gpu: nvgpu: Remove force coherency

Remove the code that set default aperture mask as coherent.
MSS nvlink is set for force snoop, so default aperture mask is set as
non-coherent.

Bug 200473147
Bug 3057980

Change-Id: Ia8f826b8414826d2642f9c35c14ffba1cd0b9353
Signed-off-by: Vinod G <vinodg@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2011966
Signed-off-by: Debarshi Dutta <ddutta@nvidia.com>
(cherry-picked from aec64d8f8bcda4a5270a16032005c7b5d1742656
in dev-main)
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvgpu/+/2387271
Reviewed-by: automaticguardword <automaticguardword@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Alex Waterman <alexw@nvidia.com>
Reviewed-by: Bibek Basu <bbasu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: Aayush Rajoria <arajoria@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 0 insertions, 8 deletions

diff --git a/drivers/gpu/nvgpu/common/mm/gmmu.c b/drivers/gpu/nvgpu/common/mm/gmmu.c
index a5790e3a..ee160ae2 100644
--- a/drivers/gpu/nvgpu/common/mm/gmmu.c
+++ b/drivers/gpu/nvgpu/common/mm/gmmu.c
@@ -84,14 +84,6 @@ static u64 __nvgpu_gmmu_map(struct vm_gk20a *vm,
         }
 
         /*
-         * If the GPU is IO coherent and the DMA API is giving us IO coherent
-         * CPU mappings then we gotta make sure we use the IO coherent aperture.
-         */
-        if (nvgpu_is_enabled(g, NVGPU_USE_COHERENT_SYSMEM)) {
-                flags |= NVGPU_VM_MAP_IO_COHERENT;
-        }
-
-        /*
          * Later on, when we free this nvgpu_mem's GPU mapping, we are going to
          * potentially have to free the GPU VA space. If the address passed in
          * is non-zero then this API is not expected to manage the VA space and