allows enabling
> or disabling forwarding  between all ports on a DSA switch.
> 
> This enables users to configure global forwarding dynamically via:
> dev.switch0.forwarding=1  # Enable forwarding
> dev.switch0.forwarding=0  # Disable forwarding (isolated mode)
> 
> [...]

Applied, thanks!

[1/3] net: dsa: Add global forwarding mode support
      https://git.pengutronix.de/cgit/barebox/commit/?id=e49028e88017 (link may not be stable)
[2/3] Documentation: networking: Add DSA switch support documentation
      https://git.pengutronix.de/cgit/barebox/commit/?id=861b6fcd7943 (link may not be stable)
[3/3] net: dsa: sja1105: Add support for global forwarding mode
      https://git.pengutronix.de/cgit/barebox/commit/?id=816fb00dbf28 (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>