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From 7fabf8c63a8a1a0b553581b6d28631be6c23dd85 Mon Sep 17 00:00:00 2001
From: Brian Norris <briannorris@chromium.org>
Date: Fri, 8 Oct 2021 15:31:04 -0700
Subject: drm/rockchip: vop: Add timeout for DSP hold
Git-commit: 085af7d28897deb08a4f64a29e55525f963cc041
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

If hardware is malfunctioning (e.g., misconfigured clocks?), we can get
stuck here forever, holding various DRM locks and eventually locking up
the entire system. It's better to complain loudly and move on, than to
lock up the system.

In local tests, this operation takes less than 20ms.

Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20211008153102.1.I2a5dbaaada35023a9703a8db7af501528fbb6e31@changeid
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/rockchip/rockchip_drm_vop.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
index a25b98b7f5bd..3e8d9e2d1b67 100644
--- a/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
+++ b/drivers/gpu/drm/rockchip/rockchip_drm_vop.c
@@ -726,7 +726,9 @@ static void vop_crtc_atomic_disable(struct drm_crtc *crtc,
 
 	spin_unlock(&vop->reg_lock);
 
-	wait_for_completion(&vop->dsp_hold_completion);
+	if (!wait_for_completion_timeout(&vop->dsp_hold_completion,
+					 msecs_to_jiffies(200)))
+		WARN(1, "%s: timed out waiting for DSP hold", crtc->name);
 
 	vop_dsp_hold_valid_irq_disable(vop);
 
-- 
2.38.1