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

[Heiko Stuebner]

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.


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));
>