[U-Boot-Users] Re: Flawed ATAG passing

Christian Kapeller e0225408 at student.tuwien.ac.at
Mon Aug 2 10:57:37 CEST 2004

## setup_start_tag
## setup_memory_tags start a0000000 size:04000000
## setup_commandling_tag size:0000001c line: root=/dev/ram0 init=/linuxrc
## setup_initrd_args start:00200040, end:00466a68
## setup_end_tag

>> Machine: Intel DBPXA250 Development Platform (aka Lubbock)
>> parse_tags number of tags: 5
>> parsing tag: 0x54410001
>> parse_tag: tag 0x54410001 
>> parse_tag_core
>> parsing tag: 0x54410002
>> parse_tag: tag 0x54410002 
>> parse_tag_mem32 start 0xa0000000 size 0x01000000
>So your bootloader is passing fine the tags to kernel.

That's right. You can also see, that only the ATAG_CORE (0x54410001) and
and ATAG_MEM (0x5441002) are parsed. There should be another 3 tags. After 
the memtag is processed parsing stops. 

Also when using 2.4.19-rmk7-pxa2 i get that bootup line:

ignoring unrecognised tag 0x00000000

## setup_commandling_tag size:0000001c line: root=/dev/ram0 init=/linuxrc
>> Kernel command line: root=/dev/ram console=ttyS0,115200

I experienced also the phenomenon, that the kernel commandline that is 
set through the bootargs variable are not acepted/parsed. Only the default
commandline is used.

>Your kernel fails to mount the ramdisk, since you have RAMDISK driver 
>etc, then the next most likely reason is you are missing the filesystem 
>support in your kernel.  For exampel if your ramdisk in in ext2 format 
>then make sure your kernel has ext2 support compiled in (not as a module).

I think i configured the kernel correctly. Ramdisk support/initrd support. 
The initial Ramdisksize is greater than the size of my initrd. ext2 is the
used filesystem. I also applied the ramdisk relocation patch. It didn't
solve the problem.

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