2008-10-14 05:18:25     No output from userspace (using serial console)

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2008-10-14 05:18:25     No output from userspace (using serial console)

Thomas Langås (NORWAY)

Message: 63631   


So I finally managed to boot my linuxkernel, and I guess control is handed over to userspace as it should since kernel console messages are "normal".


My problem now seems to be that I get no output from userspace over the console.  Does the /bin/init (from user/init/ in svn-tree) use console by default, if it's enabled when booting the linux kernel?  And, I guess the console in the linux kernel uses the std serial-driver, so if I get output during bootup, it's ok to assume that I should get output in userspace given that everything else is ok?  (I'm using half-duplex RS-485, and I managed to get this working correctly with the serial-driver after defining RTS-flag as GPIO-pin).


-- Thomas




2008-10-14 06:08:35     Re: No output from userspace (using serial console)

Mike Frysinger (UNITED STATES)

Message: 63637   


what userspace does depends on your configuration.  if your configuration uses simpleinit and tells it spawn a console shell (the default in ADI configs), then a shell will automatically launch on the primary console.


you also have to keep in mind that when the shell launches, it tends to muck with termios settings, so you need to check that your console declares it right and that the shell doesnt do what you dont expect.  otherwise you'll probably need to chain through getty.


just telnet into the board and review things.