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_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)