gpu: nvgpu: Check for all sysmem apertures in GMMU

Allow a potential IOMMU'ed GMMU mapping for all SYSMEM buffers
inlcuding coherent sysmem. Typically this won't actually happen
since IO coherent mappings will also often be accessed over
NVLINK which is physically addressed.

Also update the comments surrounding this code to take into
account the new NVLINK nuances. Since NVLINK buffers are
directly mapped even when the IOMMU is enabled this is very
deserving of a comment explaining what's going on.

Lastly add some simple functions for checking if an nvgpu_mem
(or a particular aperture field) is a sysmem aperture. Currently
this includes SYSMEM and SYSMEM_COH.

JIRA EVLR-2333

Change-Id: I992d3c25d433778eaad9eef338aa5aa42afe597e
Signed-off-by: Alex Waterman <alexw@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1665185
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/include/nvgpu/nvgpu_mem.h b/drivers/gpu/nvgpu/include/nvgpu/nvgpu_mem.h
index 302f7287..c5e3e752 100644
--- a/drivers/gpu/nvgpu/include/nvgpu/nvgpu_mem.h
+++ b/drivers/gpu/nvgpu/include/nvgpu/nvgpu_mem.h
@@ -217,6 +217,9 @@ static inline const char *nvgpu_aperture_str(struct gk20a *g,
         return "UNKNOWN";
 }
 
+bool nvgpu_aperture_is_sysmem(enum nvgpu_aperture ap);
+bool nvgpu_mem_is_sysmem(struct nvgpu_mem *mem);
+
 /*
  * Returns true if the passed nvgpu_mem has been allocated (i.e it's valid for
  * subsequent use).