From: Siddharth Vadapalli <s-vadapalli@ti.com>
Date: Mon, 6 Apr 2026 12:45:57 +0000 (+0530)
Subject: net: phy: dp83867: default to 2ns delay if unspecified in device-tree
X-Git-Tag: v2026.07-rc2~15^2~17
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=e86d1c0b883e1be99f416089012af36219158c08;p=thirdparty%2Fu-boot.git

net: phy: dp83867: default to 2ns delay if unspecified in device-tree

Since Linux commit c360eb0c3ccb ("dt-bindings: net: ethernet-controller:
Add informative text about RGMII delays"), the interpretation of RGMII
delays has changed. Prior to the commit, the RGMII Variant among "rgmii",
"rgmii-id", "rgmii-rxid" and "rgmii-txid" clearly specified whether it is
the MAC or the PHY that "should" add the delay. However, post that commit,
the RGMII Variant only specifies whether or not there is a delay on the
PCB traces between the MAC and the PHY, leaving it open as to who adds the
delay.

Hence, instead of enforcing the existence of the device-tree properties
"ti,rx-internal-delay" and "ti,tx-internal-delay", default to a delay
of 2ns, while continuing to override this delay with the aforementioned
properties, if they exist in the device-tree.

This is in line with the Linux driver implementation updated by commit
6bf78849371d ("net: phy: dp83867: use 2ns delay if not specified in DTB").

Signed-off-by: Siddharth Vadapalli <s-vadapalli@ti.com>
Reviewed-by: Anshul Dalal <anshuld@ti.com>
---

diff --git a/drivers/net/phy/dp83867.c b/drivers/net/phy/dp83867.c
index 7ce03b59b6a..ebed61de133 100644
--- a/drivers/net/phy/dp83867.c
+++ b/drivers/net/phy/dp83867.c
@@ -203,32 +203,24 @@ static int dp83867_of_init(struct phy_device *phydev)
 				"Should be 'rgmii-id' to use internal delays\n");
 	}
 
-	/* RX delay *must* be specified if internal delay of RX is used. */
+	dp83867->rx_id_delay = DP83867_RGMIIDCTL_2_00_NS;
 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_RXID) {
 		ret = ofnode_read_u32(node, "ti,rx-internal-delay",
 				      &dp83867->rx_id_delay);
-		if (ret) {
-			pr_debug("ti,rx-internal-delay must be specified\n");
-			return ret;
-		}
-		if (dp83867->rx_id_delay > DP83867_RGMII_RX_CLK_DELAY_MAX) {
+		if (!ret && dp83867->rx_id_delay > DP83867_RGMII_RX_CLK_DELAY_MAX) {
 			pr_debug("ti,rx-internal-delay value of %u out of range\n",
 				 dp83867->rx_id_delay);
 			return -EINVAL;
 		}
 	}
 
-	/* TX delay *must* be specified if internal delay of RX is used. */
+	dp83867->tx_id_delay = DP83867_RGMIIDCTL_2_00_NS;
 	if (phydev->interface == PHY_INTERFACE_MODE_RGMII_ID ||
 	    phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
 		ret = ofnode_read_u32(node, "ti,tx-internal-delay",
 				      &dp83867->tx_id_delay);
-		if (ret) {
-			debug("ti,tx-internal-delay must be specified\n");
-			return ret;
-		}
-		if (dp83867->tx_id_delay > DP83867_RGMII_TX_CLK_DELAY_MAX) {
+		if (!ret && dp83867->tx_id_delay > DP83867_RGMII_TX_CLK_DELAY_MAX) {
 			pr_debug("ti,tx-internal-delay value of %u out of range\n",
 				 dp83867->tx_id_delay);
 			return -EINVAL;