drm/radeon: use fixed PPL ref divider if needed
Signed-off-by: Christian König <christian.koenig@amd.com>
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c
index 2f7cbb9..e6c3c54 100644
--- a/drivers/gpu/drm/radeon/radeon_display.c
+++ b/drivers/gpu/drm/radeon/radeon_display.c
@@ -880,7 +880,12 @@
ref_div_min = pll->reference_div;
else
ref_div_min = pll->min_ref_div;
- ref_div_max = pll->max_ref_div;
+
+ if (pll->flags & RADEON_PLL_USE_FRAC_FB_DIV &&
+ pll->flags & RADEON_PLL_USE_REF_DIV)
+ ref_div_max = pll->reference_div;
+ else
+ ref_div_max = pll->max_ref_div;
/* determine allowed post divider range */
if (pll->flags & RADEON_PLL_USE_POST_DIV) {