[U-Boot] "Embedding" default script with uboot image

Zatkovský Dušan msk.conf at gmail.com
Fri Oct 2 11:55:03 CEST 2015


Hi,

thx for answer.

My colleague found a way that he:

- converts txt script to u-boot form (by mkimage)
- converts uboot script to .o object ($(OBJCOPY) -I binary -O 
elf32-littlearm -B arm --rename-section .data=.rodata   boot_script 
boot_script.o)
- then:
     extern unsigned char _binary_boot_script_start;
     setenv_hex("boot_script_addr", (ulong)&_binary_boot_script_start);
     run_command_list("source ${boot_script_addr}", -1, 0);

Seems it works OK. Thx you and also him :D

bye

--
Dusan

Dňa 2. 10. 2015 o 9:35 Przemyslaw Marczak napísal(a):
> Hi,
>
> On 09/30/2015 10:06 AM, Zatkovský Dušan wrote:
>> Really nobody?
>>
>> -- 
>> Dusan
>>
>> Dňa 22. 9. 2015 o 14:20 Zatkovský Dušan napísal(a):
>>> Hi all,
>>>
>>> Excuse my question if it was solved somewhere in forum, but I didn't
>>> found an answer yet (maybe I can't find the right keywords).
>>>
>>> I am building the uboot with yocto for imx6 board. I have started with
>>> some freescale defaults,
>>> edited environment for my needs, saved environment etc ... Now I want
>>> to create a custom
>>> "default" boot script, that will do some "heurestics", such as "look
>>> if usb stick is present, then boot from it, else boot from emmc, 
>>> etc...".
>>> Currently I am storing that script on first partition on emmc and
>>> loading it with ext2load.
>>>
>>> But it has drawbacks:
>>> - user should delete that file -> brick
>>> - user should broke entire filesystem -> brick
>>>
>>> I want this script to be "embedded" somehow with uboot image (which is
>>> placed outside partition table on device), but I didn't found any doc
>>> how to do that.
>>> Currently I use CONFIG_EXTRA_ENV_SETTINGS for some basic stuffbut it
>>> is unmaintainable for bigger scripts.
>>>
>>> Any suggestions?
>>>
>>> Thank you.
>>> -- 
>>> Dusan
>>>
>>
>> _______________________________________________
>> U-Boot mailing list
>> U-Boot at lists.denx.de
>> http://lists.denx.de/mailman/listinfo/u-boot
>
> The ELCE is coming, so probably people are busy.
>
> Please check those few suggestions, which can help you:
> - you can "cat" the binaries of U-Boot and your script into one binary
> - you can get the address of your script in the code with few lines:
>
> unsigned long *ptr = (unsigned long *)&_end; - start address of your DTB
>
> ptr += fdt_totalsize(ptr) >> 2; - start address of your script
>
> - you can add some header with "magic code" before your script binary
>
> - check the size limit of your u-boot binary, because your script can 
> be broken if the output binary exceeds the size, which can be loaded 
> to RAM by SPL.
>
> - also check if your bigger binary will not overwrite something on the 
> flash layout
>
> - to execute the script at every boot, you can modify same late 
> function, like autoboot_command in common/autoboot.c ?
>
> - so at this point, you can check your script's magic code - if added
>
> - run script with:
>
> char cmd[64];
>
> sprintf(cmd, "source %p", ptr);
> run_command(cmd, 0);
>
> If you add some logic for checking if the script is valid (e.g. header 
> with size and crc ?), then I think you can be sure, that it will work.
>
> Best regards,



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