Re: [PATCH 3/3] irqchip: dw-apb-ictl: add PM support

From: Jisheng Zhang
Date: Wed Oct 08 2014 - 07:54:31 EST


Hi Thomas, Sebastian,

On Tue, 30 Sep 2014 14:52:54 -0700
Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:

> On Tue, 30 Sep 2014, Sebastian Hesselbarth wrote:
> > On 09/23/2014 08:35 AM, Jisheng Zhang wrote:
> > > This patch adds in support for S2R for dw-apb-ictl irqchip driver.
> > >
> > > Signed-off-by: Jisheng Zhang <jszhang@xxxxxxxxxxx>
> > > ---
> > > drivers/irqchip/irq-dw-apb-ictl.c | 19 +++++++++++++++++++
> > > 1 file changed, 19 insertions(+)
> > >
> > > diff --git a/drivers/irqchip/irq-dw-apb-ictl.c
> > > b/drivers/irqchip/irq-dw-apb-ictl.c
> > > index c136b67..53bb732 100644
> > > --- a/drivers/irqchip/irq-dw-apb-ictl.c
> > > +++ b/drivers/irqchip/irq-dw-apb-ictl.c
> > > @@ -50,6 +50,21 @@ static void dw_apb_ictl_handler(unsigned int irq,
> > > struct irq_desc *desc)
> > > chained_irq_exit(chip, desc);
> > > }
> > >
> > > +#ifdef CONFIG_PM
> > > +static void dw_apb_ictl_resume(struct irq_data *d)
> > > +{
> > > + struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> > > + struct irq_chip_type *ct = irq_data_get_chip_type(d);
> > > +
> > > + irq_gc_lock(gc);
> > > + writel_relaxed(~0, gc->reg_base + ct->regs.enable);
> > > + writel_relaxed(*ct->mask_cache, gc->reg_base + ct->regs.mask);
> > > + irq_gc_unlock(gc);
> > > +}
> >
> > I agree with the overall change, but may this also be suited for a
> > generic irq_chip helper instead of being a driver specific one?
> >
> > Maybe Thomas or Jason can comment on this.
>
> If we have enough similar resume callbacks, yes.
>
> > Also, now that you are using writel_relaxed, I understand that both
> > writes above can happen in any order? Are there any implication we
> > have to consider, i.e. do we require any of the registers above to
> > be written first?

The registers sits at device type memory, the writes should happen in the same
order as before.

Thanks for reviewing,
Jisheng

>
> Was about to ask that as well :)
>
> Thanks,
>
> tglx

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/