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