topic System keeps reboot due to UART RX pin left floating ls1021a in Layerscape

System keeps reboot due to UART RX pin left floating ls1021a

jiye — Sun, 24 May 2020 17:54:03 GMT

Hi,

My system keeps reboot due to the UART RX keep sending nonsense characters during boot, in my circuit I left this pin as floating but I dont want to change the hardware layout as it will cost a lot.

I still want to use RX for debugging and I dont want to disable to affect my debugging.

The driver is pl011

(1) Is there way to fix this in a software way? disable this driver at bootrom and re-enable them back

I just want to find a way to disable the RX during bootrom then enable it back

Re: System keeps reboot due to UART RX pin left floating ls1021a

ufedor — Wed, 27 May 2020 07:18:12 GMT

Which exactly "UART RX" is in question?

What does it mean: "The driver is pl011"?

What does it mean: "My system keeps reboot"?

Please provide detailed technical description of the problem including the following attachments:

1) the processor connection schematics as searchable PDF

2) digital scope traces showing behaviour of the processor's reset signals corresponding to the QorIQ LS1021A Reference Manual, Figure 4-1. Power-on reset sequence