what is atags pointer?

[jag]

I am giving below the place where arm-linux starts booting
(from the linux cross reference page:
http://lxr.linux.no/linux/arch/arm/boot/compressed/head.S)

Here in the booting part it mentions of an atag pointer. I could not
see what it is? I googled for it but got no satisfactory results.

start:
115 .type start,#function
116 .rept 8
117 mov r0, r0
118 .endr
119
120 b 1f
121 .word 0x016f2818 @ Magic numbers to
help the loader
122 .word start @ absolute load/
run zImage address
123 .word _edata @ zImage end
address
1241: mov r7, r1 @ save
architecture ID
125 mov r8, r2 @ save atags
pointer

The arm linux boot sequence, explained elsewhere (http://
gicl.cs.drexel.edu/people/sevy/linux/ARM_Linux_boot_sequence.html)
also mentions about the same.

Can someone throw some light on what atags pointer might be, for me?

Thanks in advance.

--
Jag.

[sk....@yahoo.com]

Its the list of parameters passed from the bootloader to the kernel.
These atag_list is a predefined structure which a bootloader can fill
and place at a location in RAM, whose address is passed to kernel
startup as a parameter. Typical things that can be passed are MAC
address of the box, initrd info etc.,

Thanks
Syed