[PATCH net-next v3 4/4] net: dp83869: Add RGMII internal delay configuration

[Dan Murphy <dmurphy@xxxxxx>]

Add RGMII internal delay configuration for Rx and Tx.

Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
---
 drivers/net/phy/dp83869.c | 91 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 88 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c
index cfb22a21a2e6..1c440e0c0d64 100644
--- a/drivers/net/phy/dp83869.c
+++ b/drivers/net/phy/dp83869.c
@@ -64,6 +64,9 @@
 #define DP83869_RGMII_TX_CLK_DELAY_EN		BIT(1)
 #define DP83869_RGMII_RX_CLK_DELAY_EN		BIT(0)
 
+/* RGMIIDCTL */
+#define DP83869_RGMII_CLK_DELAY_SHIFT		4
+
 /* STRAP_STS1 bits */
 #define DP83869_STRAP_OP_MODE_MASK		GENMASK(2, 0)
 #define DP83869_STRAP_STS1_RESERVED		BIT(11)
@@ -78,9 +81,6 @@
 #define DP83869_PHYCR_FIFO_DEPTH_MASK	GENMASK(15, 12)
 #define DP83869_PHYCR_RESERVED_MASK	BIT(11)
 
-/* RGMIIDCTL bits */
-#define DP83869_RGMII_TX_CLK_DELAY_SHIFT	4
-
 /* IO_MUX_CFG bits */
 #define DP83869_IO_MUX_CFG_IO_IMPEDANCE_CTRL	0x1f
 
@@ -99,6 +99,10 @@
 #define DP83869_OP_MODE_MII			BIT(5)
 #define DP83869_SGMII_RGMII_BRIDGE		BIT(6)
 
+static int dp83869_internal_delay[] = {250, 500, 750, 1000, 1250, 1500, 1750,
+				       2000, 2250, 2500, 2750, 3000, 3250,
+				       3500, 3750, 4000};
+
 enum {
 	DP83869_PORT_MIRRORING_KEEP,
 	DP83869_PORT_MIRRORING_EN,
@@ -108,6 +112,8 @@ enum {
 struct dp83869_private {
 	int tx_fifo_depth;
 	int rx_fifo_depth;
+	s32 rx_id_delay;
+	s32 tx_id_delay;
 	int io_impedance;
 	int port_mirroring;
 	bool rxctrl_strap_quirk;
@@ -218,6 +224,7 @@ static int dp83869_of_init(struct phy_device *phydev)
 		ret = phy_read_mmd(phydev, DP83869_DEVADDR, DP83869_STRAP_STS1);
 		if (ret < 0)
 			return ret;
+
 		if (ret & DP83869_STRAP_MIRROR_ENABLED)
 			dp83869->port_mirroring = DP83869_PORT_MIRRORING_EN;
 		else
@@ -232,6 +239,20 @@ static int dp83869_of_init(struct phy_device *phydev)
 				 &dp83869->tx_fifo_depth))
 		dp83869->tx_fifo_depth = DP83869_PHYCR_FIFO_DEPTH_4_B_NIB;
 
+	ret = of_property_read_u32(of_node, "rx-internal-delay-ps",
+				   &dp83869->rx_id_delay);
+	if (ret) {
+		dp83869->rx_id_delay = ret;
+		ret = 0;
+	}
+
+	ret = of_property_read_u32(of_node, "tx-internal-delay-ps",
+				   &dp83869->tx_id_delay);
+	if (ret) {
+		dp83869->tx_id_delay = ret;
+		ret = 0;
+	}
+
 	return ret;
 }
 #else
@@ -367,10 +388,45 @@ static int dp83869_configure_mode(struct phy_device *phydev,
 	return ret;
 }
 
+static int dp83869_get_delay(struct phy_device *phydev)
+{
+	struct dp83869_private *dp83869 = phydev->priv;
+	int delay_size = ARRAY_SIZE(dp83869_internal_delay);
+	int tx_delay = 0;
+	int rx_delay = 0;
+
+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) {
+		tx_delay = phy_get_delay_index(phydev,
+					       &dp83869_internal_delay[0],
+					       delay_size, dp83869->tx_id_delay,
+					       false);
+		if (tx_delay < 0) {
+			phydev_err(phydev, "Tx internal delay is invalid\n");
+			return tx_delay;
+		}
+	}
+
+	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID ||
+	    phydev->interface == PHY_INTERFACE_MODE_RGMII_ID) {
+		rx_delay = phy_get_delay_index(phydev,
+					       &dp83869_internal_delay[0],
+					       delay_size, dp83869->rx_id_delay,
+					       false);
+		if (rx_delay < 0) {
+			phydev_err(phydev, "Rx internal delay is invalid\n");
+			return rx_delay;
+		}
+	}
+
+	return rx_delay | tx_delay << DP83869_RGMII_CLK_DELAY_SHIFT;
+}
+
 static int dp83869_config_init(struct phy_device *phydev)
 {
 	struct dp83869_private *dp83869 = phydev->priv;
 	int ret, val;
+	int delay;
 
 	ret = dp83869_configure_mode(phydev, dp83869);
 	if (ret)
@@ -394,6 +450,35 @@ static int dp83869_config_init(struct phy_device *phydev)
 				     dp83869->clk_output_sel <<
 				     DP83869_IO_MUX_CFG_CLK_O_SEL_SHIFT);
 
+	if (phy_interface_is_rgmii(phydev)) {
+		ret = dp83869_get_delay(phydev);
+		if (ret < 0)
+			return ret;
+
+		delay = ret;
+		ret = phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIIDCTL,
+				    delay);
+		if (ret)
+			return ret;
+
+		val = phy_read_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIICTL);
+		val &= ~(DP83869_RGMII_TX_CLK_DELAY_EN |
+			 DP83869_RGMII_RX_CLK_DELAY_EN);
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID)
+			val |= (DP83869_RGMII_TX_CLK_DELAY_EN |
+				DP83869_RGMII_RX_CLK_DELAY_EN);
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID)
+			val |= DP83869_RGMII_TX_CLK_DELAY_EN;
+
+		if (phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID)
+			val |= DP83869_RGMII_RX_CLK_DELAY_EN;
+
+		ret = phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIICTL,
+				    val);
+	}
+
 	return ret;
 }
 
-- 
2.26.2