Trouble on PXA w/kernel command-line

Hello:

I have u-boot up and running on my PXA-255 based custom board, and the linux kernel is booting and running. GREAT!

The problem is that the command-line (as set in the u-boot environment variable) is not getting to the kernel. This isn't a terribly serious problem but it's time for me to sort this out.

Please let me know what would be the best way to debug this problem, and where I ought to look for the problem in u-boot/kernel code.

Thanks in advance,
craig vanderborgh
voxware incorporated

Is CONFIG_CMDLINE_TAG selected in your board config file?

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Houston, Tranquillity Base here.  The Eagle has landed.
                                                    -- Neil Armstrong

Hello Wolfgang!

Yes, it is most definitely set. Could you possibly describe how command-line passing is *supposed* to work and then I think I can fix it...

Thanks again for everything!!

craig

See setup_commandline_tag() and do_bootm_linux() in lib_arm/armlinux.c

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
You are only young once, but you can stay immature indefinitely.

Hello Wolfgang:

It turns out that u-boot's handling of the command line is PERFECT. Absolutely spot-on. The trouble was on the receiving end of the command line in my kernel. My machine descriptor (in my processor setup C code) looked like this:

MACHINE_START(BITSYX, "Voxware/ADS BitsyX Lite")

	BOOT_MEM(0xa0000000, 0x40000000, io_p2v(0x40000000))
	MAPIO(bitsyx_map_io)
	INITIRQ(bitsyx_init_irq)

MACHINE_END

It lacked the "BOOT_PARAMS" macro that tells the kernel where in memory to look for the command line. Once I added a "BOOT_PARAMS" to my MACHINE descriptor everything works perfectly:

MACHINE_START(BITSYX, "Voxware/ADS BitsyX Lite")

        BOOT_PARAMS(0xa0000100)
	BOOT_MEM(0xa0000000, 0x40000000, io_p2v(0x40000000))
	MAPIO(bitsyx_map_io)
	INITIRQ(bitsyx_init_irq)

MACHINE_END

I am sorry to bother you with such trivialities, but they are UNDOCUMENTED and not at all obvious to people who don't regularly do Linux kernel work - like myself.

Thanks a MILLION.

Regards,
craig

Then please help improving the documentation. For example, you could add an entry to the Linux FAQ section in the DULG - it takes no more than 10 minutes, and might help others.

Best regards,

Wolfgang Denk

Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"Love your country but never trust its government."
- from a hand-painted road sign in central Pennsylvania