drm/radeon: replace pflip and sw_int counters with atomics

So we can skip the locking. Also renames sw_int to
ring_int, cause that better matches its purpose.

Signed-off-by: Christian Koenig <christian.koenig@amd.com>
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index f9aee25..e11bc46 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -564,18 +564,18 @@
 		WREG32(R_000040_GEN_INT_CNTL, 0);
 		return -EINVAL;
 	}
-	if (rdev->irq.sw_int[RADEON_RING_TYPE_GFX_INDEX]) {
+	if (atomic_read(&rdev->irq.ring_int[RADEON_RING_TYPE_GFX_INDEX])) {
 		tmp |= S_000040_SW_INT_EN(1);
 	}
 	if (rdev->irq.gui_idle) {
 		tmp |= S_000040_GUI_IDLE(1);
 	}
 	if (rdev->irq.crtc_vblank_int[0] ||
-	    rdev->irq.pflip[0]) {
+	    atomic_read(&rdev->irq.pflip[0])) {
 		mode_int |= S_006540_D1MODE_VBLANK_INT_MASK(1);
 	}
 	if (rdev->irq.crtc_vblank_int[1] ||
-	    rdev->irq.pflip[1]) {
+	    atomic_read(&rdev->irq.pflip[1])) {
 		mode_int |= S_006540_D2MODE_VBLANK_INT_MASK(1);
 	}
 	if (rdev->irq.hpd[0]) {
@@ -695,7 +695,7 @@
 				rdev->pm.vblank_sync = true;
 				wake_up(&rdev->irq.vblank_queue);
 			}
-			if (rdev->irq.pflip[0])
+			if (atomic_read(&rdev->irq.pflip[0]))
 				radeon_crtc_handle_flip(rdev, 0);
 		}
 		if (G_007EDC_LB_D2_VBLANK_INTERRUPT(rdev->irq.stat_regs.r500.disp_int)) {
@@ -704,7 +704,7 @@
 				rdev->pm.vblank_sync = true;
 				wake_up(&rdev->irq.vblank_queue);
 			}
-			if (rdev->irq.pflip[1])
+			if (atomic_read(&rdev->irq.pflip[1]))
 				radeon_crtc_handle_flip(rdev, 1);
 		}
 		if (G_007EDC_DC_HOT_PLUG_DETECT1_INTERRUPT(rdev->irq.stat_regs.r500.disp_int)) {