Re: [PATCH v2 01/13] iommu/rockchip: Request irqs in rk_iommu_probe()

[JeffyChen]

Hi Robin,

On 01/17/2018 08:18 PM, Robin Murphy wrote:
> > @@ -91,7 +92,6 @@ struct rk_iommu {
> >       void __iomem **bases;
> >       int num_mmu;
> >       int *irq;
>
> Nit: irq seems to be redundant now as well.
oops, will fix it.
> > -    int num_irq;
> >       bool reset_disabled;
> >       struct iommu_device iommu;
> >       struct list_head node; /* entry in rk_iommu_domain.iommus */
> > @@ -830,13 +830,6 @@ static int rk_iommu_attach_device(struct
> > iommu_domain *domain,
> >       iommu->domain = domain;
> > -    for (i = 0; i < iommu->num_irq; i++) {
> > -        ret = devm_request_irq(iommu->dev, iommu->irq[i], rk_iommu_irq,
> > -                       IRQF_SHARED, dev_name(dev), iommu);
> > -        if (ret)
> > -            return ret;
> > -    }
> > -
> >       for (i = 0; i < iommu->num_mmu; i++) {
> >           rk_iommu_write(iommu->bases[i], RK_MMU_DTE_ADDR,
> >                      rk_domain->dt_dma);
> > @@ -885,9 +878,6 @@ static void rk_iommu_detach_device(struct
> > iommu_domain *domain,
> >       }
> >       rk_iommu_disable_stall(iommu);
> > -    for (i = 0; i < iommu->num_irq; i++)
> > -        devm_free_irq(iommu->dev, iommu->irq[i], iommu);
> > -
> >       iommu->domain = NULL;
> >       dev_dbg(dev, "Detached from iommu domain\n");
> > @@ -1138,7 +1128,7 @@ static int rk_iommu_probe(struct platform_device
> > *pdev)
> >       struct rk_iommu *iommu;
> >       struct resource *res;
> >       int num_res = pdev->num_resources;
> > -    int err, i;
> > +    int err, i, irq, num_irq;
> >       iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL);
> >       if (!iommu)
> > @@ -1165,23 +1155,17 @@ static int rk_iommu_probe(struct
> > platform_device *pdev)
> >       if (iommu->num_mmu == 0)
> >           return PTR_ERR(iommu->bases[0]);
> > -    iommu->num_irq = platform_irq_count(pdev);
> > -    if (iommu->num_irq < 0)
> > -        return iommu->num_irq;
> > -    if (iommu->num_irq == 0)
> > -        return -ENXIO;
> > -
> > -    iommu->irq = devm_kcalloc(dev, iommu->num_irq, sizeof(*iommu->irq),
> > -                  GFP_KERNEL);
> > -    if (!iommu->irq)
> > -        return -ENOMEM;
> > -
> > -    for (i = 0; i < iommu->num_irq; i++) {
> > -        iommu->irq[i] = platform_get_irq(pdev, i);
> > -        if (iommu->irq[i] < 0) {
> > -            dev_err(dev, "Failed to get IRQ, %d\n", iommu->irq[i]);
> > +    num_irq = of_irq_count(dev->of_node);
>
> To follow up on the other reply, I'm not sure you really need to count
> the IRQs beforehand at all - you're going to be looping through
> platform_get_irq() and handling errors anyway, so you may as well just
> start at 0 and keep going until -ENOENT (or use platform_get_resource()
> to double-check whether an index should be valid, as we do in arm_smmu).
ok, will do that.
> Otherwise, it looks like everything that the IRQ handler needs in the
> iommu struct (dev, num_mmu and bases) is already initialised by this
> point, so we should be OK with respect to races.
ok.
> Robin.