Custom Build

General programming chat and advice for beginners

5 posts
by alberich2k5 » Wed Jun 27, 2012 9:54 am
Hello!

I just got my raspberry pi. After trying the available distros, I want to build my tiny custom firmware. (not a full distro). I downloaded everything from github, and I have a doublt about the boot directory.

Why there are so many different .elf files?

About the mkimg python scripts, is it necesary to use the first32k.bin file? I supose it contains the boot loader, or only needed firmware?

Thanks!!
Alberich
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by DexOS » Wed Jun 27, 2012 1:59 pm
There are two modes of boot for the R-PI, depending what you set in the config.txt (or if you do not have a config.txt).
One is it boots from offset 0, in that case you will need first32k.bin file (it just jumps to offset 0x8000).

Two is its loaded and boots from 0x8000, in which case you do not need first32k.bin file

You will need to check up on the latest setting for this as, it could of changed.

See here for more info
viewtopic.php?p=95414#p95414
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by alberich2k5 » Wed Jun 27, 2012 5:22 pm
Thanks Dexos for the reply.

I read the hole thread you said :)

About the loader, the only options I have is to use the ones provided in the https://github.com/raspberrypi/firmware? I mean, no sources?

The firmaware file format, is the tipical one:
cat loader kernel rootfs > firm?

Or do i need to do something? (I tried this way, and it didn't worked for me).

Thanks!!!
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by alberich2k5 » Thu Jun 28, 2012 7:12 pm
Sorry to insist,

But about the firmware file to load in the SD, does it need any special format?
Are there any sources available for the boot loader?

thanks!
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by DexOS » Fri Jun 29, 2012 11:54 am
alberich2k5 wrote:Sorry to insist,

But about the firmware file to load in the SD, does it need any special format?
Are there any sources available for the boot loader?

thanks!

Sorry mist your post, no theres no source, the files with .bin are binary files and the .elf are "executable and linkable format".
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