Choose this option if you want kern

Choose this option if you want kernel modesetting enabled by default.This is a completely new driver. It's only part of the existing drmfor compatibility reasons. It requires an entirely different graphicsstack above it and works very differently from the old drm stack.i.e. don't enable this unless you know what you are doing it maycause issues or bugs compared to the previous userspace driver stack.When kernel modesetting is enabled the IOCTL of radeon/drmdriver are considered as invalid and an error message is printedin the log and they return failure.KMS enabled userspace will use new API to talk with the radeon/drmdriver. The new API provide functions to create/destroy/share/mmapbuffer object which are then managed by the kernel memory manager(here TTM). In order to submit command to the GPU the userspaceprovide a buffer holding the command stream, along this bufferuserspace have to provide a list of buffer object used by thecommand stream. The kernel radeon driver will then place bufferin GPU accessible memory and will update command stream to reflectthe position of the different buffers.The kernel will also perform security check on command streamprovided by the user, we want to catch and forbid any illegal useof the GPU such as DMA into random system memory or into memorynot owned by the process supplying the command stream. This partof the code is still incomplete and this why we propose that patchas a staging driver addition, future security might forbid currentexperimental userspace to run.This code support the following hardware : R1XX,R2XX,R3XX,R4XX,R5XX(radeon up to X1950). Works is underway to provide support for R6XX,R7XX and newer hardware (radeon from HD2XXX to HD4XXX).