gpu: nvgpu: Remove gk20a sparse texture & PTE freeing

Remove support for gk20a sparse textures. We're using implementation
from user space, so gk20a code is never invoked.

Also removes ref_cnt for PTEs, so we never free PTEs when unmapping
pages, but only at VM delete time.

Change-Id: I04d7d43d9bff23ee46fd0570ad189faece35dd14
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/663294

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index 419b8675..2b8276e3 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -1786,9 +1786,11 @@ int gk20a_init_gpu_characteristics(struct gk20a *g)
                 gpu->available_big_page_sizes |= g->ops.mm.get_big_page_sizes();
 
         gpu->flags = NVGPU_GPU_FLAGS_SUPPORT_PARTIAL_MAPPINGS
-                | NVGPU_GPU_FLAGS_SUPPORT_SPARSE_ALLOCS
                 | NVGPU_GPU_FLAGS_SUPPORT_SYNC_FENCE_FDS;
 
+        if (g->ops.mm.set_sparse)
+                gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_SPARSE_ALLOCS;
+
         if (IS_ENABLED(CONFIG_TEGRA_GK20A) &&
             gk20a_platform_has_syncpoints(g->dev))
                 gpu->flags |= NVGPU_GPU_FLAGS_HAS_SYNCPOINTS;