Messages in this thread | | | From | Kevin Hilman <> | Subject | Re: [PATCH v4 1/3] power-domain: add power domain drivers for Rockchip platform | Date | Mon, 20 Oct 2014 14:31:17 -0700 |
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"jinkun.hong" <jinkun.hong@rock-chips.com> writes:
> From: "jinkun.hong" <jinkun.hong@rock-chips.com> > > Add power domain drivers based on generic power domain for Rockchip platform, > and support RK3288. > > Signed-off-by: Jack Dai <jack.dai@rock-chips.com> > Signed-off-by: jinkun.hong <jinkun.hong@rock-chips.com>
[...]
> +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?
> + return 0; > +}
Kevin
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