From bdcad9ab6b0f071e8492d88064a58323d7155aa7 Mon Sep 17 00:00:00 2001
From: Christian Marangi <ansuelsmth@gmail.com>
Date: Fri, 17 Jan 2025 13:23:13 +0100
Subject: [PATCH] net: airoha: add phylink support for GDM2/4

Add phylink support for GDM2/4 port that require configuration of the
PCS to make the external PHY or attached SFP cage work.

Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>
---
 drivers/net/ethernet/airoha/airoha_eth.c  | 133 ++++++++++++++++++++++
 drivers/net/ethernet/airoha/airoha_eth.h  |   4 +
 drivers/net/ethernet/airoha/airoha_regs.h |  12 ++
 3 files changed, 149 insertions(+)

--- 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-airoha.h>
 #include <linux/u64_stats_sync.h>
 #include <net/dst_metadata.h>
 #include <net/page_pool/helpers.h>
@@ -71,6 +72,11 @@ static void airoha_qdma_irq_disable(stru
 	airoha_qdma_set_irqmask(irq_bank, index, mask, 0);
 }
 
+static bool airhoa_is_phy_external(struct airoha_gdm_port *port)
+{
+	return port->id != 1;
+}
+
 static void airoha_set_macaddr(struct airoha_gdm_port *port, const u8 *addr)
 {
 	struct airoha_eth *eth = port->qdma->eth;
@@ -1621,6 +1627,17 @@ static int airoha_dev_open(struct net_de
 	struct airoha_gdm_port *port = netdev_priv(dev);
 	struct airoha_qdma *qdma = port->qdma;
 
+	if (airhoa_is_phy_external(port)) {
+		err = phylink_of_phy_connect(port->phylink, dev->dev.of_node, 0);
+		if (err) {
+			netdev_err(dev, "%s: could not attach PHY: %d\n", __func__,
+				   err);
+			return err;
+		}
+
+		phylink_start(port->phylink);
+	}
+
 	netif_tx_start_all_queues(dev);
 	err = airoha_set_vip_for_gdm_port(port, true);
 	if (err)
@@ -1674,6 +1691,11 @@ static int airoha_dev_stop(struct net_de
 		}
 	}
 
+	if (airhoa_is_phy_external(port)) {
+		phylink_stop(port->phylink);
+		phylink_disconnect_phy(port->phylink);
+	}
+
 	return 0;
 }
 
@@ -2816,6 +2838,20 @@ static const struct ethtool_ops airoha_e
 	.get_link		= ethtool_op_get_link,
 };
 
+static struct phylink_pcs *airoha_phylink_mac_select_pcs(struct phylink_config *config,
+							 phy_interface_t interface)
+{
+	struct airoha_gdm_port *port = container_of(config, struct airoha_gdm_port,
+						    phylink_config);
+
+	return port->pcs;
+}
+
+static void airoha_mac_config(struct phylink_config *config, unsigned int mode,
+			      const struct phylink_link_state *state)
+{
+}
+
 static int airoha_metadata_dst_alloc(struct airoha_gdm_port *port)
 {
 	int i;
@@ -2860,6 +2896,99 @@ bool airoha_is_valid_gdm_port(struct air
 	return false;
 }
 
+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_port *port = container_of(config, struct airoha_gdm_port,
+						    phylink_config);
+	struct airoha_qdma *qdma = port->qdma;
+	struct airoha_eth *eth = qdma->eth;
+	u32 frag_size_tx, frag_size_rx;
+
+	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;
+	}
+
+	/* Configure TX/RX frag based on speed */
+	if (port->id == 4) {
+		airoha_fe_rmw(eth, REG_GDMA4_TMBI_FRAG, GDMA4_SGMII0_TX_FRAG_SIZE,
+			      FIELD_PREP(GDMA4_SGMII0_TX_FRAG_SIZE, frag_size_tx));
+
+		airoha_fe_rmw(eth, REG_GDMA4_RMBI_FRAG, GDMA4_SGMII0_RX_FRAG_SIZE,
+			      FIELD_PREP(GDMA4_SGMII0_RX_FRAG_SIZE, frag_size_rx));
+	}
+}
+
+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_select_pcs = airoha_phylink_mac_select_pcs,
+	.mac_config = airoha_mac_config,
+	.mac_link_up = airoha_mac_link_up,
+	.mac_link_down = airoha_mac_link_down,
+};
+
+static int airoha_setup_phylink(struct net_device *dev)
+{
+	struct airoha_gdm_port *port = netdev_priv(dev);
+	struct device_node *np = dev->dev.of_node;
+	phy_interface_t phy_mode;
+	struct phylink *phylink;
+	int err;
+
+	err = of_get_phy_mode(np, &phy_mode);
+	if (err) {
+		dev_err(&dev->dev, "incorrect phy-mode\n");
+		return err;
+	}
+
+	port->phylink_config.dev = &dev->dev;
+	port->phylink_config.type = PHYLINK_NETDEV;
+	port->phylink_config.mac_capabilities = MAC_ASYM_PAUSE | MAC_SYM_PAUSE |
+						MAC_10 | MAC_100 | MAC_1000 | MAC_2500FD |
+						MAC_5000FD | MAC_10000FD;
+
+	__set_bit(PHY_INTERFACE_MODE_SGMII,
+		  port->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_1000BASEX,
+		  port->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_2500BASEX,
+		  port->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_USXGMII,
+		  port->phylink_config.supported_interfaces);
+	__set_bit(PHY_INTERFACE_MODE_10GBASER,
+		  port->phylink_config.supported_interfaces);
+
+	port->pcs = airoha_pcs_create(&dev->dev);
+	if (IS_ERR(port->pcs))
+		return PTR_ERR(port->pcs);
+
+	phylink = phylink_create(&port->phylink_config,
+				 of_fwnode_handle(np),
+				 phy_mode, &airoha_phylink_ops);
+	if (IS_ERR(phylink))
+		return PTR_ERR(phylink);
+
+	port->phylink = phylink;
+
+	return 0;
+}
+
 static int airoha_alloc_gdm_port(struct airoha_eth *eth,
 				 struct device_node *np, int index)
 {
@@ -2938,6 +3067,12 @@ static int airoha_alloc_gdm_port(struct
 	if (err)
 		return err;
 
+	if (airhoa_is_phy_external(port)) {
+		err = airoha_setup_phylink(dev);
+		if (err)
+			goto free_metadata_dst;
+	}
+
 	err = register_netdev(dev);
 	if (err)
 		goto free_metadata_dst;
@@ -3053,6 +3188,10 @@ error_hw_cleanup:
 		if (port && port->dev->reg_state == NETREG_REGISTERED) {
 			unregister_netdev(port->dev);
 			airoha_metadata_dst_free(port);
+			if (airhoa_is_phy_external(port)) {
+				phylink_destroy(port->phylink);
+				airoha_pcs_destroy(port->pcs);
+			}
 		}
 	}
 	free_netdev(eth->napi_dev);
@@ -3080,6 +3219,10 @@ static void airoha_remove(struct platfor
 		airoha_dev_stop(port->dev);
 		unregister_netdev(port->dev);
 		airoha_metadata_dst_free(port);
+		if (airhoa_is_phy_external(port)) {
+			phylink_destroy(port->phylink);
+			airoha_pcs_destroy(port->pcs);
+		}
 	}
 	free_netdev(eth->napi_dev);
 
--- a/drivers/net/ethernet/airoha/airoha_eth.h
+++ b/drivers/net/ethernet/airoha/airoha_eth.h
@@ -536,6 +536,10 @@ struct airoha_gdm_port {
 	struct net_device *dev;
 	int id;
 
+	struct phylink *phylink;
+	struct phylink_config phylink_config;
+	struct phylink_pcs *pcs;
+
 	struct airoha_hw_stats stats;
 
 	DECLARE_BITMAP(qos_sq_bmap, AIROHA_NUM_QOS_CHANNELS);
--- a/drivers/net/ethernet/airoha/airoha_regs.h
+++ b/drivers/net/ethernet/airoha/airoha_regs.h
@@ -359,6 +359,18 @@
 #define IP_FRAGMENT_PORT_MASK		GENMASK(8, 5)
 #define IP_FRAGMENT_NBQ_MASK		GENMASK(4, 0)
 
+#define REG_GDMA4_TMBI_FRAG		0x2028
+#define GDMA4_SGMII1_TX_WEIGHT		GENMASK(31, 26)
+#define GDMA4_SGMII1_TX_FRAG_SIZE	GENMASK(25, 16)
+#define GDMA4_SGMII0_TX_WEIGHT		GENMASK(15, 10)
+#define GDMA4_SGMII0_TX_FRAG_SIZE	GENMASK(9, 0)
+
+#define REG_GDMA4_RMBI_FRAG		0x202c
+#define GDMA4_SGMII1_RX_WEIGHT		GENMASK(31, 26)
+#define GDMA4_SGMII1_RX_FRAG_SIZE	GENMASK(25, 16)
+#define GDMA4_SGMII0_RX_WEIGHT		GENMASK(15, 10)
+#define GDMA4_SGMII0_RX_FRAG_SIZE	GENMASK(9, 0)
+
 #define REG_MC_VLAN_EN			0x2100
 #define MC_VLAN_EN_MASK			BIT(0)
 
