[QUESTION] sh_mem_bases: amdkfd vs amdgpu

[robert.dazi at yahoo.com]

Hi,

There is an interesting feature divergence between amdgpu and amdkfd concerning the shared/private apertures. I restricted my analysis to gfx9, it may differ with other gfx.

In amdgpu, the pair of aperture start addresses is defined the following way (in gmc_v9_0.c):

* shared_aperture_start = 0x2000000000000000ULL
* private_aperture_start = 0x1000000000000000ULL 

In amdkfd, the pair is reversed (cf kfd_flat_memory.c and kfd_device_queue_manager_v9.c):

* lds_base (ie shared_aperture_start) = (0x1UL) << 48
* scratch_base (ie private_aperture_start) = (0x2UL) << 48

Is there any reason why those two definitions diverge ?

Thanks,

RD