Re: [RESEND PATCH v17 2/5] iommu/arm-smmu: Invoke pm_runtime during probe, add/remove device

[Vivek Gautam]

Hi Will,

On Wed, Nov 21, 2018 at 11:09 PM Will Deacon <will.deacon@xxxxxxx> wrote:
>
> On Fri, Nov 16, 2018 at 04:54:27PM +0530, Vivek Gautam wrote:
> > From: Sricharan R <sricharan@xxxxxxxxxxxxxx>
> >
> > The smmu device probe/remove and add/remove master device callbacks
> > gets called when the smmu is not linked to its master, that is without
> > the context of the master device. So calling runtime apis in those places
> > separately.
> > Global locks are also initialized before enabling runtime pm as the
> > runtime_resume() calls device_reset() which does tlb_sync_global()
> > that ultimately requires locks to be initialized.
> >
> > Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx>
> > [vivek: Cleanup pm runtime calls]
> > Signed-off-by: Vivek Gautam <vivek.gautam@xxxxxxxxxxxxxx>
> > Reviewed-by: Tomasz Figa <tfiga@xxxxxxxxxxxx>
> > Tested-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
> > Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx>
> > ---
> >  drivers/iommu/arm-smmu.c | 101 ++++++++++++++++++++++++++++++++++++++++++-----
> >  1 file changed, 91 insertions(+), 10 deletions(-)
>
> Given that you're doing the get/put in the TLBI ops unconditionally:
>
> >  static void arm_smmu_flush_iotlb_all(struct iommu_domain *domain)
> >  {
> >       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
> > +     struct arm_smmu_device *smmu = smmu_domain->smmu;
> >
> > -     if (smmu_domain->tlb_ops)
> > +     if (smmu_domain->tlb_ops) {
> > +             arm_smmu_rpm_get(smmu);
> >               smmu_domain->tlb_ops->tlb_flush_all(smmu_domain);
> > +             arm_smmu_rpm_put(smmu);
> > +     }
> >  }
> >
> >  static void arm_smmu_iotlb_sync(struct iommu_domain *domain)
> >  {
> >       struct arm_smmu_domain *smmu_domain = to_smmu_domain(domain);
> > +     struct arm_smmu_device *smmu = smmu_domain->smmu;
> >
> > -     if (smmu_domain->tlb_ops)
> > +     if (smmu_domain->tlb_ops) {
> > +             arm_smmu_rpm_get(smmu);
> >               smmu_domain->tlb_ops->tlb_sync(smmu_domain);
> > +             arm_smmu_rpm_put(smmu);
> > +     }
>
> Why do you need them around the map/unmap calls as well?

We still have .tlb_add_flush path?

Thanks
Vivek
>
> Will
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