Author Topic: AXI UART16550 interrupts not seen in petalinux 2018.2  (Read 157 times)

shaikhkh

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AXI UART16550 interrupts not seen in petalinux 2018.2
« on: March 09, 2021, 03:19:25 PM »
Hi,

I am using te0720-03-2IF module and trying to run petalinux 2018.2 on our board. I am able to successfully boot and have the uart console. Most of the peripherals work. I am having issue with our 'AXI UART16550 2.0' IP's. We are using 8 UART IP's in our PL connected to IRQ_F2P on the zynq PS. The same design I have also used with QNX where all the AXI UART IPs work without any problem, so I am sure that the vivado design is correct.

I have started with the reference petalinux project from trenz and then updated the hardware description using "petalinux-config --get-hw-description".
I have also updated the number of 16550 uarts in kernel to 8.
After building my project, I could also see that the uart entries are populated properly in the pl.dtsi file. I have also rechecked the system.dtb (converted to system.dts) and see that all the uarts are present. I am posting an example uart entry below

      Serial_UARTs_axi_uart16550_2: serial@43c20000 {
         clock-frequency = <100000000>;
         clock-names = "s_axi_aclk";
         clocks = <&misc_clk_0>;
         compatible = "xlnx,xps-uart16550-2.00.a", "ns16550a";
         current-speed = <115200>;
         device_type = "serial";
         interrupt-names = "ip2intc_irpt";
         interrupt-parent = <&intc>;
         interrupts = <0 29 4>;
         port-number = <6>;
         reg = <0x43c20000 0x10000>;
         reg-offset = <0x1000>;
         reg-shift = <2>;
         xlnx,external-xin-clk-hz = <0x17d7840>;
         xlnx,external-xin-clk-hz-d = <0x19>;
         xlnx,has-external-rclk = <0x0>;
         xlnx,has-external-xin = <0x0>;
         xlnx,is-a-16550 = <0x1>;
         xlnx,s-axi-aclk-freq-hz-d = "100.0";
         xlnx,use-modem-ports = <0x1>;
         xlnx,use-user-ports = <0x1>;
};

Once booted, I see in dmesg that all uarts are probed at runtime and the drivers attached
root@fcc_te0720_project:~# dmesg | grep 16550
Serial: 8250/16550 driver, 8 ports, IRQ sharing disabled
43c50000.serial: ttyS0 at MMIO 0x43c51000 (irq = 53, base_baud = 6250000) is a 16550A
43c10000.serial: ttyS1 at MMIO 0x43c11000 (irq = 54, base_baud = 6250000) is a 16550A
43ca0000.serial: ttyS2 at MMIO 0x43ca1000 (irq = 55, base_baud = 6250000) is a 16550A
43cb0000.serial: ttyS3 at MMIO 0x43cb1000 (irq = 56, base_baud = 6250000) is a 16550A
43c70000.serial: ttyS4 at MMIO 0x43c71000 (irq = 57, base_baud = 6250000) is a 16550A
43c20000.serial: ttyS5 at MMIO 0x43c21000 (irq = 58, base_baud = 6250000) is a 16550A
43c40000.serial: ttyS6 at MMIO 0x43c41000 (irq = 59, base_baud = 6250000) is a 16550A
43c60000.serial: ttyS7 at MMIO 0x43c61000 (irq = 60, base_baud = 6250000) is a 16550A

The problem is that in /proc/interrupt I don't see any of the UART interrupts and doing a loop on RX and TX of the uart, I dont see any data coming

root@fcc_te0720_project:~# cat /proc/interrupts
           CPU0       CPU1       
 16:          0          0     GIC-0  27 Edge      gt
 17:          0          0     GIC-0  43 Level     ttc_clockevent
 18:      67148      58283     GIC-0  29 Edge      twd
 19:          0          0     GIC-0  37 Level     arm-pmu
 20:          0          0     GIC-0  38 Level     arm-pmu
 21:         43          0     GIC-0  39 Level     f8007100.adc
 25:          0          0     GIC-0  57 Level     cdns-i2c
 26:          8          0     GIC-0  80 Level     cdns-i2c
 28:          0          0     GIC-0  35 Level     f800c000.ocmc
 29:        315          0     GIC-0  59 Level     xuartps
 30:          0          0     GIC-0  58 Level     e0006000.spi
 31:          9          0     GIC-0  51 Level     e000d000.spi
 32:        874          0     GIC-0  54 Level     eth0
 33:          0          0     GIC-0  77 Level     eth1
 34:        330          0     GIC-0  56 Level     mmc0
 35:        471          0     GIC-0  79 Level     mmc1
 36:          0          0     GIC-0  45 Level     f8003000.dmac
 37:          0          0     GIC-0  46 Level     f8003000.dmac
 38:          0          0     GIC-0  47 Level     f8003000.dmac
 39:          0          0     GIC-0  48 Level     f8003000.dmac
 40:          0          0     GIC-0  49 Level     f8003000.dmac
 41:          0          0     GIC-0  72 Level     f8003000.dmac
 42:          0          0     GIC-0  73 Level     f8003000.dmac
 43:          0          0     GIC-0  74 Level     f8003000.dmac
 44:          0          0     GIC-0  75 Level     f8003000.dmac
 45:          0          0     GIC-0  40 Level     f8007000.devcfg
 51:          0          0     GIC-0  53 Level     e0002000.usb
 52:          0          0     GIC-0  41 Edge      f8005000.watchdog
IPI1:          0          0  Timer broadcast interrupts
IPI2:      41535      42405  Rescheduling interrupts
IPI3:        213        200  Function call interrupts
IPI4:          0          0  CPU stop interrupts
IPI5:          0          0  IRQ work interrupts
IPI6:          0          0  completion interrupts
Err:          0

I am not sure what I am missing. I would be very grateful if someone can help.

Best Regards,
Khizer

JH

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Re: AXI UART16550 interrupts not seen in petalinux 2018.2
« Reply #1 on: March 10, 2021, 08:16:51 AM »
Hi,
sorry I didn't work with this IP from Xilinx until now. So I can't help much

What you ask is a more Xilinx specific question, maybe you should write your questions also on the Xilinx forum.

Or check for example:
https://forums.xilinx.com/t5/Embedded-Linux/UART-16550-not-seen-as-a-device-in-dev-in-Petalinux/td-p/1001421
 --> maybe you has the same problem
https://xilinx-wiki.atlassian.net/wiki/spaces/A/pages/18842080/AXI+UART+16550+standalone+driver
...

br
John

shaikhkh

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Re: AXI UART16550 interrupts not seen in petalinux 2018.2
« Reply #2 on: March 10, 2021, 08:58:41 AM »
Hi,

Thank you for your reply.
I will post it on the Xilinx forum.

Best Regards,
Khizer