drm/i915: Add ILK/SNB/IVB WM latency field support

Add a new function  ilk_wm_lp_latency() which will tell us what to write
into the WM_LPx register latency field. HSW is different from erlier
gens in this regard.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 12 insertions, 1 deletions

diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index be8244282742..dbd025a4f22f 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2715,6 +2715,17 @@ static int ilk_wm_lp_to_level(int wm_lp, const struct intel_pipe_wm *pipe_wm)
         return wm_lp + (wm_lp >= 2 && pipe_wm->wm[4].enable);
 }
 
+/* The value we need to program into the WM_LPx latency field */
+static unsigned int ilk_wm_lp_latency(struct drm_device *dev, int level)
+{
+        struct drm_i915_private *dev_priv = dev->dev_private;
+
+        if (IS_HASWELL(dev))
+                return 2 * level;
+        else
+                return dev_priv->wm.pri_latency[level];
+}
+
 static void hsw_compute_wm_results(struct drm_device *dev,
                                    const struct intel_pipe_wm *merged,
                                    enum intel_ddb_partitioning partitioning,
@@ -2737,7 +2748,7 @@ static void hsw_compute_wm_results(struct drm_device *dev,
                         break;
 
                 results->wm_lp[wm_lp - 1] = WM3_LP_EN |
-                        ((level * 2) << WM1_LP_LATENCY_SHIFT) |
+                        (ilk_wm_lp_latency(dev, level) << WM1_LP_LATENCY_SHIFT) |
                         (r->pri_val << WM1_LP_SR_SHIFT) |
                         r->cur_val;