On Fri, Apr 08, 2016 at 05:53:56AM -0700, Guenter Roeck wrote: > Register with kernel restart handler instead of setting arm_pm_restart > directly. This enables support for replacing the PSCI restart handler > with a different handler if necessary for a specific board. > > Select a priority of 129 to indicate a higher than default priority, but > keep it as low as possible since PSCI reset is known to fail on some > boards.
For reference, which boards? It's unfortunate that that a PSCI 0.2+ implementation would be lacking a working SYSTEM_RESET implementation, and it's certainly a mistake to discourage. > Signed-off-by: Guenter Roeck <[email protected]> > --- > It might make sense to introduce a restart-priority property for devicetree > based configurations, but I am not sure if this would be acceptable. >From the DT side, I'm not keen on properties for priorities. They're incredibly fragile and don't really encode a HW property. A better option would be to have a property to describe how the PSCI implementation is broken (e.g. broken-system-reset), and not register the handler at all in that case. Thanks, Mark. > drivers/firmware/psci.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/drivers/firmware/psci.c b/drivers/firmware/psci.c > index 11bfee8b79a9..99fab3ac3fd5 100644 > --- a/drivers/firmware/psci.c > +++ b/drivers/firmware/psci.c > @@ -231,11 +231,18 @@ static int get_set_conduit_method(struct device_node > *np) > return 0; > } > > -static void psci_sys_reset(enum reboot_mode reboot_mode, const char *cmd) > +static int psci_sys_reset(struct notifier_block *np, unsigned long action, > + void *data) > { > invoke_psci_fn(PSCI_0_2_FN_SYSTEM_RESET, 0, 0, 0); > + return NOTIFY_DONE; > } > > +static struct notifier_block psci_sys_reset_nb = { > + .notifier_call = psci_sys_reset, > + .priority = 129, > +}; > + > static void psci_sys_poweroff(void) > { > invoke_psci_fn(PSCI_0_2_FN_SYSTEM_OFF, 0, 0, 0); > @@ -461,7 +468,7 @@ static void __init psci_0_2_set_functions(void) > > psci_ops.migrate_info_type = psci_migrate_info_type; > > - arm_pm_restart = psci_sys_reset; > + register_restart_handler(&psci_sys_reset_nb); > > pm_power_off = psci_sys_poweroff; > } > -- > 2.5.0 >
