@kwilczynski No vendors stepped in to provide hardware for testing by Linux maintainers? No surprise...
There is somehow quite a big disconnection between big corporations making millions of products and Linux, and us - people actually developing Linux. Knowing enormous expenses in the marketing of big corporations, one could imagine what it is to donate a few boards to real Linux maintainers, right?
Nope.
I had a similar problem some time ago - till I gave up - with Samsung. I am the maintainer of Samsung SoC in Linux kernel, but all the boards were either purchased by me, donated by a friend in Germany, donated by a friend from Google or donated unofficially by a few good folks from Samsung R&D Poland.
When I asked Samsung Open-source or Samsung LSI (the one making SoCs I maintain) the answer was either silence or "no boards". One more board might now come from Samsung thanks to a project between Linaro and Samsung, but it is an exception.
And that makes me every time very rough in reviewing big-corporations code. Sorry guys, you do not play fair.