arm64: zynqmp: Disable Tri-state for MIO38 Pin
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@amd.com>
Link: https://lore.kernel.org/r/20231020050622.972750-1-tejas.arvind.bhumkar@amd.com
Signed-off-by: Michal Simek <michal.simek@amd.com>
diff --git a/arch/arm/dts/zynqmp-sck-kv-g-revA.dtso b/arch/arm/dts/zynqmp-sck-kv-g-revA.dtso
index 22e7d68..c4f1da9 100644
--- a/arch/arm/dts/zynqmp-sck-kv-g-revA.dtso
+++ b/arch/arm/dts/zynqmp-sck-kv-g-revA.dtso
@@ -190,6 +190,25 @@
&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";
@@ -345,6 +364,12 @@
};
};
+&gpio {
+ status = "okay";
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_gpio0_default>;
+};
+
&uart1 {
status = "okay";
pinctrl-names = "default";