drm/i915: fix CB tuning check for ILK+

CB tuning is needed to handle potential process variations that might
cause clock jitter for certain PLL settings.  However, we were setting
it incorrectly since we were using the wrong M value as a check (M1 when
we needed to use the whole M value).  Fix it up, making my HDMI
attached display a little prettier (used to have occasional dots crawl
across the display).

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 8f7ed73..32c8c95 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -4994,7 +4994,7 @@ static int ironlake_crtc_mode_set(struct drm_crtc *crtc,
        } else if (is_sdvo && is_tv)
                factor = 20;
 
-       if (clock.m1 < factor * clock.n)
+       if (clock.m < factor * clock.n)
                fp |= FP_CB_TUNE;
 
        dpll = 0;