Starting with:
bcf3440c6dd7 ("net: phy: micrel: add phy-mode support for the KSZ9031 PHY")
the micrel phy driver started respecting phy-mode for the KSZ9031 PHY.
At least with kernel v5.8 configuration provided by this fixup was
overwritten by the micrel driver.
This fixup was providing following configuration:
RX path: 2.58ns delay
rx -0.42 (left shift) + rx_clk +0.96ns (right shift) =
1,38 + 1,2 internal RX delay = 2.58ns
TX path: 0.96ns delay
tx (no delay) + tx_clk 0.96ns (right shift) = 0.96ns
This configuration is outside of the recommended RGMII clock skew delays
and about in the middle of: rgmii-idrx and rgmii-id
Since most embedded systems do not have enough place to introduce
significant clock skew, rgmii-id is the way to go.
In case this patch breaks network functionality on your system, build
kernel with enabled MICREL_PHY. If it is still not working then try
following device tree options:
1. Set (or change) phy-mode in DT to:
phy-mode = "rgmii-id";
This actives internal delay for both RX and TX.
1. Set (or change) phy-mode in DT to:
phy-mode = "rgmii-idrx";
This actives internal delay for RX only.
3. Use following DT properties:
phy-mode = "rgmii";
txen-skew-psec = <0>;
rxdv-skew-psec = <0>;
rxd0-skew-psec = <0>;
rxd1-skew-psec = <0>;
rxd2-skew-psec = <0>;
rxd3-skew-psec = <0>;
rxc-skew-psec = <1860>;
txc-skew-psec = <1860>;
This activates the internal delays for RX and TX, with the value as
the fixup that is removed in this patch.
Signed-off-by: Oleksij Rempel <o.rem...@pengutronix.de>
---
arch/arm/boot/dts/imx6q-dmo-edmqmx6.dts | 2 +-
arch/arm/mach-imx/mach-imx6q.c | 23 -----------------------
2 files changed, 1 insertion(+), 24 deletions(-)
diff --git a/arch/arm/boot/dts/imx6q-dmo-edmqmx6.dts
b/arch/arm/boot/dts/imx6q-dmo-edmqmx6.dts
index fa2307d8ce86..c713ac03b3b9 100644
--- a/arch/arm/boot/dts/imx6q-dmo-edmqmx6.dts
+++ b/arch/arm/boot/dts/imx6q-dmo-edmqmx6.dts
@@ -112,7 +112,7 @@ flash: m25p80@0 {
&fec {
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_enet>;
- phy-mode = "rgmii";
+ phy-mode = "rgmii-id";
phy-reset-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
phy-supply = <&vgen2_1v2_eth>;
status = "okay";
diff --git a/arch/arm/mach-imx/mach-imx6q.c b/arch/arm/mach-imx/mach-imx6q.c
index 703998ebb52e..78205f90da27 100644
--- a/arch/arm/mach-imx/mach-imx6q.c
+++ b/arch/arm/mach-imx/mach-imx6q.c
@@ -40,27 +40,6 @@ static int ksz9021rn_phy_fixup(struct phy_device *phydev)
return 0;
}
-static void mmd_write_reg(struct phy_device *dev, int device, int reg, int val)
-{
- phy_write(dev, 0x0d, device);
- phy_write(dev, 0x0e, reg);
- phy_write(dev, 0x0d, (1 << 14) | device);
- phy_write(dev, 0x0e, val);
-}
-
-static int ksz9031rn_phy_fixup(struct phy_device *dev)
-{
- /*
- * min rx data delay, max rx/tx clock delay,
- * min rx/tx control delay
- */
- mmd_write_reg(dev, 2, 4, 0);
- mmd_write_reg(dev, 2, 5, 0);
- mmd_write_reg(dev, 2, 8, 0x003ff);
-
- return 0;
-}
-
/*
* fixup for PLX PEX8909 bridge to configure GPIO1-7 as output High
* as they are used for slots1-7 PERST#
@@ -152,8 +131,6 @@ static void __init imx6q_enet_phy_init(void)
if (IS_BUILTIN(CONFIG_PHYLIB)) {
phy_register_fixup_for_uid(PHY_ID_KSZ9021, MICREL_PHY_ID_MASK,
ksz9021rn_phy_fixup);
- phy_register_fixup_for_uid(PHY_ID_KSZ9031, MICREL_PHY_ID_MASK,
- ksz9031rn_phy_fixup);
phy_register_fixup_for_uid(PHY_ID_AR8031, 0xffffffef,
ar8031_phy_fixup);
phy_register_fixup_for_uid(PHY_ID_AR8035, 0xffffffef,
--
2.30.0
