gpu: nvgpu: return error if GPU not initialized

While writing to sysfs "tpc_fs_mask", we need to have
GPU initialized (we need to have called gk20a_busy()
at least once before)

If this is not happened yet, then return error

Bug 1456969

Change-Id: I09db6bcaa44b8939246cb5ed1205f3fbc0ee0552
Signed-off-by: Deepak Nibade <dnibade@nvidia.com>
Reviewed-on: http://git-master/r/731327
(cherry picked from commit 0dbbcf60bbad6b9a31392d2290a3e26c5daa1e5d)
Reviewed-on: http://git-master/r/731671
Reviewed-by: Automatic_Commit_Validation_User
Reviewed-by: Sachin Nikam <snikam@nvidia.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
index 4fea0779..5fe10273 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a_sysfs.c
@@ -615,6 +615,9 @@ static ssize_t tpc_fs_mask_store(struct device *device,
         if (kstrtoul(buf, 10, &val) < 0)
                 return -EINVAL;
 
+        if (!g->gr.gpc_tpc_mask)
+                return -ENODEV;
+
         if (val && val != g->gr.gpc_tpc_mask[0] && g->ops.gr.set_gpc_tpc_mask) {
                 g->gr.gpc_tpc_mask[0] = val;