gpu: nvgpu: Remove get and put client routines

gk20a_get_client() and gk20a_put_client() routines are effectively dead
code. The GPU has been using pm_runtime for reference counting whether
the device should be turned on or off, and gk20a_get_client() and
gk20a_put_client() have had no positive effect on the behaviour.

In worst case these functions trigger some issues as they may trigger
code paths that should not be run. There is also a race between get/put
and busy/idle.

This patch removes the functions and reworks as_gk20a.c to correctly use
gk20a_busy()/gk20a_idle() where put/get was required.

Additionally, finalize_poweron() is moved to gk20a_busy(), similarly as
it was with gk20a_get_client(). If pm_runtime is not in use, the device
is only powered on and never off. Currently this affects vgpu power
management since it does not use pm_runtime yet.

Bug 1562096

Change-Id: I3162655f83457e9caccd9264eed36b5d51e60c52
Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Signed-off-by: Konsta Holtta <kholtta@nvidia.com>
Reviewed-on: http://git-master/r/414998
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Seshendra Gadagottu <sgadagottu@nvidia.com>
Tested-by: Seshendra Gadagottu <sgadagottu@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>

1 files changed, 0 insertions, 10 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
index bcc05079..eaea5a77 100644
--- a/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/channel_gk20a.c
@@ -726,7 +726,6 @@ int gk20a_channel_release(struct inode *inode, struct file *filp)
         gk20a_free_channel(ch, true);
         gk20a_idle(ch->g->dev);
 
-        gk20a_put_client(g);
         filp->private_data = NULL;
         return 0;
 }
@@ -788,23 +787,14 @@ static int __gk20a_channel_open(struct gk20a *g, struct file *filp)
 
         trace_gk20a_channel_open(dev_name(&g->dev->dev));
 
-        err = gk20a_get_client(g);
-        if (err) {
-                gk20a_err(dev_from_gk20a(g),
-                        "failed to get client ref");
-                return err;
-        }
-
         err = gk20a_busy(g->dev);
         if (err) {
-                gk20a_put_client(g);
                 gk20a_err(dev_from_gk20a(g), "failed to power on, %d", err);
                 return err;
         }
         ch = gk20a_open_new_channel(g);
         gk20a_idle(g->dev);
         if (!ch) {
-                gk20a_put_client(g);
                 gk20a_err(dev_from_gk20a(g),
                         "failed to get f");
                 return -ENOMEM;