Hi:
I use the AM625-SK to validate the WKUP_UART0. our customer would like to use the WKUP_UART0 to access other devices, and A53 core will use WKUP_UART0 to do it.
I enable WKUP_UART0 on A53 dts file.
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I try tx data on WKUP_UART0, but it spend lot of time to do it, and the data is not output on the tx_pin.
Reproduce Step:
[2022-06-10 12:03:42.216] #> echo a > /dev/ttyS0
[2022-06-10 12:04:17.862] #>
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Debug:
1. In the console stop time, i try to ssh to the board, it is working. it seen the board is not real hangup.
2. I double check the /proc/interrupt.
When i press "echo a > /dev/ttyS0", the interrupt will +1.
When the console come back, then the interrupt will +1 again.
3. I validate the MCU_UART0.
when i press "echo a > /dev/ttyS1", then interrupt will +2, and console come back immediately.
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Question:
* it seems the WKUP_UART0 will wait for the second interrupt. what will it be?
* Is there a fix for the issue?
BR
Dave.hu
