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

From: Dan Murphy
Date: Thu May 21 2020 - 13:48:50 EST


Add RGMII internal delay configuration for Rx and Tx.

Signed-off-by: Dan Murphy <dmurphy@xxxxxx>
---
drivers/net/phy/dp83869.c | 101 ++++++++++++++++++++++++++++++++++++++
1 file changed, 101 insertions(+)

diff --git a/drivers/net/phy/dp83869.c b/drivers/net/phy/dp83869.c
index cfb22a21a2e6..40c34fefffe4 100644
--- a/drivers/net/phy/dp83869.c
+++ b/drivers/net/phy/dp83869.c
@@ -99,6 +99,14 @@
#define DP83869_OP_MODE_MII BIT(5)
#define DP83869_SGMII_RGMII_BRIDGE BIT(6)

+/* RGMIIDCTL bits */
+#define DP83869_RGMII_TX_CLK_DELAY_SHIFT 4
+#define DP83869_RGMII_CLK_DELAY_INV 0
+
+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 +116,8 @@ enum {
struct dp83869_private {
int tx_fifo_depth;
int rx_fifo_depth;
+ u32 rx_id_delay;
+ u32 tx_id_delay;
int io_impedance;
int port_mirroring;
bool rxctrl_strap_quirk;
@@ -182,6 +192,7 @@ static int dp83869_of_init(struct phy_device *phydev)
struct dp83869_private *dp83869 = phydev->priv;
struct device *dev = &phydev->mdio.dev;
struct device_node *of_node = dev->of_node;
+ int delay_size = ARRAY_SIZE(dp83869_internal_delay);
int ret;

if (!of_node)
@@ -232,6 +243,26 @@ static int dp83869_of_init(struct phy_device *phydev)
&dp83869->tx_fifo_depth))
dp83869->tx_fifo_depth = DP83869_PHYCR_FIFO_DEPTH_4_B_NIB;

+ dp83869->rx_id_delay = DP83869_RGMII_CLK_DELAY_INV;
+ ret = of_property_read_u32(of_node, "rx-internal-delay",
+ &dp83869->rx_id_delay);
+ if (!ret && dp83869->rx_id_delay > dp83869_internal_delay[delay_size]) {
+ phydev_err(phydev,
+ "rx-internal-delay value of %u out of range\n",
+ dp83869->rx_id_delay);
+ return -EINVAL;
+ }
+
+ dp83869->tx_id_delay = DP83869_RGMII_CLK_DELAY_INV;
+ ret = of_property_read_u32(of_node, "tx-internal-delay",
+ &dp83869->tx_id_delay);
+ if (!ret && dp83869->tx_id_delay > dp83869_internal_delay[delay_size]) {
+ phydev_err(phydev,
+ "tx-internal-delay value of %u out of range\n",
+ dp83869->tx_id_delay);
+ return -EINVAL;
+ }
+
return ret;
}
#else
@@ -270,6 +301,29 @@ static int dp83869_configure_rgmii(struct phy_device *phydev,
return ret;
}

+static int dp83869_verify_rgmii_cfg(struct phy_device *phydev)
+{
+ struct dp83869_private *dp83869 = phydev->priv;
+
+ /* RX delay *must* be specified if internal delay of RX is used. */
+ if ((phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+ phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) &&
+ dp83869->rx_id_delay == DP83869_RGMII_CLK_DELAY_INV) {
+ phydev_err(phydev, "ti,rx-internal-delay must be specified\n");
+ return -EINVAL;
+ }
+
+ /* TX delay *must* be specified if internal delay of TX is used. */
+ if ((phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
+ phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) &&
+ dp83869->tx_id_delay == DP83869_RGMII_CLK_DELAY_INV) {
+ phydev_err(phydev, "ti,tx-internal-delay must be specified\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static int dp83869_configure_mode(struct phy_device *phydev,
struct dp83869_private *dp83869)
{
@@ -371,6 +425,12 @@ static int dp83869_config_init(struct phy_device *phydev)
{
struct dp83869_private *dp83869 = phydev->priv;
int ret, val;
+ int delay_size = ARRAY_SIZE(dp83869_internal_delay);
+ int delay = 0;
+
+ ret = dp83869_verify_rgmii_cfg(phydev);
+ if (ret)
+ return ret;

ret = dp83869_configure_mode(phydev, dp83869);
if (ret)
@@ -394,6 +454,47 @@ 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)) {
+ 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;
+
+ phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIICTL, val);
+
+ if (dp83869->rx_id_delay) {
+ val = phy_get_delay_index(phydev,
+ &dp83869_internal_delay[0],
+ delay_size,
+ dp83869->rx_id_delay);
+ if (val < 0)
+ return val;
+
+ delay |= val;
+ }
+
+ if (dp83869->tx_id_delay) {
+ val = phy_get_delay_index(phydev,
+ &dp83869_internal_delay[0],
+ delay_size,
+ dp83869->tx_id_delay);
+ if (val < 0)
+ return val;
+
+ delay |= val << DP83869_RGMII_TX_CLK_DELAY_SHIFT;
+ }
+
+ phy_write_mmd(phydev, DP83869_DEVADDR, DP83869_RGMIIDCTL,
+ delay);
+ }
+
return ret;
}

--
2.26.2