gpu: nvgpu: use usleep_range instead of msleep

msleep is not recommended for (1ms - 20ms). So use usleep_range
instead to have a more deterministic sleep time.

Also fix the print for target_ref_count that could either be 2 or
1 based on whether GPU rail-gating is enabled or not.

Bug 200294536

Change-Id: I26c9ed8a1badc84db5efa89347a227e6b46f603c
Signed-off-by: Bharat Nihalani <bnihalani@nvidia.com>
Reviewed-on: http://git-master/r/1500409
Reviewed-on: http://git-master/r/1503628
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
Tested-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-by: Automatic_Commit_Validation_User

2 files changed, 4 insertions, 4 deletions

diff --git a/drivers/gpu/nvgpu/common/linux/module.c b/drivers/gpu/nvgpu/common/linux/module.c
index 80c516a6..7c7cc714 100644
--- a/drivers/gpu/nvgpu/common/linux/module.c
+++ b/drivers/gpu/nvgpu/common/linux/module.c
@@ -337,12 +337,12 @@ int __gk20a_do_idle(struct gk20a *g, bool force_reset)
 
         /* check and wait until GPU is idle (with a timeout) */
         do {
-                nvgpu_msleep(1);
+                nvgpu_usleep_range(1000, 1100);
                 ref_cnt = atomic_read(&dev->power.usage_count);
         } while (ref_cnt != target_ref_cnt && !nvgpu_timeout_expired(&timeout));
 
         if (ref_cnt != target_ref_cnt) {
-                nvgpu_err(g, "failed to idle - refcount %d != 1",
+                nvgpu_err(g, "failed to idle - refcount %d != target_ref_cnt",
                         ref_cnt);
                 goto fail_drop_usage_count;
         }
@@ -367,7 +367,7 @@ int __gk20a_do_idle(struct gk20a *g, bool force_reset)
 
                 /* check in loop if GPU is railgated or not */
                 do {
-                        nvgpu_msleep(1);
+                        nvgpu_usleep_range(1000, 1100);
                         is_railgated = platform->is_railgated(dev);
                 } while (!is_railgated && !nvgpu_timeout_expired(&timeout));
 
diff --git a/drivers/gpu/nvgpu/common/pmu/pmu.c b/drivers/gpu/nvgpu/common/pmu/pmu.c
index 15b57988..35422e0d 100644
--- a/drivers/gpu/nvgpu/common/pmu/pmu.c
+++ b/drivers/gpu/nvgpu/common/pmu/pmu.c
@@ -357,7 +357,7 @@ static int nvgpu_pg_init_task(void *arg)
         }
 
         while (!nvgpu_thread_should_stop(&pg_init->state_task))
-                nvgpu_msleep(5);
+                nvgpu_usleep_range(5000, 5100);
 
         nvgpu_log_fn(g, "thread exit");