drm/i915: Fix up pipe vs. double wide confusion

Double wide mode is only available on pipe A, except on GDG where
pipe B is also double wide capable.

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

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 9bbb6ea..4dd6561 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4153,10 +4153,10 @@ static int intel_crtc_compute_config(struct intel_crtc *crtc,
                 * Enable pixel doubling when the dot clock
                 * is > 90% of the (display) core speed.
                 *
-                * XXX: No double-wide on 915GM pipe B. Is that
-                * the only reason for the pipe == PIPE_A check?
+                * GDG double wide on either pipe,
+                * otherwise pipe A only.
                 */
-               if (crtc->pipe == PIPE_A &&
+               if ((crtc->pipe == PIPE_A || IS_I915G(dev)) &&
                    adjusted_mode->clock > clock_limit * 9 / 10) {
                        clock_limit *= 2;
                        pipe_config->double_wide = true;