Hi Bob, rwarner wrote:
Ok with respect to the 'linux' kernel i am unlearned in this regard of kernel debug information. Is there a configuration item in the build of the kernel which produces debug information in the vmlinux file? Or do i need to find the build sequence and add -g option to the Makefile's compile and linker flags?
If you are using a 2.4.x kernel then you want the CONFIG_DEBUG_INFO switch for arm turned on.
Also, i'm getting printk function execution and hoping i can set this output to send out over one of the serial ports on this uC (Atmel ARM7). Does the uClinux printk output over a 'standard' uC serial connection?
It can. The port you want output on needs to be the "console".
Ok, reading archive i see the 'kernel command line' needs to get the location of the serial connection (e.g. /dev/ttyS0).
That is the typical way to do it. Though a serial driver code can define a port to be the console as default too.
How or where does the kernel command line get set during startup of the kernel?
Varies from board to board and architecture to architecture.
I'm assuming some memory location. Noted M68K archive mail Looked for a 'config.c' file for the arm arch but couldn't find it for the ARM7.
ARM has traditionally use ARM TAGS at a specific memory address for passing a command line to the kernel. The arm boot documentation mye be helpful: linux-2.6.x/Documentation/arm/Booting
ok nm, another archive response says printk goes to a buffer in memory.
It does. That doesn't preclude it coming out a serial port as well :-)
:| Is it not possible setup a serial connection early on and output this information during kernel startup execution? The another archive message indicates otherwise "How to bind console to early printk'. If this is the case then i do appear to have the console setup for early printk.
This is the issue. "console" decvies (eg a serial port) are not setup until well into the boot sequence. So you won't get early trace. Once consoles are registered then the current printk buffer can be dumped out it. From then on printk output will go to the console through the polled console routines of the serial driver.
A few questions still remain on when printk's will output to the serial console. Immediately on the first printk or after some point in kernel initialization sequence?
Yes, after the console driver part of the serial driver as been inited and registered.
And does a kernel command line come into play here and where is the kernel command line for the ARM7?
I don't recall the setup of the ARM7 code now (and this will depend on which kernel version you are using) but it may not have target command line support yet. You can always compile in a command line. Hope that helps. Regards Greg ------------------------------------------------------------------------ Greg Ungerer -- Chief Software Dude EMAIL: [EMAIL PROTECTED] Secure Computing Corporation PHONE: +61 7 3435 2888 825 Stanley St, FAX: +61 7 3891 3630 Woolloongabba, QLD, 4102, Australia WEB: http://www.SnapGear.com _______________________________________________ uClinux-dev mailing list [email protected] http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by [email protected] To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
