gpu: nvgpu: Expose PMU security mode in debugfs

Expose a debugfs entry pmu_security. It allows checking if PMU was
booted in secure or non-secure mode.

Change-Id: Iea584b696440779bee0900edccabd4e5b2997805
Signed-off-by: Terje Bergstrom <tbergstrom@nvidia.com>
Reviewed-on: http://git-master/r/552456

1 files changed, 27 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
index eb79fe17..f7af9035 100644
--- a/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/pmu_gk20a.c
@@ -4123,6 +4123,27 @@ static const struct file_operations perfmon_events_count_fops = {
         .release        = single_release,
 };
 
+static int security_show(struct seq_file *s, void *data)
+{
+        struct gk20a *g = s->private;
+
+        seq_printf(s, "%d\n", g->pmu.pmu_mode);
+        return 0;
+
+}
+
+static int security_open(struct inode *inode, struct file *file)
+{
+        return single_open(file, security_show, inode->i_private);
+}
+
+static const struct file_operations security_fops = {
+        .open           = security_open,
+        .read           = seq_read,
+        .llseek         = seq_lseek,
+        .release        = single_release,
+};
+
 int gk20a_pmu_debugfs_init(struct platform_device *dev)
 {
         struct dentry *d;
@@ -4158,8 +4179,13 @@ int gk20a_pmu_debugfs_init(struct platform_device *dev)
                                                 &perfmon_events_count_fops);
         if (!d)
                 goto err_out;
-        return 0;
 
+        d = debugfs_create_file(
+                "pmu_security", S_IRUGO, platform->debugfs, g,
+                                                &security_fops);
+        if (!d)
+                goto err_out;
+        return 0;
 err_out:
         pr_err("%s: Failed to make debugfs node\n", __func__);
         debugfs_remove_recursive(platform->debugfs);