drm: tegra: program only one window during modeset

The intention is to program exactly WIN_A, not WIN_A and possibly
others.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/gpu/drm/tegra/dc.c b/drivers/gpu/drm/tegra/dc.c
index b256574409e7..3475bd9f9719 100644
--- a/drivers/gpu/drm/tegra/dc.c
+++ b/drivers/gpu/drm/tegra/dc.c
@@ -223,8 +223,7 @@ static int tegra_crtc_mode_set(struct drm_crtc *crtc,
         win.stride = crtc->fb->pitches[0];
 
         /* program window registers */
-        value = tegra_dc_readl(dc, DC_CMD_DISPLAY_WINDOW_HEADER);
-        value |= WINDOW_A_SELECT;
+        value = WINDOW_A_SELECT;
         tegra_dc_writel(dc, value, DC_CMD_DISPLAY_WINDOW_HEADER);
 
         tegra_dc_writel(dc, win.fmt, DC_WIN_COLOR_DEPTH);