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 <[e-mail]>
Reviewed-by: Alex Deucher <[e-mail]>
Signed-off-by: Alex Deucher <[e-mail]>

drivers/gpu/drm/amd/amdgpu/amdgpu.h

···
 struct amdgpu_ih_funcs {
 	/* ring read/write ptr handling, called from interrupt context */
 	u32 (*get_wptr)(struct amdgpu_device *adev);
+	bool (*prescreen_iv)(struct amdgpu_device *adev);
 	void (*decode_iv)(struct amdgpu_device *adev,
 			  struct amdgpu_iv_entry *entry);
 	void (*set_rptr)(struct amdgpu_device *adev);
···
 #define amdgpu_ring_init_cond_exec(r) (r)->funcs->init_cond_exec((r))
 #define amdgpu_ring_patch_cond_exec(r,o) (r)->funcs->patch_cond_exec((r),(o))
 #define amdgpu_ih_get_wptr(adev) (adev)->irq.ih_funcs->get_wptr((adev))
+#define amdgpu_ih_prescreen_iv(adev) (adev)->irq.ih_funcs->prescreen_iv((adev))
 #define amdgpu_ih_decode_iv(adev, iv) (adev)->irq.ih_funcs->decode_iv((adev), (iv))
 #define amdgpu_ih_set_rptr(adev) (adev)->irq.ih_funcs->set_rptr((adev))
 #define amdgpu_display_vblank_get_counter(adev, crtc) (adev)->mode_info.funcs->vblank_get_counter((adev), (crtc))

drivers/gpu/drm/amd/amdgpu/amdgpu_ih.c

···
 	while (adev->irq.ih.rptr != wptr) {
 		u32 ring_index = adev->irq.ih.rptr >> 2;
 
+		/* Prescreening of high-frequency interrupts */
+		if (!amdgpu_ih_prescreen_iv(adev)) {
+			adev->irq.ih.rptr &= adev->irq.ih.ptr_mask;
+			continue;
+		}
+
 		/* Before dispatching irq to IP blocks, send it to amdkfd */
 		amdgpu_amdkfd_interrupt(adev,
 				(const void *) &adev->irq.ih.ring[ring_index]);

drivers/gpu/drm/amd/amdgpu/cik_ih.c

···
  * [127:96] - reserved
  */
 
+/**
+ * cik_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool cik_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* Process all interrupts */
+	return true;
+}
+
  /**
  * cik_ih_decode_iv - decode an interrupt vector
  *
···
 
 static const struct amdgpu_ih_funcs cik_ih_funcs = {
 	.get_wptr = cik_ih_get_wptr,
+	.prescreen_iv = cik_ih_prescreen_iv,
 	.decode_iv = cik_ih_decode_iv,
 	.set_rptr = cik_ih_set_rptr
 };

drivers/gpu/drm/amd/amdgpu/cz_ih.c

···
 }
 
 /**
+ * cz_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool cz_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* Process all interrupts */
+	return true;
+}
+
+/**
  * cz_ih_decode_iv - decode an interrupt vector
  *
  * @adev: amdgpu_device pointer
···
 
 static const struct amdgpu_ih_funcs cz_ih_funcs = {
 	.get_wptr = cz_ih_get_wptr,
+	.prescreen_iv = cz_ih_prescreen_iv,
 	.decode_iv = cz_ih_decode_iv,
 	.set_rptr = cz_ih_set_rptr
 };

drivers/gpu/drm/amd/amdgpu/iceland_ih.c

···
 }
 
 /**
+ * iceland_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool iceland_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* Process all interrupts */
+	return true;
+}
+
+/**
  * iceland_ih_decode_iv - decode an interrupt vector
  *
  * @adev: amdgpu_device pointer
···
 
 static const struct amdgpu_ih_funcs iceland_ih_funcs = {
 	.get_wptr = iceland_ih_get_wptr,
+	.prescreen_iv = iceland_ih_prescreen_iv,
 	.decode_iv = iceland_ih_decode_iv,
 	.set_rptr = iceland_ih_set_rptr
 };

drivers/gpu/drm/amd/amdgpu/si_ih.c

···
 	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)
 {
···
 
 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
 };

drivers/gpu/drm/amd/amdgpu/tonga_ih.c

···
 }
 
 /**
+ * tonga_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool tonga_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* Process all interrupts */
+	return true;
+}
+
+/**
  * tonga_ih_decode_iv - decode an interrupt vector
  *
  * @adev: amdgpu_device pointer
···
 
 static const struct amdgpu_ih_funcs tonga_ih_funcs = {
 	.get_wptr = tonga_ih_get_wptr,
+	.prescreen_iv = tonga_ih_prescreen_iv,
 	.decode_iv = tonga_ih_decode_iv,
 	.set_rptr = tonga_ih_set_rptr
 };

drivers/gpu/drm/amd/amdgpu/vega10_ih.c

···
 }
 
 /**
+ * vega10_ih_prescreen_iv - prescreen an interrupt vector
+ *
+ * @adev: amdgpu_device pointer
+ *
+ * Returns true if the interrupt vector should be further processed.
+ */
+static bool vega10_ih_prescreen_iv(struct amdgpu_device *adev)
+{
+	/* TODO: Filter known pending page faults */
+	return true;
+}
+
+/**
  * vega10_ih_decode_iv - decode an interrupt vector
  *
  * @adev: amdgpu_device pointer
···
 
 static const struct amdgpu_ih_funcs vega10_ih_funcs = {
 	.get_wptr = vega10_ih_get_wptr,
+	.prescreen_iv = vega10_ih_prescreen_iv,
 	.decode_iv = vega10_ih_decode_iv,
 	.set_rptr = vega10_ih_set_rptr
 };