[PATCH 0/2] soundwire: improve pm_runtime handling
This patchset improves the pm_runtime behavior in rare corner cases identified by the Intel CI in the last 6 months.
a) in stress-tests, it's not uncommon to see the following type of warnings when the codec reports as ATTACHED
"rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active"
This warning was not correlated with any functional issue, but it exposed a design issue on when to enable pm_runtime. The recommended practice in the pm_runtime documentation is to keep the devices in 'suspended' mode and mark them as 'active' when they are really functional.
Pierre-Louis Bossart (2): soundwire: intel_auxdevice: enable pm_runtime earlier on startup soundWire: intel_auxdevice: resume 'sdw-master' on startup and system resume
drivers/soundwire/intel_auxdevice.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-)
From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
As soon as the bus starts, physical peripheral devices may report as ATTACHED and set their status with pm_runtime_set_active() in their update_status()/io_init().
This is problematic with the existing code, since the parent pm_runtime status is changed to "active" after starting the bus. This creates a time window where the pm_runtime framework can report an issue, e.g.
"rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active"
This patch enables runtime_pm earlier to make sure the auxiliary device is pm_runtime active after powering-up, but before starting the bus.
This problem was exposed by recent changes in the timing of the bus reset, but was present in this driver since we introduced pm_runtime support.
Closes: https://github.com/thesofproject/linux/issues/4328 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel_auxdevice.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-)
diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c index 0daa6ca9a224..f51c776eeeff 100644 --- a/drivers/soundwire/intel_auxdevice.c +++ b/drivers/soundwire/intel_auxdevice.c @@ -248,13 +248,6 @@ int intel_link_startup(struct auxiliary_device *auxdev)
sdw_intel_debugfs_init(sdw);
- /* start bus */ - ret = sdw_intel_start_bus(sdw); - if (ret) { - dev_err(dev, "bus start failed: %d\n", ret); - goto err_power_up; - } - /* Enable runtime PM */ if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) { pm_runtime_set_autosuspend_delay(dev, @@ -266,6 +259,13 @@ int intel_link_startup(struct auxiliary_device *auxdev) pm_runtime_enable(dev); }
+ /* start bus */ + ret = sdw_intel_start_bus(sdw); + if (ret) { + dev_err(dev, "bus start failed: %d\n", ret); + goto err_pm_runtime; + } + clock_stop_quirks = sdw->link_res->clock_stop_quirks; if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) { /* @@ -293,12 +293,17 @@ int intel_link_startup(struct auxiliary_device *auxdev) * with a delay. A more complete solution would require the * definition of Master properties. */ - if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) + if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) { + pm_runtime_mark_last_busy(dev); pm_runtime_idle(dev); + }
sdw->startup_done = true; return 0;
+err_pm_runtime: + if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) + pm_runtime_disable(dev); err_power_up: sdw_intel_link_power_down(sdw); err_init:
On Thu, Aug 03, 2023 at 02:52:19PM +0800, Bard Liao wrote:
From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
As soon as the bus starts, physical peripheral devices may report as ATTACHED and set their status with pm_runtime_set_active() in their update_status()/io_init().
This is problematic with the existing code, since the parent pm_runtime status is changed to "active" after starting the bus. This creates a time window where the pm_runtime framework can report an issue, e.g.
"rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active"
This patch enables runtime_pm earlier to make sure the auxiliary device is pm_runtime active after powering-up, but before starting the bus.
This problem was exposed by recent changes in the timing of the bus reset, but was present in this driver since we introduced pm_runtime support.
Closes: https://github.com/thesofproject/linux/issues/4328 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com
Doesn't seem to cause any problems on my SoundWire devices, so very loosely:
Tested-by: Charles Keepax ckeepax@opensource.cirrus.com
Thanks, Charles
From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
The SoundWire bus is handled with a dedicated device, which is placed between the Intel auxiliary device and peripheral devices, e.g.
soundwire_intel.link.0/sdw-master-0/sdw:0:025d:0711:01
The functionality of this 'sdw-master' device is limited, specifically for pm_runtime the ASoC framework will not rely on pm_runtime_get_sync() since it does not register any components. It will only change status thanks to the parent-child relationship which guarantees that the 'sdw-master' device will be pm_runtime resumed before any peripheral device.
However on startup and system resume it's possible that only the auxiliary device is pm_runtime active, and the peripheral will only become active during its io_init routine, leading to another occurrence of the error reported by the pm_runtime framework:
rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active
This patch suggests aligning the sdw-master device status to that of the auxiliary device. The difference between the two is completely notional and their pm_status shouldn't be different during the startup and system resume steps.
This problem was exposed by recent changes in the timing of the bus reset, but was present in this driver since we introduced pm_runtime support.
Closes: https://github.com/thesofproject/linux/issues/4328 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel_auxdevice.c | 6 ++++++ 1 file changed, 6 insertions(+)
diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c index f51c776eeeff..91c86b46a5a1 100644 --- a/drivers/soundwire/intel_auxdevice.c +++ b/drivers/soundwire/intel_auxdevice.c @@ -257,6 +257,8 @@ int intel_link_startup(struct auxiliary_device *auxdev)
pm_runtime_set_active(dev); pm_runtime_enable(dev); + + pm_runtime_resume(bus->dev); }
/* start bus */ @@ -294,6 +296,7 @@ int intel_link_startup(struct auxiliary_device *auxdev) * definition of Master properties. */ if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) { + pm_runtime_mark_last_busy(bus->dev); pm_runtime_mark_last_busy(dev); pm_runtime_idle(dev); } @@ -557,6 +560,8 @@ static int __maybe_unused intel_resume(struct device *dev) pm_runtime_mark_last_busy(dev); pm_runtime_enable(dev);
+ pm_runtime_resume(bus->dev); + link_flags = md_flags >> (bus->link_id * 8);
if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) @@ -592,6 +597,7 @@ static int __maybe_unused intel_resume(struct device *dev) * counters and delay the pm_runtime suspend by several * seconds, by when all enumeration should be complete. */ + pm_runtime_mark_last_busy(bus->dev); pm_runtime_mark_last_busy(dev);
return 0;
On Thu, Aug 03, 2023 at 02:52:20PM +0800, Bard Liao wrote:
From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com
The SoundWire bus is handled with a dedicated device, which is placed between the Intel auxiliary device and peripheral devices, e.g.
soundwire_intel.link.0/sdw-master-0/sdw:0:025d:0711:01
The functionality of this 'sdw-master' device is limited, specifically for pm_runtime the ASoC framework will not rely on pm_runtime_get_sync() since it does not register any components. It will only change status thanks to the parent-child relationship which guarantees that the 'sdw-master' device will be pm_runtime resumed before any peripheral device.
However on startup and system resume it's possible that only the auxiliary device is pm_runtime active, and the peripheral will only become active during its io_init routine, leading to another occurrence of the error reported by the pm_runtime framework:
rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active
This patch suggests aligning the sdw-master device status to that of the auxiliary device. The difference between the two is completely notional and their pm_status shouldn't be different during the startup and system resume steps.
This problem was exposed by recent changes in the timing of the bus reset, but was present in this driver since we introduced pm_runtime support.
Closes: https://github.com/thesofproject/linux/issues/4328 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan ranjani.sridharan@linux.intel.com Reviewed-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com
Tested-by: Charles Keepax ckeepax@opensource.cirrus.com
Thanks, Charles
On Thu, 03 Aug 2023 14:52:18 +0800, Bard Liao wrote:
This patchset improves the pm_runtime behavior in rare corner cases identified by the Intel CI in the last 6 months.
a) in stress-tests, it's not uncommon to see the following type of warnings when the codec reports as ATTACHED
"rt711 sdw:0:025d:0711:00: runtime PM trying to activate child device sdw:0:025d:0711:00 but parent (sdw-master-0) is not active"
[...]
Applied, thanks!
[1/2] soundwire: intel_auxdevice: enable pm_runtime earlier on startup commit: 3d71f43f8a59a62c6ab832d4e73a69bae22e13b7 [2/2] soundWire: intel_auxdevice: resume 'sdw-master' on startup and system resume commit: f9031288110589c8f565683a182f194110338d65
Best regards,
participants (3)
-
Bard Liao
-
Charles Keepax
-
Vinod Koul