If a reset is scheduled when the suspend happens, we drop the
reset-pending info on the floor assuming the resume will fix things,
but the resume logic might try a fast reset. If we're lucky, the
fast reset fails and we fallback to a slow reset, but if the FW was
corrupted in a way that makes it partially functional (it boots but
doesn't quite do what it's expected to do), we won't notice immediately
that things are not working correctly, leading to a new reset further
down the road.
Fixes: 5fe909cae118 ("drm/panthor: Add the device logical block")
Signed-off-by: Boris Brezillon <boris.brezil...@collabora.com>
---
drivers/gpu/drm/panthor/panthor_device.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/panthor/panthor_device.c
b/drivers/gpu/drm/panthor/panthor_device.c
index 2c817e65e6be..3285ac42d2cd 100644
--- a/drivers/gpu/drm/panthor/panthor_device.c
+++ b/drivers/gpu/drm/panthor/panthor_device.c
@@ -128,14 +128,11 @@ static void panthor_device_reset_work(struct work_struct
*work)
struct panthor_device *ptdev = container_of(work, struct
panthor_device, reset.work);
int ret = 0, cookie;
- if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE) {
- /*
- * No need for a reset as the device has been (or will be)
- * powered down
- */
- atomic_set(&ptdev->reset.pending, 0);
+ /* If the device is entering suspend, we don't reset. A slow reset will
+ * be forced at resume time instead.
+ */
+ if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE)
return;
- }
if (!drm_dev_enter(&ptdev->base, &cookie))
return;
@@ -473,6 +470,14 @@ int panthor_device_resume(struct device *dev)
if (panthor_device_is_initialized(ptdev) &&
drm_dev_enter(&ptdev->base, &cookie)) {
+ /* If there was a reset pending at the time we suspended the
+ * device, we force a slow reset.
+ */
+ if (atomic_read(&ptdev->reset.pending)) {
+ ptdev->reset.fast = false;
+ atomic_set(&ptdev->reset.pending, 0);
+ }
+
ret = panthor_device_resume_hw_components(ptdev);
if (ret && ptdev->reset.fast) {
drm_err(&ptdev->base, "Fast reset failed, trying a slow
reset");
@@ -489,9 +494,6 @@ int panthor_device_resume(struct device *dev)
goto err_suspend_devfreq;
}
- if (atomic_read(&ptdev->reset.pending))
- queue_work(ptdev->reset.wq, &ptdev->reset.work);
-
/* Clear all IOMEM mappings pointing to this device after we've
* resumed. This way the fake mappings pointing to the dummy pages
* are removed and the real iomem mapping will be restored on next
--
2.47.0
