drm/i915: De-magic the VLV p2 divider step size

The p2 divider on VLV needs to be even when it's > 10. The current code
to make that happen is rather weird. Just make the step size adjustement
in the for loop decrement step.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index d984b10831a7da279f08e7a0f571f7a570153ddf..62cfada507358c1c243df4e65f06e2ca12095d0f 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -688,9 +688,8 @@ vlv_find_best_dpll(const intel_limit_t *limit, struct drm_crtc *crtc,
        /* based on hardware requirement, prefer smaller n to precision */
        for (clock.n = limit->n.min; clock.n <= ((refclk) / minupdate); clock.n++) {
                for (clock.p1 = limit->p1.max; clock.p1 > limit->p1.min; clock.p1--) {
-                       for (clock.p2 = limit->p2.p2_fast+1; clock.p2 > 0; clock.p2--) {
-                               if (clock.p2 > 10)
-                                       clock.p2--;
+                       for (clock.p2 = limit->p2.p2_fast; clock.p2 > 0;
+                            clock.p2 -= clock.p2 > 10 ? 2 : 1) {
                                clock.p = clock.p1 * clock.p2;
                                /* based on hardware requirement, prefer bigger m1,m2 values */
                                for (clock.m1 = limit->m1.min; clock.m1 <= limit->m1.max; clock.m1++) {