[PATCH 5.9 100/252] ARM: dts: imx6q-prti6q: fix PHY address

Greg Kroah-Hartman
2020-11-23T13:15:23Z

From: Oleksij Rempel <o.rempel@pengutronix.de>

[ Upstream commit e402599e5e5e0b2758d7766fd9f6d7953d4ccd85 ]

Due to bug in the bootloader, the PHY has floating address and may
randomly change on each PHY reset. To avoid it, the updated bootloader
with the following patch[0] should be used:

| ARM: protonic: disable on-die termination to fix PHY bootstrapping
|
| If on-die termination is enabled, the RXC pin of iMX6 will be pulled
| high. Since we already have an 10K pull-down on board, the RXC level on
| PHY reset will be ~800mV, which is mostly interpreted as 1. On some
| reboots we get 0 instead and kernel can't detect the PHY properly.
|
| Since the default 0x020e07ac value is 0, it is sufficient to remove this
| entry from the affected imxcfg files.
|
| Since we get stable 0 on pin PHYADDR[2], the PHY address is changed from
| 4 to 0.

With latest bootloader update, the PHY address will be fixed to "0".

[0] https://git.pengutronix.de/cgit/barebox/commit/?id=93f7dcf631edfcda19e7757b28d66017ea274b81

Fixes: 0d446a505592 ("ARM: dts: add Protonic PRTI6Q board")
Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/arm/boot/dts/imx6q-prti6q.dts | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/boot/dts/imx6q-prti6q.dts b/arch/arm/boot/dts/imx6q-prti6q.dts
index de6cbaab8b499..671bb3a6665d8 100644
--- a/arch/arm/boot/dts/imx6q-prti6q.dts
+++ b/arch/arm/boot/dts/imx6q-prti6q.dts
@@ -213,8 +213,8 @@
#size-cells = <0>;

/* Microchip KSZ9031RNX PHY */
- rgmii_phy: ethernet-phy@4 {
- reg = <4>;
+ rgmii_phy: ethernet-phy@0 {
+ reg = <0>;
interrupts-extended = <&gpio1 28 IRQ_TYPE_LEVEL_LOW>;
reset-gpios = <&gpio1 25 GPIO_ACTIVE_LOW>;
reset-assert-us = <10000>;
--
2.27.0