drm/i915: ValleyView mode setting limits and PLL functions

Add some VLV limit structures and update the PLL code.

v2: resolve conflicts, Vijay to re-post with PLL valid checks and fixed limits
v3: re-add dpio write function
v4: squash in Vijay's fixes for the PLL limits and clean up the m/n finder

Signed-off-by: Shobhit Kumar <shobhit.kumar@intel.com>
Signed-off-by: Vijay Purushothaman <vijay.a.purushothaman@intel.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 9730162..7794c1a 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -98,6 +98,11 @@
 			   int target, int refclk, intel_clock_t *match_clock,
 			   intel_clock_t *best_clock);
 
+static bool
+intel_vlv_find_best_pll(const intel_limit_t *limit, struct drm_crtc *crtc,
+			int target, int refclk, intel_clock_t *match_clock,
+			intel_clock_t *best_clock);
+
 static inline u32 /* units of 100MHz */
 intel_fdi_link_freq(struct drm_device *dev)
 {
@@ -359,6 +364,48 @@
 	.find_pll = intel_find_pll_ironlake_dp,
 };
 
+static const intel_limit_t intel_limits_vlv_dac = {
+	.dot = { .min = 25000, .max = 270000 },
+	.vco = { .min = 4000000, .max = 6000000 },
+	.n = { .min = 1, .max = 7 },
+	.m = { .min = 22, .max = 450 }, /* guess */
+	.m1 = { .min = 2, .max = 3 },
+	.m2 = { .min = 11, .max = 156 },
+	.p = { .min = 10, .max = 30 },
+	.p1 = { .min = 2, .max = 3 },
+	.p2 = { .dot_limit = 270000,
+		.p2_slow = 2, .p2_fast = 20 },
+	.find_pll = intel_vlv_find_best_pll,
+};
+
+static const intel_limit_t intel_limits_vlv_hdmi = {
+	.dot = { .min = 20000, .max = 165000 },
+	.vco = { .min = 5994000, .max = 4000000 },
+	.n = { .min = 1, .max = 7 },
+	.m = { .min = 60, .max = 300 }, /* guess */
+	.m1 = { .min = 2, .max = 3 },
+	.m2 = { .min = 11, .max = 156 },
+	.p = { .min = 10, .max = 30 },
+	.p1 = { .min = 2, .max = 3 },
+	.p2 = { .dot_limit = 270000,
+		.p2_slow = 2, .p2_fast = 20 },
+	.find_pll = intel_vlv_find_best_pll,
+};
+
+static const intel_limit_t intel_limits_vlv_dp = {
+	.dot = { .min = 162000, .max = 270000 },
+	.vco = { .min = 5994000, .max = 4000000 },
+	.n = { .min = 1, .max = 7 },
+	.m = { .min = 60, .max = 300 }, /* guess */
+	.m1 = { .min = 2, .max = 3 },
+	.m2 = { .min = 11, .max = 156 },
+	.p = { .min = 10, .max = 30 },
+	.p1 = { .min = 2, .max = 3 },
+	.p2 = { .dot_limit = 270000,
+		.p2_slow = 2, .p2_fast = 20 },
+	.find_pll = intel_vlv_find_best_pll,
+};
+
 u32 intel_dpio_read(struct drm_i915_private *dev_priv, int reg)
 {
 	unsigned long flags;
@@ -384,6 +431,28 @@
 	return val;
 }
 
+static void intel_dpio_write(struct drm_i915_private *dev_priv, int reg,
+			     u32 val)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev_priv->dpio_lock, flags);
+	if (wait_for_atomic_us((I915_READ(DPIO_PKT) & DPIO_BUSY) == 0, 100)) {
+		DRM_ERROR("DPIO idle wait timed out\n");
+		goto out_unlock;
+	}
+
+	I915_WRITE(DPIO_DATA, val);
+	I915_WRITE(DPIO_REG, reg);
+	I915_WRITE(DPIO_PKT, DPIO_RID | DPIO_OP_WRITE | DPIO_PORTID |
+		   DPIO_BYTE);
+	if (wait_for_atomic_us((I915_READ(DPIO_PKT) & DPIO_BUSY) == 0, 100))
+		DRM_ERROR("DPIO write wait timed out\n");
+
+out_unlock:
+       spin_unlock_irqrestore(&dev_priv->dpio_lock, flags);
+}
+
 static void vlv_init_dpio(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -510,6 +579,13 @@
 			limit = &intel_limits_pineview_lvds;
 		else
 			limit = &intel_limits_pineview_sdvo;
+	} else if (IS_VALLEYVIEW(dev)) {
+		if (intel_pipe_has_type(crtc, INTEL_OUTPUT_ANALOG))
+			limit = &intel_limits_vlv_dac;
+		else if (intel_pipe_has_type(crtc, INTEL_OUTPUT_HDMI))
+			limit = &intel_limits_vlv_hdmi;
+		else
+			limit = &intel_limits_vlv_dp;
 	} else if (!IS_GEN2(dev)) {
 		if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS))
 			limit = &intel_limits_i9xx_lvds;
@@ -783,6 +859,73 @@
 	memcpy(best_clock, &clock, sizeof(intel_clock_t));
 	return true;
 }
+static bool
+intel_vlv_find_best_pll(const intel_limit_t *limit, struct drm_crtc *crtc,
+			int target, int refclk, intel_clock_t *match_clock,
+			intel_clock_t *best_clock)
+{
+	u32 p1, p2, m1, m2, vco, bestn, bestm1, bestm2, bestp1, bestp2;
+	u32 m, n, fastclk;
+	u32 updrate, minupdate, fracbits, p;
+	unsigned long bestppm, ppm, absppm;
+	int dotclk, flag;
+
+	dotclk = target * 1000;
+	bestppm = 1000000;
+	ppm = absppm = 0;
+	fastclk = dotclk / (2*100);
+	updrate = 0;
+	minupdate = 19200;
+	fracbits = 1;
+	n = p = p1 = p2 = m = m1 = m2 = vco = bestn = 0;
+	bestm1 = bestm2 = bestp1 = bestp2 = 0;
+
+	/* based on hardware requirement, prefer smaller n to precision */
+	for (n = limit->n.min; n <= ((refclk) / minupdate); n++) {
+		updrate = refclk / n;
+		for (p1 = limit->p1.max; p1 > limit->p1.min; p1--) {
+			for (p2 = limit->p2.p2_fast+1; p2 > 0; p2--) {
+				if (p2 > 10)
+					p2 = p2 - 1;
+				p = p1 * p2;
+				/* based on hardware requirement, prefer bigger m1,m2 values */
+				for (m1 = limit->m1.min; m1 <= limit->m1.max; m1++) {
+					m2 = (((2*(fastclk * p * n / m1 )) +
+					       refclk) / (2*refclk));
+					m = m1 * m2;
+					vco = updrate * m;
+					if (vco >= limit->vco.min && vco < limit->vco.max) {
+						ppm = 1000000 * ((vco / p) - fastclk) / fastclk;
+						absppm = (ppm > 0) ? ppm : (-ppm);
+						if (absppm < 100 && ((p1 * p2) > (bestp1 * bestp2))) {
+							bestppm = 0;
+							flag = 1;
+						}
+						if (absppm < bestppm - 10) {
+							bestppm = absppm;
+							flag = 1;
+						}
+						if (flag) {
+							bestn = n;
+							bestm1 = m1;
+							bestm2 = m2;
+							bestp1 = p1;
+							bestp2 = p2;
+							flag = 0;
+						}
+					}
+				}
+			}
+		}
+	}
+	best_clock->n = bestn;
+	best_clock->m1 = bestm1;
+	best_clock->m2 = bestm2;
+	best_clock->p1 = bestp1;
+	best_clock->p2 = bestp2;
+
+	return true;
+}
 
 static void ironlake_wait_for_vblank(struct drm_device *dev, int pipe)
 {
@@ -1293,7 +1436,7 @@
 	u32 val;
 
 	/* No really, not for ILK+ */
-	BUG_ON(dev_priv->info->gen >= 5);
+	BUG_ON(!IS_VALLEYVIEW(dev_priv->dev) && dev_priv->info->gen >= 5);
 
 	/* PLL is protected by panel, make sure we can write it */
 	if (IS_MOBILE(dev_priv->dev) && !IS_I830(dev_priv->dev))
@@ -3672,13 +3815,37 @@
 	return display_bpc != bpc;
 }
 
+static int vlv_get_refclk(struct drm_crtc *crtc)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int refclk = 27000; /* for DP & HDMI */
+
+	return 100000; /* only one validated so far */
+
+	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_ANALOG)) {
+		refclk = 96000;
+	} else if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS)) {
+		if (intel_panel_use_ssc(dev_priv))
+			refclk = 100000;
+		else
+			refclk = 96000;
+	} else if (intel_pipe_has_type(crtc, INTEL_OUTPUT_EDP)) {
+		refclk = 100000;
+	}
+
+	return refclk;
+}
+
 static int i9xx_get_refclk(struct drm_crtc *crtc, int num_connectors)
 {
 	struct drm_device *dev = crtc->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int refclk;
 
-	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS) &&
+	if (IS_VALLEYVIEW(dev)) {
+		refclk = vlv_get_refclk(crtc);
+	} else if (intel_pipe_has_type(crtc, INTEL_OUTPUT_LVDS) &&
 	    intel_panel_use_ssc(dev_priv) && num_connectors < 2) {
 		refclk = dev_priv->lvds_ssc_freq * 1000;
 		DRM_DEBUG_KMS("using SSC reference clock of %d MHz\n",
@@ -3793,6 +3960,72 @@
 	I915_WRITE(LVDS, temp);
 }
 
+static void vlv_update_pll(struct drm_crtc *crtc,
+			   struct drm_display_mode *mode,
+			   struct drm_display_mode *adjusted_mode,
+			   intel_clock_t *clock, intel_clock_t *reduced_clock,
+			   int refclk, int num_connectors)
+{
+	struct drm_device *dev = crtc->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+	int pipe = intel_crtc->pipe;
+	u32 dpll, mdiv, pdiv;
+	u32 bestn, bestm1, bestm2, bestp1, bestp2;
+	bool is_hdmi;
+
+	is_hdmi = intel_pipe_has_type(crtc, INTEL_OUTPUT_HDMI);
+
+	bestn = clock->n;
+	bestm1 = clock->m1;
+	bestm2 = clock->m2;
+	bestp1 = clock->p1;
+	bestp2 = clock->p2;
+
+	/* Enable DPIO clock input */
+	dpll = DPLL_EXT_BUFFER_ENABLE_VLV | DPLL_REFA_CLK_ENABLE_VLV |
+		DPLL_VGA_MODE_DIS | DPLL_INTEGRATED_CLOCK_VLV;
+	I915_WRITE(DPLL(pipe), dpll);
+	POSTING_READ(DPLL(pipe));
+
+	mdiv = ((bestm1 << DPIO_M1DIV_SHIFT) | (bestm2 & DPIO_M2DIV_MASK));
+	mdiv |= ((bestp1 << DPIO_P1_SHIFT) | (bestp2 << DPIO_P2_SHIFT));
+	mdiv |= ((bestn << DPIO_N_SHIFT));
+	mdiv |= (1 << DPIO_POST_DIV_SHIFT);
+	mdiv |= (1 << DPIO_K_SHIFT);
+	mdiv |= DPIO_ENABLE_CALIBRATION;
+	intel_dpio_write(dev_priv, DPIO_DIV(pipe), mdiv);
+
+	intel_dpio_write(dev_priv, DPIO_CORE_CLK(pipe), 0x01000000);
+
+	pdiv = DPIO_REFSEL_OVERRIDE | (5 << DPIO_PLL_MODESEL_SHIFT) |
+		(3 << DPIO_BIAS_CURRENT_CTL_SHIFT) | (1<<20) |
+		(8 << DPIO_DRIVER_CTL_SHIFT) | (5 << DPIO_CLK_BIAS_CTL_SHIFT);
+	intel_dpio_write(dev_priv, DPIO_REFSFR(pipe), pdiv);
+
+	intel_dpio_write(dev_priv, DPIO_LFP_COEFF(pipe), 0x009f0051);
+
+	dpll |= DPLL_VCO_ENABLE;
+	I915_WRITE(DPLL(pipe), dpll);
+	POSTING_READ(DPLL(pipe));
+	if (wait_for(((I915_READ(DPLL(pipe)) & DPLL_LOCK_VLV) == DPLL_LOCK_VLV), 1))
+		DRM_ERROR("DPLL %d failed to lock\n", pipe);
+
+	if (is_hdmi) {
+		u32 temp = intel_mode_get_pixel_multiplier(adjusted_mode);
+
+		if (temp > 1)
+			temp = (temp - 1) << DPLL_MD_UDI_MULTIPLIER_SHIFT;
+		else
+			temp = 0;
+
+		I915_WRITE(DPLL_MD(pipe), temp);
+		POSTING_READ(DPLL_MD(pipe));
+	}
+
+	intel_dpio_write(dev_priv, DPIO_FASTCLK_DISABLE, 0x641); /* ??? */
+}
+
 static void i9xx_update_pll(struct drm_crtc *crtc,
 			    struct drm_display_mode *mode,
 			    struct drm_display_mode *adjusted_mode,
@@ -4050,6 +4283,9 @@
 
 	if (IS_GEN2(dev))
 		i8xx_update_pll(crtc, adjusted_mode, &clock, num_connectors);
+	else if (IS_VALLEYVIEW(dev))
+		vlv_update_pll(crtc, mode,adjusted_mode, &clock, NULL,
+			       refclk, num_connectors);
 	else
 		i9xx_update_pll(crtc, mode, adjusted_mode, &clock,
 				has_reduced_clock ? &reduced_clock : NULL,