Xilinx Zynq console rx not working

[Kinsey Moore]

On 8/13/2021 03:05, Chris Johns wrote:
> Hi,
>
> I am bring up a major app on RTEMS 6 and LibBSD on custom Zynq hardware and I am
> not getting any receive interrupts from the console UART. The same hardware
> works with RTEMS 4.11 and RTEMS 5.
>
> I also do not see any console input with qemu and I thought this was something
> in qemu but I am now not so sure.
>
> Anyone else seeing this issue?
>
> There has been a lot of playing with the Zynq UART driver recently.

I just went through and backed out all those changes you mentioned back 
to when the polled-only driver was split out and I still don't have 
functionality on Zynq under QEMU. Testing using fileio.exe, things are 
partially functional until I revert the change that enabled 
set_attributes. After the commit that enables set_attributes for the 
zynq UART, fileio produces output waiting for user input and will accept 
the first character to open the menu, but accepts no further input. 
Before that commit, the fileio test doesn't produce the expected output.

A full bisect would probably provide more accurate results, but this is 
what I could do quickly.

Note that ZynqMP fileio works on QEMU with current code and is fully 
operational. It is almost certainly the exact same emulated peripheral 
in QEMU and the hardware is supposed to be very close if not identical 
as well.


Kinsey