On 08/04/2016 12:02 AM, Bjorn Andersson wrote:
On Tue 02 Aug 08:17 PDT 2016, loic pallardy wrote:
Hi Bjorn,
On 08/01/2016 08:58 PM, Bjorn Andersson wrote:
Introduce an "always-on" flag on rprocs to make it possible to flag
remote processors without vdevs to automatically boot once the firmware
is found.
Should this flag rather be named "auto-boot"? From my pov, "always-on" means
coprocessor can't be shutdown.
I saw it from the view of the remoteproc driver, in which case it's
always-on. But I'm fine with naming it "auto-boot" instead.
[..]
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
[..]
@@ -978,11 +982,16 @@ static int rproc_add_virtio_devices(struct rproc *rproc)
int rproc_trigger_recovery(struct rproc *rproc)
{
struct rproc_vdev *rvdev, *rvtmp;
+ 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);
+
/* clean up remote vdev entries */
list_for_each_entry_safe(rvdev, rvtmp, &rproc->rvdevs, node)
rproc_remove_virtio_dev(rvdev);
@@ -993,7 +1002,17 @@ int rproc_trigger_recovery(struct rproc *rproc)
/* Free the copy of the resource table */
kfree(rproc->cached_table);
- return rproc_add_virtio_devices(rproc);
+ ret = rproc_add_virtio_devices(rproc);
+ if (ret)
+ return ret;
+
+ /*
+ * boot the remote processor up again, waiting for the async fw load to
+ * finish
+ */
+ rproc_boot(rproc);
You are changing current behavior by forcing rproc boot whatever
"always-on". Moreover coprocessor already rebooted by
rproc_add_virtio_device if "always-on" flag is set, doesn't it?
If yes, rproc->power will be equal to 2 and rproc_shutdown call will failed
as this second rproc_boot call is unknown from customer pov.
rproc_add_virtio_devices() does no longer call rproc_boot(), this patch
moves that call. So for always-on rprocs "power" will go 1 -> 0 -> 1 in
this function.
What does change is that for a non-always-on case.
If we have 1 client that has requested rproc_boot() then the current
implementation will bring "power" down to 1 and we will wait until the
client for some reason calls rproc_shutdown(). After that we might boot
the system again, if there are any vdevs in the resource table.
Here we will bring "power" from 1 -> 0 -> 1, without regarding who's
holding references.
I'm fine with the final sequence in which only rproc_shutdown and
rproc_boot are called (with patch 3 modifications).
But having a look only to this patch, we have the following function call:
rproc_trigger_recovery
|__ rproc_shutdown --> power from 1 -> 0
|__ rproc_add_virtio_devices
|__ rproc_fw_config_virtio
|__ (if always_on == 1) rproc_boot_nowait --> power from 0 --> 1
|__ rproc_boot
if always_on == 1 power from 1 --> 2
else power from 0 --> 1
on this patch rproc_boot should be called only is always_on flag is not set.
With patch 3, call to rproc_add_virtio_devices is suppressed and
behavior is ok.
Regards,
Loic
+
+ return 0;
}
Regards,
Bjorn
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