1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/gpu/drm/radeon/atombios_crtc.c b/drivers/gpu/drm/radeon/atombios_crtc.c
index a97abc8af657..1dcf39084555 100644
--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -627,7 +627,9 @@ static u32 atombios_adjust_pll(struct drm_crtc *crtc,
                         if (radeon_crtc->ss.refdiv) {
                                 radeon_crtc->pll_flags |= RADEON_PLL_USE_REF_DIV;
                                 radeon_crtc->pll_reference_div = radeon_crtc->ss.refdiv;
-                                if (rdev->family >= CHIP_RV770)
+                                if (ASIC_IS_AVIVO(rdev) &&
+                                    rdev->family != CHIP_RS780 &&
+                                    rdev->family != CHIP_RS880)
                                         radeon_crtc->pll_flags |= RADEON_PLL_USE_FRAC_FB_DIV;
                         }
                 }