Linux on SBC8260

Linux on SBC8260

[Dejan Jovanovic]

Hello,

I am trying to run Linux on a EST's SBC8260 board.

First thing I have tried is using ppcboot to load the Linux kernel image.
- ppcboot version is 1.1.6
- Linux version is 2.4.4 - the one that comes with ELDK from Wolfgang. (as a
side question - is it enough if I do the 'make est8260_config' or I need to do
menuconfig as well after that?)

First I have used the Linux kernel image, one in arch/ppc/coffboot and converted
using mkimage tool (with parameters -a 0x0000_0000 and -e 0x0000_0000)
ppcboot is running on my board and I have loaded linux image (the converted
one).
After that I have executed ppcboot 'bootm' command, and got the message
'Loading Kernel Image OK' -- (?? this is strange though - should it not say here
Uncompressing Kernel Image ?)
After that nothing happens on my serial console.

So I tried to use the BDI2000 to debug this.
I skipped the ppcboot, and loaded the Linux Kernel Image (now the one from
arch/ppc/mbxboot) into the RAM directly.
After setting the PC and doing a 'go' I got the message that the 'Target has
entered debug state' with 'Debug Entry cause (reserved 0)' I am not sure how
much this helps, but by doing a 'objdump' on the image file and comparing the
last PC after the 'go' command, it seems to be stuck somewhere is 'serial_init'
section.

BTW, I also tried compiling the Linux Kernel with '-g -ggdb' option. Should not
the image size in case I compile with and without this options differ, because
when I compare images in these two cases they are the same. I wanted to use this
for gdb debugging.

What am I doing wrong in this process(es)?

Regards and thanks
Dejan


** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/

Re: Linux on SBC8260

[Wolfgang Denk]

In message <00e301c243ac$14182dc0$db00000a@dejanj> you wrote:
>
> I am trying to run Linux on a EST's SBC8260 board.
>
> First thing I have tried is using ppcboot to load the Linux kernel image.
> - ppcboot version is 1.1.6
> - Linux version is 2.4.4 - the one that comes with ELDK from Wolfgang. (as a
> side question - is it enough if I do the 'make est8260_config' or I need to do
> menuconfig as well after that?)

The general procedure is always the same:

	make est8260_config
	make oldconfig              or make menuconfig
	make dep
	make pImage

"make oldconfig" is good if you don't  want  to  change  the  default
configuration  (which is probably a good idea to get a system running
first), while "make menuconfig" is goot to modify  the  configuration
to  your  specific  needs (you should know what you're doing then, of
course).

> First I have used the Linux kernel image, one in arch/ppc/coffboot and converted
> using mkimage tool (with parameters -a 0x0000_0000 and -e 0x0000_0000)

This is done automatically with "make pImage".

> After that I have executed ppcboot 'bootm' command, and got the message
> 'Loading Kernel Image OK' -- (?? this is strange though - should it not say here
> Uncompressing Kernel Image ?)

This depends. If you use an uncompressed  kernel  image  (build  with
mkimage  option  "-C  none")  you'll  see  " Loading %s ... ", with a
compressed image you'll get " Uncompressing %s ... ".

> After that nothing happens on my serial console.

Probably you made some errors when building the image  -  that's  why
there is the "pImage" make target, to provide a working solution.

> So I tried to use the BDI2000 to debug this.
> I skipped the ppcboot, and loaded the Linux Kernel Image (now the one from
> arch/ppc/mbxboot) into the RAM directly.
> After setting the PC and doing a 'go' I got the message that the 'Target has

You cannot (simply) do this.  The  Linux  kernel  expects  a  lot  of
hardware initialization before it can run, and even then it expects a
couple of arguments passed to it.

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
EMACS belongs in <sys/errno.h>: Editor too big!

** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/