[U-Boot-Users] Porting U-Boot to an ARM920T-Based Board.

[U-Boot-Users] Porting U-Boot to an ARM920T-Based Board.

[Rodel Miguel]

Hi,

I would like to get some help to port u-boot on a new hardware (the
hardware is still under heavy development).

I have listed the following issues which I've encountered while
reading the README and browsing the source tree.

1.  My board has an ARM920T core.  Instinctively, I would choose a
"template" board support subdirectory that has the same core.  If my
platform is very different from the template,  can I just choose the
board that fits my needs (e.g. UART, FLASH, MEMORY MAP, etc.) and just
re-configure the core?  If this is possible, how do I do this?

2.  My UART port is 16550 compliant.  The ARM920T core (cpu/arm920T/)
is using a serial.c that is compliant to S3C24XX.  Can I just simply
overwrite cpu/arm920t/serial.c with 16550 compliant serial.c?

3.  Can somebody please tell me the files that are most-likely to
change when porting u-boot to a new platform?  Currently I am
modifying the following:

     board/myboard /* copied from board smdk2410 */
          - What should be placed here?  Initialization routines? 
What is the "minimal" requirement for this subdirectory?

     Makefile - to make our board noticable to the main kernel tree

     include/configs/myboard.h

4. Are there other important files to modify in order to build the
proper u-boot image?

Please advise on the stated issues.  Thank you very much.

Regards,
Rodel Miguel

[U-Boot-Users] Porting U-Boot to an ARM920T-Based Board.

[Wolfgang Denk]

Dear Rodel,

in message <515b5ffa04100508563e7d6b6f@mail.gmail.com> you wrote:
> 
> 1.  My board has an ARM920T core.  Instinctively, I would choose a
> "template" board support subdirectory that has the same core.  If my
> platform is very different from the template,  can I just choose the

Please don't ask "can I". Of course you can. _Anything_ can be  done.
The  question  is  if it makes sense to do it, and how much effort it
needs.

> board that fits my needs (e.g. UART, FLASH, MEMORY MAP, etc.) and just
> re-configure the core?  If this is possible, how do I do this?

Yes, you can chose a similar board and re-use it's code. This is what
U-Boot is all about.

> 2.  My UART port is 16550 compliant.  The ARM920T core (cpu/arm920T/)
> is using a serial.c that is compliant to S3C24XX.  Can I just simply
> overwrite cpu/arm920t/serial.c with 16550 compliant serial.c?

No, you cannot. You will use the existing  code  in  drivers/serial.c
instead.

> 3.  Can somebody please tell me the files that are most-likely to
> change when porting u-boot to a new platform?  Currently I am

Please read the README.

>      board/myboard /* copied from board smdk2410 */
>           - What should be placed here?  Initialization routines? 
> What is the "minimal" requirement for this subdirectory?

This depends on your requirements. The minimum is the  initialization
needed to get your board started.

> 4. Are there other important files to modify in order to build the
> proper u-boot image?

Maybe, but unlikely.


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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