> Subject: Re: [PATCH V2] remoteproc: support self recovery after rproc crash > > Hi Peng, > > On 2/14/22 19:41, Arnaud POULIQUEN wrote: > > Hi Peng, > > > > On 1/26/22 09:51, Peng Fan (OSS) wrote: > >> From: Peng Fan <peng.fan@xxxxxxx> > >> > >> Current logic only support main processor to stop/start the remote > >> processor after rproc crash. However to SoC, such as i.MX8QM/QXP, the > >> remote processor could do self recovery after crash and trigger > >> watchdog reboot. It does not need main processor to load image, > >> stop/start M4 core. > > > > > > On stm32mp1 platform the remote processor watchdog generates an early > > interrupt that could be used to detach and reattach before the reset of the > remote processor. > > I need to test race condition,but I suppose that this should works if > > the resource table is not reinitialized by the remote processor firmware. > > > > Another option for the stm32mp1 is that remoteproc manages the reset > > of the remote processor. > > For instance this allows to save a core-dump before manually resetting > > the remote processor. > > But looks like this use case can be handled later, as mentioned below. > > > >> > >> This patch add a new flag to indicate whether the SoC has self > >> recovery capability. And introduce two functions: > >> rproc_self_recovery, rproc_assisted_recovery for the two cases. > >> Assisted recovery is as before, let main processor to help recovery, > >> while self recovery is recover itself withou help. To self recovery, > >> we only do detach and attach. > > > > > >> > >> Signed-off-by: Peng Fan <peng.fan@xxxxxxx> > >> --- > >> > >> V2: > >> Nothing change in V2. > >> Only move this patch out from > >> > >> https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpat > >> > chwork.kernel.org%2Fproject%2Flinux-remoteproc%2Flist%2F%3Fseries%3D > 6 > >> > 04364&data=04%7C01%7Cpeng.fan%40nxp.com%7C3d617c5ddb8c42b > 315f808d > >> > 9f79f2ac7%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C6378130 > 8526949 > >> > 0105%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2lu > MzIiLCJB > >> > TiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=VKKrqOnFz%2BoXjr%2 > FGMKpm4 > >> yyqmRfApeYY0l2V8A0yy4Y%3D&reserved=0 > >> > >> drivers/remoteproc/remoteproc_core.c | 66 > ++++++++++++++++++++-------- > >> include/linux/remoteproc.h | 2 + > >> 2 files changed, 49 insertions(+), 19 deletions(-) > >> > >> diff --git a/drivers/remoteproc/remoteproc_core.c > >> b/drivers/remoteproc/remoteproc_core.c > >> index 69f51acf235e..4bd5544dab8f 100644 > >> --- a/drivers/remoteproc/remoteproc_core.c > >> +++ b/drivers/remoteproc/remoteproc_core.c > >> @@ -1887,6 +1887,49 @@ static int __rproc_detach(struct rproc *rproc) > >> return 0; > >> } > >> > >> +static int rproc_self_recovery(struct rproc *rproc) { > >> + int ret; > >> + > >> + mutex_unlock(&rproc->lock); > >> + ret = rproc_detach(rproc); > >> + mutex_lock(&rproc->lock); > >> + if (ret) > >> + return ret; > > > > Here we would want to perform a core dump and manually reset the > > co-processor. > > I suppose that a new rproc ops could be called here in a next step. > > > >> + > >> + if (atomic_inc_return(&rproc->power) > 1) > >> + return 0; > > > > Do you identify a use case that needs to test rproc->power to skip the > > attach? > > If yes could you add a comment to describe it? > > > >> + return rproc_attach(rproc); > >> +} > >> + > >> +static int rproc_assisted_recovery(struct rproc *rproc) { > >> + const struct firmware *firmware_p; > >> + struct device *dev = &rproc->dev; > >> + int ret; > >> + > >> + ret = rproc_stop(rproc, true); > >> + if (ret) > >> + return ret; > >> + > >> + /* generate coredump */ > >> + rproc->ops->coredump(rproc); > >> + > >> + /* load firmware */ > >> + ret = request_firmware(&firmware_p, rproc->firmware, dev); > >> + if (ret < 0) { > >> + dev_err(dev, "request_firmware failed: %d\n", ret); > >> + return ret; > >> + } > >> + > >> + /* boot the remote processor up again */ > >> + ret = rproc_start(rproc, firmware_p); > >> + > >> + release_firmware(firmware_p); > >> + > >> + return ret; > >> +} > >> + > >> /** > >> * rproc_trigger_recovery() - recover a remoteproc > >> * @rproc: the remote processor > >> @@ -1901,7 +1944,6 @@ static int __rproc_detach(struct rproc *rproc) > >> */ > >> int rproc_trigger_recovery(struct rproc *rproc) { > >> - const struct firmware *firmware_p; > >> struct device *dev = &rproc->dev; > >> int ret; > >> > >> @@ -1915,24 +1957,10 @@ int rproc_trigger_recovery(struct rproc > >> *rproc) > >> > >> dev_err(dev, "recovering %s\n", rproc->name); > >> > >> - ret = rproc_stop(rproc, true); > >> - if (ret) > >> - goto unlock_mutex; > >> - > >> - /* generate coredump */ > >> - rproc->ops->coredump(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; > >> - } > >> - > >> - /* boot the remote processor up again */ > >> - ret = rproc_start(rproc, firmware_p); > >> - > >> - release_firmware(firmware_p); > >> + if (rproc->self_recovery) > >> + ret = rproc_self_recovery(rproc); > > > > If some platforms have to manually reset the remote processor (without > > reloading the firmware) the name could not be relevant... > > > > Following comments are only suggestions that needs to be commented by > > maintainers > > > > What about rproc_attach_recovery ? > > > >> + else > >> + ret = rproc_assisted_recovery(rproc); > > > > and rproc_firmware_recovery ? > > > > > >> > >> unlock_mutex: > >> mutex_unlock(&rproc->lock); > >> diff --git a/include/linux/remoteproc.h b/include/linux/remoteproc.h > >> index e0600e1e5c17..b32ef46f8aa4 100644 > >> --- a/include/linux/remoteproc.h > >> +++ b/include/linux/remoteproc.h > >> @@ -529,6 +529,7 @@ struct rproc_dump_segment { > >> * @elf_machine: firmware ELF machine > >> * @cdev: character device of the rproc > >> * @cdev_put_on_release: flag to indicate if remoteproc should be > >> shutdown on @char_dev release > >> + * @self_recovery: flag to indicate if remoteproc support self > >> + recovery > >> */ > >> struct rproc { > >> struct list_head node; > >> @@ -568,6 +569,7 @@ struct rproc { > >> u16 elf_machine; > >> struct cdev cdev; > >> bool cdev_put_on_release; > >> + bool self_recovery; > > > > This bool seems needed because we have lost the previous state before > crash. > > I wonder if a new rproc->state such as RPROC_REBOOT could avoid this > boolean. > > > > > > I will try to test you patch on stm32mp1 next week > > I performed few tests on the stm32mp1 with your patch. > Thanks to the resetting of the resource tables on detachment, this works > quite well. Thanks very much for you testing this patch. I'll try to address your previous comments and send out v3. Thanks, Peng. > > Regards, > Arnaud > > > > > Regards, > > Arnaud > > > >> }; > >> > >> /**
