drm/amd/display: amdgpu_dm: add SI support (v4)

[Why]
amdgpu_dm.c requires changes for SI chipsets init and irq handlers registration

[How]
SI support: load_dmcu_fw(), amdgpu_dm_initialize_drm_device(), dm_early_init()
Add DCE6 specific dce60_register_irq_handlers() function

(v1) NOTE: As per Kaveri and older amdgpu.dc=1 kernel cmdline is required

(v2) fix for bc011f9 ("drm/amdgpu: Change SI/CI gfx/sdma/smu init sequence")
     remove CHIP_HAINAN support since it does not have physical DCE6 module

(v3) fix vblank irq support for DCE6 using ad hoc dce60_register_irq_handlers()
     replicating for vblank irq the behavior of dce110_register_irq_handlers()
     as per commit b57de80 ("drm/amd/display: Register on VLBLANK ISR.")

(v4) updated due to following kernel 5.2 commit:
     b2fddb1 ("drm/amd/display: Drop underlay plane support")

Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mauro Rossi <issor.oruam@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -1066,6 +1066,12 @@ static int load_dmcu_fw(struct amdgpu_device *adev)
 	const struct dmcu_firmware_header_v1_0 *hdr;
 
 	switch(adev->asic_type) {
+#if defined(CONFIG_DRM_AMD_DC_SI)
+	case CHIP_TAHITI:
+	case CHIP_PITCAIRN:
+	case CHIP_VERDE:
+	case CHIP_OLAND:
+#endif
 	case CHIP_BONAIRE:
 	case CHIP_HAWAII:
 	case CHIP_KAVERI:
@@ -2473,6 +2479,89 @@ static void register_hpd_handlers(struct amdgpu_device *adev)
 	}
 }
 
+#if defined(CONFIG_DRM_AMD_DC_SI)
+/* Register IRQ sources and initialize IRQ callbacks */
+static int dce60_register_irq_handlers(struct amdgpu_device *adev)
+{
+	struct dc *dc = adev->dm.dc;
+	struct common_irq_params *c_irq_params;
+	struct dc_interrupt_params int_params = {0};
+	int r;
+	int i;
+	unsigned client_id = AMDGPU_IRQ_CLIENTID_LEGACY;
+
+	int_params.requested_polarity = INTERRUPT_POLARITY_DEFAULT;
+	int_params.current_polarity = INTERRUPT_POLARITY_DEFAULT;
+
+	/*
+	 * Actions of amdgpu_irq_add_id():
+	 * 1. Register a set() function with base driver.
+	 *    Base driver will call set() function to enable/disable an
+	 *    interrupt in DC hardware.
+	 * 2. Register amdgpu_dm_irq_handler().
+	 *    Base driver will call amdgpu_dm_irq_handler() for ALL interrupts
+	 *    coming from DC hardware.
+	 *    amdgpu_dm_irq_handler() will re-direct the interrupt to DC
+	 *    for acknowledging and handling. */
+
+	/* Use VBLANK interrupt */
+	for (i = 0; i < adev->mode_info.num_crtc; i++) {
+		r = amdgpu_irq_add_id(adev, client_id, i+1 , &adev->crtc_irq);
+		if (r) {
+			DRM_ERROR("Failed to add crtc irq id!\n");
+			return r;
+		}
+
+		int_params.int_context = INTERRUPT_HIGH_IRQ_CONTEXT;
+		int_params.irq_source =
+			dc_interrupt_to_irq_source(dc, i+1 , 0);
+
+		c_irq_params = &adev->dm.vblank_params[int_params.irq_source - DC_IRQ_SOURCE_VBLANK1];
+
+		c_irq_params->adev = adev;
+		c_irq_params->irq_src = int_params.irq_source;
+
+		amdgpu_dm_irq_register_interrupt(adev, &int_params,
+				dm_crtc_high_irq, c_irq_params);
+	}
+
+	/* Use GRPH_PFLIP interrupt */
+	for (i = VISLANDS30_IV_SRCID_D1_GRPH_PFLIP;
+			i <= VISLANDS30_IV_SRCID_D6_GRPH_PFLIP; i += 2) {
+		r = amdgpu_irq_add_id(adev, client_id, i, &adev->pageflip_irq);
+		if (r) {
+			DRM_ERROR("Failed to add page flip irq id!\n");
+			return r;
+		}
+
+		int_params.int_context = INTERRUPT_HIGH_IRQ_CONTEXT;
+		int_params.irq_source =
+			dc_interrupt_to_irq_source(dc, i, 0);
+
+		c_irq_params = &adev->dm.pflip_params[int_params.irq_source - DC_IRQ_SOURCE_PFLIP_FIRST];
+
+		c_irq_params->adev = adev;
+		c_irq_params->irq_src = int_params.irq_source;
+
+		amdgpu_dm_irq_register_interrupt(adev, &int_params,
+				dm_pflip_high_irq, c_irq_params);
+
+	}
+
+	/* HPD */
+	r = amdgpu_irq_add_id(adev, client_id,
+			VISLANDS30_IV_SRCID_HOTPLUG_DETECT_A, &adev->hpd_irq);
+	if (r) {
+		DRM_ERROR("Failed to add hpd irq id!\n");
+		return r;
+	}
+
+	register_hpd_handlers(adev);
+
+	return 0;
+}
+#endif
+
 /* Register IRQ sources and initialize IRQ callbacks */
 static int dce110_register_irq_handlers(struct amdgpu_device *adev)
 {
@@ -3204,6 +3293,17 @@ static int amdgpu_dm_initialize_drm_device(struct amdgpu_device *adev)
 
 	/* Software is initialized. Now we can register interrupt handlers. */
 	switch (adev->asic_type) {
+#if defined(CONFIG_DRM_AMD_DC_SI)
+	case CHIP_TAHITI:
+	case CHIP_PITCAIRN:
+	case CHIP_VERDE:
+	case CHIP_OLAND:
+		if (dce60_register_irq_handlers(dm->adev)) {
+			DRM_ERROR("DM: Failed to initialize IRQ\n");
+			goto fail;
+		}
+		break;
+#endif
 	case CHIP_BONAIRE:
 	case CHIP_HAWAII:
 	case CHIP_KAVERI:
@@ -3328,6 +3428,20 @@ static int dm_early_init(void *handle)
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
 
 	switch (adev->asic_type) {
+#if defined(CONFIG_DRM_AMD_DC_SI)
+	case CHIP_TAHITI:
+	case CHIP_PITCAIRN:
+	case CHIP_VERDE:
+		adev->mode_info.num_crtc = 6;
+		adev->mode_info.num_hpd = 6;
+		adev->mode_info.num_dig = 6;
+		break;
+	case CHIP_OLAND:
+		adev->mode_info.num_crtc = 2;
+		adev->mode_info.num_hpd = 2;
+		adev->mode_info.num_dig = 2;
+		break;
+#endif
 	case CHIP_BONAIRE:
 	case CHIP_HAWAII:
 		adev->mode_info.num_crtc = 6;