[U-Boot-Users] How to reduce the size of u-boot image file

[Wolfgang Denk]

Frank,

in message <BAY2-F84Hoouifm0Sx700057af6 at hotmail.com> you wrote:
> 
> 1. Because of the size of the flash memory constraint, I need to strip the 
> u-boot to its minimum size. Right now by executing "make all" in the u-boot 
> directory, I got a image file u-boot at around 700K-800K. It's too big for 

You must be joking. I haven't seen any configuration yet which exceeds 256 kB.

Did you by any chance look at the ELF file  which  includes  all  the
hewaders, symbol tables, debug informnation etc.?

Forget about this one. How big is your u-boot.bin file?

> my target. So I am thinking about getting rid of some functionalities which 
> u-boot provides. I do need u-boot to initialize my hardware. But after that, 
> I only need to use tftp to get the linux image, decompress the image, put 
> the decompressed image in RAM and jump to the linux entry point to let the 
> linux take over the control. Is there any FAQ or manual explaining how to 
> strip down the u-boot size?

Yes. The README explains how to enable or disable commands or command groups.

> 2. Since my flash memory address starts from 0xFFC00020 instead of 

Please check again. I think it is IMPOSSIBLE to have  a  flash  start
address of 0xFFC00020. I guess you mean 0xFFC00000 ?

> 0xFFF80000, so I changed the TEXT_BASE in board/walnut405/config.mk to 
> 0xFFC00020. When I use "make u-boot", everything is fine. But if I use "make 
> u-boot.bin", it ends up with a u-boot.bin more than 4MB. I think I didn't 

This is normal. U-Boot includes  the  jump  statement  at  the  reset
vector, 0xFFFFFFFC.

> get the TEXT_BASE set correctly. Isn't TEXT_BASE the start point of the 
> flash? If it isn't, what does TEXT_BASE mean? And where to indicate the 

Yes, it is. And if you put U-Boot at the start of the flash, and  the
reset  vector  is  in  the  last word, then the U-Boot image needs to
cover your whole 4 MB of flash memory.

You just get what you ask for.


Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd at denx.de
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