[U-Boot-Users] ATAG Parameters

Swapnil Ashok Narkhede S3092131 at student.rmit.edu.au
Fri Nov 11 17:06:45 CET 2005


When U-boot passess control from itself to
kernel it passess some ATAG parameters
which is critical information for the kernel
to boot.
I analysed the U-boot code and the
Kernel code and i have come up with
some interpretation

FOR ARM(arm-pxa)
U-boot defines the params like ATAG_CORE,
Now the definition looks like this
#define ATAG_CORE	0x54410001
#define ATAG_INITRD2	0x54420005

Does 0x54410001, 0x54420005 represent
physical memory address, which are
reserved, as per the Memory Map information
from the Processor data sheets.

In the kernel code i find the same
definition of the above  parameters.

Does this mean U-boot stores some value/info
at 0x54410001, 0x54420005, and since the
kernel code has same definition of the
ATAG parameters(of 0x54410001, 0x54420005)
the kernel can get the value/info stored at
0x54410001, 0x54420005.

PLease let me know if this is the correct
interpretation and if not, then what is the 
correct concept.

Swapnil Narkhede
Mob:- 0432025023
Email:- s3092131 at student.rmit.edu.au
School of Computer Science and Information Technology
RMIT University, Melbourne

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