Re: [v3] drm/i915/skl: If needed sanitize bios programmed cdclk

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 10/16/2015 06:48 PM, Shobhit Kumar wrote:
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)

Ville, does  this come even close to what you had in mind ?


Cc: Imre Deak <imre.deak@xxxxxxxxx>
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Signed-off-by: Shobhit Kumar <shobhit.kumar@xxxxxxxxx>
---
  drivers/gpu/drm/i915/intel_ddi.c     | 12 ++++++++----
  drivers/gpu/drm/i915/intel_display.c | 31 +++++++++++++++++++++++++++++++
  drivers/gpu/drm/i915/intel_drv.h     |  1 +
  3 files changed, 40 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_ddi.c b/drivers/gpu/drm/i915/intel_ddi.c
index b25e99a..86d43e6 100644
--- a/drivers/gpu/drm/i915/intel_ddi.c
+++ b/drivers/gpu/drm/i915/intel_ddi.c
@@ -2949,10 +2949,14 @@ void intel_ddi_pll_init(struct drm_device *dev)

  		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");
-		else
-			intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS);
+		if (skl_sanitize_cdclk(dev_priv))
+			DRM_DEBUG_KMS("Sanitized cdclk programmed by pre-os\n");
+		else {
+			if (!(I915_READ(LCPLL1_CTL) & LCPLL_PLL_ENABLE))
+				DRM_ERROR("LCPLL1 is disabled\n");
+			else
+				intel_display_power_get(dev_priv, POWER_DOMAIN_PLLS);
+		}
  	} else if (IS_BROXTON(dev)) {
  		broxton_init_cdclk(dev);
  		broxton_ddi_phy_init(dev);
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 5f37f84..98333d3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -5784,6 +5784,37 @@ void skl_init_cdclk(struct drm_i915_private *dev_priv)
  		DRM_ERROR("DBuf power enable timeout\n");
  }

+int skl_sanitize_cdclk(struct drm_i915_private *dev_priv)
+{
+	uint32_t lcpll1 = I915_READ(LCPLL1_CTL);
+	uint32_t cdctl = I915_READ(CDCLK_CTL);
+	int freq = dev_priv->skl_boot_cdclk;
+
+	/* Is PLL enabled and locked ? */
+	if (!((lcpll1 & LCPLL_PLL_ENABLE) && (lcpll1 & LCPLL_PLL_LOCK)))
+		goto sanitize;
+
+	/* DPLL okay; verify the cdclock
+	 *
+	 * Noticed in some instances that the freq selection is correct but
+	 * decimal part is programmed wrong from BIOS where pre-os does not
+	 * enable display. Verify the same as well.
+	 */
+	if (cdctl == ((cdctl & CDCLK_FREQ_SEL_MASK) | skl_cdclk_decimal(freq)))
+		/* All well; nothing to sanitize */
+		return false;
+sanitize:
+	/*
+	 * As of now initialize with max cdclk till
+	 * we get dynamic cdclk support
+	 * */
+	dev_priv->skl_boot_cdclk = 675000;
+	skl_init_cdclk(dev_priv);
+
+	/* we did have to sanitize */
+	return true;
+}
+
  /* Adjust CDclk dividers to allow high res or save power if possible */
  static void valleyview_set_cdclk(struct drm_device *dev, int cdclk)
  {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 0598932..ec10e6a 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1152,6 +1152,7 @@ void broxton_ddi_phy_uninit(struct drm_device *dev);
  void bxt_enable_dc9(struct drm_i915_private *dev_priv);
  void bxt_disable_dc9(struct drm_i915_private *dev_priv);
  void skl_init_cdclk(struct drm_i915_private *dev_priv);
+int skl_sanitize_cdclk(struct drm_i915_private *dev_priv);
  void skl_uninit_cdclk(struct drm_i915_private *dev_priv);
  void intel_dp_get_m_n(struct intel_crtc *crtc,
  		      struct intel_crtc_state *pipe_config);

_______________________________________________
Intel-gfx mailing list
Intel-gfx@xxxxxxxxxxxxxxxxxxxxx
http://lists.freedesktop.org/mailman/listinfo/intel-gfx




[Index of Archives]     [Linux USB Devel]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]
  Powered by Linux