drm/i915: Fix the level 0 max_wm hack on VLV/CHV

The watermark should never exceed the FIFO size, so we need to
check against the current FIFO size instead of the theoretical
maximum when we clamp the level 0 watermark.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1480354637-14209-4-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 59a88de83b9adedc3becd21cf7c7de27ad83f0bf..8ff1e23d403b7655527868e24b90a0b9b3419863 100644 (file)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -1132,13 +1132,13 @@ static void vlv_compute_wm(struct intel_crtc *crtc)
                /* normal watermarks */
                for (level = 0; level < wm_state->num_levels; level++) {
                        int wm = vlv_compute_wm_level(plane, crtc, state, level);
-                       int max_wm = plane->base.type == DRM_PLANE_TYPE_CURSOR ? 63 : 511;
+                       int max_wm = plane->wm.fifo_size;
 
                        /* hack */
                        if (WARN_ON(level == 0 && wm > max_wm))
                                wm = max_wm;
 
-                       if (wm > plane->wm.fifo_size)
+                       if (wm > max_wm)
                                break;
 
                        switch (plane->base.type) {