Re: Question - loading and running u-boot from RAM
From: Wolfgang Denk <hidden>
Date: 2004-07-14 21:51:51
In message [ref] you wrote:
I am newbie to this list and linux. Let me start by
You introduce yourself with an off-topic posting. U-Boot related questions do not belong on the linuxppc-dev list. Please post such stuff to u-boot-users instead.
saying that I know that my question is FAQ and I have read the archives. However, I would still like to
You did?
know if some one can outline what needs to be changed (configuration and code) in order to be able to build a u-boot binary that can be loaded into SDRAM and executed from their.
This has been discussed many times on the u-boot-users mailing list. I'm absolutely sure you can find it there in the archives.
1. I am working for a very smal company that can not afford low level debuggers. And therefore, every time
Divide the price for a BDI2000 by your hourly rate. _Especially_ since you are a beginner you will find (probably not now, but later) that it is cheaper to buy the right tools for the job. Not to mention the time-to-market factor.
2. The board I am using has socket for the flash, and socket is flaky. Therefore, when there is a problem, I don't know if it is the socket or the code I changed.
That's one more reason to use a BDI2000 which allows to program the flash in situ (even if soldered on).
But after that I would like to boot my system from flash and tftp my test u-boot image into SDRAM and run it from their. Once I know my code is working, then I can go ahead and burn the new u-boot image into flash.
Exactly this will not happen. The changes you have to make to boot from RAM need to be reverted to boot from flash, and there is zero guarantee that the code will continue to work.
I am using MPC8540 and u-boot 1.1.1. I realize that this is a subject that has been talked about before. However, I believe(as newbie) that if someone can outline this process, it can be big help to developers with less budget and tools to work with.
You are wrong. It doesn't help. If you have a lot of experience and
know exactly what you are doing, you can try something like this, and
it may even be efficient in some situations. But even then (and
especially then) you will want to use the right tools. And without a
lot of experience, well, you will need veerryyyyy much time.
Best regards,
Wolfgang Denk
--
Software Engineering: Embedded and Realtime Systems, Embedded Linux
Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd@denx.de
Let's say the docs present a simplified view of reality... :-)
- Larry Wall in [off-list ref]
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