On 05/24/2010 09:32 AM, Everett Wang wrote: > On Mon, May 24, 2010 at 7:36 AM, Everett Wang <[email protected]> wrote: >> On Mon, May 24, 2010 at 12:28 AM, Wolfgang Grandegger <[email protected]> >> wrote: >>> On 05/23/2010 06:19 PM, Everett Wang wrote: >>>> On Sun, May 23, 2010 at 11:46 PM, Wolfgang Grandegger >>>> <[email protected]> wrote: >>> >>>>> There are other possibilities to interact with Linux, e.g. telnet, >>>>> slogin or netcat. But it's always good to have a console. >>>>> >>>> I guess I need a USB to ethernet for these. >>> >>> Yes. >>> >>> ... >>>>> All three uarts are occupied by Linux and you cannot use them as >>>>> rtserial. First you need to release at least one of them. What Linux >>>>> config do you use for your board? >>>> >>>> I didn't do any configuration. Do you mean to config these during kernel >>>> configuration? >>> >>> Can you show us the .config of your kernel? >>> >>> Some more insights: >>> >>> I think the serial ports for the beagle boards are configured in: >>> >>> http://lxr.linux.no/#linux+v2.6.34/arch/arm/mach-omap2/serial.c >>> >>> Therein you find entries like: >>> >>> http://lxr.linux.no/#linux+v2.6.34/arch/arm/mach-omap2/serial.c#L82 >>> >>> As you can see, a regshift of 2 is used, which is not yet supported by >>> the 16550A RTDM driver. Should not be a big deal to add it, though. >>> Also, as "baud_base" you should use OMAP24XX_BASE_BAUD. >>> >>> Wolfgang. >>> >> >> Thanks for the suggestions. The .config file is attached. I will look at the >> code you pointed to today to study the configuration of the serial port. >> >> Everett >> > > Hi Wolfgang, > > I looked at the serial.c and function you pointed too. I have can't figure > out how to modify it. Could you point me to the right direction to read so > I can understand and eventually improve the serial for beagleboard? I thought > I could limit the kernel to use only one of the uart (console) by > changing function > __init omap_serial_init(void): > > void __init omap_serial_init(void) > { > int i; > > // for (i = 0; i < ARRAY_SIZE(omap_uart); i++) > // omap_serial_init_port(i); > omap_serial_init_port(2); > } > > But the kernel hangs during booting after printing this message: > > uncompressing Linux... done. > > I guess it is not that simple to let kernel not to claim the uart0 and uart1.
Yes, unfortunately. I would try to comment out the uarts you want to use for rtser in the following struct: http://lxr.linux.no/#linux+v2.6.34/arch/arm/mach-omap2/serial.c#L562 Maybe the better option is to download setserial from http://sourceforge.net/projects/setserial/files/setserial/2.17/setserial-2.17.tar.gz/download and cross-compile it for your target. Then try: # setserial /dev/ttyS2 uart none Wolfgang. _______________________________________________ Xenomai-help mailing list [email protected] https://mail.gna.org/listinfo/xenomai-help
