[Intel-gfx] [PATCH 08/10] drm/i915: Refactor LPT-H VGA dotclock disabling

[ville.syrjala at linux.intel.com]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Extract the LPT-H VGA dotclock disable to a separate function in
anticipation of further use.

While at it move the sb_lock locking inwards when enabling the VGA
dotclock, as it's only needed to protect the sideband accesses.

Also toss out the PIXCLK_GATE_GATE nop define and just use 0.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/i915_reg.h      |  1 -
 drivers/gpu/drm/i915/intel_display.c | 34 ++++++++++++++++++++--------------
 2 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index fcc819f400a6..3a9819735833 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7342,7 +7342,6 @@ enum skl_disp_power_wells {
 /* LPT PIXCLK_GATE */
 #define PIXCLK_GATE			_MMIO(0xC6020)
 #define  PIXCLK_GATE_UNGATE		(1<<0)
-#define  PIXCLK_GATE_GATE		(0<<0)
 
 /* SPLL */
 #define SPLL_CTL			_MMIO(0x46020)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 1dc125b6dcdc..322a35c67870 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -3938,6 +3938,21 @@ static int intel_crtc_wait_for_pending_flips(struct drm_crtc *crtc)
 	return 0;
 }
 
+static void lpt_disable_iclkip(struct drm_i915_private *dev_priv)
+{
+	u32 temp;
+
+	I915_WRITE(PIXCLK_GATE, 0);
+
+	mutex_lock(&dev_priv->sb_lock);
+
+	temp = intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK);
+	temp |= SBI_SSCCTL_DISABLE;
+	intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK);
+
+	mutex_unlock(&dev_priv->sb_lock);
+}
+
 /* Program iCLKIP clock to the desired frequency */
 static void lpt_program_iclkip(struct drm_crtc *crtc)
 {
@@ -3947,18 +3962,7 @@ static void lpt_program_iclkip(struct drm_crtc *crtc)
 	u32 divsel, phaseinc, auxdiv, phasedir = 0;
 	u32 temp;
 
-	mutex_lock(&dev_priv->sb_lock);
-
-	/* It is necessary to ungate the pixclk gate prior to programming
-	 * the divisors, and gate it back when it is done.
-	 */
-	I915_WRITE(PIXCLK_GATE, PIXCLK_GATE_GATE);
-
-	/* Disable SSCCTL */
-	intel_sbi_write(dev_priv, SBI_SSCCTL6,
-			intel_sbi_read(dev_priv, SBI_SSCCTL6, SBI_ICLK) |
-				SBI_SSCCTL_DISABLE,
-			SBI_ICLK);
+	lpt_disable_iclkip(dev_priv);
 
 	/* 20MHz is a corner case which is out of range for the 7-bit divisor */
 	if (clock == 20000) {
@@ -3998,6 +4002,8 @@ static void lpt_program_iclkip(struct drm_crtc *crtc)
 			phasedir,
 			phaseinc);
 
+	mutex_lock(&dev_priv->sb_lock);
+
 	/* Program SSCDIVINTPHASE6 */
 	temp = intel_sbi_read(dev_priv, SBI_SSCDIVINTPHASE6, SBI_ICLK);
 	temp &= ~SBI_SSCDIVINTPHASE_DIVSEL_MASK;
@@ -4019,12 +4025,12 @@ static void lpt_program_iclkip(struct drm_crtc *crtc)
 	temp &= ~SBI_SSCCTL_DISABLE;
 	intel_sbi_write(dev_priv, SBI_SSCCTL6, temp, SBI_ICLK);
 
+	mutex_unlock(&dev_priv->sb_lock);
+
 	/* Wait for initialization time */
 	udelay(24);
 
 	I915_WRITE(PIXCLK_GATE, PIXCLK_GATE_UNGATE);
-
-	mutex_unlock(&dev_priv->sb_lock);
 }
 
 static void ironlake_pch_transcoder_set_timings(struct intel_crtc *crtc,
-- 
2.4.10