| Message ID | 20230724223057.1208122-2-quic_eberman@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | Implement a PSCI SYSTEM_RESET2 reboot-mode driver | expand |
On Mon, Jul 24, 2023 at 03:30:51PM -0700, Elliot Berman wrote: > Allow magic from the reboot-mode driver to be defined, but 0. This is > useful when the register/command to trigger reboot needs 0 to be > written. This is the case when the "default" reboot mode is to enter a > crash dump collection mode (e.g. when triggered by a watchdog) and Linux > doing a normal reboot requires the setting to be explicitly reset to > zero. Sorry, it is not clear to me. The current code does not treat 0 as a valid value for magic. Since our platform has a meaning for 0 as a magic value, we are doing this correct? Basically we are allowing reboot-mode { mode-normal = <0x0>; ... } What is "default" reboot mode you are referring here? are you referring to enum reboot_mode reboot_mode DEFAULT_REBOOT_MODE defined in kernel/reboot.c? > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > --- > drivers/power/reset/reboot-mode.c | 14 ++++++-------- > 1 file changed, 6 insertions(+), 8 deletions(-) > > diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c > index b4076b10b893..a646aefa041b 100644 > --- a/drivers/power/reset/reboot-mode.c > +++ b/drivers/power/reset/reboot-mode.c > @@ -19,11 +19,10 @@ struct mode_info { > struct list_head list; > }; > > -static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, > - const char *cmd) > +static bool get_reboot_mode_magic(struct reboot_mode_driver *reboot, > + const char *cmd, unsigned int *magic) > { > const char *normal = "normal"; > - int magic = 0; > struct mode_info *info; > > if (!cmd) > @@ -31,12 +30,12 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, > > list_for_each_entry(info, &reboot->head, list) { > if (!strcmp(info->mode, cmd)) { > - magic = info->magic; > - break; > + *magic = info->magic; > + return true; > } > } > > - return magic; > + return false; > } > > static int reboot_mode_notify(struct notifier_block *this, > @@ -46,8 +45,7 @@ static int reboot_mode_notify(struct notifier_block *this, > unsigned int magic; > > reboot = container_of(this, struct reboot_mode_driver, reboot_notifier); > - magic = get_reboot_mode_magic(reboot, cmd); > - if (magic) > + if (get_reboot_mode_magic(reboot, cmd, &magic)) > reboot->write(reboot, magic); > > return NOTIFY_DONE; > -- > 2.41.0 > Thanks, Pavan
diff --git a/drivers/power/reset/reboot-mode.c b/drivers/power/reset/reboot-mode.c index b4076b10b893..a646aefa041b 100644 --- a/drivers/power/reset/reboot-mode.c +++ b/drivers/power/reset/reboot-mode.c @@ -19,11 +19,10 @@ struct mode_info { struct list_head list; }; -static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, - const char *cmd) +static bool get_reboot_mode_magic(struct reboot_mode_driver *reboot, + const char *cmd, unsigned int *magic) { const char *normal = "normal"; - int magic = 0; struct mode_info *info; if (!cmd) @@ -31,12 +30,12 @@ static unsigned int get_reboot_mode_magic(struct reboot_mode_driver *reboot, list_for_each_entry(info, &reboot->head, list) { if (!strcmp(info->mode, cmd)) { - magic = info->magic; - break; + *magic = info->magic; + return true; } } - return magic; + return false; } static int reboot_mode_notify(struct notifier_block *this, @@ -46,8 +45,7 @@ static int reboot_mode_notify(struct notifier_block *this, unsigned int magic; reboot = container_of(this, struct reboot_mode_driver, reboot_notifier); - magic = get_reboot_mode_magic(reboot, cmd); - if (magic) + if (get_reboot_mode_magic(reboot, cmd, &magic)) reboot->write(reboot, magic); return NOTIFY_DONE;
Allow magic from the reboot-mode driver to be defined, but 0. This is useful when the register/command to trigger reboot needs 0 to be written. This is the case when the "default" reboot mode is to enter a crash dump collection mode (e.g. when triggered by a watchdog) and Linux doing a normal reboot requires the setting to be explicitly reset to zero. Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> --- drivers/power/reset/reboot-mode.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-)