Re: [PATCH net-next v9 12/12] net: airoha: add phylink support

On Mon, Jul 20, 2026 at 05:35:48PM +0200, Lorenzo Bianconi wrote:

quoted

Add phylink support for each GDM port. For GDM1 add the internal interface
mode as the only supported mode. For GDM2/3/4 add the required
configuration of the PCS to make the external PHY or attached SFP cage
work.

These needs to be defined in the GDM port node using the pcs-handle
property.

Update and provide a .get/set_link_ksettings function that use phylink
for ethtool OPs now that we fully support phylink.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/net/ethernet/airoha/Kconfig       |   1 +
 drivers/net/ethernet/airoha/airoha_eth.c  | 194 +++++++++++++++++++++-
 drivers/net/ethernet/airoha/airoha_eth.h  |   7 +-
 drivers/net/ethernet/airoha/airoha_regs.h |  12 ++
 4 files changed, 207 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/airoha/Kconfig b/drivers/net/ethernet/airoha/Kconfig
index 1f6640a15fc9..789906516bf8 100644
--- a/drivers/net/ethernet/airoha/Kconfig
+++ b/drivers/net/ethernet/airoha/Kconfig

@@ -20,6 +20,7 @@ config NET_AIROHA
 	depends on NET_DSA || !NET_DSA
 	select NET_AIROHA_NPU
 	select PAGE_POOL
+	select PHYLINK
 	help
 	  This driver supports the gigabit ethernet MACs in the
 	  Airoha SoC family.

diff --git a/drivers/net/ethernet/airoha/airoha_eth.c b/drivers/net/ethernet/airoha/airoha_eth.c
index 59001fd4b6f7..ed1ac032f337 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.c
+++ b/drivers/net/ethernet/airoha/airoha_eth.c

@@ -8,6 +8,7 @@
 #include <linux/of_reserved_mem.h>
 #include <linux/platform_device.h>
 #include <linux/tcp.h>
+#include <linux/pcs/pcs.h>
 #include <linux/u64_stats_sync.h>
 #include <net/dst_metadata.h>
 #include <net/page_pool/helpers.h>

@@ -1837,7 +1838,7 @@ static void airoha_update_hw_stats(struct airoha_gdm_dev *dev)
 	struct airoha_gdm_port *port = dev->port;
 	int i;
 
-	spin_lock(&port->stats_lock);
+	spin_lock(&port->lock);

Hi Christian,

as pointed out in a previous email, I do not like the approach of reusing this
spin_lock for airoha_mac_link_up(). Can we use rtl_lock() (when necessary) as
pointed out before?

For context, quoting from the previous series, the suggestion is to use
rtnl_is_locked() and then lock accordingly but I didn't find other usage of
that in other driver (aside from core net) and I don't like the use of
is_locked. I can already see the BOT saying that in the timeframe of
is_locked and writing the register another interface goes up causing a
race.

Guess I will add a simple mutex for this case and the other.

quoted

 
 	for (i = 0; i < ARRAY_SIZE(port->devs); i++) {
 		if (port->devs[i])

@@ -1848,7 +1849,7 @@ static void airoha_update_hw_stats(struct airoha_gdm_dev *dev)
 	airoha_fe_set(dev->eth, REG_FE_GDM_MIB_CLEAR(port->id),
 		      FE_GDM_MIB_RX_CLEAR_MASK | FE_GDM_MIB_TX_CLEAR_MASK);
 
-	spin_unlock(&port->stats_lock);
+	spin_unlock(&port->lock);
 }
 
 static void airoha_dev_set_xmit_frame_size(struct net_device *netdev)

@@ -1870,6 +1871,14 @@ static int airoha_dev_open(struct net_device *netdev)
 	u32 pse_port = FE_PSE_PORT_PPE1;
 	int err;
 
+	err = phylink_of_phy_connect(dev->phylink, netdev->dev.of_node, 0);
+	if (err) {
+		netdev_err(netdev, "could not attach PHY: %d\n", err);
+		return err;
+	}
+
+	phylink_start(dev->phylink);
+
 	netif_tx_start_all_queues(netdev);
 	err = airoha_set_vip_for_gdm_port(dev, true);
 	if (err)

@@ -1909,6 +1918,10 @@ static int airoha_dev_stop(struct net_device *netdev)
 		airoha_set_gdm_port_fwd_cfg(qdma->eth,
 					    REG_GDM_FWD_CFG(port->id),
 					    FE_PSE_PORT_DROP);
+
+	phylink_stop(dev->phylink);
+	phylink_disconnect_phy(dev->phylink);
+
 	return 0;
 }
 

@@ -2389,6 +2402,24 @@ airoha_ethtool_get_rmon_stats(struct net_device *netdev,
 	} while (u64_stats_fetch_retry(&dev->stats.syncp, start));
 }
 
+static int
+airoha_ethtool_get_link_ksettings(struct net_device *netdev,
+				  struct ethtool_link_ksettings *cmd)
+{
+	struct airoha_gdm_dev *dev = netdev_priv(netdev);
+
+	return phylink_ethtool_ksettings_get(dev->phylink, cmd);
+}
+
+static int
+airoha_ethtool_set_link_ksettings(struct net_device *netdev,
+				  const struct ethtool_link_ksettings *cmd)
+{
+	struct airoha_gdm_dev *dev = netdev_priv(netdev);
+
+	return phylink_ethtool_ksettings_set(dev->phylink, cmd);
+}
+
 static int airoha_qdma_set_chan_tx_sched(struct net_device *netdev,
 					 int channel, enum tx_sched_mode mode,
 					 const u16 *weights, u8 n_weights)

@@ -3120,7 +3151,8 @@ static const struct ethtool_ops airoha_ethtool_ops = {
 	.get_drvinfo		= airoha_ethtool_get_drvinfo,
 	.get_eth_mac_stats      = airoha_ethtool_get_mac_stats,
 	.get_rmon_stats		= airoha_ethtool_get_rmon_stats,
-	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
+	.get_link_ksettings	= airoha_ethtool_get_link_ksettings,
+	.set_link_ksettings	= airoha_ethtool_set_link_ksettings,
 	.get_link		= ethtool_op_get_link,
 };
 

@@ -3176,6 +3208,155 @@ bool airoha_is_valid_gdm_dev(struct airoha_eth *eth,
 	return false;
 }
 
+/* Nothing to do in MAC, everything is handled in PCS */
+static void airoha_mac_config(struct phylink_config *config, unsigned int mode,
+			      const struct phylink_link_state *state)
+{
+}
+
+static void airoha_mac_link_up(struct phylink_config *config, struct phy_device *phy,
+			       unsigned int mode, phy_interface_t interface,
+			       int speed, int duplex, bool tx_pause, bool rx_pause)
+{
+	struct airoha_gdm_dev *dev = container_of(config, struct airoha_gdm_dev,
+						  phylink_config);
+	struct airoha_gdm_port *port = dev->port;
+	struct airoha_eth *eth = dev->eth;
+	u32 frag_size_tx, frag_size_rx;
+	u32 mask, val;
+
+	/* TX/RX frag is configured only for GDM4 */
+	if (port->id != AIROHA_GDM4_IDX)
+		return;
+
+	switch (speed) {
+	case SPEED_10000:
+	case SPEED_5000:
+		frag_size_tx = 8;
+		frag_size_rx = 8;
+		break;
+	case SPEED_2500:
+		frag_size_tx = 2;
+		frag_size_rx = 1;
+		break;
+	default:
+		frag_size_tx = 1;
+		frag_size_rx = 0;
+	}
+
+	spin_lock(&port->lock);
+
+	/* Configure TX/RX frag based on speed */
+	if (dev->nbq == 1) {
+		mask = GDM4_SGMII1_TX_FRAG_SIZE_MASK;
+		val = FIELD_PREP(GDM4_SGMII1_TX_FRAG_SIZE_MASK,
+				 frag_size_tx);
+	}  else {
+		mask = GDM4_SGMII0_TX_FRAG_SIZE_MASK;
+		val = FIELD_PREP(GDM4_SGMII0_TX_FRAG_SIZE_MASK,
+				 frag_size_tx);
+	}
+	airoha_fe_rmw(eth, REG_FE_GDM4_TMBI_FRAG, mask, val);
+
+	if (dev->nbq == 1) {
+		mask = GDM4_SGMII1_RX_FRAG_SIZE_MASK;
+		val = FIELD_PREP(GDM4_SGMII1_RX_FRAG_SIZE_MASK,
+				 frag_size_rx);
+	} else {
+		mask = GDM4_SGMII0_RX_FRAG_SIZE_MASK;
+		val = FIELD_PREP(GDM4_SGMII0_RX_FRAG_SIZE_MASK,
+				 frag_size_rx);
+	}
+	airoha_fe_rmw(eth, REG_FE_GDM4_RMBI_FRAG, mask, val);
+
+	spin_unlock(&port->lock);
+}
+
+/* Nothing to do in MAC, everything is handled in PCS */
+static void airoha_mac_link_down(struct phylink_config *config, unsigned int mode,
+				 phy_interface_t interface)
+{
+}
+
+static const struct phylink_mac_ops airoha_phylink_ops = {
+	.mac_config = airoha_mac_config,
+	.mac_link_up = airoha_mac_link_up,
+	.mac_link_down = airoha_mac_link_down,
+};
+
+static int airoha_fill_available_pcs(struct phylink_config *config,
+				     struct phylink_pcs **available_pcs,
+				     unsigned int num_possible_pcs)
+{
+	struct device *dev = config->dev;
+
+	return fwnode_phylink_pcs_parse(dev_fwnode(dev), available_pcs,
+					num_possible_pcs);
+}
+
+static int airoha_setup_phylink(struct net_device *netdev)
+{
+	struct airoha_gdm_dev *dev = netdev_priv(netdev);
+	struct device_node *np = netdev->dev.of_node;
+	struct airoha_gdm_port *port = dev->port;
+	struct phylink_config *config;
+	phy_interface_t phy_mode;
+	struct phylink *phylink;
+	int err;
+
+	err = of_get_phy_mode(np, &phy_mode);
+	if (err) {
+		dev_err(&netdev->dev, "incorrect phy-mode\n");
+		return err;
+	}
+
+	config = &dev->phylink_config;
+	config->dev = &netdev->dev;
+	config->type = PHYLINK_NETDEV;
+
+	/*
+	 * GDM1 only supports internal for Embedded Switch
+	 * and doesn't require a PCS.
+	 */
+	if (port->id == AIROHA_GDM1_IDX) {
+		config->mac_capabilities = MAC_ASYM_PAUSE | MAC_SYM_PAUSE |
+					   MAC_10000FD;
+
+		__set_bit(PHY_INTERFACE_MODE_INTERNAL,
+			  config->supported_interfaces);
+	} else {
+		config->mac_capabilities = MAC_ASYM_PAUSE | MAC_SYM_PAUSE |
+					   MAC_10 | MAC_100 | MAC_1000 |
+					   MAC_2500FD | MAC_5000FD | MAC_10000FD;
+
+		config->num_possible_pcs = fwnode_phylink_pcs_count(dev_fwnode(config->dev));
+		config->fill_available_pcs = airoha_fill_available_pcs;
+
+		__set_bit(PHY_INTERFACE_MODE_SGMII,
+			  config->supported_interfaces);
+		__set_bit(PHY_INTERFACE_MODE_1000BASEX,
+			  config->supported_interfaces);
+		__set_bit(PHY_INTERFACE_MODE_2500BASEX,
+			  config->supported_interfaces);
+		__set_bit(PHY_INTERFACE_MODE_10GBASER,
+			  config->supported_interfaces);
+		__set_bit(PHY_INTERFACE_MODE_USXGMII,
+			  config->supported_interfaces);
+
+		phy_interface_copy(config->pcs_interfaces,
+				   config->supported_interfaces);
+	}
+
+	phylink = phylink_create(config, of_fwnode_handle(np),
+				 phy_mode, &airoha_phylink_ops);
+	if (IS_ERR(phylink))
+		return PTR_ERR(phylink);
+
+	dev->phylink = phylink;
+
+	return 0;
+}
+
 static int airoha_alloc_gdm_device(struct airoha_eth *eth,
 				   struct airoha_gdm_port *port,
 				   int nbq, struct device_node *np)

@@ -3239,7 +3420,7 @@ static int airoha_alloc_gdm_device(struct airoha_eth *eth,
 	dev->nbq = nbq;
 	port->devs[index] = dev;
 
-	return 0;
+	return airoha_setup_phylink(netdev);
 }
 
 static int airoha_alloc_gdm_port(struct airoha_eth *eth,

@@ -3274,7 +3455,7 @@ static int airoha_alloc_gdm_port(struct airoha_eth *eth,
 		return -ENOMEM;
 
 	port->id = id;
-	spin_lock_init(&port->stats_lock);
+	spin_lock_init(&port->lock);
 	eth->ports[p] = port;
 
 	err = airoha_metadata_dst_alloc(port);

@@ -3471,6 +3652,8 @@ static int airoha_probe(struct platform_device *pdev)
 			netdev = netdev_from_priv(dev);
 			if (netdev->reg_state == NETREG_REGISTERED)
 				unregister_netdev(netdev);
+			if (dev->phylink)
+				phylink_destroy(dev->phylink);
 			of_node_put(netdev->dev.of_node);
 		}
 		airoha_metadata_dst_free(port);

@@ -3509,6 +3692,7 @@ static void airoha_remove(struct platform_device *pdev)
 
 			netdev = netdev_from_priv(dev);
 			unregister_netdev(netdev);
+			phylink_destroy(dev->phylink);
 			of_node_put(netdev->dev.of_node);
 		}
 		airoha_metadata_dst_free(port);

diff --git a/drivers/net/ethernet/airoha/airoha_eth.h b/drivers/net/ethernet/airoha/airoha_eth.h
index f6d01a8e8da1..b49fc5304b3a 100644
--- a/drivers/net/ethernet/airoha/airoha_eth.h
+++ b/drivers/net/ethernet/airoha/airoha_eth.h

@@ -561,6 +561,9 @@ struct airoha_gdm_dev {
 	int nbq;
 
 	struct airoha_hw_stats stats;
+
+	struct phylink *phylink;
+	struct phylink_config phylink_config;
 };
 
 struct airoha_gdm_port {

@@ -568,8 +571,8 @@ struct airoha_gdm_port {
 	int id;
 	int users;
 
-	/* protect concurrent hw_stats accesses */
-	spinlock_t stats_lock;
+	/* protect concurrent hw_stats and frag register accesses */
+	spinlock_t lock;
 
 	struct metadata_dst *dsa_meta[AIROHA_MAX_DSA_PORTS];
 };

diff --git a/drivers/net/ethernet/airoha/airoha_regs.h b/drivers/net/ethernet/airoha/airoha_regs.h
index 6fed63d013b4..8df02f51211c 100644
--- a/drivers/net/ethernet/airoha/airoha_regs.h
+++ b/drivers/net/ethernet/airoha/airoha_regs.h

@@ -357,6 +357,18 @@
 #define IP_FRAGMENT_PORT_MASK		GENMASK(8, 5)
 #define IP_FRAGMENT_NBQ_MASK		GENMASK(4, 0)
 
+#define REG_FE_GDM4_TMBI_FRAG		0x2028
+#define GDM4_SGMII1_TX_WEIGHT_MASK	GENMASK(31, 26)
+#define GDM4_SGMII1_TX_FRAG_SIZE_MASK	GENMASK(25, 16)
+#define GDM4_SGMII0_TX_WEIGHT_MASK	GENMASK(15, 10)
+#define GDM4_SGMII0_TX_FRAG_SIZE_MASK	GENMASK(9, 0)
+
+#define REG_FE_GDM4_RMBI_FRAG		0x202c
+#define GDM4_SGMII1_RX_WEIGHT_MASK	GENMASK(31, 26)
+#define GDM4_SGMII1_RX_FRAG_SIZE_MASK	GENMASK(25, 16)
+#define GDM4_SGMII0_RX_WEIGHT_MASK	GENMASK(15, 10)
+#define GDM4_SGMII0_RX_FRAG_SIZE_MASK	GENMASK(9, 0)
+
 #define REG_MC_VLAN_EN			0x2100
 #define MC_VLAN_EN_MASK			BIT(0)
 

-- 
2.53.0

-- 
	Ansuel