drm/i915: Add location of the Rcomp resistor to bxt_ddi_phy_info

Use struct bxt_ddi_phy_info to hold information of where the Rcomp
resistor is located, instead of hard coding it in the init sequence.

Note that this moves the enabling of the phy with the Rcomp resistor out
of the power well enable code. That should be safe since
bxt_ddi_phy_init() is called while the power domains lock is held, and
that is the only way that function gets called, so there is no
possibility of a concurrent phy enable caused by a power domain get
call.

v2: Replace comment about lock with lockdep_assert_held()  (Imre)

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/62d209950ad48484564f3e793cf247cf62572a39.1475770848.git-series.ander.conselvan.de.oliveira@intel.com

1 files changed, 55 insertions, 17 deletions

diff --git a/drivers/gpu/drm/i915/intel_dpio_phy.c b/drivers/gpu/drm/i915/intel_dpio_phy.c
index 1b1fba16d4e9..6711e3a53f13 100644
--- a/drivers/gpu/drm/i915/intel_dpio_phy.c
+++ b/drivers/gpu/drm/i915/intel_dpio_phy.c
@@ -124,6 +124,13 @@ struct bxt_ddi_phy_info {
 	bool dual_channel;
 
 	/**
+	 * @rcomp_phy: If -1, indicates this phy has its own rcomp resistor.
+	 * Otherwise the GRC value will be copied from the phy indicated by
+	 * this field.
+	 */
+	enum dpio_phy rcomp_phy;
+
+	/**
 	 * @channel: struct containing per channel information.
 	 */
 	struct {
@@ -137,6 +144,7 @@ struct bxt_ddi_phy_info {
 static const struct bxt_ddi_phy_info bxt_ddi_phy_info[] = {
 	[DPIO_PHY0] = {
 		.dual_channel = true,
+		.rcomp_phy = DPIO_PHY1,
 
 		.channel = {
 			[DPIO_CH0] = { .port = PORT_B },
@@ -145,6 +153,7 @@ static const struct bxt_ddi_phy_info bxt_ddi_phy_info[] = {
 	},
 	[DPIO_PHY1] = {
 		.dual_channel = false,
+		.rcomp_phy = -1,
 
 		.channel = {
 			[DPIO_CH0] = { .port = PORT_A },
@@ -214,9 +223,10 @@ bool bxt_ddi_phy_is_enabled(struct drm_i915_private *dev_priv,
 		return false;
 	}
 
-	if (phy == DPIO_PHY1 &&
-	    !(I915_READ(BXT_PORT_REF_DW3(DPIO_PHY1)) & GRC_DONE)) {
-		DRM_DEBUG_DRIVER("DDI PHY 1 powered, but GRC isn't done\n");
+	if (phy_info->rcomp_phy == -1 &&
+	    !(I915_READ(BXT_PORT_REF_DW3(phy)) & GRC_DONE)) {
+		DRM_DEBUG_DRIVER("DDI PHY %d powered, but GRC isn't done\n",
+				 phy);
 
 		return false;
 	}
@@ -261,14 +271,15 @@ static void bxt_phy_wait_grc_done(struct drm_i915_private *dev_priv,
 		DRM_ERROR("timeout waiting for PHY%d GRC\n", phy);
 }
 
-void bxt_ddi_phy_init(struct drm_i915_private *dev_priv, enum dpio_phy phy)
+static void _bxt_ddi_phy_init(struct drm_i915_private *dev_priv,
+			      enum dpio_phy phy)
 {
 	const struct bxt_ddi_phy_info *phy_info = &bxt_ddi_phy_info[phy];
 	u32 val;
 
 	if (bxt_ddi_phy_is_enabled(dev_priv, phy)) {
 		/* Still read out the GRC value for state verification */
-		if (phy == DPIO_PHY0)
+		if (phy_info->rcomp_phy != -1)
 			dev_priv->bxt_phy_grc = bxt_get_grc(dev_priv, phy);
 
 		if (bxt_ddi_phy_verify_state(dev_priv, phy)) {
@@ -338,30 +349,32 @@ void bxt_ddi_phy_init(struct drm_i915_private *dev_priv, enum dpio_phy phy)
 		val |= OCL2_LDOFUSE_PWR_DIS;
 	I915_WRITE(BXT_PORT_CL1CM_DW30(phy), val);
 
-	if (phy == DPIO_PHY0) {
+	if (phy_info->rcomp_phy != -1) {
 		uint32_t grc_code;
 		/*
 		 * PHY0 isn't connected to an RCOMP resistor so copy over
 		 * the corresponding calibrated value from PHY1, and disable
 		 * the automatic calibration on PHY0.
 		 */
-		val = dev_priv->bxt_phy_grc = bxt_get_grc(dev_priv, DPIO_PHY1);
+		val = dev_priv->bxt_phy_grc = bxt_get_grc(dev_priv,
+							  phy_info->rcomp_phy);
 		grc_code = val << GRC_CODE_FAST_SHIFT |
 			   val << GRC_CODE_SLOW_SHIFT |
 			   val;
-		I915_WRITE(BXT_PORT_REF_DW6(DPIO_PHY0), grc_code);
+		I915_WRITE(BXT_PORT_REF_DW6(phy), grc_code);
 
-		val = I915_READ(BXT_PORT_REF_DW8(DPIO_PHY0));
+		val = I915_READ(BXT_PORT_REF_DW8(phy));
 		val |= GRC_DIS | GRC_RDY_OVRD;
-		I915_WRITE(BXT_PORT_REF_DW8(DPIO_PHY0), val);
+		I915_WRITE(BXT_PORT_REF_DW8(phy), val);
 	}
 
 	val = I915_READ(BXT_PHY_CTL_FAMILY(phy));
 	val |= COMMON_RESET_DIS;
 	I915_WRITE(BXT_PHY_CTL_FAMILY(phy), val);
 
-	if (phy == DPIO_PHY1)
-		bxt_phy_wait_grc_done(dev_priv, DPIO_PHY1);
+	if (phy_info->rcomp_phy == -1)
+		bxt_phy_wait_grc_done(dev_priv, phy);
+
 }
 
 void bxt_ddi_phy_uninit(struct drm_i915_private *dev_priv, enum dpio_phy phy)
@@ -377,6 +390,31 @@ void bxt_ddi_phy_uninit(struct drm_i915_private *dev_priv, enum dpio_phy phy)
 	I915_WRITE(BXT_P_CR_GT_DISP_PWRON, val);
 }
 
+void bxt_ddi_phy_init(struct drm_i915_private *dev_priv, enum dpio_phy phy)
+{
+	const struct bxt_ddi_phy_info *phy_info = &bxt_ddi_phy_info[phy];
+	enum dpio_phy rcomp_phy = phy_info->rcomp_phy;
+	bool was_enabled;
+
+	lockdep_assert_held(&dev_priv->power_domains.lock);
+
+	if (rcomp_phy != -1) {
+		was_enabled = bxt_ddi_phy_is_enabled(dev_priv, rcomp_phy);
+
+		/*
+		 * We need to copy the GRC calibration value from rcomp_phy,
+		 * so make sure it's powered up.
+		 */
+		if (!was_enabled)
+			_bxt_ddi_phy_init(dev_priv, rcomp_phy);
+	}
+
+	_bxt_ddi_phy_init(dev_priv, phy);
+
+	if (rcomp_phy != -1 && !was_enabled)
+		bxt_ddi_phy_uninit(dev_priv, phy_info->rcomp_phy);
+}
+
 static bool __printf(6, 7)
 __phy_reg_verify_state(struct drm_i915_private *dev_priv, enum dpio_phy phy,
 		       i915_reg_t reg, u32 mask, u32 expected,
@@ -443,7 +481,7 @@ bool bxt_ddi_phy_verify_state(struct drm_i915_private *dev_priv,
 	 * at least on stepping A this bit is read-only and fixed at 0.
 	 */
 
-	if (phy == DPIO_PHY0) {
+	if (phy_info->rcomp_phy != -1) {
 		u32 grc_code = dev_priv->bxt_phy_grc;
 
 		grc_code = grc_code << GRC_CODE_FAST_SHIFT |
@@ -451,12 +489,12 @@ bool bxt_ddi_phy_verify_state(struct drm_i915_private *dev_priv,
 			   grc_code;
 		mask = GRC_CODE_FAST_MASK | GRC_CODE_SLOW_MASK |
 		       GRC_CODE_NOM_MASK;
-		ok &= _CHK(BXT_PORT_REF_DW6(DPIO_PHY0), mask, grc_code,
-			    "BXT_PORT_REF_DW6(%d)", DPIO_PHY0);
+		ok &= _CHK(BXT_PORT_REF_DW6(phy), mask, grc_code,
+			    "BXT_PORT_REF_DW6(%d)", phy);
 
 		mask = GRC_DIS | GRC_RDY_OVRD;
-		ok &= _CHK(BXT_PORT_REF_DW8(DPIO_PHY0), mask, mask,
-			    "BXT_PORT_REF_DW8(%d)", DPIO_PHY0);
+		ok &= _CHK(BXT_PORT_REF_DW8(phy), mask, mask,
+			    "BXT_PORT_REF_DW8(%d)", phy);
 	}
 
 	return ok;