drm/i915/skl: If needed sanitize bios programmed cdclk
Especially in cases where pre-os does not enable display, cdclk might
not be in sane state. During sanitization initialize cdclk with maximum
value till we get dynamic cdclk support.
v2: Check if BIOS programmed correctly rather than always calling init
- Do validation of programmed cdctl and what it is expected
- Only do slk_init_cdclk if validation failed else reuse BIOS
programmed value
v3: Move the validation logic in a separate sanitize function (Ville)
v4: No need to check LCPLL after sanitize and use max_cdclk_freq instead
of hardcoded value (Ville)
Cc: Imre Deak <imre.deak@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1445344992-14658-1-git-send-email-shobhit.kumar@intel.com
Reviewed-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_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index b25e99a..824b863 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -2949,8 +2949,8 @@
cdclk_freq = dev_priv->display.get_display_clock_speed(dev);
dev_priv->skl_boot_cdclk = cdclk_freq;
- if (!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_ENABLE))
- DRM_ERROR("LCPLL1 is disabled\n");
+ if (skl_sanitize_cdclk(dev_priv))
+ DRM_DEBUG_KMS("Sanitized cdclk programmed by pre-os\n");
else
intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS);
} else if (IS_BROXTON(dev)) {