| Message ID | 20200424200135.28825-11-mathieu.poirier@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | remoteproc: Add support for synchronisaton with rproc | expand |
On 4/24/20 10:01 PM, Mathieu Poirier wrote: > The remoteproc core must not allow function rproc_shutdown() to > proceed if currently synchronising with a remote processor and > the synchronisation operations of that remote processor does not > support it. Also part of the process is to set the synchronisation > flag so that the remoteproc core can make the right decisions when > restarting the system. > > Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > --- > drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ > drivers/remoteproc/remoteproc_internal.h | 7 ++++++ > 2 files changed, 39 insertions(+) > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > index 3a84a38ba37b..48afa1f80a8f 100644 > --- a/drivers/remoteproc/remoteproc_core.c > +++ b/drivers/remoteproc/remoteproc_core.c > @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) > } > EXPORT_SYMBOL(rproc_boot); > > +static bool rproc_can_shutdown(struct rproc *rproc) > +{ > + /* > + * The remoteproc core is the lifecycle manager, no problem > + * calling for a shutdown. > + */ > + if (!rproc_needs_syncing(rproc)) > + return true; > + > + /* > + * The remoteproc has been loaded by another entity (as per above > + * condition) and the platform code has given us the capability > + * of stopping it. > + */ > + if (rproc->sync_ops->stop) > + return true; This means that if rproc->sync_ops->stop is null rproc_stop_subdevices will not be called? seems not symmetric with the start sequence. Probably not useful to test it here as condition is already handled in rproc_stop_device... Regards Arnaud > + > + /* Any other condition should not be allowed */ > + return false; > +} > + > /** > * rproc_shutdown() - power off the remote processor > * @rproc: the remote processor > @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) > return; > } > > + if (!rproc_can_shutdown(rproc)) > + goto out; > + > /* if the remote proc is still needed, bail out */ > if (!atomic_dec_and_test(&rproc->power)) > goto out; > @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) > kfree(rproc->cached_table); > rproc->cached_table = NULL; > rproc->table_ptr = NULL; > + > + /* > + * The remote processor has been switched off - tell the core what > + * operation to use from hereon, i.e whether an external entity will > + * reboot the remote processor or it is now the remoteproc core's > + * responsability. > + */ > + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); > out: > mutex_unlock(&rproc->lock); > } > diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h > index 61500981155c..7dcc0a26892b 100644 > --- a/drivers/remoteproc/remoteproc_internal.h > +++ b/drivers/remoteproc/remoteproc_internal.h > @@ -27,6 +27,9 @@ struct rproc_debug_trace { > /* > * enum rproc_sync_states - remote processsor sync states > * > + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core > + * has shutdown (rproc_shutdown()) the > + * remote processor. > * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor > * has crashed but has not been recovered by > * the remoteproc core yet. > @@ -36,6 +39,7 @@ struct rproc_debug_trace { > * operation to use. > */ > enum rproc_sync_states { > + RPROC_SYNC_STATE_SHUTDOWN, > RPROC_SYNC_STATE_CRASHED, > }; > > @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, > enum rproc_sync_states state) > { > switch (state) { > + case RPROC_SYNC_STATE_SHUTDOWN: > + rproc->sync_with_rproc = rproc->sync_flags.after_stop; > + break; > case RPROC_SYNC_STATE_CRASHED: > rproc->sync_with_rproc = rproc->sync_flags.after_crash; > break; >
On Wed, Apr 29, 2020 at 10:19:49AM +0200, Arnaud POULIQUEN wrote: > > > On 4/24/20 10:01 PM, Mathieu Poirier wrote: > > The remoteproc core must not allow function rproc_shutdown() to > > proceed if currently synchronising with a remote processor and > > the synchronisation operations of that remote processor does not > > support it. Also part of the process is to set the synchronisation > > flag so that the remoteproc core can make the right decisions when > > restarting the system. > > > > Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > > --- > > drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ > > drivers/remoteproc/remoteproc_internal.h | 7 ++++++ > > 2 files changed, 39 insertions(+) > > > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > > index 3a84a38ba37b..48afa1f80a8f 100644 > > --- a/drivers/remoteproc/remoteproc_core.c > > +++ b/drivers/remoteproc/remoteproc_core.c > > @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) > > } > > EXPORT_SYMBOL(rproc_boot); > > > > +static bool rproc_can_shutdown(struct rproc *rproc) > > +{ > > + /* > > + * The remoteproc core is the lifecycle manager, no problem > > + * calling for a shutdown. > > + */ > > + if (!rproc_needs_syncing(rproc)) > > + return true; > > + > > + /* > > + * The remoteproc has been loaded by another entity (as per above > > + * condition) and the platform code has given us the capability > > + * of stopping it. > > + */ > > + if (rproc->sync_ops->stop) > > + return true; > > This means that if rproc->sync_ops->stop is null rproc_stop_subdevices will not > be called? seems not symmetric with the start sequence. If rproc->sync_ops->stop is not provided then the remoteproc core can't stop the remote processor at all after it has synchronised with it. If a usecase requires some kind of soft reset then a stop() function that uses a mailbox notification or some other mechanism can be provided to tell the remote processor to put itself back in startup mode again. Is this fine with you or there is still something I don't get? > Probably not useful to test it here as condition is already handled in rproc_stop_device... > > Regards > Arnaud > > + > > + /* Any other condition should not be allowed */ > > + return false; > > +} > > + > > /** > > * rproc_shutdown() - power off the remote processor > > * @rproc: the remote processor > > @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) > > return; > > } > > > > + if (!rproc_can_shutdown(rproc)) > > + goto out; > > + > > /* if the remote proc is still needed, bail out */ > > if (!atomic_dec_and_test(&rproc->power)) > > goto out; > > @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) > > kfree(rproc->cached_table); > > rproc->cached_table = NULL; > > rproc->table_ptr = NULL; > > + > > + /* > > + * The remote processor has been switched off - tell the core what > > + * operation to use from hereon, i.e whether an external entity will > > + * reboot the remote processor or it is now the remoteproc core's > > + * responsability. > > + */ > > + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); > > out: > > mutex_unlock(&rproc->lock); > > } > > diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h > > index 61500981155c..7dcc0a26892b 100644 > > --- a/drivers/remoteproc/remoteproc_internal.h > > +++ b/drivers/remoteproc/remoteproc_internal.h > > @@ -27,6 +27,9 @@ struct rproc_debug_trace { > > /* > > * enum rproc_sync_states - remote processsor sync states > > * > > + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core > > + * has shutdown (rproc_shutdown()) the > > + * remote processor. > > * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor > > * has crashed but has not been recovered by > > * the remoteproc core yet. > > @@ -36,6 +39,7 @@ struct rproc_debug_trace { > > * operation to use. > > */ > > enum rproc_sync_states { > > + RPROC_SYNC_STATE_SHUTDOWN, > > RPROC_SYNC_STATE_CRASHED, > > }; > > > > @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, > > enum rproc_sync_states state) > > { > > switch (state) { > > + case RPROC_SYNC_STATE_SHUTDOWN: > > + rproc->sync_with_rproc = rproc->sync_flags.after_stop; > > + break; > > case RPROC_SYNC_STATE_CRASHED: > > rproc->sync_with_rproc = rproc->sync_flags.after_crash; > > break; > >
On 4/30/20 10:23 PM, Mathieu Poirier wrote: > On Wed, Apr 29, 2020 at 10:19:49AM +0200, Arnaud POULIQUEN wrote: >> >> >> On 4/24/20 10:01 PM, Mathieu Poirier wrote: >>> The remoteproc core must not allow function rproc_shutdown() to >>> proceed if currently synchronising with a remote processor and >>> the synchronisation operations of that remote processor does not >>> support it. Also part of the process is to set the synchronisation >>> flag so that the remoteproc core can make the right decisions when >>> restarting the system. >>> >>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> >>> --- >>> drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ >>> drivers/remoteproc/remoteproc_internal.h | 7 ++++++ >>> 2 files changed, 39 insertions(+) >>> >>> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c >>> index 3a84a38ba37b..48afa1f80a8f 100644 >>> --- a/drivers/remoteproc/remoteproc_core.c >>> +++ b/drivers/remoteproc/remoteproc_core.c >>> @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) >>> } >>> EXPORT_SYMBOL(rproc_boot); >>> >>> +static bool rproc_can_shutdown(struct rproc *rproc) >>> +{ >>> + /* >>> + * The remoteproc core is the lifecycle manager, no problem >>> + * calling for a shutdown. >>> + */ >>> + if (!rproc_needs_syncing(rproc)) >>> + return true; >>> + >>> + /* >>> + * The remoteproc has been loaded by another entity (as per above >>> + * condition) and the platform code has given us the capability >>> + * of stopping it. >>> + */ >>> + if (rproc->sync_ops->stop) >>> + return true; >> >> This means that if rproc->sync_ops->stop is null rproc_stop_subdevices will not >> be called? seems not symmetric with the start sequence. > > If rproc->sync_ops->stop is not provided then the remoteproc core can't stop the > remote processor at all after it has synchronised with it. If a usecase > requires some kind of soft reset then a stop() function that uses a mailbox > notification or some other mechanism can be provided to tell the remote > processor to put itself back in startup mode again. > > Is this fine with you or there is still something I don't get? My point here is more around the subdevices. But perhaps i missed something... In rproc_start rproc_start_subdevices is called, even if sync_start is null. But in rproc_shutdown rproc_stop is not called, if sync_ops->stop is null. So rproc_stop_subdevices is not called in this case. Then if sync_flags.after_stop is false, it looks like that something will go wrong at next start. > >> Probably not useful to test it here as condition is already handled in rproc_stop_device... >> >> Regards >> Arnaud >>> + >>> + /* Any other condition should not be allowed */ >>> + return false; >>> +} >>> + >>> /** >>> * rproc_shutdown() - power off the remote processor >>> * @rproc: the remote processor >>> @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) >>> return; >>> } >>> >>> + if (!rproc_can_shutdown(rproc)) >>> + goto out; >>> + >>> /* if the remote proc is still needed, bail out */ >>> if (!atomic_dec_and_test(&rproc->power)) >>> goto out; >>> @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) >>> kfree(rproc->cached_table); >>> rproc->cached_table = NULL; >>> rproc->table_ptr = NULL; >>> + >>> + /* >>> + * The remote processor has been switched off - tell the core what >>> + * operation to use from hereon, i.e whether an external entity will >>> + * reboot the remote processor or it is now the remoteproc core's >>> + * responsability. >>> + */ >>> + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); >>> out: >>> mutex_unlock(&rproc->lock); >>> } >>> diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h >>> index 61500981155c..7dcc0a26892b 100644 >>> --- a/drivers/remoteproc/remoteproc_internal.h >>> +++ b/drivers/remoteproc/remoteproc_internal.h >>> @@ -27,6 +27,9 @@ struct rproc_debug_trace { >>> /* >>> * enum rproc_sync_states - remote processsor sync states >>> * >>> + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core >>> + * has shutdown (rproc_shutdown()) the >>> + * remote processor. >>> * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor >>> * has crashed but has not been recovered by >>> * the remoteproc core yet. >>> @@ -36,6 +39,7 @@ struct rproc_debug_trace { >>> * operation to use. >>> */ >>> enum rproc_sync_states { >>> + RPROC_SYNC_STATE_SHUTDOWN, >>> RPROC_SYNC_STATE_CRASHED, >>> }; >>> >>> @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, >>> enum rproc_sync_states state) >>> { >>> switch (state) { >>> + case RPROC_SYNC_STATE_SHUTDOWN: >>> + rproc->sync_with_rproc = rproc->sync_flags.after_stop; >>> + break; >>> case RPROC_SYNC_STATE_CRASHED: >>> rproc->sync_with_rproc = rproc->sync_flags.after_crash; >>> break; >>>
On Mon, May 04, 2020 at 01:34:43PM +0200, Arnaud POULIQUEN wrote: > > > On 4/30/20 10:23 PM, Mathieu Poirier wrote: > > On Wed, Apr 29, 2020 at 10:19:49AM +0200, Arnaud POULIQUEN wrote: > >> > >> > >> On 4/24/20 10:01 PM, Mathieu Poirier wrote: > >>> The remoteproc core must not allow function rproc_shutdown() to > >>> proceed if currently synchronising with a remote processor and > >>> the synchronisation operations of that remote processor does not > >>> support it. Also part of the process is to set the synchronisation > >>> flag so that the remoteproc core can make the right decisions when > >>> restarting the system. > >>> > >>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > >>> --- > >>> drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ > >>> drivers/remoteproc/remoteproc_internal.h | 7 ++++++ > >>> 2 files changed, 39 insertions(+) > >>> > >>> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > >>> index 3a84a38ba37b..48afa1f80a8f 100644 > >>> --- a/drivers/remoteproc/remoteproc_core.c > >>> +++ b/drivers/remoteproc/remoteproc_core.c > >>> @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) > >>> } > >>> EXPORT_SYMBOL(rproc_boot); > >>> > >>> +static bool rproc_can_shutdown(struct rproc *rproc) > >>> +{ > >>> + /* > >>> + * The remoteproc core is the lifecycle manager, no problem > >>> + * calling for a shutdown. > >>> + */ > >>> + if (!rproc_needs_syncing(rproc)) > >>> + return true; > >>> + > >>> + /* > >>> + * The remoteproc has been loaded by another entity (as per above > >>> + * condition) and the platform code has given us the capability > >>> + * of stopping it. > >>> + */ > >>> + if (rproc->sync_ops->stop) > >>> + return true; > >> > >> This means that if rproc->sync_ops->stop is null rproc_stop_subdevices will not > >> be called? seems not symmetric with the start sequence. > > > > If rproc->sync_ops->stop is not provided then the remoteproc core can't stop the > > remote processor at all after it has synchronised with it. If a usecase > > requires some kind of soft reset then a stop() function that uses a mailbox > > notification or some other mechanism can be provided to tell the remote > > processor to put itself back in startup mode again. > > > > Is this fine with you or there is still something I don't get? > > My point here is more around the subdevices. But perhaps i missed something... > > In rproc_start rproc_start_subdevices is called, even if sync_start is null. Here I'll take that you mean sync_ops::start() > But in rproc_shutdown rproc_stop is not called, if sync_ops->stop is null. > So rproc_stop_subdevices is not called in this case. Correct. I am pretty sure some people don't want the remoteproc core to be able to do anything other than synchronise with a remote processor, be it at boot time or when the remote processor has crashed. I can also see scenarios where people want to be able to start and stop subdevices from the remoteproc core, but _not_ power cycle the remote processor. In such cases the sync_ops::stop() should be some kind of notification telling the remote processor to put itself back in initialisation mode and sync_flags.after_stop should be set to true. > Then if sync_flags.after_stop is false, it looks like that something will go wrong > at next start. If sync_ops::stop is NULL then the value of sync_flags.after_stop becomes irrelevant because that state can't be reached. Let me know if you found a condition where this isn't the case and I will correct it. > > > > >> Probably not useful to test it here as condition is already handled in rproc_stop_device... > >> > >> Regards > >> Arnaud > >>> + > >>> + /* Any other condition should not be allowed */ > >>> + return false; > >>> +} > >>> + > >>> /** > >>> * rproc_shutdown() - power off the remote processor > >>> * @rproc: the remote processor > >>> @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) > >>> return; > >>> } > >>> > >>> + if (!rproc_can_shutdown(rproc)) > >>> + goto out; > >>> + > >>> /* if the remote proc is still needed, bail out */ > >>> if (!atomic_dec_and_test(&rproc->power)) > >>> goto out; > >>> @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) > >>> kfree(rproc->cached_table); > >>> rproc->cached_table = NULL; > >>> rproc->table_ptr = NULL; > >>> + > >>> + /* > >>> + * The remote processor has been switched off - tell the core what > >>> + * operation to use from hereon, i.e whether an external entity will > >>> + * reboot the remote processor or it is now the remoteproc core's > >>> + * responsability. > >>> + */ > >>> + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); > >>> out: > >>> mutex_unlock(&rproc->lock); > >>> } > >>> diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h > >>> index 61500981155c..7dcc0a26892b 100644 > >>> --- a/drivers/remoteproc/remoteproc_internal.h > >>> +++ b/drivers/remoteproc/remoteproc_internal.h > >>> @@ -27,6 +27,9 @@ struct rproc_debug_trace { > >>> /* > >>> * enum rproc_sync_states - remote processsor sync states > >>> * > >>> + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core > >>> + * has shutdown (rproc_shutdown()) the > >>> + * remote processor. > >>> * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor > >>> * has crashed but has not been recovered by > >>> * the remoteproc core yet. > >>> @@ -36,6 +39,7 @@ struct rproc_debug_trace { > >>> * operation to use. > >>> */ > >>> enum rproc_sync_states { > >>> + RPROC_SYNC_STATE_SHUTDOWN, > >>> RPROC_SYNC_STATE_CRASHED, > >>> }; > >>> > >>> @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, > >>> enum rproc_sync_states state) > >>> { > >>> switch (state) { > >>> + case RPROC_SYNC_STATE_SHUTDOWN: > >>> + rproc->sync_with_rproc = rproc->sync_flags.after_stop; > >>> + break; > >>> case RPROC_SYNC_STATE_CRASHED: > >>> rproc->sync_with_rproc = rproc->sync_flags.after_crash; > >>> break; > >>>
On Fri 24 Apr 13:01 PDT 2020, Mathieu Poirier wrote: > The remoteproc core must not allow function rproc_shutdown() to > proceed if currently synchronising with a remote processor and > the synchronisation operations of that remote processor does not > support it. Also part of the process is to set the synchronisation > flag so that the remoteproc core can make the right decisions when > restarting the system. > > Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> > --- > drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ > drivers/remoteproc/remoteproc_internal.h | 7 ++++++ > 2 files changed, 39 insertions(+) > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > index 3a84a38ba37b..48afa1f80a8f 100644 > --- a/drivers/remoteproc/remoteproc_core.c > +++ b/drivers/remoteproc/remoteproc_core.c > @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) > } > EXPORT_SYMBOL(rproc_boot); > > +static bool rproc_can_shutdown(struct rproc *rproc) > +{ > + /* > + * The remoteproc core is the lifecycle manager, no problem > + * calling for a shutdown. > + */ > + if (!rproc_needs_syncing(rproc)) > + return true; > + > + /* > + * The remoteproc has been loaded by another entity (as per above > + * condition) and the platform code has given us the capability > + * of stopping it. > + */ > + if (rproc->sync_ops->stop) > + return true; > + > + /* Any other condition should not be allowed */ > + return false; > +} > + > /** > * rproc_shutdown() - power off the remote processor > * @rproc: the remote processor > @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) > return; > } > > + if (!rproc_can_shutdown(rproc)) > + goto out; There's been a request mentioned of it being possible to shut down Linux and having the remote processor keep running. By skipping the rest of shutdown we will not stop or unprepare subdevices, so presumably the remote processor won't know that virtio/rpmsg is down. Is that ok? > + > /* if the remote proc is still needed, bail out */ > if (!atomic_dec_and_test(&rproc->power)) > goto out; > @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) > kfree(rproc->cached_table); > rproc->cached_table = NULL; > rproc->table_ptr = NULL; > + > + /* > + * The remote processor has been switched off - tell the core what > + * operation to use from hereon, i.e whether an external entity will > + * reboot the remote processor or it is now the remoteproc core's > + * responsability. > + */ > + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); As asked on a previous patch, what would it mean if after_stop is true? It seems like this state would be similar to the "already-booted" state that we might encounter at probe time. Regards, Bjorn > out: > mutex_unlock(&rproc->lock); > } > diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h > index 61500981155c..7dcc0a26892b 100644 > --- a/drivers/remoteproc/remoteproc_internal.h > +++ b/drivers/remoteproc/remoteproc_internal.h > @@ -27,6 +27,9 @@ struct rproc_debug_trace { > /* > * enum rproc_sync_states - remote processsor sync states > * > + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core > + * has shutdown (rproc_shutdown()) the > + * remote processor. > * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor > * has crashed but has not been recovered by > * the remoteproc core yet. > @@ -36,6 +39,7 @@ struct rproc_debug_trace { > * operation to use. > */ > enum rproc_sync_states { > + RPROC_SYNC_STATE_SHUTDOWN, > RPROC_SYNC_STATE_CRASHED, > }; > > @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, > enum rproc_sync_states state) > { > switch (state) { > + case RPROC_SYNC_STATE_SHUTDOWN: > + rproc->sync_with_rproc = rproc->sync_flags.after_stop; > + break; > case RPROC_SYNC_STATE_CRASHED: > rproc->sync_with_rproc = rproc->sync_flags.after_crash; > break; > -- > 2.20.1 >
On 5/6/20 12:03 AM, Mathieu Poirier wrote: > On Mon, May 04, 2020 at 01:34:43PM +0200, Arnaud POULIQUEN wrote: >> >> >> On 4/30/20 10:23 PM, Mathieu Poirier wrote: >>> On Wed, Apr 29, 2020 at 10:19:49AM +0200, Arnaud POULIQUEN wrote: >>>> >>>> >>>> On 4/24/20 10:01 PM, Mathieu Poirier wrote: >>>>> The remoteproc core must not allow function rproc_shutdown() to >>>>> proceed if currently synchronising with a remote processor and >>>>> the synchronisation operations of that remote processor does not >>>>> support it. Also part of the process is to set the synchronisation >>>>> flag so that the remoteproc core can make the right decisions when >>>>> restarting the system. >>>>> >>>>> Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> >>>>> --- >>>>> drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ >>>>> drivers/remoteproc/remoteproc_internal.h | 7 ++++++ >>>>> 2 files changed, 39 insertions(+) >>>>> >>>>> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c >>>>> index 3a84a38ba37b..48afa1f80a8f 100644 >>>>> --- a/drivers/remoteproc/remoteproc_core.c >>>>> +++ b/drivers/remoteproc/remoteproc_core.c >>>>> @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) >>>>> } >>>>> EXPORT_SYMBOL(rproc_boot); >>>>> >>>>> +static bool rproc_can_shutdown(struct rproc *rproc) >>>>> +{ >>>>> + /* >>>>> + * The remoteproc core is the lifecycle manager, no problem >>>>> + * calling for a shutdown. >>>>> + */ >>>>> + if (!rproc_needs_syncing(rproc)) >>>>> + return true; >>>>> + >>>>> + /* >>>>> + * The remoteproc has been loaded by another entity (as per above >>>>> + * condition) and the platform code has given us the capability >>>>> + * of stopping it. >>>>> + */ >>>>> + if (rproc->sync_ops->stop) >>>>> + return true; >>>> >>>> This means that if rproc->sync_ops->stop is null rproc_stop_subdevices will not >>>> be called? seems not symmetric with the start sequence. >>> >>> If rproc->sync_ops->stop is not provided then the remoteproc core can't stop the >>> remote processor at all after it has synchronised with it. If a usecase >>> requires some kind of soft reset then a stop() function that uses a mailbox >>> notification or some other mechanism can be provided to tell the remote >>> processor to put itself back in startup mode again. >>> >>> Is this fine with you or there is still something I don't get? >> >> My point here is more around the subdevices. But perhaps i missed something... >> >> In rproc_start rproc_start_subdevices is called, even if sync_start is null. > > Here I'll take that you mean sync_ops::start() > >> But in rproc_shutdown rproc_stop is not called, if sync_ops->stop is null. >> So rproc_stop_subdevices is not called in this case. > > Correct. I am pretty sure some people don't want the remoteproc core to be able > to do anything other than synchronise with a remote processor, be it at boot > time or when the remote processor has crashed. > > I can also see scenarios where people want to be able to start and stop > subdevices from the remoteproc core, but _not_ power cycle the remote processor. > In such cases the sync_ops::stop() should be some kind of notification telling > the remote processor to put itself back in initialisation mode and > sync_flags.after_stop should be set to true. > >> Then if sync_flags.after_stop is false, it looks like that something will go wrong >> at next start. > > If sync_ops::stop is NULL then the value of sync_flags.after_stop becomes > irrelevant because that state can't be reached. Let me know if you found a > condition where this isn't the case and I will correct it. The only condition i have in mind is that the sync_ops::stop() can not implemented in platform driver, just because nothing to do. But i don't know if it is a realistic use case and having a dummy stop function looks to me acceptable in this particular use case. This triggers me another comment :) the rproc_ops struct description is relevant for the "normal" ops but not adapted for the sync_ops. For instance the start & stop are mandatory for ops, optional for sync_ops As this description is a reference (at least for me) to determine optional and mandatory ops would be useful to update it. Regards, Arnaud > >> >>> >>>> Probably not useful to test it here as condition is already handled in rproc_stop_device... >>>> >>>> Regards >>>> Arnaud >>>>> + >>>>> + /* Any other condition should not be allowed */ >>>>> + return false; >>>>> +} >>>>> + >>>>> /** >>>>> * rproc_shutdown() - power off the remote processor >>>>> * @rproc: the remote processor >>>>> @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) >>>>> return; >>>>> } >>>>> >>>>> + if (!rproc_can_shutdown(rproc)) >>>>> + goto out; >>>>> + >>>>> /* if the remote proc is still needed, bail out */ >>>>> if (!atomic_dec_and_test(&rproc->power)) >>>>> goto out; >>>>> @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) >>>>> kfree(rproc->cached_table); >>>>> rproc->cached_table = NULL; >>>>> rproc->table_ptr = NULL; >>>>> + >>>>> + /* >>>>> + * The remote processor has been switched off - tell the core what >>>>> + * operation to use from hereon, i.e whether an external entity will >>>>> + * reboot the remote processor or it is now the remoteproc core's >>>>> + * responsability. >>>>> + */ >>>>> + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); >>>>> out: >>>>> mutex_unlock(&rproc->lock); >>>>> } >>>>> diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h >>>>> index 61500981155c..7dcc0a26892b 100644 >>>>> --- a/drivers/remoteproc/remoteproc_internal.h >>>>> +++ b/drivers/remoteproc/remoteproc_internal.h >>>>> @@ -27,6 +27,9 @@ struct rproc_debug_trace { >>>>> /* >>>>> * enum rproc_sync_states - remote processsor sync states >>>>> * >>>>> + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core >>>>> + * has shutdown (rproc_shutdown()) the >>>>> + * remote processor. >>>>> * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor >>>>> * has crashed but has not been recovered by >>>>> * the remoteproc core yet. >>>>> @@ -36,6 +39,7 @@ struct rproc_debug_trace { >>>>> * operation to use. >>>>> */ >>>>> enum rproc_sync_states { >>>>> + RPROC_SYNC_STATE_SHUTDOWN, >>>>> RPROC_SYNC_STATE_CRASHED, >>>>> }; >>>>> >>>>> @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, >>>>> enum rproc_sync_states state) >>>>> { >>>>> switch (state) { >>>>> + case RPROC_SYNC_STATE_SHUTDOWN: >>>>> + rproc->sync_with_rproc = rproc->sync_flags.after_stop; >>>>> + break; >>>>> case RPROC_SYNC_STATE_CRASHED: >>>>> rproc->sync_with_rproc = rproc->sync_flags.after_crash; >>>>> break; >>>>>
diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c index 3a84a38ba37b..48afa1f80a8f 100644 --- a/drivers/remoteproc/remoteproc_core.c +++ b/drivers/remoteproc/remoteproc_core.c @@ -1849,6 +1849,27 @@ int rproc_boot(struct rproc *rproc) } EXPORT_SYMBOL(rproc_boot); +static bool rproc_can_shutdown(struct rproc *rproc) +{ + /* + * The remoteproc core is the lifecycle manager, no problem + * calling for a shutdown. + */ + if (!rproc_needs_syncing(rproc)) + return true; + + /* + * The remoteproc has been loaded by another entity (as per above + * condition) and the platform code has given us the capability + * of stopping it. + */ + if (rproc->sync_ops->stop) + return true; + + /* Any other condition should not be allowed */ + return false; +} + /** * rproc_shutdown() - power off the remote processor * @rproc: the remote processor @@ -1879,6 +1900,9 @@ void rproc_shutdown(struct rproc *rproc) return; } + if (!rproc_can_shutdown(rproc)) + goto out; + /* if the remote proc is still needed, bail out */ if (!atomic_dec_and_test(&rproc->power)) goto out; @@ -1898,6 +1922,14 @@ void rproc_shutdown(struct rproc *rproc) kfree(rproc->cached_table); rproc->cached_table = NULL; rproc->table_ptr = NULL; + + /* + * The remote processor has been switched off - tell the core what + * operation to use from hereon, i.e whether an external entity will + * reboot the remote processor or it is now the remoteproc core's + * responsability. + */ + rproc_set_sync_flag(rproc, RPROC_SYNC_STATE_SHUTDOWN); out: mutex_unlock(&rproc->lock); } diff --git a/drivers/remoteproc/remoteproc_internal.h b/drivers/remoteproc/remoteproc_internal.h index 61500981155c..7dcc0a26892b 100644 --- a/drivers/remoteproc/remoteproc_internal.h +++ b/drivers/remoteproc/remoteproc_internal.h @@ -27,6 +27,9 @@ struct rproc_debug_trace { /* * enum rproc_sync_states - remote processsor sync states * + * @RPROC_SYNC_STATE_SHUTDOWN state to use after the remoteproc core + * has shutdown (rproc_shutdown()) the + * remote processor. * @RPROC_SYNC_STATE_CRASHED state to use after the remote processor * has crashed but has not been recovered by * the remoteproc core yet. @@ -36,6 +39,7 @@ struct rproc_debug_trace { * operation to use. */ enum rproc_sync_states { + RPROC_SYNC_STATE_SHUTDOWN, RPROC_SYNC_STATE_CRASHED, }; @@ -43,6 +47,9 @@ static inline void rproc_set_sync_flag(struct rproc *rproc, enum rproc_sync_states state) { switch (state) { + case RPROC_SYNC_STATE_SHUTDOWN: + rproc->sync_with_rproc = rproc->sync_flags.after_stop; + break; case RPROC_SYNC_STATE_CRASHED: rproc->sync_with_rproc = rproc->sync_flags.after_crash; break;
The remoteproc core must not allow function rproc_shutdown() to proceed if currently synchronising with a remote processor and the synchronisation operations of that remote processor does not support it. Also part of the process is to set the synchronisation flag so that the remoteproc core can make the right decisions when restarting the system. Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org> --- drivers/remoteproc/remoteproc_core.c | 32 ++++++++++++++++++++++++ drivers/remoteproc/remoteproc_internal.h | 7 ++++++ 2 files changed, 39 insertions(+)