[yocto] raspberrypi3-64 target not booting

[Paul Barker]

On Mon, Sep 4, 2017 at 9:31 PM, Paul Barker <pbarker at toganlabs.com> wrote:
> On Fri, Aug 25, 2017 at 6:27 PM, Khem Raj <raj.khem at gmail.com> wrote:
>> On Fri, Aug 25, 2017 at 10:14 AM, Bill Jenkins <bill at korgrd.com> wrote:
>>>
>>> On Aug 25, 2017, at 9:42 AM, Khem Raj <raj.khem at gmail.com> wrote:
>>>
>>>
>>> On Fri, Aug 25, 2017 at 9:39 AM Bill Jenkins <bill at korgrd.com> wrote:
>>>>
>>>> I am trying to just get the simple 64-bit rpi-basic-image to work, but the
>>>> Raspberry Pi 3 seems to hang with the rainbow screen at startup.
>>>
>>>
>>> Can you plugin a serial cable and see if that worked or try to add ssh
>>> daemon on target and try to ssh into pi
>>>>
>>>>
>>>
>>> That was a good call. I can login with the ssh daemon, so it does
>>> successfully boot. I just
>>> cannot access it from the HDMI port. (I do not have the hardware for a
>>> serial connection
>>> at the moment)
>>>
>>> Any ideas on how to get the HDMI port to function the same way as it does
>>> for the
>>> 32-bit case?
>>>
>>
>> Readding the mailing list.
>>
>> what you have is exactly what I had when I submitted the port to
>> meta-raspberrypi. Haven;t had a chance to revisit it. but this could
>> be related to device tree files we are using here. I have had reports
>> from other devs of having been able to boot into graphics using older
>> kernels but I never got
>> that far myself.
>
> I'm seeing the same issue on builds from both pyro and master
> branches. I've confirmed this isn't a HW issue by trying out an
> OpenSUSE Leap 42.2 64-bit build for Raspberry Pi 3.
>
> Khem, are you saying this is the current expected state of Raspberry
> Pi 3 64-bit support? If so I'd really like us to document this in the
> readme and open a bug so we don't lose track of it.
>

So, here's where I'm up to:

I've proposed a bunch of clean-ups and improvements here:
https://github.com/agherzan/meta-raspberrypi/pull/120. The main thing
for this discussion is that I have u-boot working on raspberrypi3-64
and it can boot Linux.

When not using u-boot, I get the colour palette on the screen but I
can ssh into the card after a short delay and confirm that everything
except graphical output seems to be working.

When using u-boot, I get u-boot output on my screen. It gets stuck at
"Starting kernel ..." which I thought was related to another issue but
it's not. Linux does come up and I can ssh in as before, it just
doesn't have any graphical output. The u-boot output is left on the
screen.

So I did a clean checkout of rpi-4.9.y from
https://github.com/raspberrypi/linux and built using the exact
settings in bcmrpi3_defconfig (no config changes) and the
gcc-aarch64-linux-gnu package in Ubuntu 16.04:

    export ARCH=arm64
    export CROSS_COMPILE=aarch64-linux-gnu-
    make mrproper
    make bcmrpi3_defconfig
    make -j8

I then took arch/arm64/boot/Image and copied it over the top of
kernel8.img in the boot partition of my rpi3-64 image. I now have
working graphical output :)

So I think this is due to either the kernel config changes we make,
the commit hash we use having a bug which is now fixed or a toolchain
issue. Userspace is not involved here.

I'm not going to have much time this weekend to look into this but I
can get back to it next week. If anyone else wants to pick up where
I'm leaving off feel free to!

Thanks,

-- 
Paul Barker
Togán Labs Ltd