drm/amdgpu: add irq domain support

Hardware blocks on the GPU like ACP generate interrupts in
the GPU interrupt controller, but are driven by a separate
driver.  Add an irq domain to the GPU driver so that
blocks like ACP can register a Linux interrupt.

Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/tonga_ih.c b/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
index 743c372..b6f7d7b 100644
--- a/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/tonga_ih.c
@@ -273,8 +273,14 @@
 static int tonga_ih_early_init(void *handle)
 {
 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+	int ret;
+
+	ret = amdgpu_irq_add_domain(adev);
+	if (ret)
+		return ret;
 
 	tonga_ih_set_interrupt_funcs(adev);
+
 	return 0;
 }
 
@@ -301,6 +307,7 @@
 
 	amdgpu_irq_fini(adev);
 	amdgpu_ih_ring_fini(adev);
+	amdgpu_irq_add_domain(adev);
 
 	return 0;
 }