drm/i915: Disable primary plane trickle feed for g4x

The docs say that the trickle feed disable bit is present (for primary
planes only, not video sprites) on CTG, and that it must be set
for ELK. Just set it for all g4x chipsets.

v2: Do it in init_clock_gating too

Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

2 files changed, 12 insertions, 0 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8d9e7c0e9e4b..3f025ee299dd 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -1958,6 +1958,9 @@ static int i9xx_update_plane(struct drm_crtc *crtc, struct drm_framebuffer *fb,
                         dspcntr &= ~DISPPLANE_TILED;
         }
 
+        if (IS_G4X(dev))
+                dspcntr |= DISPPLANE_TRICKLE_FEED_DISABLE;
+
         I915_WRITE(reg, dspcntr);
 
         linear_offset = y * fb->pitches[0] + x * (fb->bits_per_pixel / 8);
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index a417d7b196c2..47f3c48cd3c2 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -4908,6 +4908,7 @@ static void g4x_init_clock_gating(struct drm_device *dev)
 {
         struct drm_i915_private *dev_priv = dev->dev_private;
         uint32_t dspclk_gate;
+        int pipe;
 
         I915_WRITE(RENCLK_GATE_D1, 0);
         I915_WRITE(RENCLK_GATE_D2, VF_UNIT_CLOCK_GATE_DISABLE |
@@ -4924,6 +4925,14 @@ static void g4x_init_clock_gating(struct drm_device *dev)
         /* WaDisableRenderCachePipelinedFlush */
         I915_WRITE(CACHE_MODE_0,
                    _MASKED_BIT_ENABLE(CM0_PIPELINED_RENDER_FLUSH_DISABLE));
+
+        for_each_pipe(pipe) {
+                I915_WRITE(DSPCNTR(pipe),
+                           I915_READ(DSPCNTR(pipe)) |
+                           DISPPLANE_TRICKLE_FEED_DISABLE);
+                intel_flush_display_plane(dev_priv, pipe);
+        }
+
 }
 
 static void crestline_init_clock_gating(struct drm_device *dev)