[PATCH 11/14] arm64: zynqmp: Disable Tri-state for MIO38 Pin

From: Michal Simek
Date: Mon Jan 08 2024 - 10:43:50 EST


From: Tejas Bhumkar <tejas.arvind.bhumkar@xxxxxxx>

gpio38 is used in SOM's kv260 to reset the Ethernet PHY.
At present, HW reset is not working properly as Tri-state 
is enabled for MIO38, causing inappropriate PHY register reads.

Disabled Tri-state for MIO38 to make HW reset work.

Tri-state disable :
ZynqMP> md 0xFF180208 2
ff180208: 00bfe7a3 00000540

Tri-state enable :
ZynqMP> md 0xFF180208 2
ff180208: 00bfe7e3 00000540

Signed-off-by: Tejas Bhumkar <tejas.arvind.bhumkar@xxxxxxx>
Signed-off-by: Michal Simek <michal.simek@xxxxxxx>
---

.../boot/dts/xilinx/zynqmp-sck-kv-g-revA.dtso | 25 +++++++++++++++++++
.../boot/dts/xilinx/zynqmp-sck-kv-g-revB.dtso | 25 +++++++++++++++++++
2 files changed, 50 insertions(+)

diff --git a/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revA.dtso b/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revA.dtso
index b7b94254cc09..585b5845a1f4 100644
--- a/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revA.dtso
+++ b/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revA.dtso
@@ -169,6 +169,25 @@ phy0: ethernet-phy@1 {
&pinctrl0 {
status = "okay";

+ pinctrl_gpio0_default: gpio0-default {
+ conf {
+ groups = "gpio0_38_grp";
+ bias-pull-up;
+ power-source = <IO_STANDARD_LVCMOS18>;
+ };
+
+ mux {
+ groups = "gpio0_38_grp";
+ function = "gpio0";
+ };
+
+ conf-tx {
+ pins = "MIO38";
+ bias-disable;
+ output-enable;
+ };
+ };
+
pinctrl_uart1_default: uart1-default {
conf {
groups = "uart1_9_grp";
@@ -324,6 +343,12 @@ mux {
};
};

+&gpio {
+ status = "okay";
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_gpio0_default>;
+};
+
&uart1 {
status = "okay";
pinctrl-names = "default";
diff --git a/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revB.dtso b/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revB.dtso
index 1446c2b19de7..037f0941ba0b 100644
--- a/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revB.dtso
+++ b/arch/arm64/boot/dts/xilinx/zynqmp-sck-kv-g-revB.dtso
@@ -152,6 +152,25 @@ phy0: ethernet-phy@1 {
&pinctrl0 {
status = "okay";

+ pinctrl_gpio0_default: gpio0-default {
+ conf {
+ groups = "gpio0_38_grp";
+ bias-pull-up;
+ power-source = <IO_STANDARD_LVCMOS18>;
+ };
+
+ mux {
+ groups = "gpio0_38_grp";
+ function = "gpio0";
+ };
+
+ conf-tx {
+ pins = "MIO38";
+ bias-disable;
+ output-enable;
+ };
+ };
+
pinctrl_uart1_default: uart1-default {
conf {
groups = "uart1_9_grp";
@@ -307,6 +326,12 @@ mux {
};
};

+&gpio {
+ status = "okay";
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_gpio0_default>;
+};
+
&uart1 {
status = "okay";
pinctrl-names = "default";
--
2.36.1