Hello - I'd like to start by saying thanks gain to all for the continued work 
on this project!

 
I'm reaching out again for help on my beaglebone + yocto project. I feel like I 
am really close to a functional implementation, but I am now stuck on getting 
my LCD screen to render anything (for reference, I am using one of these - 
https://4dsystems.com.au/4dcape-43). My hunch is that I need to enable the 
device tree overlay for the cape.

 
I've spend a few days poking around, and have a recipe in my yocto project that 
compiles the overlay files from this repo - 
https://github.com/beagleboard/bb.org-overlays. 
<https://github.com/beagleboard/bb.org-overlays.>   At this point, I have a 
bunch of compiled `.dtbo` files both being written to the `DEPLOY_DIR_IMAGE` 
and the boot partition of my wic file which is exciting (my guess is I am 
specifically interested in this one - 
https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/BB-BONE-4D4C-01-00A1.dts)
 
<https://github.com/beagleboard/bb.org-overlays/blob/master/src/arm/BB-BONE-4D4C-01-00A1.dts).>
 . 

 
The current hurdle I am facing is that when I attempt to apply the overlay from 
my u-boot script - running `fdt apply ...` prints the following error to the 
console:

 
```

failed on fdt_overlay_apply(): FDT_ERR_BADSTRUCTURE
base fdt does did not have a /__symbols__ node

make sure you've compiled with -@

```

 
That error seems pretty clear but I'm still seeing it after subsequently adding 
`KERNEL_DTB_OVERLAY_SUPPORT = "1"` to a bbappend file for `linux-ti-staging_%`. 
I have dumped the contents of my fdt file (am335x-boneblack.dtb) using 
`fdtdump` and it looks like there is a `__symbols__` entry. This was also the 
case when manually running `fdt print` from a u-boot prompt and saving the 
output to a logfile through `screen`.

 
I've uploaded the full device tree output from `fdt print` to this gist: 
https://gist.github.com/dadleyy/7926873ab60e9c9b5b5b02cb44e1e70b 
<https://gist.github.com/dadleyy/7926873ab60e9c9b5b5b02cb44e1e70b> 

 
I've also been reading the u-boot docs here - 
https://u-boot.readthedocs.io/en/latest/usage/fdt_overlays.html 
<https://u-boot.readthedocs.io/en/latest/usage/fdt_overlays.html> 

and this blog post from 2018 - 
https://irq5.io/2018/07/24/boot-time-device-tree-overlays-with-u-boot/

 
My guess is that I am doing something wrong with the length and/or address of 
the fdt file or the overlay I am trying to use. I would be happy to provide any 
additional information, and any assistance is really appreciated!

 
Thanks,

- Danny

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