1 files changed, 30 insertions, 1 deletions

diff --git a/drivers/gpu/nvgpu/tegra/linux/platform_gk20a_tegra.c b/drivers/gpu/nvgpu/tegra/linux/platform_gk20a_tegra.c
index d6e448d8..a3b73cdf 100644
--- a/drivers/gpu/nvgpu/tegra/linux/platform_gk20a_tegra.c
+++ b/drivers/gpu/nvgpu/tegra/linux/platform_gk20a_tegra.c
@@ -754,6 +754,27 @@ void gk20a_tegra_init_secure_alloc(struct gk20a *g)
 }
 
 #ifdef CONFIG_COMMON_CLK
+static struct clk *gk20a_clk_get(struct gk20a *g)
+{
+        if (!g->clk.tegra_clk) {
+                struct clk *clk;
+                char clk_dev_id[32];
+                struct device *dev = dev_from_gk20a(g);
+
+                snprintf(clk_dev_id, 32, "tegra_%s", dev_name(dev));
+
+                clk = clk_get_sys(clk_dev_id, "gpu");
+                if (IS_ERR(clk)) {
+                        nvgpu_err(g, "fail to get tegra gpu clk %s/gpu\n",
+                                  clk_dev_id);
+                        return NULL;
+                }
+                g->clk.tegra_clk = clk;
+        }
+
+        return g->clk.tegra_clk;
+}
+
 static int gm20b_clk_prepare_ops(struct clk_hw *hw)
 {
         struct clk_gk20a *clk = to_clk_gk20a(hw);
@@ -809,6 +830,10 @@ static int gm20b_register_gpcclk(struct gk20a *g)
         struct clk *c;
         int err = 0;
 
+        /* make sure the clock is available */
+        if (!gk20a_clk_get(g))
+                return -ENOSYS;
+
         err = gm20b_init_clk_setup_sw(g);
         if (err)
                 return err;
@@ -958,7 +983,11 @@ static long gk20a_round_clk_rate(struct device *dev, unsigned long rate)
         struct gk20a_platform *platform = gk20a_get_platform(dev);
         struct gk20a *g = platform->g;
 
-        return gk20a_clk_round_rate(g, rate);
+        /* make sure the clock is available */
+        if (!gk20a_clk_get(g))
+                return rate;
+
+        return clk_round_rate(clk_get_parent(g->clk.tegra_clk), rate);
 }
 
 static int gk20a_clk_get_freqs(struct device *dev,