drm/i915/mtl: MTL PICA hotplug detection

PICA is used for DP alt mode and TBT modes. Hotplug interruption is routed
from PICA chip to south display engine and from there to north display
engine. This patch adds functionality to enable hotplug detection for
all Type-C ports (4 ports available).

Differently from HPD in south display, PICA provides a dedicated HPD
control register for each supported port, so we loop over ports
ourselves instead of using intel_hpd_hotplug_enables() or
intel_get_hpd_pins().

BSpec: 49305, 55726, 65107, 65300
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Madhumitha Tolakanahalli Pradeep <madhumitha.tolakanahalli.pradeep@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230413212443.1504245-6-radhakrishna.sripada@intel.com

drivers/gpu/drm/i915/i915_irq.c

@@ -162,6 +162,13 @@ static const u32 hpd_gen11[HPD_NUM_PINS] = {
 	[HPD_PORT_TC6] = GEN11_TC_HOTPLUG(HPD_PORT_TC6) | GEN11_TBT_HOTPLUG(HPD_PORT_TC6),
 };
 
+static const u32 hpd_xelpdp[HPD_NUM_PINS] = {
+	[HPD_PORT_TC1] = XELPDP_TBT_HOTPLUG(HPD_PORT_TC1) | XELPDP_DP_ALT_HOTPLUG(HPD_PORT_TC1),
+	[HPD_PORT_TC2] = XELPDP_TBT_HOTPLUG(HPD_PORT_TC2) | XELPDP_DP_ALT_HOTPLUG(HPD_PORT_TC2),
+	[HPD_PORT_TC3] = XELPDP_TBT_HOTPLUG(HPD_PORT_TC3) | XELPDP_DP_ALT_HOTPLUG(HPD_PORT_TC3),
+	[HPD_PORT_TC4] = XELPDP_TBT_HOTPLUG(HPD_PORT_TC4) | XELPDP_DP_ALT_HOTPLUG(HPD_PORT_TC4),
+};
+
 static const u32 hpd_icp[HPD_NUM_PINS] = {
 	[HPD_PORT_A] = SDE_DDI_HOTPLUG_ICP(HPD_PORT_A),
 	[HPD_PORT_B] = SDE_DDI_HOTPLUG_ICP(HPD_PORT_B),
@@ -182,6 +189,15 @@ static const u32 hpd_sde_dg1[HPD_NUM_PINS] = {
 	[HPD_PORT_TC1] = SDE_TC_HOTPLUG_DG2(HPD_PORT_TC1),
 };
 
+static const u32 hpd_mtp[HPD_NUM_PINS] = {
+	[HPD_PORT_A] = SDE_DDI_HOTPLUG_ICP(HPD_PORT_A),
+	[HPD_PORT_B] = SDE_DDI_HOTPLUG_ICP(HPD_PORT_B),
+	[HPD_PORT_TC1] = SDE_TC_HOTPLUG_ICP(HPD_PORT_TC1),
+	[HPD_PORT_TC2] = SDE_TC_HOTPLUG_ICP(HPD_PORT_TC2),
+	[HPD_PORT_TC3] = SDE_TC_HOTPLUG_ICP(HPD_PORT_TC3),
+	[HPD_PORT_TC4] = SDE_TC_HOTPLUG_ICP(HPD_PORT_TC4),
+};
+
 static void intel_hpd_init_pins(struct drm_i915_private *dev_priv)
 {
 	struct intel_hotplug *hpd = &dev_priv->display.hotplug;
@@ -195,7 +211,9 @@ static void intel_hpd_init_pins(struct drm_i915_private *dev_priv)
 		return;
 	}
 
-	if (DISPLAY_VER(dev_priv) >= 11)
+	if (DISPLAY_VER(dev_priv) >= 14)
+		hpd->hpd = hpd_xelpdp;
+	else if (DISPLAY_VER(dev_priv) >= 11)
 		hpd->hpd = hpd_gen11;
 	else if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv))
 		hpd->hpd = hpd_bxt;
@@ -214,6 +232,8 @@ static void intel_hpd_init_pins(struct drm_i915_private *dev_priv)
 
 	if (INTEL_PCH_TYPE(dev_priv) >= PCH_DG1)
 		hpd->pch_hpd = hpd_sde_dg1;
+	else if (INTEL_PCH_TYPE(dev_priv) >= PCH_MTP)
+		hpd->pch_hpd = hpd_mtp;
 	else if (INTEL_PCH_TYPE(dev_priv) >= PCH_ICP)
 		hpd->pch_hpd = hpd_icp;
 	else if (HAS_PCH_CNP(dev_priv) || HAS_PCH_SPT(dev_priv))
@@ -1559,6 +1579,44 @@ static void cpt_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
 		cpt_serr_int_handler(dev_priv);
 }
 
+static void xelpdp_pica_irq_handler(struct drm_i915_private *i915, u32 iir)
+{
+	enum hpd_pin pin;
+	u32 hotplug_trigger = iir & (XELPDP_DP_ALT_HOTPLUG_MASK | XELPDP_TBT_HOTPLUG_MASK);
+	u32 trigger_aux = iir & XELPDP_AUX_TC_MASK;
+	u32 pin_mask = 0, long_mask = 0;
+
+	for (pin = HPD_PORT_TC1; pin <= HPD_PORT_TC4; pin++) {
+		u32 val;
+
+		if (!(i915->display.hotplug.hpd[pin] & hotplug_trigger))
+			continue;
+
+		pin_mask |= BIT(pin);
+
+		val = intel_de_read(i915, XELPDP_PORT_HOTPLUG_CTL(pin));
+		intel_de_write(i915, XELPDP_PORT_HOTPLUG_CTL(pin), val);
+
+		if (val & (XELPDP_DP_ALT_HPD_LONG_DETECT | XELPDP_TBT_HPD_LONG_DETECT))
+			long_mask |= BIT(pin);
+	}
+
+	if (pin_mask) {
+		drm_dbg(&i915->drm,
+			"pica hotplug event received, stat 0x%08x, pins 0x%08x, long 0x%08x\n",
+			hotplug_trigger, pin_mask, long_mask);
+
+		intel_hpd_irq_handler(i915, pin_mask, long_mask);
+	}
+
+	if (trigger_aux)
+		dp_aux_irq_handler(i915);
+
+	if (!pin_mask && !trigger_aux)
+		drm_err(&i915->drm,
+			"Unexpected DE HPD/AUX interrupt 0x%08x\n", iir);
+}
+
 static void icp_irq_handler(struct drm_i915_private *dev_priv, u32 pch_iir)
 {
 	u32 ddi_hotplug_trigger = pch_iir & SDE_DDI_HOTPLUG_MASK_ICP;
@@ -2029,6 +2087,34 @@ u32 gen8_de_pipe_underrun_mask(struct drm_i915_private *dev_priv)
 	return mask;
 }
 
+static void gen8_read_and_ack_pch_irqs(struct drm_i915_private *i915, u32 *pch_iir, u32 *pica_iir)
+{
+	u32 pica_ier = 0;
+
+	*pica_iir = 0;
+	*pch_iir = intel_de_read(i915, SDEIIR);
+	if (!*pch_iir)
+		return;
+
+	/**
+	 * PICA IER must be disabled/re-enabled around clearing PICA IIR and
+	 * SDEIIR, to avoid losing PICA IRQs and to ensure that such IRQs set
+	 * their flags both in the PICA and SDE IIR.
+	 */
+	if (*pch_iir & SDE_PICAINTERRUPT) {
+		drm_WARN_ON(&i915->drm, INTEL_PCH_TYPE(i915) < PCH_MTP);
+
+		pica_ier = intel_de_rmw(i915, PICAINTERRUPT_IER, ~0, 0);
+		*pica_iir = intel_de_read(i915, PICAINTERRUPT_IIR);
+		intel_de_write(i915, PICAINTERRUPT_IIR, *pica_iir);
+	}
+
+	intel_de_write(i915, SDEIIR, *pch_iir);
+
+	if (pica_ier)
+		intel_de_write(i915, PICAINTERRUPT_IER, pica_ier);
+}
+
 static irqreturn_t
 gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 {
@@ -2153,16 +2239,20 @@ gen8_de_irq_handler(struct drm_i915_private *dev_priv, u32 master_ctl)
 
 	if (HAS_PCH_SPLIT(dev_priv) && !HAS_PCH_NOP(dev_priv) &&
 	    master_ctl & GEN8_DE_PCH_IRQ) {
+		u32 pica_iir;
+
 		/*
 		 * FIXME(BDW): Assume for now that the new interrupt handling
 		 * scheme also closed the SDE interrupt handling race we've seen
 		 * on older pch-split platforms. But this needs testing.
 		 */
-		iir = intel_uncore_read(&dev_priv->uncore, SDEIIR);
+		gen8_read_and_ack_pch_irqs(dev_priv, &iir, &pica_iir);
 		if (iir) {
-			intel_uncore_write(&dev_priv->uncore, SDEIIR, iir);
 			ret = IRQ_HANDLED;
 
+			if (pica_iir)
+				xelpdp_pica_irq_handler(dev_priv, pica_iir);
+
 			if (INTEL_PCH_TYPE(dev_priv) >= PCH_ICP)
 				icp_irq_handler(dev_priv, iir);
 			else if (INTEL_PCH_TYPE(dev_priv) >= PCH_SPT)
@@ -2740,6 +2830,10 @@ static void gen11_display_irq_reset(struct drm_i915_private *dev_priv)
 
 	GEN3_IRQ_RESET(uncore, GEN8_DE_PORT_);
 	GEN3_IRQ_RESET(uncore, GEN8_DE_MISC_);
+
+	if (DISPLAY_VER(dev_priv) >= 14)
+		GEN3_IRQ_RESET(uncore, PICAINTERRUPT_);
+	else
 		GEN3_IRQ_RESET(uncore, GEN11_DE_HPD_);
 
 	if (INTEL_PCH_TYPE(dev_priv) >= PCH_ICP)
@@ -3031,6 +3125,116 @@ static void gen11_hpd_irq_setup(struct drm_i915_private *dev_priv)
 		icp_hpd_irq_setup(dev_priv);
 }
 
+static u32 mtp_ddi_hotplug_enables(struct intel_encoder *encoder)
+{
+	switch (encoder->hpd_pin) {
+	case HPD_PORT_A:
+	case HPD_PORT_B:
+		return SHOTPLUG_CTL_DDI_HPD_ENABLE(encoder->hpd_pin);
+	default:
+		return 0;
+	}
+}
+
+static u32 mtp_tc_hotplug_enables(struct intel_encoder *encoder)
+{
+	switch (encoder->hpd_pin) {
+	case HPD_PORT_TC1:
+	case HPD_PORT_TC2:
+	case HPD_PORT_TC3:
+	case HPD_PORT_TC4:
+		return ICP_TC_HPD_ENABLE(encoder->hpd_pin);
+	default:
+		return 0;
+	}
+}
+
+static void mtp_ddi_hpd_detection_setup(struct drm_i915_private *i915)
+{
+	intel_de_rmw(i915, SHOTPLUG_CTL_DDI,
+		     (SHOTPLUG_CTL_DDI_HPD_ENABLE(HPD_PORT_A) |
+		      SHOTPLUG_CTL_DDI_HPD_ENABLE(HPD_PORT_B)),
+		     intel_hpd_hotplug_enables(i915, mtp_ddi_hotplug_enables));
+}
+
+static void mtp_tc_hpd_detection_setup(struct drm_i915_private *i915)
+{
+	intel_de_rmw(i915, SHOTPLUG_CTL_TC,
+		     (ICP_TC_HPD_ENABLE(HPD_PORT_TC1) |
+		      ICP_TC_HPD_ENABLE(HPD_PORT_TC2) |
+		      ICP_TC_HPD_ENABLE(HPD_PORT_TC3) |
+		      ICP_TC_HPD_ENABLE(HPD_PORT_TC4)),
+		     intel_hpd_hotplug_enables(i915, mtp_tc_hotplug_enables));
+}
+
+static void mtp_hpd_invert(struct drm_i915_private *i915)
+{
+	u32 val = (INVERT_DDIA_HPD |
+		   INVERT_DDIB_HPD |
+		   INVERT_DDIC_HPD |
+		   INVERT_TC1_HPD |
+		   INVERT_TC2_HPD |
+		   INVERT_TC3_HPD |
+		   INVERT_TC4_HPD |
+		   INVERT_DDID_HPD_MTP |
+		   INVERT_DDIE_HPD);
+	intel_de_rmw(i915, SOUTH_CHICKEN1, 0, val);
+}
+
+static void mtp_hpd_irq_setup(struct drm_i915_private *i915)
+{
+	u32 hotplug_irqs, enabled_irqs;
+
+	enabled_irqs = intel_hpd_enabled_irqs(i915, i915->display.hotplug.pch_hpd);
+	hotplug_irqs = intel_hpd_hotplug_irqs(i915, i915->display.hotplug.pch_hpd);
+
+	intel_de_write(i915, SHPD_FILTER_CNT, SHPD_FILTER_CNT_500_ADJ);
+
+	mtp_hpd_invert(i915);
+	ibx_display_interrupt_update(i915, hotplug_irqs, enabled_irqs);
+
+	mtp_ddi_hpd_detection_setup(i915);
+	mtp_tc_hpd_detection_setup(i915);
+}
+
+static void xelpdp_pica_hpd_detection_setup(struct drm_i915_private *i915)
+{
+	struct intel_encoder *encoder;
+	enum hpd_pin pin;
+	u32 available_pins = 0;
+
+	BUILD_BUG_ON(BITS_PER_TYPE(available_pins) < HPD_NUM_PINS);
+
+	for_each_intel_encoder(&i915->drm, encoder)
+		available_pins |= BIT(encoder->hpd_pin);
+
+	for (pin = HPD_PORT_TC1; pin <= HPD_PORT_TC4; pin++) {
+		u32 mask = XELPDP_TBT_HOTPLUG_ENABLE |
+			   XELPDP_DP_ALT_HOTPLUG_ENABLE;
+
+		intel_de_rmw(i915, XELPDP_PORT_HOTPLUG_CTL(pin),
+			     mask,
+			     available_pins & BIT(pin) ?  mask : 0);
+	}
+}
+
+static void xelpdp_hpd_irq_setup(struct drm_i915_private *i915)
+{
+	u32 hotplug_irqs, enabled_irqs;
+
+	enabled_irqs = intel_hpd_enabled_irqs(i915, i915->display.hotplug.hpd);
+	hotplug_irqs = intel_hpd_hotplug_irqs(i915, i915->display.hotplug.hpd);
+
+	intel_de_rmw(i915, PICAINTERRUPT_IMR, hotplug_irqs,
+		     ~enabled_irqs & hotplug_irqs);
+	intel_uncore_posting_read(&i915->uncore, PICAINTERRUPT_IMR);
+
+	xelpdp_pica_hpd_detection_setup(i915);
+
+	if (INTEL_PCH_TYPE(i915) >= PCH_MTP)
+		mtp_hpd_irq_setup(i915);
+}
+
 static u32 spt_hotplug_enables(struct intel_encoder *encoder)
 {
 	switch (encoder->hpd_pin) {
@@ -3363,7 +3567,7 @@ static void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
 	GEN3_IRQ_INIT(uncore, GEN8_DE_PORT_, ~de_port_masked, de_port_enables);
 	GEN3_IRQ_INIT(uncore, GEN8_DE_MISC_, ~de_misc_masked, de_misc_masked);
 
-	if (DISPLAY_VER(dev_priv) >= 11) {
+	if (IS_DISPLAY_VER(dev_priv, 11, 13)) {
 		u32 de_hpd_masked = 0;
 		u32 de_hpd_enables = GEN11_DE_TC_HOTPLUG_MASK |
 				     GEN11_DE_TBT_HOTPLUG_MASK;
@@ -3373,6 +3577,20 @@ static void gen8_de_irq_postinstall(struct drm_i915_private *dev_priv)
 	}
 }
 
+static void mtp_irq_postinstall(struct drm_i915_private *i915)
+{
+	struct intel_uncore *uncore = &i915->uncore;
+	u32 sde_mask = SDE_GMBUS_ICP | SDE_PICAINTERRUPT;
+	u32 de_hpd_mask = XELPDP_AUX_TC_MASK;
+	u32 de_hpd_enables = de_hpd_mask | XELPDP_DP_ALT_HOTPLUG_MASK |
+			     XELPDP_TBT_HOTPLUG_MASK;
+
+	GEN3_IRQ_INIT(uncore, PICAINTERRUPT_, ~de_hpd_mask,
+		      de_hpd_enables);
+
+	GEN3_IRQ_INIT(uncore, SDE, ~sde_mask, 0xffffffff);
+}
+
 static void icp_irq_postinstall(struct drm_i915_private *dev_priv)
 {
 	struct intel_uncore *uncore = &dev_priv->uncore;
@@ -3434,7 +3652,11 @@ static void dg1_irq_postinstall(struct drm_i915_private *dev_priv)
 	GEN3_IRQ_INIT(uncore, GEN11_GU_MISC_, ~gu_misc_masked, gu_misc_masked);
 
 	if (HAS_DISPLAY(dev_priv)) {
+		if (DISPLAY_VER(dev_priv) >= 14)
+			mtp_irq_postinstall(dev_priv);
+		else
 			icp_irq_postinstall(dev_priv);
+
 		gen8_de_irq_postinstall(dev_priv);
 		intel_uncore_write(&dev_priv->uncore, GEN11_DISPLAY_INT_CTL,
 				   GEN11_DISPLAY_IRQ_ENABLE);
@@ -3920,6 +4142,7 @@ static const struct intel_hotplug_funcs platform##_hpd_funcs = { \
 }
 
 HPD_FUNCS(i915);
+HPD_FUNCS(xelpdp);
 HPD_FUNCS(dg1);
 HPD_FUNCS(gen11);
 HPD_FUNCS(bxt);
@@ -3980,6 +4203,8 @@ void intel_irq_init(struct drm_i915_private *dev_priv)
 			dev_priv->display.funcs.hotplug = &icp_hpd_funcs;
 		else if (HAS_PCH_DG1(dev_priv))
 			dev_priv->display.funcs.hotplug = &dg1_hpd_funcs;
+		else if (DISPLAY_VER(dev_priv) >= 14)
+			dev_priv->display.funcs.hotplug = &xelpdp_hpd_funcs;
 		else if (DISPLAY_VER(dev_priv) >= 11)
 			dev_priv->display.funcs.hotplug = &gen11_hpd_funcs;
 		else if (IS_GEMINILAKE(dev_priv) || IS_BROXTON(dev_priv))

drivers/gpu/drm/i915/i915_reg.h

@@ -4477,6 +4477,28 @@
 #define  GEN11_HOTPLUG_CTL_SHORT_DETECT(hpd_pin)	(1 << (_HPD_PIN_TC(hpd_pin) * 4))
 #define  GEN11_HOTPLUG_CTL_NO_DETECT(hpd_pin)		(0 << (_HPD_PIN_TC(hpd_pin) * 4))
 
+#define PICAINTERRUPT_ISR			_MMIO(0x16FE50)
+#define PICAINTERRUPT_IMR			_MMIO(0x16FE54)
+#define PICAINTERRUPT_IIR			_MMIO(0x16FE58)
+#define PICAINTERRUPT_IER			_MMIO(0x16FE5C)
+
+#define  XELPDP_DP_ALT_HOTPLUG(hpd_pin)		REG_BIT(16 + _HPD_PIN_TC(hpd_pin))
+#define  XELPDP_DP_ALT_HOTPLUG_MASK		REG_GENMASK(19, 16)
+
+#define  XELPDP_AUX_TC(hpd_pin)			REG_BIT(8 + _HPD_PIN_TC(hpd_pin))
+#define  XELPDP_AUX_TC_MASK			REG_GENMASK(11, 8)
+
+#define  XELPDP_TBT_HOTPLUG(hpd_pin)		REG_BIT(_HPD_PIN_TC(hpd_pin))
+#define  XELPDP_TBT_HOTPLUG_MASK		REG_GENMASK(3, 0)
+
+#define XELPDP_PORT_HOTPLUG_CTL(hpd_pin)	_MMIO(0x16F270 + (_HPD_PIN_TC(hpd_pin) * 0x200))
+#define  XELPDP_TBT_HOTPLUG_ENABLE		REG_BIT(6)
+#define  XELPDP_TBT_HPD_LONG_DETECT		REG_BIT(5)
+#define  XELPDP_TBT_HPD_SHORT_DETECT		REG_BIT(4)
+#define  XELPDP_DP_ALT_HOTPLUG_ENABLE		REG_BIT(2)
+#define  XELPDP_DP_ALT_HPD_LONG_DETECT		REG_BIT(1)
+#define  XELPDP_DP_ALT_HPD_SHORT_DETECT		REG_BIT(0)
+
 #define ILK_DISPLAY_CHICKEN2	_MMIO(0x42004)
 /* Required on all Ironlake and Sandybridge according to the B-Spec. */
 #define  ILK_ELPIN_409_SELECT	(1 << 25)
@@ -4762,7 +4784,8 @@
 				 SDE_FDI_RXB_CPT | \
 				 SDE_FDI_RXA_CPT)
 
-/* south display engine interrupt: ICP/TGP */
+/* south display engine interrupt: ICP/TGP/MTP */
+#define SDE_PICAINTERRUPT		REG_BIT(31)
 #define SDE_GMBUS_ICP			(1 << 23)
 #define SDE_TC_HOTPLUG_ICP(hpd_pin)	REG_BIT(24 + _HPD_PIN_TC(hpd_pin))
 #define SDE_TC_HOTPLUG_DG2(hpd_pin)	REG_BIT(25 + _HPD_PIN_TC(hpd_pin)) /* sigh */
@@ -5116,6 +5139,12 @@
 #define SOUTH_CHICKEN1		_MMIO(0xc2000)
 #define  FDIA_PHASE_SYNC_SHIFT_OVR	19
 #define  FDIA_PHASE_SYNC_SHIFT_EN	18
+#define  INVERT_DDIE_HPD			REG_BIT(28)
+#define  INVERT_DDID_HPD_MTP			REG_BIT(27)
+#define  INVERT_TC4_HPD				REG_BIT(26)
+#define  INVERT_TC3_HPD				REG_BIT(25)
+#define  INVERT_TC2_HPD				REG_BIT(24)
+#define  INVERT_TC1_HPD				REG_BIT(23)
 #define  INVERT_DDID_HPD			(1 << 18)
 #define  INVERT_DDIC_HPD			(1 << 17)
 #define  INVERT_DDIB_HPD			(1 << 16)