Re: [PATCH V2 2/3] iommu/rockchip: add multi irqs support

[xxm]

Hi Heiko,


On 07/21/2017 03:07 PM, Heiko Stuebner wrote:
> Am Freitag, 21. Juli 2017, 14:27:09 CEST schrieb Simon Xue:
> > From: Simon <xxm@xxxxxxxxxxxxxx>
> >
> > RK3368 vpu mmu have two irqs, this patch support multi irqs
> >
> > Signed-off-by: Simon <xxm@xxxxxxxxxxxxxx>
> > ---
> > changes since V1:
> >   - use devm_kcalloc instead of devm_kzalloc when alloc irq array
> >
> >   drivers/iommu/rockchip-iommu.c | 34 ++++++++++++++++++++++++----------
> >   1 file changed, 24 insertions(+), 10 deletions(-)
> >
> > diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c
> > index 4ba48a2..3c462c0 100644
> > --- a/drivers/iommu/rockchip-iommu.c
> > +++ b/drivers/iommu/rockchip-iommu.c
> > @@ -90,7 +90,8 @@ struct rk_iommu {
> >   	struct device *dev;
> >   	void __iomem **bases;
> >   	int num_mmu;
> > -	int irq;
> > +	int *irq;
> > +	int num_irq;
> >   	struct iommu_device iommu;
> >   	struct list_head node; /* entry in rk_iommu_domain.iommus */
> >   	struct iommu_domain *domain; /* domain to which iommu is attached */
> > @@ -825,10 +826,12 @@ static int rk_iommu_attach_device(struct iommu_domain *domain,
> >   
> >   	iommu->domain = domain;
> >   
> > -	ret = devm_request_irq(iommu->dev, iommu->irq, rk_iommu_irq,
> > -			       IRQF_SHARED, dev_name(dev), iommu);
> > -	if (ret)
> > -		return ret;
> > +	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,
> > @@ -878,7 +881,8 @@ static void rk_iommu_detach_device(struct iommu_domain *domain,
> >   	}
> >   	rk_iommu_disable_stall(iommu);
> >   
> > -	devm_free_irq(iommu->dev, iommu->irq, iommu);
> > +	for (i = 0; i < iommu->num_irq; i++)
> > +		devm_free_irq(iommu->dev, iommu->irq[i], iommu);
> >   
> >   	iommu->domain = NULL;
> >   
> > @@ -1157,10 +1161,20 @@ static int rk_iommu_probe(struct platform_device *pdev)
> >   	if (iommu->num_mmu == 0)
> >   		return PTR_ERR(iommu->bases[0]);
> >   
> > -	iommu->irq = platform_get_irq(pdev, 0);
> > -	if (iommu->irq < 0) {
> > -		dev_err(dev, "Failed to get IRQ, %d\n", iommu->irq);
> > -		return -ENXIO;
> > +	while (platform_get_irq(pdev, iommu->num_irq) >= 0)
> > +		iommu->num_irq++;
> Hmm, this could also result in a iommu having 0 irqs if wrongly
> configured and probe would still suceed. This sounds somehow
> wrong to me.
>
> But I'm not sure if there is precedent on how to handle a variable
> number of interrupts correctly somewhere.

How about add a judgement for iommu->num_irq ? like this:
if (!iommu->num_irq)
	return -ENOXIO;

> Heiko
>
> > +
> > +	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]);
> > +			return -ENXIO;
> > +		}
> >   	}
> >   
> >   	err = iommu_device_sysfs_add(&iommu->iommu, dev, NULL, dev_name(dev));