gpu: nvgpu: introduce nvgpu_enable_irqs

Prepare function to enable the stall and non-stall kernel interrupts.
Update the type of irq state irqs_enabled to bool.

JIRA NVGPU-1592

Change-Id: I758794e0f230814a0bea2f3c035562e9a5c7e0ea
Signed-off-by: Sagar Kamble <skamble@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/2203859
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: svc-mobile-misra <svc-mobile-misra@nvidia.com>
Reviewed-by: Philip Elcan <pelcan@nvidia.com>
GVS: Gerrit_Virtual_Submit
Reviewed-by: Vijayakumar Subbu <vsubbu@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>

drivers/gpu/nvgpu/include/nvgpu/gk20a.h

@@ -1850,7 +1850,7 @@ struct gk20a {
 	struct nvgpu_cond sw_irq_nonstall_last_handled_cond;
 	nvgpu_atomic_t sw_irq_nonstall_last_handled;
 
-	int irqs_enabled;
+	bool irqs_enabled;
 	u32 irq_stall; /* can be same as irq_nonstall in case of PCI */
 	u32 irq_nonstall;
 

drivers/gpu/nvgpu/include/nvgpu/nvgpu_init.h

@@ -136,6 +136,15 @@ void nvgpu_sw_quiesce(struct gk20a *g);
  */
 void nvgpu_start_gpu_idle(struct gk20a *g);
 
+/**
+ * @brief Enable interrupt handlers
+ *
+ * @param g [in] The GPU
+ *
+ * Enable interrupt handlers.
+ */
+int nvgpu_enable_irqs(struct gk20a *g);
+
 /**
  * @brief Disable interrupt handlers
  *

drivers/gpu/nvgpu/os/linux/module.c

@@ -487,10 +487,11 @@ int gk20a_pm_finalize_poweron(struct device *dev)
 	trace_gk20a_finalize_poweron_done(dev_name(dev));
 #endif
 
-	enable_irq(g->irq_stall);
+	err = nvgpu_enable_irqs(g);
-	if (g->irq_stall != g->irq_nonstall)
+	if (err) {
-		enable_irq(g->irq_nonstall);
+		nvgpu_err(g, "failed to enable irqs %d", err);
-	g->irqs_enabled = 1;
+		goto done;
+	}
 
 	gk20a_scale_resume(dev_from_gk20a(g));
 
@@ -534,13 +535,25 @@ static int gk20a_lockout_registers(struct gk20a *g)
 	return 0;
 }
 
+int nvgpu_enable_irqs(struct gk20a *g)
+{
+	if (!g->irqs_enabled) {
+		enable_irq(g->irq_stall);
+		if (g->irq_stall != g->irq_nonstall)
+			enable_irq(g->irq_nonstall);
+		g->irqs_enabled = true;
+	}
+
+	return 0;
+}
+
 void nvgpu_disable_irqs(struct gk20a *g)
 {
 	if (g->irqs_enabled) {
 		disable_irq(g->irq_stall);
 		if (g->irq_stall != g->irq_nonstall)
 			disable_irq(g->irq_nonstall);
-		g->irqs_enabled = 0;
+		g->irqs_enabled = false;
 	}
 }
 
@@ -552,7 +565,7 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
 #endif
 	struct gk20a_platform *platform = gk20a_get_platform(dev);
 	bool irqs_enabled;
-	int ret = 0;
+	int ret = 0, err = 0;
 
 	nvgpu_log_fn(g, " ");
 
@@ -589,10 +602,10 @@ static int gk20a_pm_prepare_poweroff(struct device *dev)
 error:
 	/* re-enabled IRQs if previously enabled */
 	if (irqs_enabled) {
-		enable_irq(g->irq_stall);
+		err = nvgpu_enable_irqs(g);
-		if (g->irq_stall != g->irq_nonstall)
+		if (err) {
-			enable_irq(g->irq_nonstall);
+			nvgpu_err(g, "failed to enable irqs %d", err);
-		g->irqs_enabled = 1;
+		}
 	}
 
 	gk20a_scale_resume(dev);

drivers/gpu/nvgpu/os/posix/nvgpu.c

@@ -63,6 +63,11 @@ void nvgpu_start_gpu_idle(struct gk20a *g)
 	nvgpu_set_enabled(g, NVGPU_DRIVER_IS_DYING, true);
 }
 
+int nvgpu_enable_irqs(struct gk20a *g)
+{
+	return 0;
+}
+
 void nvgpu_disable_irqs(struct gk20a *g)
 {
 }