Re: [PATCH v4 1/3] power-domain: add power domain drivers for Rockchip platform

[Hong jinkun]

在 2014/10/21 5:31, Kevin Hilman 写道:
> "jinkun.hong" <jinkun.hong@xxxxxxxxxxxxxx> writes:
>
> > From: "jinkun.hong" <jinkun.hong@xxxxxxxxxxxxxx>
> >
> > Add power domain drivers based on generic power domain for Rockchip platform,
> > and support RK3288.
> >
> > Signed-off-by: Jack Dai <jack.dai@xxxxxxxxxxxxxx>
> > Signed-off-by: jinkun.hong <jinkun.hong@xxxxxxxxxxxxxx>
> [...]
>
> > +static int rockchip_pmu_set_idle_request(struct rockchip_domain *pd,
> > +					 bool idle)
> > +{
> > +	u32 idle_mask = BIT(pd->idle_shift);
> > +	u32 idle_target = idle << (pd->idle_shift);
> > +	u32 ack_mask = BIT(pd->ack_shift);
> > +	u32 ack_target = idle << (pd->ack_shift);
> > +	unsigned int mask = BIT(pd->req_shift);
> > +	unsigned int val;
> > +	unsigned long flags;
> > +
> > +	spin_lock_irqsave(&pd->idle_lock, flags);
> > +	val = (idle) ? mask : 0;
> > +	regmap_update_bits(pd->regmap_pmu, REQ_OFFSET, mask, val);
> > +	dsb();
> A summary of the locking and barriers here (or in changelog) would be
> helpful for reviewers to verify you're protecting what you need to
> protect.
>
> > +	do {
> > +		regmap_read(pd->regmap_pmu, ACK_OFFSET, &val);
> > +	} while ((val & ack_mask) != ack_target);
> > +
> > +	do {
> > +		regmap_read(pd->regmap_pmu, IDLE_OFFSET, &val);
> > +	} while ((val & idle_mask) != idle_target);
> > +
> > +	spin_unlock_irqrestore(&pd->idle_lock, flags);
> These IRQ-disabled while loops look like opportunities to lockup the
> system.  Maybe add a timeout or a maximum number of tries?
Ok,I will add a timeout in new version.
> > +	return 0;
> > +}
> Kevin
Thank you for your review.

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