On Fri, Jun 21, 2024 at 05:00:56PM +0200, Richard Genoud wrote: > This patch adds the support for system suspend/resume to the ti_k3_R5 > remoteproc driver. > > In order to save maximum power, the approach here is to shutdown > completely the cores that were started by the kernel (i.e. those in > RUNNING state). > Those which were started before the kernel (in attached mode) will be > detached. > > The pm_notifier mechanism is used here because the remote procs firmwares > have to be reloaded at resume, and thus the driver must have access to > the file system were the firmware is stored. > > On suspend, the running remote procs are stopped, the attached remote > procs are detached and processor control released. > > On resume, the reverse operation is done. > > Based on work from: Hari Nagalla <hnagalla@xxxxxx> > > Signed-off-by: Richard Genoud <richard.genoud@xxxxxxxxxxx> > --- > drivers/remoteproc/ti_k3_r5_remoteproc.c | 123 ++++++++++++++++++++++- > 1 file changed, 121 insertions(+), 2 deletions(-) > > diff --git a/drivers/remoteproc/ti_k3_r5_remoteproc.c b/drivers/remoteproc/ti_k3_r5_remoteproc.c > index 39a47540c590..1f18b08618c8 100644 > --- a/drivers/remoteproc/ti_k3_r5_remoteproc.c > +++ b/drivers/remoteproc/ti_k3_r5_remoteproc.c > @@ -20,6 +20,7 @@ > #include <linux/platform_device.h> > #include <linux/pm_runtime.h> > #include <linux/remoteproc.h> > +#include <linux/suspend.h> > #include <linux/reset.h> > #include <linux/slab.h> > > @@ -112,6 +113,7 @@ struct k3_r5_cluster { > struct list_head cores; > wait_queue_head_t core_transition; > const struct k3_r5_soc_data *soc_data; > + struct notifier_block pm_notifier; > }; > > /** > @@ -577,7 +579,8 @@ static int k3_r5_rproc_start(struct rproc *rproc) > /* do not allow core 1 to start before core 0 */ > core0 = list_first_entry(&cluster->cores, struct k3_r5_core, > elem); > - if (core != core0 && core0->rproc->state == RPROC_OFFLINE) { > + if (core != core0 && (core0->rproc->state == RPROC_OFFLINE || > + core0->rproc->state == RPROC_SUSPENDED)) { If I understand correctly, this is to address a possible race condition between user space wanting to start core1 via sysfs while the system is being suspended. Is this correct? If so, please add a comment to explain what is going on. Otherwise a comment is obviously needed. > dev_err(dev, "%s: can not start core 1 before core 0\n", > __func__); > ret = -EPERM; > @@ -646,7 +649,8 @@ static int k3_r5_rproc_stop(struct rproc *rproc) > /* do not allow core 0 to stop before core 1 */ > core1 = list_last_entry(&cluster->cores, struct k3_r5_core, > elem); > - if (core != core1 && core1->rproc->state != RPROC_OFFLINE) { > + if (core != core1 && core1->rproc->state != RPROC_OFFLINE && > + core1->rproc->state != RPROC_SUSPENDED) { > dev_err(dev, "%s: can not stop core 0 before core 1\n", > __func__); > ret = -EPERM; > @@ -1238,6 +1242,117 @@ static int k3_r5_rproc_configure_mode(struct k3_r5_rproc *kproc) > return ret; > } > > +static int k3_r5_rproc_suspend(struct k3_r5_rproc *kproc) > +{ > + unsigned int rproc_state = kproc->rproc->state; > + int ret; > + > + if (rproc_state != RPROC_RUNNING && rproc_state != RPROC_ATTACHED) > + return 0; > + > + if (rproc_state == RPROC_RUNNING) > + ret = rproc_shutdown(kproc->rproc); > + else > + ret = rproc_detach(kproc->rproc); > + > + if (ret) { > + dev_err(kproc->dev, "Failed to %s rproc (%d)\n", > + (rproc_state == RPROC_RUNNING) ? "shutdown" : "detach", > + ret); > + return ret; > + } > + > + kproc->rproc->state = RPROC_SUSPENDED; > + > + return ret; > +} > + > +static int k3_r5_rproc_resume(struct k3_r5_rproc *kproc) > +{ > + int ret; > + > + if (kproc->rproc->state != RPROC_SUSPENDED) > + return 0; > + > + ret = k3_r5_rproc_configure_mode(kproc); > + if (ret < 0) > + return -EBUSY; > + > + /* > + * ret > 0 for IPC-only mode > + * ret == 0 for remote proc mode > + */ > + if (ret == 0) { > + /* > + * remote proc looses its configuration when powered off. > + * So, we have to configure it again on resume. > + */ > + ret = k3_r5_rproc_configure(kproc); > + if (ret < 0) { > + dev_err(kproc->dev, "k3_r5_rproc_configure failed (%d)\n", ret); > + return -EBUSY; > + } > + } > + > + return rproc_boot(kproc->rproc); > +} > + > +static int k3_r5_cluster_pm_notifier_call(struct notifier_block *bl, > + unsigned long state, void *unused) > +{ > + struct k3_r5_cluster *cluster = container_of(bl, struct k3_r5_cluster, > + pm_notifier); > + struct k3_r5_core *core; > + int ret; > + > + switch (state) { > + case PM_HIBERNATION_PREPARE: > + case PM_RESTORE_PREPARE: > + case PM_SUSPEND_PREPARE: > + /* core1 should be suspended before core0 */ > + list_for_each_entry_reverse(core, &cluster->cores, elem) { > + /* > + * In LOCKSTEP mode, rproc is allocated only for > + * core0 > + */ > + if (core->rproc) { > + ret = k3_r5_rproc_suspend(core->rproc->priv); > + if (ret) > + dev_warn(core->dev, > + "k3_r5_rproc_suspend failed (%d)\n", ret); > + } > + > + ret = ti_sci_proc_release(core->tsp); > + if (ret) > + dev_warn(core->dev, "ti_sci_proc_release failed (%d)\n", ret); > + } > + break; > + case PM_POST_HIBERNATION: > + case PM_POST_RESTORE: > + case PM_POST_SUSPEND: > + /* core0 should be started before core1 */ > + list_for_each_entry(core, &cluster->cores, elem) { > + ret = ti_sci_proc_request(core->tsp); > + if (ret) > + dev_warn(core->dev, "ti_sci_proc_request failed (%d)\n", ret); > + > + /* > + * In LOCKSTEP mode, rproc is allocated only for > + * core0 > + */ > + if (core->rproc) { > + ret = k3_r5_rproc_resume(core->rproc->priv); > + if (ret) > + dev_warn(core->dev, > + "k3_r5_rproc_resume failed (%d)\n", ret); > + } > + } > + break; > + } > + > + return 0; > +} > + > static int k3_r5_cluster_rproc_init(struct platform_device *pdev) > { > struct k3_r5_cluster *cluster = platform_get_drvdata(pdev); > @@ -1336,6 +1451,9 @@ static int k3_r5_cluster_rproc_init(struct platform_device *pdev) > } > } > > + cluster->pm_notifier.notifier_call = k3_r5_cluster_pm_notifier_call; > + register_pm_notifier(&cluster->pm_notifier); > + > return 0; > > err_split: > @@ -1402,6 +1520,7 @@ static void k3_r5_cluster_rproc_exit(void *data) > rproc_free(rproc); > core->rproc = NULL; > } > + unregister_pm_notifier(&cluster->pm_notifier); > } > > static int k3_r5_core_of_get_internal_memories(struct platform_device *pdev,