[PATCH V3 0/2] remoteproc: support self recovery

[PATCH V3 0/2] remoteproc: support self recovery

[Peng Fan (OSS)]

From: Peng Fan <peng.fan@nxp.com>

V3:
 Resend the wrong labeled patchset
 https://patchwork.kernel.org/project/linux-remoteproc/list/?series=621311

 Write a cover-letter
 To i.MX8QM/QXP, they have a M4 core self-recovery capability without
 Linux loading firmware. The self recovery is done by
 SCU(System Control Unit). Current remoteproc framework only support Linux
 help recovery remote processor(stop, loading firmware, start). This
 patchset is support remote processor self recovery(attach recovery).

 In order to avoid introducing a new variable(bool support_self_recovery),
 patch 1 introduce a new function, rproc_has_feature to make code easy to
 extend, cleaner, such as we could move "bool has_iommu" to
 rproc_has_feature(rproc, RPROC_FEAT_IOMMU).

 Patch 2 is introduce a new function rproc_attach_recovery for
 self recovery, the original logic move to rproc_firmware_recovery meaning
 needs linux to help recovery.

 V2-version 2:
 https://patchwork.kernel.org/project/linux-remoteproc/list/?series=621311
 Introduce rproc_has_feature

 V2-version 1:
 https://patchwork.kernel.org/project/linux-remoteproc/patch/20220126085120.3397450-1-peng.fan@oss.nxp.com/
 Nothing change in V2.
 Only move this patch out from
 https://patchwork.kernel.org/project/linux-remoteproc/list/?series=604364

Peng Fan (2):
  remoteproc: introduce rproc features
  remoteproc: support attach recovery after rproc crash

 drivers/remoteproc/remoteproc_core.c | 67 ++++++++++++++++++++--------
 include/linux/remoteproc.h           | 18 ++++++++
 2 files changed, 66 insertions(+), 19 deletions(-)

-- 
2.30.0

[PATCH V3 1/2] remoteproc: introduce rproc features

[Peng Fan (OSS)]

From: Peng Fan <peng.fan@nxp.com>

remote processor may support:
 - firmware recovery with help from main processor
 - self recovery without help from main processor
 - iommu
 - etc

Introduce rproc features could simplify code to avoid adding more bool
flags and let us optimize current code.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V3:
 Resend

V2-version 2:
 New

 include/linux/remoteproc.h | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h
index 93a1d0050fbc..51edaf80692c 100644
--- a/include/linux/remoteproc.h
+++ b/include/linux/remoteproc.h
@@ -417,6 +417,7 @@ struct rproc_ops {
  *			has attached to it
  * @RPROC_DETACHED:	device has been booted by another entity and waiting
  *			for the core to attach to it
+ * @RPROC_CRASHED_ATTACH_RECOVERY: device has crashed and self recovery
  * @RPROC_LAST:		just keep this one at the end
  *
  * Please note that the values of these states are used as indices
@@ -489,6 +490,11 @@ struct rproc_dump_segment {
 	loff_t offset;
 };
 
+enum rproc_features {
+	RPROC_FEAT_ATTACH_RECOVERY = 0,
+	RPROC_MAX_FEATURES = 32,
+};
+
 /**
  * struct rproc - represents a physical remote processor device
  * @node: list node of this rproc object
@@ -530,6 +536,7 @@ struct rproc_dump_segment {
  * @elf_machine: firmware ELF machine
  * @cdev: character device of the rproc
  * @cdev_put_on_release: flag to indicate if remoteproc should be shutdown on @char_dev release
+ * @features: indicate remoteproc features
  */
 struct rproc {
 	struct list_head node;
@@ -570,8 +577,19 @@ struct rproc {
 	u16 elf_machine;
 	struct cdev cdev;
 	bool cdev_put_on_release;
+	DECLARE_BITMAP(features, RPROC_MAX_FEATURES);
 };
 
+static inline bool rproc_has_feature(struct rproc *rproc, unsigned int feature)
+{
+	return test_bit(feature, rproc->features);
+}
+
+static inline void rproc_set_feature(struct rproc *rproc, unsigned int feature)
+{
+	set_bit(feature, rproc->features);
+}
+
 /**
  * struct rproc_subdev - subdevice tied to a remoteproc
  * @node: list node related to the rproc subdevs list
-- 
2.30.0

[PATCH V3 2/2] remoteproc: support attach recovery after rproc crash

[Peng Fan (OSS)]

From: Peng Fan <peng.fan@nxp.com>

Current logic only support main processor to stop/start the remote
processor after rproc crash. However to SoC, such as i.MX8QM/QXP, the
remote processor could do attach recovery after crash and trigger watchdog
reboot. It does not need main processor to load image, or stop/start M4
core.

Introduce two functions: rproc_attach_recovery, rproc_firmware_recovery
for the two cases. Firmware recovery is as before, let main processor to
help recovery, while attach recovery is recover itself withou help.
To attach recovery, we only do detach and attach.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---

V3:
 Resend with cover-letter

V2-version 2:
 use rproc_has_feature in patch 1/2
V2-version1:
 Nothing change in V2.
 Only move this patch out from
 https://patchwork.kernel.org/project/linux-remoteproc/list/?series=604364

 drivers/remoteproc/remoteproc_core.c | 67 ++++++++++++++++++++--------
 1 file changed, 48 insertions(+), 19 deletions(-)

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 69f51acf235e..366fad475898 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -1887,6 +1887,50 @@ static int __rproc_detach(struct rproc *rproc)
 	return 0;
 }
 
+static int rproc_attach_recovery(struct rproc *rproc)
+{
+	int ret;
+
+	mutex_unlock(&rproc->lock);
+	ret = rproc_detach(rproc);
+	mutex_lock(&rproc->lock);
+	if (ret)
+		return ret;
+
+	if (atomic_inc_return(&rproc->power) > 1)
+		return 0;
+
+	return rproc_attach(rproc);
+}
+
+static int rproc_firmware_recovery(struct rproc *rproc)
+{
+	const struct firmware *firmware_p;
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	ret = rproc_stop(rproc, true);
+	if (ret)
+		return ret;
+
+	/* generate coredump */
+	rproc->ops->coredump(rproc);
+
+	/* load firmware */
+	ret = request_firmware(&firmware_p, rproc->firmware, dev);
+	if (ret < 0) {
+		dev_err(dev, "request_firmware failed: %d\n", ret);
+		return ret;
+	}
+
+	/* boot the remote processor up again */
+	ret = rproc_start(rproc, firmware_p);
+
+	release_firmware(firmware_p);
+
+	return ret;
+}
+
 /**
  * rproc_trigger_recovery() - recover a remoteproc
  * @rproc: the remote processor
@@ -1901,7 +1945,6 @@ static int __rproc_detach(struct rproc *rproc)
  */
 int rproc_trigger_recovery(struct rproc *rproc)
 {
-	const struct firmware *firmware_p;
 	struct device *dev = &rproc->dev;
 	int ret;
 
@@ -1915,24 +1958,10 @@ int rproc_trigger_recovery(struct rproc *rproc)
 
 	dev_err(dev, "recovering %s\n", rproc->name);
 
-	ret = rproc_stop(rproc, true);
-	if (ret)
-		goto unlock_mutex;
-
-	/* generate coredump */
-	rproc->ops->coredump(rproc);
-
-	/* load firmware */
-	ret = request_firmware(&firmware_p, rproc->firmware, dev);
-	if (ret < 0) {
-		dev_err(dev, "request_firmware failed: %d\n", ret);
-		goto unlock_mutex;
-	}
-
-	/* boot the remote processor up again */
-	ret = rproc_start(rproc, firmware_p);
-
-	release_firmware(firmware_p);
+	if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_RECOVERY))
+		ret = rproc_attach_recovery(rproc);
+	else
+		ret = rproc_firmware_recovery(rproc);
 
 unlock_mutex:
 	mutex_unlock(&rproc->lock);
-- 
2.30.0

Re: [PATCH V3 2/2] remoteproc: support attach recovery after rproc crash

[Bjorn Andersson]

On Wed 09 Mar 17:01 CST 2022, Peng Fan (OSS) wrote:

> From: Peng Fan <peng.fan@nxp.com>
> 
> Current logic only support main processor to stop/start the remote
> processor after rproc crash. However to SoC, such as i.MX8QM/QXP, the
> remote processor could do attach recovery after crash and trigger watchdog
> reboot. It does not need main processor to load image, or stop/start M4
> core.
> 
> Introduce two functions: rproc_attach_recovery, rproc_firmware_recovery
> for the two cases. Firmware recovery is as before, let main processor to
> help recovery, while attach recovery is recover itself withou help.
> To attach recovery, we only do detach and attach.
> 
> Signed-off-by: Peng Fan <peng.fan@nxp.com>

Hi Peng,

Didn't spot this v3 as I reviewed v2, please see my feedback on that
version.

Regards,
Bjorn

> ---
> 
> V3:
>  Resend with cover-letter
> 
> V2-version 2:
>  use rproc_has_feature in patch 1/2
> V2-version1:
>  Nothing change in V2.
>  Only move this patch out from
>  https://patchwork.kernel.org/project/linux-remoteproc/list/?series=604364
> 
>  drivers/remoteproc/remoteproc_core.c | 67 ++++++++++++++++++++--------
>  1 file changed, 48 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 69f51acf235e..366fad475898 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1887,6 +1887,50 @@ static int __rproc_detach(struct rproc *rproc)
>  	return 0;
>  }
>  
> +static int rproc_attach_recovery(struct rproc *rproc)
> +{
> +	int ret;
> +
> +	mutex_unlock(&rproc->lock);
> +	ret = rproc_detach(rproc);
> +	mutex_lock(&rproc->lock);
> +	if (ret)
> +		return ret;
> +
> +	if (atomic_inc_return(&rproc->power) > 1)
> +		return 0;
> +
> +	return rproc_attach(rproc);
> +}
> +
> +static int rproc_firmware_recovery(struct rproc *rproc)
> +{
> +	const struct firmware *firmware_p;
> +	struct device *dev = &rproc->dev;
> +	int ret;
> +
> +	ret = rproc_stop(rproc, true);
> +	if (ret)
> +		return ret;
> +
> +	/* generate coredump */
> +	rproc->ops->coredump(rproc);
> +
> +	/* load firmware */
> +	ret = request_firmware(&firmware_p, rproc->firmware, dev);
> +	if (ret < 0) {
> +		dev_err(dev, "request_firmware failed: %d\n", ret);
> +		return ret;
> +	}
> +
> +	/* boot the remote processor up again */
> +	ret = rproc_start(rproc, firmware_p);
> +
> +	release_firmware(firmware_p);
> +
> +	return ret;
> +}
> +
>  /**
>   * rproc_trigger_recovery() - recover a remoteproc
>   * @rproc: the remote processor
> @@ -1901,7 +1945,6 @@ static int __rproc_detach(struct rproc *rproc)
>   */
>  int rproc_trigger_recovery(struct rproc *rproc)
>  {
> -	const struct firmware *firmware_p;
>  	struct device *dev = &rproc->dev;
>  	int ret;
>  
> @@ -1915,24 +1958,10 @@ int rproc_trigger_recovery(struct rproc *rproc)
>  
>  	dev_err(dev, "recovering %s\n", rproc->name);
>  
> -	ret = rproc_stop(rproc, true);
> -	if (ret)
> -		goto unlock_mutex;
> -
> -	/* generate coredump */
> -	rproc->ops->coredump(rproc);
> -
> -	/* load firmware */
> -	ret = request_firmware(&firmware_p, rproc->firmware, dev);
> -	if (ret < 0) {
> -		dev_err(dev, "request_firmware failed: %d\n", ret);
> -		goto unlock_mutex;
> -	}
> -
> -	/* boot the remote processor up again */
> -	ret = rproc_start(rproc, firmware_p);
> -
> -	release_firmware(firmware_p);
> +	if (rproc_has_feature(rproc, RPROC_FEAT_ATTACH_RECOVERY))
> +		ret = rproc_attach_recovery(rproc);
> +	else
> +		ret = rproc_firmware_recovery(rproc);
>  
>  unlock_mutex:
>  	mutex_unlock(&rproc->lock);
> -- 
> 2.30.0
>