gpu: nvgpu: support tuning per-ch deterministic opts

Add a new ioctl NVGPU_GPU_IOCTL_SET_DETERMINISTIC_OPTS to adjust
deterministic options on a per-channel basis. Currently, the only
supported option is to relax the no-railgating requirement on open
deterministic channels. This also disallows submits on such channels,
until the railgate option is reset.

Bug 200327089

Change-Id: If4f0f51fd1d40ad7407d13638150d7402479aff0
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/1554563
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

3 files changed, 8 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index 805902eb..6c607ae2 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -578,7 +578,10 @@ unbind:
         if (ch->deterministic) {
                 nvgpu_rwsem_down_read(&g->deterministic_busy);
                 ch->deterministic = false;
-                gk20a_idle(g);
+                if (!ch->deterministic_railgate_allowed)
+                        gk20a_idle(g);
+                ch->deterministic_railgate_allowed = false;
+
                 nvgpu_rwsem_up_read(&g->deterministic_busy);
         }
 
diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
index 762daea9..0cb60200 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.h
@@ -208,6 +208,8 @@ struct channel_gk20a {
         bool first_init;
         bool vpr;
         bool deterministic;
+        /* deterministic, but explicitly idle and submits disallowed */
+        bool deterministic_railgate_allowed;
         bool cde;
         pid_t pid;
         pid_t tgid;
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index e8db9d2c..756db415 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -439,6 +439,8 @@ int gk20a_init_gpu_characteristics(struct gk20a *g)
                                 NVGPU_SUPPORT_DETERMINISTIC_SUBMIT_FULL,
                                 true);
 
+        __nvgpu_set_enabled(g, NVGPU_SUPPORT_DETERMINISTIC_OPTS, true);
+
         __nvgpu_set_enabled(g, NVGPU_SUPPORT_USERSPACE_MANAGED_AS, true);
         __nvgpu_set_enabled(g, NVGPU_SUPPORT_TSG, true);