[PATCH net-next v3] net: stmmac: dwmac-qcom-ethqos: Add support for 2.5G SGMII

[Sneh Shah]

Serdes phy needs to operate at 2500 mode for 2.5G speed and 1000
mode for 1G/100M/10M speed.
Added changes to configure serdes phy and mac based on link speed.
Changing serdes phy speed involves multiple register writes for
serdes block. To avoid redundant write opertions only update serdes
phy when new speed is different.

Signed-off-by: Sneh Shah <quic_snehshah at quicinc.com>
---
v3 changelog:
- updated commit message
---
v2 changelog:
- updated stmmac_pcs_ane to support autoneg disable
- Update serdes speed to 1000 for 100M and 10M also
---
 .../stmicro/stmmac/dwmac-qcom-ethqos.c        | 27 +++++++++++++++++++
 .../net/ethernet/stmicro/stmmac/stmmac_pcs.h  |  2 ++
 2 files changed, 29 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
index d3bf42d0fceb..c236c939fbe9 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-qcom-ethqos.c
@@ -103,6 +103,7 @@ struct qcom_ethqos {
 	struct clk *link_clk;
 	struct phy *serdes_phy;
 	unsigned int speed;
+	int serdes_speed;
 	phy_interface_t phy_mode;
 
 	const struct ethqos_emac_por *por;
@@ -602,21 +603,46 @@ static int ethqos_configure_sgmii(struct qcom_ethqos *ethqos)
 {
 	int val;
 
+	struct platform_device *pdev = ethqos->pdev;
+	struct net_device *dev = platform_get_drvdata(pdev);
+	struct stmmac_priv *priv = netdev_priv(dev);
 	val = readl(ethqos->mac_base + MAC_CTRL_REG);
 
 	switch (ethqos->speed) {
+	case SPEED_2500:
+		val &= ~ETHQOS_MAC_CTRL_PORT_SEL;
+		rgmii_updatel(ethqos, RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
+			      RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
+			      RGMII_IO_MACRO_CONFIG2);
+		if (ethqos->serdes_speed != SPEED_2500)
+			phy_set_speed(ethqos->serdes_phy, SPEED_2500);
+		ethqos->serdes_speed = SPEED_2500;
+		stmmac_pcs_ctrl_ane(priv, priv->ioaddr, 0, 0, 0);
+		break;
 	case SPEED_1000:
 		val &= ~ETHQOS_MAC_CTRL_PORT_SEL;
 		rgmii_updatel(ethqos, RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
 			      RGMII_CONFIG2_RGMII_CLK_SEL_CFG,
 			      RGMII_IO_MACRO_CONFIG2);
+		if (ethqos->serdes_speed != SPEED_1000)
+			phy_set_speed(ethqos->serdes_phy, SPEED_1000);
+		ethqos->serdes_speed = SPEED_1000;
+		stmmac_pcs_ctrl_ane(priv, priv->ioaddr, 1, 0, 0);
 		break;
 	case SPEED_100:
 		val |= ETHQOS_MAC_CTRL_PORT_SEL | ETHQOS_MAC_CTRL_SPEED_MODE;
+		if (ethqos->serdes_speed != SPEED_1000)
+			phy_set_speed(ethqos->serdes_phy, SPEED_1000);
+		ethqos->serdes_speed = SPEED_1000;
+		stmmac_pcs_ctrl_ane(priv, priv->ioaddr, 1, 0, 0);
 		break;
 	case SPEED_10:
 		val |= ETHQOS_MAC_CTRL_PORT_SEL;
 		val &= ~ETHQOS_MAC_CTRL_SPEED_MODE;
+		if (ethqos->serdes_speed != SPEED_1000)
+			phy_set_speed(ethqos->serdes_phy, ethqos->speed);
+		ethqos->serdes_speed = SPEED_1000;
+		stmmac_pcs_ctrl_ane(priv, priv->ioaddr, 1, 0, 0);
 		break;
 	}
 
@@ -789,6 +815,7 @@ static int qcom_ethqos_probe(struct platform_device *pdev)
 				     "Failed to get serdes phy\n");
 
 	ethqos->speed = SPEED_1000;
+	ethqos->serdes_speed = SPEED_1000;
 	ethqos_update_link_clk(ethqos, SPEED_1000);
 	ethqos_set_func_clk_en(ethqos);
 
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
index aefc121464b5..13a30e6df4c1 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_pcs.h
@@ -110,6 +110,8 @@ static inline void dwmac_ctrl_ane(void __iomem *ioaddr, u32 reg, bool ane,
 	/* Enable and restart the Auto-Negotiation */
 	if (ane)
 		value |= GMAC_AN_CTRL_ANE | GMAC_AN_CTRL_RAN;
+	else
+		value &= ~GMAC_AN_CTRL_ANE;
 
 	/* In case of MAC-2-MAC connection, block is configured to operate
 	 * according to MAC conf register.
-- 
2.17.1