diff mbox

[1/2] remoteproc: Introduce rproc_{start,stop}() functions

Message ID 1493758742-26148-1-git-send-email-spjoshi@codeaurora.org (mailing list archive)
State New, archived
Headers show

Commit Message

Sarangdhar Joshi May 2, 2017, 8:59 p.m. UTC
In the context of recovering from crash,
rproc_trigger_recovery() does rproc_shutdown() followed
by rproc_boot(). The remoteproc resources are cleaned up
in rproc_shutdown() and immediately reallocated in
rproc_boot() which is an unnecessary overhead.

Furthermore, we want the memory regions to be accessible
after stopping the remote processor, to be able to extract
the memory content for a coredump.

The current patch factors out the code in rproc_boot() and
rproc_shutdown() path and introduces rproc_{start,stop}()
in order to avoid resource allocation overhead.

Signed-off-by: Sarangdhar Joshi <spjoshi@codeaurora.org>
---

I had forgot to send the second patch (2/2) in this series earlier.
Hence resending both patches as a series.

 drivers/remoteproc/remoteproc_core.c | 118 ++++++++++++++++++++++++++++++++---
 1 file changed, 110 insertions(+), 8 deletions(-)

Comments

Bjorn Andersson May 3, 2017, 12:02 a.m. UTC | #1
On Tue 02 May 13:59 PDT 2017, Sarangdhar Joshi wrote:

> In the context of recovering from crash,
> rproc_trigger_recovery() does rproc_shutdown() followed
> by rproc_boot(). The remoteproc resources are cleaned up
> in rproc_shutdown() and immediately reallocated in
> rproc_boot() which is an unnecessary overhead.
> 
> Furthermore, we want the memory regions to be accessible
> after stopping the remote processor, to be able to extract
> the memory content for a coredump.
> 
> The current patch factors out the code in rproc_boot() and

"This patch factors..."

> rproc_shutdown() path and introduces rproc_{start,stop}()
> in order to avoid resource allocation overhead.
> 

I think the result of the two patches looks good.

But I would prefer if you splice them differently. If I read the patches
correctly you should be able to introduce rproc_start()/stop() and move
rproc_boot()/shutdown() over to use these in one patch and then in a
second patch modify the behavior of the recovery.

That way if one bisects any issues to either one we know if it was the
refactoring or the modification of the recovery behavior.

Regards,
Bjorn
Sarangdhar Joshi May 3, 2017, 2:06 a.m. UTC | #2
On 05/02/2017 05:02 PM, Bjorn Andersson wrote:
> On Tue 02 May 13:59 PDT 2017, Sarangdhar Joshi wrote:
>
>> In the context of recovering from crash,
>> rproc_trigger_recovery() does rproc_shutdown() followed
>> by rproc_boot(). The remoteproc resources are cleaned up
>> in rproc_shutdown() and immediately reallocated in
>> rproc_boot() which is an unnecessary overhead.
>>
>> Furthermore, we want the memory regions to be accessible
>> after stopping the remote processor, to be able to extract
>> the memory content for a coredump.
>>
>> The current patch factors out the code in rproc_boot() and
>
> "This patch factors..."
>
>> rproc_shutdown() path and introduces rproc_{start,stop}()
>> in order to avoid resource allocation overhead.
>>
>
> I think the result of the two patches looks good.
>
> But I would prefer if you splice them differently. If I read the patches
> correctly you should be able to introduce rproc_start()/stop() and move
> rproc_boot()/shutdown() over to use these in one patch and then in a
> second patch modify the behavior of the recovery.
>
> That way if one bisects any issues to either one we know if it was the
> refactoring or the modification of the recovery behavior.

Yes, got your point. I will split it into two separate patches.

Regards,
Sarang

>
> Regards,
> Bjorn
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diff mbox

Patch

diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
index 9fd9ca5..169abb3 100644
--- a/drivers/remoteproc/remoteproc_core.c
+++ b/drivers/remoteproc/remoteproc_core.c
@@ -851,6 +851,61 @@  static void rproc_resource_cleanup(struct rproc *rproc)
 		kref_put(&rvdev->refcount, rproc_vdev_release);
 }
 
+static int rproc_start(struct rproc *rproc, const struct firmware *fw)
+{
+	struct device *dev = &rproc->dev;
+	struct resource_table *table, *loaded_table;
+	int ret, tablesz;
+
+	/* look for the resource table */
+	table = rproc_find_rsc_table(rproc, fw, &tablesz);
+	if (!table) {
+		dev_err(dev, "Resouce table look up failed\n");
+		return -EINVAL;
+	}
+
+	/* load the ELF segments to memory */
+	ret = rproc_load_segments(rproc, fw);
+	if (ret) {
+		dev_err(dev, "Failed to load program segments: %d\n", ret);
+		return ret;
+	}
+
+	/*
+	 * The starting device has been given the rproc->table_ptr as the
+	 * resource table. The address of the vring along with the other
+	 * allocated resources (carveouts etc) is stored in table_ptr.
+	 * In order to pass this information to the remote device we must copy
+	 * this information to device memory. We also update the table_ptr so
+	 * that any subsequent changes will be applied to the loaded version.
+	 */
+	loaded_table = rproc_find_loaded_rsc_table(rproc, fw);
+	if (loaded_table)
+		memcpy(loaded_table, rproc->table_ptr, tablesz);
+
+	/* power up the remote processor */
+	ret = rproc->ops->start(rproc);
+	if (ret) {
+		dev_err(dev, "can't start rproc %s: %d\n", rproc->name, ret);
+		return ret;
+	}
+
+	/* probe any subdevices for the remote processor */
+	ret = rproc_probe_subdevices(rproc);
+	if (ret) {
+		dev_err(dev, "failed to probe subdevices for %s: %d\n",
+			rproc->name, ret);
+		rproc->ops->stop(rproc);
+		return ret;
+	}
+
+	rproc->state = RPROC_RUNNING;
+
+	dev_info(dev, "remote processor %s is now up\n", rproc->name);
+
+	return 0;
+}
+
 /*
  * take a firmware and boot a remote processor with it.
  */
@@ -993,6 +1048,32 @@  static int rproc_trigger_auto_boot(struct rproc *rproc)
 	return ret;
 }
 
+static int rproc_stop(struct rproc *rproc)
+{
+	struct device *dev = &rproc->dev;
+	int ret;
+
+	/* remove any subdevices for the remote processor */
+	rproc_remove_subdevices(rproc);
+
+	/* power off the remote processor */
+	ret = rproc->ops->stop(rproc);
+	if (ret) {
+		dev_err(dev, "can't stop rproc: %d\n", ret);
+		return ret;
+	}
+
+	/* if in crash state, unlock crash handler */
+	if (rproc->state == RPROC_CRASHED)
+		complete_all(&rproc->crash_comp);
+
+	rproc->state = RPROC_OFFLINE;
+
+	dev_info(dev, "stopped remote processor %s\n", rproc->name);
+
+	return 0;
+}
+
 /**
  * rproc_trigger_recovery() - recover a remoteproc
  * @rproc: the remote processor
@@ -1005,23 +1086,44 @@  static int rproc_trigger_auto_boot(struct rproc *rproc)
  */
 int rproc_trigger_recovery(struct rproc *rproc)
 {
+	const struct firmware *firmware_p;
+	struct device *dev;
+	int ret;
+
 	dev_err(&rproc->dev, "recovering %s\n", rproc->name);
 
 	init_completion(&rproc->crash_comp);
 
-	/* shut down the remote */
-	/* TODO: make sure this works with rproc->power > 1 */
-	rproc_shutdown(rproc);
+	dev = &rproc->dev;
+
+	ret = mutex_lock_interruptible(&rproc->lock);
+	if (ret)
+		return ret;
+
+	ret = rproc_stop(rproc);
+	if (ret)
+		goto unlock_mutex;
 
 	/* wait until there is no more rproc users */
 	wait_for_completion(&rproc->crash_comp);
 
-	/*
-	 * boot the remote processor up again
-	 */
-	rproc_boot(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;
+	}
 
-	return 0;
+	/* boot the remote processor up again */
+	ret = rproc_start(rproc, firmware_p);
+	if (ret)
+		goto unlock_mutex;
+
+	release_firmware(firmware_p);
+
+unlock_mutex:
+	mutex_unlock(&rproc->lock);
+	return ret;
 }
 
 /**