From 8dec337920a708a94bd0e00badacfe1f27a6a12e Mon Sep 17 00:00:00 2001
From: Dave Stevenson <dave.stevenson@raspberrypi.com>
Date: Wed, 24 Jan 2024 16:35:11 +0000
Subject: [PATCH 0886/1085] drm/vc4: Disable overrun interrupts

We have a read-modify-write race when updating SCALER_DISPCTRL for
underrun and end-of-frame interrupts.
Ideally it would be fixed via a spinlock or similar, but that will
require a reasonable amount of study to ensure we don't get deadlocks.

The underrun reporting is only for debug, so disable it for now.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 2 +-
 drivers/gpu/drm/vc4/vc4_kms.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -868,7 +868,7 @@ static void vc4_crtc_handle_page_flip(st
 		 * the CRTC and encoder already reconfigured, leading to
 		 * underruns. This can be seen when reconfiguring the CRTC.
 		 */
-		if (vc4->gen < VC4_GEN_6)
+		if (0 && vc4->gen < VC4_GEN_6)
 			vc4_hvs_unmask_underrun(hvs, chan);
 	}
 	spin_unlock(&vc4_crtc->irq_lock);
--- a/drivers/gpu/drm/vc4/vc4_kms.c
+++ b/drivers/gpu/drm/vc4/vc4_kms.c
@@ -391,7 +391,7 @@ static void vc4_atomic_commit_tail(struc
 	if (WARN_ON(IS_ERR(new_hvs_state)))
 		return;
 
-	if (vc4->gen < VC4_GEN_6) {
+	if (0 && vc4->gen < VC4_GEN_6) {
 		struct drm_crtc_state *new_crtc_state;
 		struct drm_crtc *crtc;
 		int i;