[clug] Raspberry Pi WLAN issues

Bob Edwards Robert.Edwards at anu.edu.au
Tue May 27 21:32:38 MDT 2014


On 28/05/14 13:23, Chris Smart wrote:
> On 28/05/14 13:13, Jeff Stiff wrote:
>> Thanks Chris.
>> Hadn't looked that closely at the boot chain yet to discover that. Had just
>> been looking at the OS which seemed/s fairly standard.
>>
>> One question, why does the boot loader then make the machine useless for
>> your use case, what were you wanting to use it for?
>
> I wanted to build my own custom system on it. You can't run regular
> distros on it or roll your own (although Arch does have an image which
> includes the signed bootloaders) - you can only use hardkernel's OS images.
>
> Hardkernel did say that they would sign your bootloader though, if you
> submit it to them and give them a few days.
>
> However I was looking for a completely open boot process to build some
> custom cool stuff, so to that end it was no good for me. Maybe with more
> pressure on Samsung that will change.
>
> However, if you're happy to run the hardkernel images it's fine - the
> android works quote well (although I'd like to build that myself). If
> you want a regular distro, Arch seems the best, but be prepared to deal
> with GPU driver issues regardless.
>
> Some info on boot sequence here:
> http://dev.odroid.com/projects/4412boot
>
> Quoting, "Upon power on the board/tablet will search for the boot media.
> It will perform the following:
>
>      1) iROM (Code inside the SoC) will attempt to read the boot media at
> the first 512 bytes of it. On those first 512 bytes fwbl1 should exist.
>      2) fwbl1 will load bl2 (SPL) that is part of the U-Boot.
>      3) bl2 will load U-boot
>      4) U-Boot will do whats left, such as handle TrustZone, load kernel
> image and Ramdisk if setted."
>
> -c
>

I haven't had time to look into it closely, but I think the Allwinner
SoCs (such as that used on pcDuino) don't have signed bootloaders and
run "standard" U-Boots. But I could be wrong. The GPU probably still
needs a binary blob, if you want to use that.

Thanks for raising the issue. RaspPi has similar issues, or used to
at some point. Its philosophical, but I completely agree with your
stance.

Bob Edwards.


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