diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.c b/drivers/gpu/nvgpu/gk20a/gk20a.c
index 2310b81c9..c72b87351 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.c
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.c
@@ -164,6 +164,32 @@ static inline u32 sim_readl(struct gk20a *g, u32 r)
 	return readl(g->sim.regs+r);
 }
 
+/*
+ * Locks out the driver from accessing GPU registers. This prevents access to
+ * thse registers after the GPU has been clock or power gated. This should help
+ * find annoying bugs where register reads and writes are silently dropped
+ * after the GPU has been turned off. On older chips these reads and writes can
+ * also lock the entire CPU up.
+ */
+int gk20a_lockout_registers(struct gk20a *g)
+{
+	g->regs = NULL;
+	g->bar1 = NULL;
+
+	return 0;
+}
+
+/*
+ * Undoes gk20a_lockout_registers().
+ */
+int gk20a_restore_registers(struct gk20a *g)
+{
+	g->regs = g->regs_saved;
+	g->bar1 = g->bar1_saved;
+
+	return 0;
+}
+
 static void kunmap_and_free_iopage(void **kvaddr, struct page **page)
 {
 	if (*kvaddr) {
@@ -676,6 +702,9 @@ static int gk20a_init_support(struct platform_device *dev)
 		goto fail;
 	}
 
+	g->regs_saved = g->regs;
+	g->bar1_saved = g->bar1;
+
 	/* Get interrupt numbers */
 	g->irq_nonstall = platform_get_irq(dev, 1);
 	if (g->irq_stall < 0 || g->irq_nonstall < 0) {
@@ -786,6 +815,9 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
 
 	g->power_on = false;
 
+	/* Stop CPU from accessing the GPU registers. */
+	gk20a_lockout_registers(g);
+
 	return ret;
 }
 
@@ -820,6 +852,10 @@ static int gk20a_pm_finalize_poweron(struct device *dev)
 
 	trace_gk20a_finalize_poweron(dev_name(dev));
 
+	err = gk20a_restore_registers(g);
+	if (err)
+		return err;
+
 	nice_value = task_nice(current);
 	set_user_nice(current, -20);
 
diff --git a/drivers/gpu/nvgpu/gk20a/gk20a.h b/drivers/gpu/nvgpu/gk20a/gk20a.h
index 991891c5c..3871eb17f 100644
--- a/drivers/gpu/nvgpu/gk20a/gk20a.h
+++ b/drivers/gpu/nvgpu/gk20a/gk20a.h
@@ -232,9 +232,11 @@ struct gk20a {
 
 	struct resource *reg_mem;
 	void __iomem *regs;
+	void __iomem *regs_saved;
 
 	struct resource *bar1_mem;
 	void __iomem *bar1;
+	void __iomem *bar1_saved;
 
 	bool power_on;
 
@@ -487,6 +489,9 @@ static inline void gk20a_mem_wr32(void *ptr, int w, u32 data)
 }
 
 /* register accessors */
+int gk20a_lockout_registers(struct gk20a *g);
+int gk20a_restore_registers(struct gk20a *g);
+
 static inline void gk20a_writel(struct gk20a *g, u32 r, u32 v)
 {
 	gk20a_dbg(gpu_dbg_reg, " r=0x%x v=0x%x", r, v);