Driver for Raspberry Pi 4 PCI-express controller

[Klaus Küchemann]

> Am 28.05.2020 um 20:45 schrieb Robert Crowston <crowston at protonmail.com>:
> 
> I did test on a pi4 with the latest USB firmware. A keyboard functioned okay without me doing anything special.
> 

O.K., after cleaning and completely renewing my msdos-partition on the uSD again I could not reproduce all the crashes from my last tests
( as long as I don’t touch the msdos-partition with any file-changes).
So once beeing in a clean setup: keyboard/mouse works, HDMI works, xorg works, 
Mounting an SSD-drive and copying a file(140MB) to it worked.detaching/reattaching all devices/hubs didn`t produce failures.

When I touch the msdos-partition in any way(e.g. overwriting a file), the problems come back 
And it’s unclear to me why it specially affects the pcie/usb-functionality and not other functionality…. but it is possible that my uSD is simply damaged and needs reformatting ..

Assuming that users normally  don't change the msdos partition, and we could e.g. add 
invisibility the overlay-folder and other files , I would say:
The driver is ready for review at Phabricator - and then the experts can give their mustage ..

although it would be better if we had more pre-testers (anyone here?) : I see no heavyweight reason to not give the patch for review on phab.... 

and thanks Robert for writing  the driver