Petalinux driver problem for AXI Interrupt Controller on Zynq

Question

We are trying to use the AXI interrupt controller because we have more than 16 uarts. We are running Petalinux 2013.10 and the device tree is attached. 
When a UART is connected directly without using the AXI interrupt controller it seems to work as expected; the interrupt fires and all data gets through at any baud rate. However, if the interrupt is going through the AXI interrupt controller the interrupt fires but we consistently get an overrun if we send more than 16 bytes at 115200 baud. Note that this is when there is only data on that one port. This would seem to imply that the interrupt is taking so long that the UART buffer overflows. 
The kernel output (attached) says that all the uarts going through interrupt controllers (uarts 1-32) are on IRQ 0, which seems wrong. I would expect a different IRQ number for each of the two AXI interrupt controllers.
From this forum post, it looks like the driver is meant for microblaze but they got it working on Zynq:
http://forums.xilinx.com/t5/Embedded-Linux/Petalinux-driver-for-AXI-Interrupt-Controller-core/m-p/525305#M10742
Unfortunately they didn't specify what they did to get it working.
Has anyone successfully used the AXI Interrupt Controller on a Zynq or other non-microblaze architecture?
Thanks,
Jaymes

Answer 1

I really appreciate your help. I'm getting closer to a solution.
I ORed all 33 of our interrupts together using a utility logic block. I added interrupt settings to each uart device tree entry:
interrupt-parent = <&ps7_scugic_0>;
interrupts = <0 57 4>;
This results in all uarts at IRQ 89, which I think is correct. I also tried interrupts = <1 73 4> with the same result.
It seems that all uarts are responding to interrupts, but only the last (33rd) uart is generating interrupts. If I try to send/receive data on any uart other than 33 it won't be sent/received until there is activity on uart 33. Any ideas?
vanmierlo wrote:
Further the kernel driver needs to have IRQF_SHARED defined and some other fixes as discussed int this issue:
https://github.com/Xilinx/linux-xlnx/issues/24
Maarten
This is supported with an "IRQ sharing" kernel option in the 16550 uart driver.
Thanks,
Jaymes