[yocto] [meta-raspberry] Raspberry Pi 3

[Trevor Woerner]

On Thu 2016-03-31 @ 09:36:16 AM, Khem Raj wrote:
> 
> > On Mar 31, 2016, at 8:26 AM, Trevor Woerner <twoerner at gmail.com> wrote:
> > 
> > On Fri 2016-03-18 @ 10:15:39 AM, David Weisgerber wrote:
> >> Hi,
> >> did anyone succeed in building an image that runs on Raspberry Pi 3? I set my
> >> conf/local.conf to
> >> 
> >> MACHINE ??= "raspberrypi3"
> >> GPU_MEM = "128"
> >> DISABLE_OVERSCAN = "1"
> >> 
> >> and built rpi-basic-image but when booting the Pi 3 up I only see 4
> >> raspberries in the top right but nothing else happens. The image works
> >> perfectly on a Pi 2 though.
> > 
> > I'm able to get a raspi3 image running on my Raspberry Pi 3, but my console is
> > messed up. Everything works fine via the usb+hdmi ports, but plugging a
> > console cable into the GPIO header is messed up.
> > 
> > It looks like what happens when the baud rate is set incorrectly, but I've
> > tried every baud rate in my terminal emulator and it all looks the same
> > (messed up).
> > 
> > Anyone got their console working? The same cable/setup works fine on the
> > raspi2 (ttyAMA0) but doesn't work on my raspi3 (ttyS0).
> 
> did you try
> 
> https://www.mail-archive.com/yocto@yoctoproject.org/msg28476.html

As far as I can tell there are two raspberry pi OE layers which include this
commit:

1. git://git.yoctoproject.org/meta-raspberrypi::master
2. https://github.com/kraj/meta-raspberrypi.git::kraj/master

Building two fresh, from-scratch Poky images using the latest up-to-date
sources for:

	meta-openembedded/meta-oe
	openembedded-core/meta
	meta-poky/meta-poky

and swapping in the two raspberrypi layers (one at a time) I get:

 - Using 1 (the official layer from Andrei) I get an image that boots but the
   console remains messed up (as before).

 - Using 2 (the layer from Khem) I get an image that flashes the rainbow
   pattern on the HDMI monitor, shows the 4 berries, then stops. Nothing else
   happens, no messages on the console.

In both cases I'm building core-image-full-cmdline, and the only tweak in
local.conf is:

	ENABLE_SPI_BUS = "1"

As far as I can tell, the only difference between the two raspberry pi layers
is the kernel. Andrei's uses 4.1 and Khem is using 4.4:

	$ git show-branch kraj/master origin/master 
	* [kraj/master] userland: Fix tearing effect seen with wayland compositors
	 ! [origin/master] userland: Fix tearing effect seen with wayland compositors
	--
	 + [origin/master] userland: Fix tearing effect seen with wayland compositors
	 + [origin/master^] firmware: Update to 20160326
	*  [kraj/master] userland: Fix tearing effect seen with wayland compositors
	*  [kraj/master^] firmware: Update to 20160326
	*  [kraj/master~2] linux-raspberrypi: Make 4.4 default kernel
	*+ [origin/master~2] userland: Implement dispmanx_wrap_buffer

I'll try core-image-minimal and no SPI flag. Unless someone else has
better-sounding ideas?

Best regards,
	Trevor