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Altera_Forum's avatar
Altera_Forum
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14 years ago

Linux freeze JTAG problem

Hi all,

I've got a problem on my board. Whereas I selected in Device Drivers-> Character devices -> Serial drivers :

[*] Bypass output when no connection

My uClinux freeze after 5 minutes of perfectly running.

When I plug the JTAG and do a " nios2-terminal " on my computer, all the " dmesg " is printed on the console and the uClinux comes backs to life.

It looks like a fifo full and as soon as I empty the the fifo everything is fine.

Does anybody got an idea ?

Thanks in advance.

9 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I didn't found what to do ...

    Does anybody can help me. Nobody got this problem ?

    Thanks
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    JTAG serial ports having this type of problems. xilinx does the same without linux also. the option "Bypass output when no connection" should actually solve this problem, I do not know.

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Thank you neolux.

    Does a Guru have solution for my problem ?

    Thanks
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I just ran into this problem too. It works most of the time, when only the normal boot messages get printed to the console. But if something happens that prints out a lot of messages, such as the OOM killer, Linux hangs until I connect with a nios2-terminal. I'm looking through the altera_jtaguart source to try to track down the problem, but any help would be appreciated.

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Please tell me what solution did you found to solve this problem !

    Thanks
  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Hello guys,

    i had this problem either but without using uCLinux.

    The same problem appears when using the µC/OS-II operating system.

    There the problem lies within the altera hal.

    I could fix it, using the following defines symbols (for the preprocessor):

    ALTERA_AVALON_JTAG_UART_BUF_LEN=8192

    This increases the buffer.

    And within the source-code i used this ioctl to setup the non-blocking mode:

    fcntl(STDOUT_FILENO, F_SETFL, O_NONBLOCK);

    fcntl(STDERR_FILENO, F_SETFL, O_NONBLOCK);

    I don't know if this sollution can be ported to uCLinux?!

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    I was running into this problem with JTAG, and Linux wouldn't boot from flash without a console, so I am now using a netconsole to work around the problems.

    menuconfig > Device Driver > Network Device Support > Network console logging support

    see linux-2.6/Documentation/networking/netconsole.txt