drm/i915/sdvo: Preserve pixel-multiplier

Store the pixel-multiplier on the adjusted mode and avoid modifying the
requested mode.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 16 insertions, 9 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index adce19304eee..120a9c0c2da6 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3519,7 +3519,6 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
         int trans_dpll_sel = (pipe == 0) ? 0 : 1;
         int lvds_reg = LVDS;
         u32 temp;
-        int sdvo_pixel_multiply;
         int target_clock;
 
         drm_vblank_pre_modeset(dev, pipe);
@@ -3770,12 +3769,14 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
                 else
                         dpll |= DPLLB_MODE_DAC_SERIAL;
                 if (is_sdvo) {
+                        int pixel_multiplier = intel_mode_get_pixel_multiplier(adjusted_mode);
+                        if (pixel_multiplier > 1) {
+                                if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
+                                        dpll |= (pixel_multiplier - 1) << SDVO_MULTIPLIER_SHIFT_HIRES;
+                                else if (HAS_PCH_SPLIT(dev))
+                                        dpll |= (pixel_multiplier - 1) << PLL_REF_SDVO_HDMI_MULTIPLIER_SHIFT;
+                        }
                         dpll |= DPLL_DVO_HIGH_SPEED;
-                        sdvo_pixel_multiply = adjusted_mode->clock / mode->clock;
-                        if (IS_I945G(dev) || IS_I945GM(dev) || IS_G33(dev))
-                                dpll |= (sdvo_pixel_multiply - 1) << SDVO_MULTIPLIER_SHIFT_HIRES;
-                        else if (HAS_PCH_SPLIT(dev))
-                                dpll |= (sdvo_pixel_multiply - 1) << PLL_REF_SDVO_HDMI_MULTIPLIER_SHIFT;
                 }
                 if (is_dp)
                         dpll |= DPLL_DVO_HIGH_SPEED;
@@ -3982,9 +3983,15 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
 
                 if (IS_I965G(dev) && !HAS_PCH_SPLIT(dev)) {
                         if (is_sdvo) {
-                                sdvo_pixel_multiply = adjusted_mode->clock / mode->clock;
-                                I915_WRITE(dpll_md_reg, (0 << DPLL_MD_UDI_DIVIDER_SHIFT) |
-                                        ((sdvo_pixel_multiply - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT));
+                                int pixel_multiplier = intel_mode_get_pixel_multiplier(adjusted_mode);
+                                if (pixel_multiplier > 1)
+                                        pixel_multiplier = (pixel_multiplier - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT;
+                                else
+                                        pixel_multiplier = 0;
+
+                                I915_WRITE(dpll_md_reg,
+                                           (0 << DPLL_MD_UDI_DIVIDER_SHIFT) |
+                                           pixel_multiplier);
                         } else
                                 I915_WRITE(dpll_md_reg, 0);
                 } else {