On 10/04/17 09:56 AM, Michel Dänzer wrote: > On 08/04/17 05:15 AM, Felix Kuehling wrote: >> Advertise CIK PCI IDs only when they are not supported by amdgpu. >> Use the CONFIG_DRM_AMDGPU_CIK to check so that a single option in >> the kernel config keeps both drivers in sync. >> >> This is the simplest possible change. A more complete solution >> may want to conditionally disable more CIK-specific code in the >> Radeon driver. >> >> v2: Add CONFIG_DRM_RADEON_FORCE_CIK option >> >> Signed-off-by: Felix Kuehling <Felix.Kuehling at amd.com> > > I don't think this is good enough a solution. To elaborate, my main objection is that people who still want to be able to use the radeon driver for CIK/SI GPUs with CONFIG_DRM_AMDGPU_CIK enabled have to enable the new CONFIG_DRM_RADEON_FORCE_CIK/SI option, and then they're merely back to square one, in the current situation where it's not clearly defined which driver will end up being used for such GPUs. > CONFIG_DRM_AMDGPU_CIK/SI would then simply define which driver gets to > drive CIK/SI GPUs by default. To avoid the above, I'd say this should be the first step: Make CONFIG_DRM_AMDGPU_CIK/SI define which driver will register for CIK/SI GPUs by default. This does require some way to override it at runtime, though. A simple initial solution for that might be "force_cik"/"force_si" module parameters in both drivers. Setting force_cik/si=1/0 would make the driver register for / not register for CIK/SI GPUs. -- Earthling Michel Dänzer | http://www.amd.com Libre software enthusiast | Mesa and X developer
