| Message ID | 20241011225906.3789965-2-adrian.larumbe@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] drm/panthor: Fix runtime suspend sequence after OPP transition error | expand |
On Fri, 11 Oct 2024 23:57:00 +0100 Adrián Larumbe <adrian.larumbe@collabora.com> wrote: > When the device's runtime PM suspend callback is invoked, the switch to > a suspension OPP might sometimes fail. Although this is beyond the > control of the Panthor driver, we can attempt suspending it more than > once as a defensive strategy. > > Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com> > --- > drivers/gpu/drm/panthor/panthor_device.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c > index cedd3cbcb47d..5430557bd0b8 100644 > --- a/drivers/gpu/drm/panthor/panthor_device.c > +++ b/drivers/gpu/drm/panthor/panthor_device.c > @@ -490,6 +490,7 @@ int panthor_device_resume(struct device *dev) > int panthor_device_suspend(struct device *dev) > { > struct panthor_device *ptdev = dev_get_drvdata(dev); > + unsigned int susp_retries; > int ret, cookie; > > if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE) > @@ -522,7 +523,12 @@ int panthor_device_suspend(struct device *dev) > drm_dev_exit(cookie); > } > > - ret = panthor_devfreq_suspend(ptdev); > + for (susp_retries = 0; susp_retries < 5; susp_retries++) { > + ret = panthor_devfreq_suspend(ptdev); > + if (!ret) > + break; > + } This retry logic should probably be moved to panthor_devfreq_suspend(), but as Liviu said, I think we need to better understand why it takes several attempts for an OPP transition to succeed. > + > if (ret) { > if (panthor_device_is_initialized(ptdev) && > drm_dev_enter(&ptdev->base, &cookie)) {
diff --git a/drivers/gpu/drm/panthor/panthor_device.c b/drivers/gpu/drm/panthor/panthor_device.c index cedd3cbcb47d..5430557bd0b8 100644 --- a/drivers/gpu/drm/panthor/panthor_device.c +++ b/drivers/gpu/drm/panthor/panthor_device.c @@ -490,6 +490,7 @@ int panthor_device_resume(struct device *dev) int panthor_device_suspend(struct device *dev) { struct panthor_device *ptdev = dev_get_drvdata(dev); + unsigned int susp_retries; int ret, cookie; if (atomic_read(&ptdev->pm.state) != PANTHOR_DEVICE_PM_STATE_ACTIVE) @@ -522,7 +523,12 @@ int panthor_device_suspend(struct device *dev) drm_dev_exit(cookie); } - ret = panthor_devfreq_suspend(ptdev); + for (susp_retries = 0; susp_retries < 5; susp_retries++) { + ret = panthor_devfreq_suspend(ptdev); + if (!ret) + break; + } + if (ret) { if (panthor_device_is_initialized(ptdev) && drm_dev_enter(&ptdev->base, &cookie)) {
When the device's runtime PM suspend callback is invoked, the switch to a suspension OPP might sometimes fail. Although this is beyond the control of the Panthor driver, we can attempt suspending it more than once as a defensive strategy. Signed-off-by: Adrián Larumbe <adrian.larumbe@collabora.com> --- drivers/gpu/drm/panthor/panthor_device.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)