ASoC: SOF: pm: save io region state in case of errors in resume

Commit Message

Peter Ujfalusi May 12, 2023, 10:46 a.m. UTC

From: Kai Vehmanen <[e-mail]>

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 <[e-mail]>
Link: https://github.com/thesofproject/linux/issues/4274
Signed-off-by: Kai Vehmanen <[e-mail]>
Reviewed-by: Pierre-Louis Bossart <[e-mail]>
Reviewed-by: Ranjani Sridharan <[e-mail]>
Reviewed-by: Curtis Malainey <[e-mail]>
Reviewed-by: Péter Ujfalusi <[e-mail]>
Signed-off-by: Peter Ujfalusi <[e-mail]>
---
 sound/soc/sof/pm.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

Comments

Mark Brown May 15, 2023, 11:09 a.m. UTC | #1

On Fri, 12 May 2023 13:46:38 +0300, Peter Ujfalusi wrote:
> 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.
> 
> [...]

Applied to

   https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git for-next

Thanks!

[1/1] ASoC: SOF: pm: save io region state in case of errors in resume
      commit: 171b53be635ac15d4feafeb33946035649b1ca14

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

Patch

diff --git a/sound/soc/sof/pm.c b/sound/soc/sof/pm.c
index 2fdbc53ca715..2b232442e84b 100644
--- a/sound/soc/sof/pm.c
+++ b/sound/soc/sof/pm.c
@@ -164,7 +164,7 @@  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;
 		}
 	}
 
@@ -178,6 +178,18 @@  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;
 }