drm/amdgpu: Add prescreening stage in IH processing (v2)

To filter out high-frequency interrupts that can be safely ignored.

v2: squash in trivial typo fix for si (Alex)

Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
diff --git a/drivers/gpu/drm/amd/amdgpu/si_ih.c b/drivers/gpu/drm/amd/amdgpu/si_ih.c
index ce25e03..d2c6b80 100644
--- a/drivers/gpu/drm/amd/amdgpu/si_ih.c
+++ b/drivers/gpu/drm/amd/amdgpu/si_ih.c
@@ -118,6 +118,19 @@ static u32 si_ih_get_wptr(struct amdgpu_device *adev)
 	return (wptr & adev->irq.ih.ptr_mask);
 }
 
+/**
+ * si_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool si_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* Process all interrupts */
+	return true;
+}
+
 static void si_ih_decode_iv(struct amdgpu_device *adev,
 			     struct amdgpu_iv_entry *entry)
 {
@@ -288,6 +301,7 @@ static const struct amd_ip_funcs si_ih_ip_funcs = {
 
 static const struct amdgpu_ih_funcs si_ih_funcs = {
 	.get_wptr = si_ih_get_wptr,
+	.prescreen_iv = si_ih_prescreen_iv,
 	.decode_iv = si_ih_decode_iv,
 	.set_rptr = si_ih_set_rptr
 };