Initial commit

target/linux/bcm27xx/patches-6.6/950-0886-drm-vc4-Disable-overrun-interrupts.patch

@@ -0,0 +1,40 @@
+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;