drm/radeon/kms: switch to condition waiting for reclocking

We tried to implement interruptible waiting with timeout (it was broken
anyway) which was not a good idea as explained by Andrew. It's possible
to avoid using additional variable but actually it inroduces using more
complex in-kernel tools. So simply add one variable for condition.
Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/radeon/r100.c

@@ -312,10 +312,12 @@ int r100_irq_process(struct radeon_device *rdev)
 		/* Vertical blank interrupts */
 		if (status & RADEON_CRTC_VBLANK_STAT) {
 			drm_handle_vblank(rdev->ddev, 0);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (status & RADEON_CRTC2_VBLANK_STAT) {
 			drm_handle_vblank(rdev->ddev, 1);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (status & RADEON_FP_DETECT_STAT) {

drivers/gpu/drm/radeon/r600.c

@@ -2765,6 +2765,7 @@ int r600_irq_process(struct radeon_device *rdev)
 			case 0: /* D1 vblank */
 				if (disp_int & LB_D1_VBLANK_INTERRUPT) {
 					drm_handle_vblank(rdev->ddev, 0);
+					rdev->pm.vblank_sync = true;
 					wake_up(&rdev->irq.vblank_queue);
 					disp_int &= ~LB_D1_VBLANK_INTERRUPT;
 					DRM_DEBUG("IH: D1 vblank\n");
@@ -2786,6 +2787,7 @@ int r600_irq_process(struct radeon_device *rdev)
 			case 0: /* D2 vblank */
 				if (disp_int & LB_D2_VBLANK_INTERRUPT) {
 					drm_handle_vblank(rdev->ddev, 1);
+					rdev->pm.vblank_sync = true;
 					wake_up(&rdev->irq.vblank_queue);
 					disp_int &= ~LB_D2_VBLANK_INTERRUPT;
 					DRM_DEBUG("IH: D2 vblank\n");

drivers/gpu/drm/radeon/radeon.h

@@ -687,6 +687,7 @@ struct radeon_pm {
 	bool 			downclocked;
 	int			active_crtcs;
 	int			req_vblank;
+	bool			vblank_sync;
 	fixed20_12		max_bandwidth;
 	fixed20_12		igp_sideport_mclk;
 	fixed20_12		igp_system_mclk;

drivers/gpu/drm/radeon/radeon_pm.c

@@ -353,10 +353,12 @@ static void radeon_pm_set_clocks(struct radeon_device *rdev)
 		rdev->pm.req_vblank |= (1 << 1);
 		drm_vblank_get(rdev->ddev, 1);
 	}
-	if (rdev->pm.active_crtcs)
-		wait_event_interruptible_timeout(
-			rdev->irq.vblank_queue, 0,
+	if (rdev->pm.active_crtcs) {
+		rdev->pm.vblank_sync = false;
+		wait_event_timeout(
+			rdev->irq.vblank_queue, rdev->pm.vblank_sync,
 			msecs_to_jiffies(RADEON_WAIT_VBLANK_TIMEOUT));
+	}
 	if (rdev->pm.req_vblank & (1 << 0)) {
 		rdev->pm.req_vblank &= ~(1 << 0);
 		drm_vblank_put(rdev->ddev, 0);

drivers/gpu/drm/radeon/rs600.c

@@ -392,10 +392,12 @@ int rs600_irq_process(struct radeon_device *rdev)
 		/* Vertical blank interrupts */
 		if (G_007EDC_LB_D1_VBLANK_INTERRUPT(r500_disp_int)) {
 			drm_handle_vblank(rdev->ddev, 0);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (G_007EDC_LB_D2_VBLANK_INTERRUPT(r500_disp_int)) {
 			drm_handle_vblank(rdev->ddev, 1);
+			rdev->pm.vblank_sync = true;
 			wake_up(&rdev->irq.vblank_queue);
 		}
 		if (G_007EDC_DC_HOT_PLUG_DETECT1_INTERRUPT(r500_disp_int)) {