DragonFlyBSD Implements Part Of Linux's IRQ Subsystem, Improves DRM Driver Portability

DragonFlyBSD has implemented a portion of the Linux IRQ subsystem within its kernel.

The purpose of implementing some Linux IRQ subsystem functionality within this BSD kernel is to improve the portability of the Linux DRM (Direct Rendering Manager) driver code.

For years now DragonFlyBSD and many other BSDs have been continually porting the latest Intel/Radeon DRM driver code from the upstream Linux kernel over to their kernels. Over time, more of the Linux interfaces have been added or other compatibility interfaces to ease the process. With DragonFly now sporting some Linux IRQ interfaces, this will allow for reusing more DRM driver code "as-is" from Linux.

This Linux IRQ addition to DragonFly was merged this morning.

Currently the DragonFlyBSD kernel implements Intel and Radeon DRM support from around Linux ~4.8 but with some additions like for Intel Coffeelake graphics support. This latest DragonFlyBSD DRM driver work will be present for the DragonFlyBSD 5.4 release.