linux-kernel - [PATCH 08/15] drm/vc4: hvs: Ignore atomic

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Message-Id: <20221207-rpi-hvs-crtc-misc-v1-8-1f8e0770798b@cerno.tech>
Date:   Wed, 07 Dec 2022 12:53:19 +0100
From:   Maxime Ripard <maxime@...no.tech>
To:     Emma Anholt <emma@...olt.net>, Maxime Ripard <mripard@...nel.org>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>, Eric Anholt <eric@...olt.net>
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        Dave Stevenson <dave.stevenson@...pberrypi.com>,
        Mateusz Kwiatkowski <kfyatek+publicgit@...il.com>,
        Maxime Ripard <maxime@...no.tech>
Subject: [PATCH 08/15] drm/vc4: hvs: Ignore atomic_flush if we're disabled

atomic_flush will be called for each CRTC even if they aren't enabled.

The whole code we have there will thus run without a properly affected
channel, which can then result in all sorts of weird behaviour.

Signed-off-by: Maxime Ripard <maxime@...no.tech>
---
 drivers/gpu/drm/vc4/vc4_hvs.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/vc4/vc4_hvs.c b/drivers/gpu/drm/vc4/vc4_hvs.c
index 3582ede1a0aa..5fadbf219542 100644
--- a/drivers/gpu/drm/vc4/vc4_hvs.c
+++ b/drivers/gpu/drm/vc4/vc4_hvs.c
@@ -579,6 +579,9 @@ void vc4_hvs_atomic_flush(struct drm_crtc *crtc,
 		return;
 	}
 
+	if (vc4_state->assigned_channel == VC4_HVS_CHANNEL_DISABLED)
+		return;
+
 	if (debug_dump_regs) {
 		DRM_INFO("CRTC %d HVS before:\n", drm_crtc_index(crtc));
 		vc4_hvs_dump_state(hvs);

-- 
2.38.1