Re: Booting Linux using a PlanetCore BootLoader

[annamaya <annamaya@yahoo.com>]

I loaded a zImage into address 0x100000 in RAM and
verified that this was indeed an ELF file. I then said
"go 0x100040" which would start executing the code
after skipping the 64 bytes of ELF header. But this is
what I see happen. 

BDI>info
    Target CPU        : MPC8280/8220/5200 (Zeppo)
    Target state      : debug mode
    Debug entry cause : <reserved 0>
    Current PC        : 0x00100040
    Current CR        : 0x20004022
    Current MSR       : 0x00000000
    Current LR        : 0xfff0531c

It looks like address 0x0 is reserved for some weird
reason. When I do a dump of the 0x0 area, it looks
like there is copy of the planetcore bootloader here
since I see some text indicating that. If I dont have
the BDI hooked up, I see an immediate reboot of the
device, consistant with executing the bootloader at
0x0. 

Any inputs on why this is happenning? I just
understand the PlanetCore bootloader very well.

--- Dan Malek <dan@embeddededge.com> wrote:

> 
> On Oct 11, 2004, at 12:04 PM, annamaya wrote:
> 
> > I am trying to boot a linux kernel using a
> PlanetCore
> > BootLoader on an embedded planet board. I am used
> to
> > always using U-Boot for my Kernel booting needs. I
> am
> > not sure how to get this going on a PlanetCore
> boot
> > loader.
> 
> You need to build a zImage so you get the simple
> bootloader that will read the information from the
> EEPROM
> and format the board structure.
> 
> Load the zImage file as a binary.  It has a 64K ELF
> header
> on it, so you can either use 'dd' to strip that
> before the
> download or add 64K to the load address to use as
> the
> start address.  The start address is the first
> instruction of
> the image (or +64K if you didn't remove the ELF
> header).
> 
> 
> 	-- Dan
> 
> 



		
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