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

From: Robin Murphy
Date: Mon Jun 19 2017 - 12:27:47 EST


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
>