gpu: nvgpu: expose deterministic submit support

Add these bits in the gpu characteristics flags:

NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_NO_JOBTRACKING - fast
submits with no in-kernel job tracking are supported.

NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_FULL - deterministic
submits also with job tracking and num_inflight_jobs set are supported.

Either of these may get disabled if the particular channel or submit
still requires features that block these.

Make gk20a_channel_sync_needs_sync_framework() take a gk20a pointer
instead of a channel pointer so that it can be called without a channel.
It does not need any per-channel data.

Bug 200291300

Change-Id: I5f82510b6d39b53bcf6f1006dd83bdd9053963a0
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/1456845
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index 8ea2929f..7f110821 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -461,6 +461,25 @@ int gk20a_init_gpu_characteristics(struct gk20a *g)
         if (gk20a_platform_has_syncpoints(g))
                 gpu->flags |= NVGPU_GPU_FLAGS_HAS_SYNCPOINTS;
 
+        /*
+         * Railgating needs job tracking which prevents fast submits. They're
+         * supported otherwise, provided that the user doesn't request anything
+         * that depends on job tracking. (Here, fast means strictly no
+         * metadata, just the gpfifo contents are copied and gp_put updated).
+         */
+        if (!platform->can_railgate)
+                gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_NO_JOBTRACKING;
+
+        /*
+         * Railgating and sync framework require deferred job cleanup which
+         * prevents deterministic submits. They're supported otherwise,
+         * provided that the user doesn't request anything that depends on
+         * deferred cleanup.
+         */
+        if (!platform->can_railgate
+            && !gk20a_channel_sync_needs_sync_framework(g))
+                gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_DETERMINISTIC_SUBMIT_FULL;
+
         gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_USERSPACE_MANAGED_AS;
         gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_TSG;
         gpu->flags |= NVGPU_GPU_FLAGS_SUPPORT_MAP_COMPBITS;