[U-Boot-Users] Linux Bring up problem

[Wolfgang Denk]

Dear Vikrant,

in message <3D9FDCA910DD4445896A0BE5ECF009D45098CF at bla.satyam.com> you wrote:
>
>  I am trying to port the EP8248 Linux image (which works perfectly on the
> EP8248 board) on 
>  the VPN board (In house board) which is mpc8248 based board.

Please use some more appropriate mailing  list  then.  I  think  this
message is off topic on uclinux-dev.

>  2. The memory map of EP8248 board (REFERENCE BOARD) is:
...
>  SDRAM                    16MByte                      0000_0000--07FF_FFFF
...
> 3. The memory map of the VPN Board (MY BOARD) is as follows:
...
>  SDRAM                    32MByte                      0000_0000 --

Are you sure that your SDRAM is initialized correctly?

>  By putting some Printk's I had cheacked that control is reaching to the
> function mapin_ram(void) in file arch/ppc/mm/pgtable.c Here it is supposed
> to map the 32 MB of virtual memory to the Physical memory.

Ummmm... 32 MB of virtual memory??? I think you mixed this up.

>  The control does not leave the for loop in which the memory mapping takes
> place.

Probably because your RAM is not working.

>  1.Is all this information sufficient to help you understand and pin 

No. Did you VERIFY that your basic memory setup is working in U-Boot?
Can you really access all 32 MB of RAM in U-Boot? Or  maybe  you  can
access just 16 MB, and the second half is mirrored?

>  3. In Reference board (EP8248, RAM size is 16MB) the PAGESIZE is defined as
> 4K, where as in our Board RAM Size is 32 MB. By putting Printk statement in
> the Pagefault function, I Came to know that the control is coming to this
> function and hence pagefault is occurring.Do I need to change the PAGESIZE
> to 8K

Don't even dream of changing things you don't understand. [Short aswer: no.]

>  Any pointers, ideas, comments would be of great help. i would be more 
>  than glad to provide you with any further information required to 
>  debug the problem.

Go read the FAQ. See especially
http://www.denx.de/twiki/bin/view/DULG/UBootCrashAfterRelocation
[Yes, this does apply to your problem.]

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
Remember, there's a big difference between kneeling down and  bending
over.                                                   - Frank Zappa