drm/i915: Setup DPLL/DPLLMD for DSI too on VLV/CHV

Set up DPLL and DPLL_MD even when driving DSI output on VLV/CHV. While
the DPLL isn't used to provide the clock we still need the refclock, and
it appears that the pixel repeat factor also has an effect on DSI
output. So set up eveyrhing in DPLL and DPLL_MD as we would do for
DP/HDMI/VGA, but don't actually enable the DPLL or configure the
dividers via DPIO.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1460488478-18311-2-git-send-email-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -1530,45 +1530,47 @@ static void assert_pch_ports_disabled(struct drm_i915_private *dev_priv,
 	assert_pch_hdmi_disabled(dev_priv, pipe, PCH_HDMID);
 }
 
+static void _vlv_enable_pll(struct intel_crtc *crtc,
+			    const struct intel_crtc_state *pipe_config)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum pipe pipe = crtc->pipe;
+
+	I915_WRITE(DPLL(pipe), pipe_config->dpll_hw_state.dpll);
+	POSTING_READ(DPLL(pipe));
+	udelay(150);
+
+	if (wait_for(((I915_READ(DPLL(pipe)) & DPLL_LOCK_VLV) == DPLL_LOCK_VLV), 1))
+		DRM_ERROR("DPLL %d failed to lock\n", pipe);
+}
+
 static void vlv_enable_pll(struct intel_crtc *crtc,
 			   const struct intel_crtc_state *pipe_config)
 {
-	struct drm_device *dev = crtc->base.dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum pipe pipe = crtc->pipe;
-	i915_reg_t reg = DPLL(pipe);
-	u32 dpll = pipe_config->dpll_hw_state.dpll;
 
 	assert_pipe_disabled(dev_priv, pipe);
 
 	/* PLL is protected by panel, make sure we can write it */
 	assert_panel_unlocked(dev_priv, pipe);
 
-	I915_WRITE(reg, dpll);
-	POSTING_READ(reg);
-	udelay(150);
-
-	if (wait_for(((I915_READ(reg) & DPLL_LOCK_VLV) == DPLL_LOCK_VLV), 1))
-		DRM_ERROR("DPLL %d failed to lock\n", pipe);
+	if (pipe_config->dpll_hw_state.dpll & DPLL_VCO_ENABLE)
+		_vlv_enable_pll(crtc, pipe_config);
 
 	I915_WRITE(DPLL_MD(pipe), pipe_config->dpll_hw_state.dpll_md);
 	POSTING_READ(DPLL_MD(pipe));
 }
 
-static void chv_enable_pll(struct intel_crtc *crtc,
-			   const struct intel_crtc_state *pipe_config)
+
+static void _chv_enable_pll(struct intel_crtc *crtc,
+			    const struct intel_crtc_state *pipe_config)
 {
-	struct drm_device *dev = crtc->base.dev;
-	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum pipe pipe = crtc->pipe;
 	enum dpio_channel port = vlv_pipe_to_channel(pipe);
 	u32 tmp;
 
-	assert_pipe_disabled(dev_priv, pipe);
-
-	/* PLL is protected by panel, make sure we can write it */
-	assert_panel_unlocked(dev_priv, pipe);
-
 	mutex_lock(&dev_priv->sb_lock);
 
 	/* Enable back the 10bit clock to display controller */
@@ -1589,6 +1591,21 @@ static void chv_enable_pll(struct intel_crtc *crtc,
 	/* Check PLL is locked */
 	if (wait_for(((I915_READ(DPLL(pipe)) & DPLL_LOCK_VLV) == DPLL_LOCK_VLV), 1))
 		DRM_ERROR("PLL %d failed to lock\n", pipe);
+}
+
+static void chv_enable_pll(struct intel_crtc *crtc,
+			   const struct intel_crtc_state *pipe_config)
+{
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum pipe pipe = crtc->pipe;
+
+	assert_pipe_disabled(dev_priv, pipe);
+
+	/* PLL is protected by panel, make sure we can write it */
+	assert_panel_unlocked(dev_priv, pipe);
+
+	if (pipe_config->dpll_hw_state.dpll & DPLL_VCO_ENABLE)
+		_chv_enable_pll(crtc, pipe_config);
 
 	if (pipe != PIPE_A) {
 		/*
@@ -6079,14 +6096,12 @@ static void valleyview_crtc_enable(struct drm_crtc *crtc)
 		if (encoder->pre_pll_enable)
 			encoder->pre_pll_enable(encoder);
 
-	if (!intel_crtc->config->has_dsi_encoder) {
-		if (IS_CHERRYVIEW(dev)) {
-			chv_prepare_pll(intel_crtc, intel_crtc->config);
-			chv_enable_pll(intel_crtc, intel_crtc->config);
-		} else {
-			vlv_prepare_pll(intel_crtc, intel_crtc->config);
-			vlv_enable_pll(intel_crtc, intel_crtc->config);
-		}
+	if (IS_CHERRYVIEW(dev)) {
+		chv_prepare_pll(intel_crtc, intel_crtc->config);
+		chv_enable_pll(intel_crtc, intel_crtc->config);
+	} else {
+		vlv_prepare_pll(intel_crtc, intel_crtc->config);
+		vlv_enable_pll(intel_crtc, intel_crtc->config);
 	}
 
 	for_each_encoder_on_crtc(dev, crtc, encoder)
@@ -6124,7 +6139,7 @@ static void i9xx_crtc_enable(struct drm_crtc *crtc)
 	struct intel_encoder *encoder;
 	struct intel_crtc_state *pipe_config =
 		to_intel_crtc_state(crtc->state);
-	int pipe = intel_crtc->pipe;
+	enum pipe pipe = intel_crtc->pipe;
 
 	if (WARN_ON(intel_crtc->active))
 		return;
@@ -7180,11 +7195,15 @@ static void vlv_compute_dpll(struct intel_crtc *crtc,
 			     struct intel_crtc_state *pipe_config)
 {
 	pipe_config->dpll_hw_state.dpll = DPLL_INTEGRATED_REF_CLK_VLV |
-		DPLL_REF_CLK_ENABLE_VLV | DPLL_VGA_MODE_DIS |
-		DPLL_VCO_ENABLE | DPLL_EXT_BUFFER_ENABLE_VLV;
+		DPLL_REF_CLK_ENABLE_VLV | DPLL_VGA_MODE_DIS;
 	if (crtc->pipe != PIPE_A)
 		pipe_config->dpll_hw_state.dpll |= DPLL_INTEGRATED_CRI_CLK_VLV;
 
+	/* DPLL not used with DSI, but still need the rest set up */
+	if (!intel_pipe_will_have_type(pipe_config, INTEL_OUTPUT_DSI))
+		pipe_config->dpll_hw_state.dpll |= DPLL_VCO_ENABLE |
+			DPLL_EXT_BUFFER_ENABLE_VLV;
+
 	pipe_config->dpll_hw_state.dpll_md =
 		(pipe_config->pixel_multiplier - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT;
 }
@@ -7193,11 +7212,14 @@ static void chv_compute_dpll(struct intel_crtc *crtc,
 			     struct intel_crtc_state *pipe_config)
 {
 	pipe_config->dpll_hw_state.dpll = DPLL_SSC_REF_CLK_CHV |
-		DPLL_REF_CLK_ENABLE_VLV | DPLL_VGA_MODE_DIS |
-		DPLL_VCO_ENABLE;
+		DPLL_REF_CLK_ENABLE_VLV | DPLL_VGA_MODE_DIS;
 	if (crtc->pipe != PIPE_A)
 		pipe_config->dpll_hw_state.dpll |= DPLL_INTEGRATED_CRI_CLK_VLV;
 
+	/* DPLL not used with DSI, but still need the rest set up */
+	if (!intel_pipe_will_have_type(pipe_config, INTEL_OUTPUT_DSI))
+		pipe_config->dpll_hw_state.dpll |= DPLL_VCO_ENABLE;
+
 	pipe_config->dpll_hw_state.dpll_md =
 		(pipe_config->pixel_multiplier - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT;
 }
@@ -7207,11 +7229,20 @@ static void vlv_prepare_pll(struct intel_crtc *crtc,
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe = crtc->pipe;
+	enum pipe pipe = crtc->pipe;
 	u32 mdiv;
 	u32 bestn, bestm1, bestm2, bestp1, bestp2;
 	u32 coreclk, reg_val;
 
+	/* Enable Refclk */
+	I915_WRITE(DPLL(pipe),
+		   pipe_config->dpll_hw_state.dpll &
+		   ~(DPLL_VCO_ENABLE | DPLL_EXT_BUFFER_ENABLE_VLV));
+
+	/* No need to actually set up the DPLL with DSI */
+	if ((pipe_config->dpll_hw_state.dpll & DPLL_VCO_ENABLE) == 0)
+		return;
+
 	mutex_lock(&dev_priv->sb_lock);
 
 	bestn = pipe_config->dpll.n;
@@ -7298,14 +7329,21 @@ static void chv_prepare_pll(struct intel_crtc *crtc,
 {
 	struct drm_device *dev = crtc->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	int pipe = crtc->pipe;
-	i915_reg_t dpll_reg = DPLL(crtc->pipe);
+	enum pipe pipe = crtc->pipe;
 	enum dpio_channel port = vlv_pipe_to_channel(pipe);
 	u32 loopfilter, tribuf_calcntr;
 	u32 bestn, bestm1, bestm2, bestp1, bestp2, bestm2_frac;
 	u32 dpio_val;
 	int vco;
 
+	/* Enable Refclk and SSC */
+	I915_WRITE(DPLL(pipe),
+		   pipe_config->dpll_hw_state.dpll & ~DPLL_VCO_ENABLE);
+
+	/* No need to actually set up the DPLL with DSI */
+	if ((pipe_config->dpll_hw_state.dpll & DPLL_VCO_ENABLE) == 0)
+		return;
+
 	bestn = pipe_config->dpll.n;
 	bestm2_frac = pipe_config->dpll.m2 & 0x3fffff;
 	bestm1 = pipe_config->dpll.m1;
@@ -7316,12 +7354,6 @@ static void chv_prepare_pll(struct intel_crtc *crtc,
 	dpio_val = 0;
 	loopfilter = 0;
 
-	/*
-	 * Enable Refclk and SSC
-	 */
-	I915_WRITE(dpll_reg,
-		   pipe_config->dpll_hw_state.dpll & ~DPLL_VCO_ENABLE);
-
 	mutex_lock(&dev_priv->sb_lock);
 
 	/* p1 and p2 divider */
@@ -7936,9 +7968,6 @@ static int chv_crtc_compute_clock(struct intel_crtc *crtc,
 	memset(&crtc_state->dpll_hw_state, 0,
 	       sizeof(crtc_state->dpll_hw_state));
 
-	if (crtc_state->has_dsi_encoder)
-		return 0;
-
 	if (!crtc_state->clock_set &&
 	    !chv_find_best_dpll(limit, crtc_state, crtc_state->port_clock,
 				refclk, NULL, &crtc_state->dpll)) {
@@ -7960,9 +7989,6 @@ static int vlv_crtc_compute_clock(struct intel_crtc *crtc,
 	memset(&crtc_state->dpll_hw_state, 0,
 	       sizeof(crtc_state->dpll_hw_state));
 
-	if (crtc_state->has_dsi_encoder)
-		return 0;
-
 	if (!crtc_state->clock_set &&
 	    !vlv_find_best_dpll(limit, crtc_state, crtc_state->port_clock,
 				refclk, NULL, &crtc_state->dpll)) {

drivers/gpu/drm/i915/intel_dsi.c

@@ -311,6 +311,12 @@ static bool intel_dsi_compute_config(struct intel_encoder *encoder,
 			pipe_config->cpu_transcoder = TRANSCODER_DSI_A;
 	}
 
+	/*
+	 * FIXME move the DSI PLL calc from vlv_enable_dsi_pll()
+	 * to .compute_config().
+	 */
+	pipe_config->clock_set = true;
+
 	return true;
 }
 
@@ -498,8 +504,6 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder)
 	struct drm_device *dev = encoder->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_dsi *intel_dsi = enc_to_intel_dsi(&encoder->base);
-	struct intel_crtc *intel_crtc = to_intel_crtc(encoder->base.crtc);
-	enum pipe pipe = intel_crtc->pipe;
 	enum port port;
 	u32 tmp;
 
@@ -521,19 +525,7 @@ static void intel_dsi_pre_enable(struct intel_encoder *encoder)
 	msleep(intel_dsi->panel_on_delay);
 
 	if (IS_VALLEYVIEW(dev) || IS_CHERRYVIEW(dev)) {
-		/*
-		 * Disable DPOunit clock gating, can stall pipe
-		 * and we need DPLL REFA always enabled
-		 */
-		tmp = I915_READ(DPLL(pipe));
-		tmp |= DPLL_REF_CLK_ENABLE_VLV;
-		I915_WRITE(DPLL(pipe), tmp);
-
-		/* update the hw state for DPLL */
-		intel_crtc->config->dpll_hw_state.dpll =
-				DPLL_INTEGRATED_REF_CLK_VLV |
-					DPLL_REF_CLK_ENABLE_VLV | DPLL_VGA_MODE_DIS;
-
+		/* Disable DPOunit clock gating, can stall pipe */
 		tmp = I915_READ(DSPCLK_GATE_D);
 		tmp |= DPOUNIT_CLOCK_GATE_DISABLE;
 		I915_WRITE(DSPCLK_GATE_D, tmp);
@@ -832,12 +824,6 @@ static void intel_dsi_get_config(struct intel_encoder *encoder,
 	if (IS_BROXTON(dev))
 		bxt_dsi_get_pipe_config(encoder, pipe_config);
 
-	/*
-	 * DPLL_MD is not used in case of DSI, reading will get some default value
-	 * set dpll_md = 0
-	 */
-	pipe_config->dpll_hw_state.dpll_md = 0;
-
 	pclk = intel_dsi_get_pclk(encoder, pipe_config->pipe_bpp);
 	if (!pclk)
 		return;