diff --git a/drivers/gpu/drm/radeon/r100.c b/drivers/gpu/drm/radeon/r100.c
index bfd36ab643a6..18cd84fae99c 100644
--- a/drivers/gpu/drm/radeon/r100.c
+++ b/drivers/gpu/drm/radeon/r100.c
@@ -789,9 +789,7 @@ int r100_irq_process(struct radeon_device *rdev)
 			WREG32(RADEON_AIC_CNTL, msi_rearm | RS400_MSI_REARM);
 			break;
 		default:
-			msi_rearm = RREG32(RADEON_MSI_REARM_EN) & ~RV370_MSI_REARM_EN;
-			WREG32(RADEON_MSI_REARM_EN, msi_rearm);
-			WREG32(RADEON_MSI_REARM_EN, msi_rearm | RV370_MSI_REARM_EN);
+			WREG32(RADEON_MSI_REARM_EN, RV370_MSI_REARM_EN);
 			break;
 		}
 	}
diff --git a/drivers/gpu/drm/radeon/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index ec46eb45e34c..c05865e5521f 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -684,9 +684,7 @@ int rs600_irq_process(struct radeon_device *rdev)
 			WREG32(RADEON_BUS_CNTL, msi_rearm | RS600_MSI_REARM);
 			break;
 		default:
-			msi_rearm = RREG32(RADEON_MSI_REARM_EN) & ~RV370_MSI_REARM_EN;
-			WREG32(RADEON_MSI_REARM_EN, msi_rearm);
-			WREG32(RADEON_MSI_REARM_EN, msi_rearm | RV370_MSI_REARM_EN);
+			WREG32(RADEON_MSI_REARM_EN, RV370_MSI_REARM_EN);
 			break;
 		}
 	}