[Intel-gfx] [PATCH 1/2] drm/i915/display/vlv: fix pixel overlap register update

[Andrzej Hajda]

To update properly bits in the register the mask should be used
to clear old value and then the result should be or-ed with new
value, for such updates there is separate helper intel_de_rmw.

Signed-off-by: Andrzej Hajda <andrzej.ha...@intel.com>
---
 drivers/gpu/drm/i915/display/vlv_dsi.c | 24 +++++++++---------------
 1 file changed, 9 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/vlv_dsi.c 
b/drivers/gpu/drm/i915/display/vlv_dsi.c
index 662bdb656aa304..f5268997a3e172 100644
--- a/drivers/gpu/drm/i915/display/vlv_dsi.c
+++ b/drivers/gpu/drm/i915/display/vlv_dsi.c
@@ -649,23 +649,17 @@ static void intel_dsi_port_enable(struct intel_encoder 
*encoder,
        enum port port;
 
        if (intel_dsi->dual_link == DSI_DUAL_LINK_FRONT_BACK) {
-               u32 temp;
+               u32 temp = intel_dsi->pixel_overlap;
+
                if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv)) {
-                       for_each_dsi_port(port, intel_dsi->ports) {
-                               temp = intel_de_read(dev_priv,
-                                                    MIPI_CTRL(port));
-                               temp &= ~BXT_PIXEL_OVERLAP_CNT_MASK |
-                                       intel_dsi->pixel_overlap <<
-                                       BXT_PIXEL_OVERLAP_CNT_SHIFT;
-                               intel_de_write(dev_priv, MIPI_CTRL(port),
-                                              temp);
-                       }
+                       for_each_dsi_port(port, intel_dsi->ports)
+                               intel_de_rmw(dev_priv, MIPI_CTRL(port),
+                                            BXT_PIXEL_OVERLAP_CNT_MASK,
+                                            temp << 
BXT_PIXEL_OVERLAP_CNT_SHIFT);
                } else {
-                       temp = intel_de_read(dev_priv, VLV_CHICKEN_3);
-                       temp &= ~PIXEL_OVERLAP_CNT_MASK |
-                                       intel_dsi->pixel_overlap <<
-                                       PIXEL_OVERLAP_CNT_SHIFT;
-                       intel_de_write(dev_priv, VLV_CHICKEN_3, temp);
+                       intel_de_rmw(dev_priv, VLV_CHICKEN_3,
+                                    PIXEL_OVERLAP_CNT_MASK,
+                                    temp << PIXEL_OVERLAP_CNT_SHIFT);
                }
        }
 
-- 
2.34.1