From: Kai Vehmanen kai.vehmanen@linux.intel.com

[ Upstream commit 171b53be635ac15d4feafeb33946035649b1ca14 ]

If there are failures in DSP runtime resume, the device state will not reach active and this makes it impossible e.g. to retrieve a possible DSP panic dump via "exception" debugfs node. If CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE=y is set, the data in cache is stale. If debugfs cache is not used, the region simply cannot be read.

To allow debugging these scenarios, update the debugfs cache contents in resume error handler. User-space can then later retrieve DSP panic and other state via debugfs (requires SOF debugfs cache to be enabled in build).

Reported-by: Curtis Malainey <cujomalainey@chromium.org Link: https://github.com/thesofproject/linux/issues/4274 Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com Reviewed-by: Curtis Malainey <cujomalainey@chromium.org Reviewed-by: Péter Ujfalusi <peter.ujfalusi@linux.intel.com Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com Link: https://lore.kernel.org/r/20230512104638.21376-1-peter.ujfalusi@linux.intel.... Signed-off-by: Mark Brown <broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- sound/soc/sof/pm.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/sound/soc/sof/pm.c b/sound/soc/sof/pm.c index 26ffcbb6e30f4..a1bfa5a37e2ad 100644 --- a/sound/soc/sof/pm.c +++ b/sound/soc/sof/pm.c @@ -159,7 +159,7 @@ static int sof_resume(struct device *dev, bool runtime_resume) ret = tplg_ops->set_up_all_pipelines(sdev, false); if (ret < 0) { dev_err(sdev->dev, "Failed to restore pipeline after resume %d\n", ret); - return ret; + goto setup_fail; } }

@@ -173,6 +173,18 @@ static int sof_resume(struct device *dev, bool runtime_resume) dev_err(sdev->dev, "ctx_restore IPC error during resume: %d\n", ret); }

+setup_fail: +#if IS_ENABLED(CONFIG_SND_SOC_SOF_DEBUG_ENABLE_DEBUGFS_CACHE) + if (ret < 0) { + /* + * Debugfs cannot be read in runtime suspend, so cache + * the contents upon failure. This allows to capture + * possible DSP coredump information. + */ + sof_cache_debugfs(sdev); + } +#endif + return ret; }