PCIe AER generates no interrupts on host (ZynqMP)

[Stefan Roese <sr@denx.de>]

Hi,

I'm trying to get the Kernel PCIe AER infrastructure to work on my
ZynqMP based system. E.g. handle the events (correctable, uncorrectable
etc). In my current tests, no AER interrupt is generated though. I'm
currently using the "surprise down error status" in the uncorrectable
error status register of the connected PCIe switch (PLX / Broadcom
PEX8718). Here the bit is correctly logged in the PEX switch
uncorrectable error status register but no interrupt is generated
to the root-port / system. And hence no AER message(s) reported.

Does any one of you have some ideas on what might be missing? Why are
these events not reported to the PCIe rootport driver via IRQ? Might
this be a problem of the missing MSI-X support of the ZynqMP? The AER
interrupt is connected as legacy IRQ:

cat /proc/interrupts | grep -i aer
  58:          0          0          0          0  nwl_pcie:legacy   0 
Level     PCIe PME, aerdrv

BTW: This was tested on v5.10 and recent v5.16-rc6.

Thanks,
Stefan