Re: [PATCH 01/04] iommu/ipmmu-vmsa: Use iommu_device_register()/unregister()

[Robin Murphy]

On 15/06/17 11:29, Magnus Damm wrote:
> From: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>
> 
> Extend the driver to make use of iommu_device_register()/unregister()
> functions together with iommu_device_set_ops() and iommu_set_fwnode().
> 
> These used to be part of the earlier posted 64-bit ARM (r8a7795) series but
> it turns out that these days they are required on 32-bit ARM as well.
> 
> Signed-off-by: Magnus Damm <damm+renesas@xxxxxxxxxxxxx>
> ---
> 
>  drivers/iommu/ipmmu-vmsa.c |   10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> --- 0001/drivers/iommu/ipmmu-vmsa.c
> +++ work/drivers/iommu/ipmmu-vmsa.c	2017-06-15 16:57:21.890607110 +0900
> @@ -35,6 +35,7 @@
>  struct ipmmu_vmsa_device {
>  	struct device *dev;
>  	void __iomem *base;
> +	struct iommu_device iommu;
>  	struct list_head list;
>  
>  	unsigned int num_utlbs;
> @@ -1054,6 +1055,13 @@ static int ipmmu_probe(struct platform_d
>  
>  	ipmmu_device_reset(mmu);
>  
> +	ret = iommu_device_register(&mmu->iommu);
> +	if (ret)
> +		return ret;
> +
> +	iommu_device_set_ops(&mmu->iommu, &ipmmu_ops);
> +	iommu_device_set_fwnode(&mmu->iommu, &pdev->dev.of_node->fwnode);

Nit: I guess it works out OK in practice, but it does look rather weird
to be initialising the iommu_device's members *after* registering it.

Robin.

> +
>  	/*
>  	 * We can't create the ARM mapping here as it requires the bus to have
>  	 * an IOMMU, which only happens when bus_set_iommu() is called in
> @@ -1077,6 +1085,8 @@ static int ipmmu_remove(struct platform_
>  	list_del(&mmu->list);
>  	spin_unlock(&ipmmu_devices_lock);
>  
> +	iommu_device_unregister(&mmu->iommu);
> +
>  #if defined(CONFIG_ARM) && !defined(CONFIG_IOMMU_DMA)
>  	arm_iommu_release_mapping(mmu->mapping);
>  #endif
>