On Tue, 27 Dec 2022 10:36:38 +0000,
Pavan Kondeti <quic_pkondeti@xxxxxxxxxxx> wrote:
>
> Hi Yogesh,
>
> On Fri, Dec 23, 2022 at 12:05:40AM +0530, Yogesh Lal wrote:
> > When CPU enter in low power mode it disable the redistributor and
> > Group1 interrupts. And re-initialise the system registers on wakeup.
> >
> > But in case of failure to enter low power mode need to enable
> > the redistributor and Group1 interrupts.
> >
> > Signed-off-by: Yogesh Lal <quic_ylal@xxxxxxxxxxx>
> > ---
> > drivers/irqchip/irq-gic-v3.c | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
> > index 997104d..4904f00 100644
> > --- a/drivers/irqchip/irq-gic-v3.c
> > +++ b/drivers/irqchip/irq-gic-v3.c
> > @@ -1376,7 +1376,7 @@ static int gic_retrigger(struct irq_data *data)
> > static int gic_cpu_pm_notifier(struct notifier_block *self,
> > unsigned long cmd, void *v)
> > {
> > - if (cmd == CPU_PM_EXIT) {
> > + if (cmd == CPU_PM_EXIT || cmd == CPU_PM_ENTER_FAILED) {
> > if (gic_dist_security_disabled())
> > gic_enable_redist(true);
> > gic_cpu_sys_reg_init();
>
> static int gic_cpu_pm_notifier(struct notifier_block *self,
> unsigned long cmd, void *v)
> {
> if (cmd == CPU_PM_EXIT) {
> if (gic_dist_security_disabled())
> gic_enable_redist(true);
> gic_cpu_sys_reg_init();
> } else if (cmd == CPU_PM_ENTER && gic_dist_security_disabled()) {
> gic_write_grpen1(0);
> gic_enable_redist(false);
> }
> return NOTIFY_OK;
> }
>
> During CPU_PM_ENTER notification, we are not doing anything for the
> !gic_dist_security_disabled() case. Since CPU_PM_ENTER_FAILED notification
> arrive when CPU fails to power down, do we need to reinitialize the
> system registers? IOW, should we do different handling for CPU_PM_ENTER_FAILED
> based on gic_dist_security_disabled()?
What does it gain you apart from the extra complexity?
gic_cpu_sys_reg_init() does very little, and makes sure we're always
back into a sane state.
M.
--
Without deviation from the norm, progress is not possible.
