[PATCH 2/2] drm/amd/display: Disable VUpdate interrupt for DCN hardware

[sunpeng.li at amd.com]

From: Leo Li <sunpeng.li at amd.com>

[Why]

On DCN hardware, the crtc_high_irq handler makes vupdate_high_irq
handler redundant.

All the vupdate handler does is handle vblank events, and update vrr
for DCE hw (excluding VEGA, more on that later). As far as usermode is
concerned. vstartup happens close enough to vupdate on DCN that it can
be considered the "same". Handling vblank and updating vrr at vstartup
effectively replaces vupdate on DCN.

Vega is a bit special. Like DCN, the VRR registers on Vega are
double-buffered, and swapped at vupdate. But Unlike DCN, it lacks a
vstartup interrupt. This means we can't quite remove the vupdate handler
for it, since delayerd user events due to vrr are sent off there.

[How]

Remove registration of VUpdate interrupt handler for DCN. Disable
vupdate interrupt if asic family DCN, enable otherwise.

Signed-off-by: Leo Li <sunpeng.li at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 34 +++----------------
 1 file changed, 4 insertions(+), 30 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 256a23a0ec28..568df046b2fe 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -2241,34 +2241,6 @@ static int dcn10_register_irq_handlers(struct amdgpu_device *adev)
 				dm_dcn_crtc_high_irq, c_irq_params);
 	}

-	/* Use VUPDATE_NO_LOCK interrupt on DCN, which seems to correspond to
-	 * the regular VUPDATE interrupt on DCE. We want DC_IRQ_SOURCE_VUPDATEx
-	 * to trigger at end of each vblank, regardless of state of the lock,
-	 * matching DCE behaviour.
-	 */
-	for (i = DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT;
-	     i <= DCN_1_0__SRCID__OTG0_IHC_V_UPDATE_NO_LOCK_INTERRUPT + adev->mode_info.num_crtc - 1;
-	     i++) {
-		r = amdgpu_irq_add_id(adev, SOC15_IH_CLIENTID_DCE, i, &adev->vupdate_irq);
-
-		if (r) {
-			DRM_ERROR("Failed to add vupdate 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.vupdate_params[int_params.irq_source - DC_IRQ_SOURCE_VUPDATE1];
-
-		c_irq_params->adev = adev;
-		c_irq_params->irq_src = int_params.irq_source;
-
-		amdgpu_dm_irq_register_interrupt(adev, &int_params,
-				dm_vupdate_high_irq, c_irq_params);
-	}
-
 	/* Use GRPH_PFLIP interrupt */
 	for (i = DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT;
 			i <= DCN_1_0__SRCID__HUBP0_FLIP_INTERRUPT + adev->mode_info.num_crtc - 1;
@@ -4266,7 +4238,7 @@ static inline int dm_set_vblank(struct drm_crtc *crtc, bool enable)
 	struct dm_crtc_state *acrtc_state = to_dm_crtc_state(crtc->state);
 	int rc = 0;

-	if (enable) {
+	if (enable && adev->family < AMDGPU_FAMILY_AI) {
 		/* vblank irq on -> Only need vupdate irq in vrr mode */
 		if (amdgpu_dm_vrr_active(acrtc_state))
 			rc = dm_set_vupdate_irq(crtc, true);
@@ -6243,6 +6215,7 @@ static void pre_update_freesync_state_on_stream(
 static void amdgpu_dm_handle_vrr_transition(struct dm_crtc_state *old_state,
 					    struct dm_crtc_state *new_state)
 {
+	struct amdgpu_device *adev = old_state->base.crtc->dev->dev_private;
 	bool old_vrr_active = amdgpu_dm_vrr_active(old_state);
 	bool new_vrr_active = amdgpu_dm_vrr_active(new_state);

@@ -6255,7 +6228,8 @@ static void amdgpu_dm_handle_vrr_transition(struct dm_crtc_state *old_state,
 		 * We also need vupdate irq for the actual core vblank handling
 		 * at end of vblank.
 		 */
-		dm_set_vupdate_irq(new_state->base.crtc, true);
+		if (adev->family < AMDGPU_FAMILY_AI)
+			dm_set_vupdate_irq(new_state->base.crtc, true);
 		drm_crtc_vblank_get(new_state->base.crtc);
 		DRM_DEBUG_DRIVER("%s: crtc=%u VRR off->on: Get vblank ref\n",
 				 __func__, new_state->base.crtc->base.id);
--
2.23.0