If the serial tx/rx are floating, it can happen that bogus characters are detected on the line at boot time. This leads to U-boot accidentally thinking someone pressed a key to stop autoboot, thus stopping booting process. This can happen if the serial cable is not connected. There are hardware pull-ups on the board connected to serial cable VBUS. To solve this when the cable is not plugged, enable internal pull-ups as well for the tx/rx lines.
Signed-off-by: Eugen Hristev <eugen.hris...@microchip.com> --- arch/arm/dts/sama7g5ek.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/dts/sama7g5ek.dts b/arch/arm/dts/sama7g5ek.dts index ff9c9eb45c..3a4fdd38a5 100644 --- a/arch/arm/dts/sama7g5ek.dts +++ b/arch/arm/dts/sama7g5ek.dts @@ -122,7 +122,7 @@ pinctrl_flx3_default: flx3_default { pinmux = <PIN_PD16__FLEXCOM3_IO0>, <PIN_PD17__FLEXCOM3_IO1>; - bias-disable; + bias-pull-up; }; pinctrl_sdmmc0_cmd_data_default: sdmmc0_cmd_data_default { -- 2.25.1