drm/i915: Move the SPLL enabling into hsw_crt_pre_enable

The call to intel_ddi_pll_enable in haswell_crtc_mode_set is the only
function that still touches the hardware state from the crtc mode_set
callback on hsw. Since the SPLL isn't ever shared we can easily take
it out into the hsw crt encoder functions.

Temporarily we'll loose a bit of WARN_ON coverage with this, but once
the WRPLLs are switched over that will be restored. For the SPLL
selection add a WARN in the hsw fdi link training code.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
[imre: rebased on patchset version w/o pch/crt/fdi refactoring]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/intel_crt.c

@@ -137,6 +137,18 @@ static void hsw_crt_get_config(struct intel_encoder *encoder,
 	pipe_config->adjusted_mode.flags |= intel_crt_get_flags(encoder);
 }
 
+static void hsw_crt_pre_enable(struct intel_encoder *encoder)
+{
+	struct drm_device *dev = encoder->base.dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+
+	WARN(I915_READ(SPLL_CTL) & SPLL_PLL_ENABLE, "SPLL already enabled\n");
+	I915_WRITE(SPLL_CTL,
+		   SPLL_PLL_ENABLE | SPLL_PLL_FREQ_1350MHz | SPLL_PLL_SSC);
+	POSTING_READ(SPLL_CTL);
+	udelay(20);
+}
+
 /* Note: The caller is required to filter out dpms modes not supported by the
  * platform. */
 static void intel_crt_set_dpms(struct intel_encoder *encoder, int mode)
@@ -860,6 +872,7 @@ void intel_crt_init(struct drm_device *dev)
 	if (HAS_DDI(dev)) {
 		crt->base.get_config = hsw_crt_get_config;
 		crt->base.get_hw_state = intel_ddi_get_hw_state;
+		crt->base.pre_enable = hsw_crt_pre_enable;
 	} else {
 		crt->base.get_config = intel_crt_get_config;
 		crt->base.get_hw_state = intel_crt_get_hw_state;

drivers/gpu/drm/i915/intel_ddi.c

@@ -278,6 +278,7 @@ void hsw_fdi_link_train(struct drm_crtc *crtc)
 
 	/* Configure Port Clock Select */
 	I915_WRITE(PORT_CLK_SEL(PORT_E), intel_crtc->ddi_pll_sel);
+	WARN_ON(intel_crtc->ddi_pll_sel != PORT_CLK_SEL_SPLL);
 
 	/* Start the training iterating through available voltages and emphasis,
 	 * testing each value twice. */
@@ -848,23 +849,6 @@ void intel_ddi_pll_enable(struct intel_crtc *crtc)
 	BUILD_BUG_ON(enable_bit != WRPLL_PLL_ENABLE);
 
 	switch (crtc->ddi_pll_sel) {
-	case PORT_CLK_SEL_LCPLL_2700:
-	case PORT_CLK_SEL_LCPLL_1350:
-	case PORT_CLK_SEL_LCPLL_810:
-		/*
-		 * LCPLL should always be enabled at this point of the mode set
-		 * sequence, so nothing to do.
-		 */
-		return;
-
-	case PORT_CLK_SEL_SPLL:
-		new_val = SPLL_PLL_ENABLE | SPLL_PLL_FREQ_1350MHz |
-			  SPLL_PLL_SSC;
-		WARN(I915_READ(SPLL_CTL) & enable_bit, "SPLL already enabled\n");
-		I915_WRITE(SPLL_CTL, new_val);
-		POSTING_READ(SPLL_CTL);
-		udelay(20);
-		return;
 	case PORT_CLK_SEL_WRPLL1:
 	case PORT_CLK_SEL_WRPLL2:
 		if (crtc->ddi_pll_sel == PORT_CLK_SEL_WRPLL1) {
@@ -889,7 +873,6 @@ void intel_ddi_pll_enable(struct intel_crtc *crtc)
 		WARN(1, "Bad selected pll: PORT_CLK_SEL_NONE\n");
 		return;
 	default:
-		WARN(1, "Bad selected pll: 0x%08x\n", crtc->ddi_pll_sel);
 		return;
 	}