On 28.01.2021 10:14, Eugen Hristev wrote:

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.hristev@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 {

Applied to u-boot-atmel/master