An anonymous reader writes
"An AMD engineer has inadvertently revealed that their Windows Embedded graphics driver is ported from the open-source Linux driver. AMD China last year began porting the open-source Radeon Linux kernel driver to Windows Embedded Compact 7, rather than using their Windows Catalyst driver. The resulting WEC7 driver for Radeon GPUs is proprietary, but that's allowed per the MIT license that the ATI-AMD Linux driver code is provided under."