[BUMP]: Re: Raspberry PI 3 - initial newb - help!

[Da Rock]

Still struggling a bit with u-boot concepts: rpi boots, looks in the mbr 
with fat partition for u-boot. U-boot is not specifically in any address 
as such so it has to actually look for it. So why does ubldr require a 
start address? Which address is it looking for? And how do I find it? 
Until I figure that out I can't compile it can I?

To clarify also, the dtb is configured in the config for u-boot? Then 
u-boot passes that in to ubldr? Or can't FBSD handle that at this stage?

And has anyone tried the display connection onboard at all? Would that 
work better than the hdmi by actually displaying processes occurring 
like the u-boot?


On 10/07/2016 12:18, Da Rock wrote:
> Ok, so I got my hands on a RPi3 knowing that things aren't probably 
> going to work straight off. Never worked with arm before, but trying 
> to move towards the "future" :) rather than keep buying laptops. 
> Haven't had much success with qemu as yet, and so thought hardware 
> might be better and more fulfilling anyway. And they finally came in 
> stock locally as well, so grabbed it while I could.
>
> Booted raspbian straight off to get a handle on what control should 
> look like, and got a nice little system with a rainbow icon in the 
> corner (?). Grabbed the output from dmesg and such and kept a copy on 
> my laptop.
>
> My next research was to try building freebsd for arm/rpi3. Got current 
> (10.x wouldn't do it) and built a distribution for arm64. So far so 
> good - cross compile works fine with clang. (Remember, complete newb 
> with cross compiling, arm, all that - worked on x86 only)
>
> I then looked at the booting process, and u-boot. Sounds like a 
> mindfield.... fun. Also came across crotchet, which as I understand 
> has all this scripted, but for my purposes I need to actually 
> understand the steps rather than have the script do it for me at this 
> stage. So not real helpful at this point - if someone could point out 
> the steps taken would be good.
>
> So I then checked out the 10.3 rpi img from the FreeBSD downloads, and 
> tried booting. NG. All I get is a rainbow test screen. Same with a 
> 11-current version too.
>
> I post this here so I can get some pointers and advice on how to 
> continue in my research and possibly getting my rpi3 to run.
>
> It looks to me that the u-boot is grabbing the wrong address and so 
> not booting the imgs properly.
>
> Question: if the u-boot use loader to boot, then does that mean that 
> once set there is no need to rebuild all as such - a kernel change can 
> be initiated without hiccup? In other words, u-boot and loader stay in 
> place, but nearly all can change around that?
>
> I'm also noting the FDT, and I have the actual dtb file for the rpi3, 
> but how would I use it? Am I right in assuming the file is platform 
> neutral, and so will work for linux and FreeBSD?
>
> Is there any good tutorials on using u-boot and configuring it correctly?
>
> And the main reason why I could never get qemu to work with arm was it 
> kept asking for a kernel file - is that meant to be the u-boot file then?
>
> Cheers
> _______________________________________________
> freebsd-arm at freebsd.org mailing list
> https://lists.freebsd.org/mailman/listinfo/freebsd-arm
> To unsubscribe, send any mail to "freebsd-arm-unsubscribe at freebsd.org"