Re: [PATCH V4 3/6] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device

[Vivek Gautam]

Hi Stephen,


On 07/13/2017 04:24 AM, Stephen Boyd wrote:
> On 07/06, Vivek Gautam wrote:
> > @@ -1231,12 +1237,18 @@ static int arm_smmu_map(struct iommu_domain *domain, unsigned long iova,
> >   static size_t arm_smmu_unmap(struct iommu_domain *domain, unsigned long iova,
> >   			     size_t size)
> >   {
> > -	struct io_pgtable_ops *ops = to_smmu_domain(domain)->pgtbl_ops;
> > +	struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
> > +	struct io_pgtable_ops *ops = smmu_domain->pgtbl_ops;
> > +	size_t ret;
> >   
> >   	if (!ops)
> >   		return 0;
> >   
> > -	return ops->unmap(ops, iova, size);
> > +	pm_runtime_get_sync(smmu_domain->smmu->dev);
> Can these map/unmap ops be called from an atomic context? I seem
> to recall that being a problem before.

That's something which was dropped in the following patch merged in master:
523d7423e21b iommu/arm-smmu: Remove io-pgtable spinlock

Looks like we don't  need locks here anymore?

Best Regards
Vivek

> > +	ret = ops->unmap(ops, iova, size);
> > +	pm_runtime_put_sync(smmu_domain->smmu->dev);
> > +
> > +	return ret;
> >   }
> >   
> >   static phys_addr_t arm_smmu_iova_to_phys_hard(struct iommu_domain *domain,

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