On Thu, Dec 26, 2019 at 09:32:13PM -0800, Bjorn Andersson wrote: > Introduce a "panic" function in the remoteproc ops table, to allow > remoteproc instances to perform operations needed in order to aid in > post mortem system debugging, such as flushing caches etc, when the > kernel panics. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx> > --- > > Changes since v1: > - None > > drivers/remoteproc/remoteproc_core.c | 17 +++++++++++++++++ > include/linux/remoteproc.h | 4 ++++ > 2 files changed, 21 insertions(+) > > diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c > index 307df98347ba..779f19d6d8e7 100644 > --- a/drivers/remoteproc/remoteproc_core.c > +++ b/drivers/remoteproc/remoteproc_core.c > @@ -1832,6 +1832,17 @@ void rproc_shutdown(struct rproc *rproc) > } > EXPORT_SYMBOL(rproc_shutdown); > > +static int rproc_panic_handler(struct notifier_block *nb, unsigned long event, > + void *ptr) > +{ > + struct rproc *rproc = container_of(nb, struct rproc, panic_nb); > + > + if (rproc->state == RPROC_RUNNING) > + rproc->ops->panic(rproc); > + > + return NOTIFY_DONE; > +} > + > /** > * rproc_get_by_phandle() - find a remote processor by phandle > * @phandle: phandle to the rproc > @@ -2057,6 +2068,12 @@ struct rproc *rproc_alloc(struct device *dev, const char *name, > rproc->ops->get_boot_addr = rproc_elf_get_boot_addr; > } > > + /* Register panic notifier for remoteprocs with "panic" callback */ > + if (rproc->ops->panic) { > + rproc->panic_nb.notifier_call = rproc_panic_handler; > + atomic_notifier_chain_register(&panic_notifier_list, &rproc->panic_nb); Line over 80 characters. > + } > + > mutex_init(&rproc->lock); > > idr_init(&rproc->notifyids); > diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h > index 16ad66683ad0..7836c528d309 100644 > --- a/include/linux/remoteproc.h > +++ b/include/linux/remoteproc.h > @@ -369,6 +369,7 @@ enum rsc_handling_status { > * expects to find it > * @sanity_check: sanity check the fw image > * @get_boot_addr: get boot address to entry point specified in firmware > + * @panic: optional callback to react to system panic > */ > struct rproc_ops { > int (*start)(struct rproc *rproc); > @@ -383,6 +384,7 @@ struct rproc_ops { > int (*load)(struct rproc *rproc, const struct firmware *fw); > int (*sanity_check)(struct rproc *rproc, const struct firmware *fw); > u32 (*get_boot_addr)(struct rproc *rproc, const struct firmware *fw); > + void (*panic)(struct rproc *rproc); > }; > > /** > @@ -481,6 +483,7 @@ struct rproc_dump_segment { > * @auto_boot: flag to indicate if remote processor should be auto-started > * @dump_segments: list of segments in the firmware > * @nb_vdev: number of vdev currently handled by rproc > + * @panic_nb: notifier_block for remoteproc's panic handler > */ > struct rproc { > struct list_head node; > @@ -514,6 +517,7 @@ struct rproc { > bool auto_boot; > struct list_head dump_segments; > int nb_vdev; > + struct notifier_block panic_nb; > }; > > /** > -- > 2.24.0 >