Your ROOT_URL in app.ini is https://src.whiteboxsystems.nl/ but you are visiting http://src.whiteboxsystems.nl/Whitebox/u-boot/src/commit/7f0cfe478bd817d2bb373522222cf06630fea3cd/drivers/twserial You should set ROOT_URL correctly, otherwise the web may not work correctly.
upstream u-boot with additional patches for our devices/boards: https://lists.denx.de/pipermail/u-boot/2017-March/282789.html (AXP crashes) ; Gbit ethernet patch for some LIME2 revisions ; with SPI flash support
 
 
 
 
 
 
u-boot/drivers/twserial
..
Makefile
soft_tws.c