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

[himba <himba@siol.net>]

Christian Kapeller wrote:
> ## 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. 
> 

Couple of weeks ago played a little with ATAGs and I discovered that 
in order to see printk()s I added in setup.c I had to _always_ do make 
clean; make uImage... Maybe thats where your other ATAGs are - passed 
in, just not printed.

> Also when using 2.4.19-rmk7-pxa2 i get that bootup line:
> 
> ignoring unrecognised tag 0x00000000
> 
> 
I think I got this one too, it is ATAG_NONE, just marking the end of 
list, nothing else

> 
> 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.
> 
This happened to me also when I didn't compile uboot with 
CONFIG_CMDLINE_TAG option.
Also are you telling the kernel where to find BOOT_PARAMS?


hth,
himba