[PATCH 3/4] drm/v3d: Clean caches before runtime suspend

[Maíra Canal <mcanal@igalia.com>]

On runtime suspend, clean the V3D caches before suspending so all dirty
lines are written back to memory before the power domain is shut down.

Fixes several system hangs reported in [1][2][3].

Closes: https://github.com/raspberrypi/linux/issues/7381 [1]
Closes: https://github.com/raspberrypi/linux/issues/7396 [2]
Closes: https://github.com/raspberrypi/linux/issues/7397 [3]
Fixes: 458f2a712ab4 ("drm/v3d: Introduce Runtime Power Management")
Signed-off-by: Maíra Canal <mcanal@igalia.com>
---
 drivers/gpu/drm/v3d/v3d_power.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/v3d/v3d_power.c b/drivers/gpu/drm/v3d/v3d_power.c
index 769e90032b04..f7df6393d38f 100644
--- a/drivers/gpu/drm/v3d/v3d_power.c
+++ b/drivers/gpu/drm/v3d/v3d_power.c
@@ -52,6 +52,8 @@ int v3d_power_suspend(struct device *dev)
 
 	v3d_irq_disable(v3d);
 
+	v3d_clean_caches(v3d);
+
 	ret = v3d_suspend_sms(v3d);
 	if (ret) {
 		v3d_irq_enable(v3d);

-- 
2.54.0