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.
> >+
> >+ return 0;
> > }
Regards,
Bjorn
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