Hello Stefano,
> On 26 Jan 2021, at 10:58 pm, Stefano Stabellini <sstabell...@kernel.org>
> wrote:
>
> From: Brian Woods <brian.wo...@xilinx.com>
>
> Now that all arm iommu drivers support generic bindings we can remove
> the workaround from iommu_add_dt_device().
>
> Note that if both legacy bindings and generic bindings are present in
> device tree, the legacy bindings are the ones that are used.
>
> Signed-off-by: Brian Woods <brian.wo...@xilinx.com>
> Signed-off-by: Stefano Stabellini <stefano.stabell...@xilinx.com>
Reviewed-by: Rahul Singh <rahul.si...@arm.com>
Tested-by: Rahul Singh <rahul.si...@arm.com>
Regards,
Rahul
> ---
> Changes in v3:
> - split patch
> - make find_smmu return non-const so that we can use it in
> arm_smmu_dt_add_device_generic
> - use dt_phandle_args
> - update commit message
> ---
> xen/drivers/passthrough/arm/smmu.c | 40 ++++++++++++++++++++++++++-
> xen/drivers/passthrough/device_tree.c | 17 +-----------
> 2 files changed, 40 insertions(+), 17 deletions(-)
>
> diff --git a/xen/drivers/passthrough/arm/smmu.c
> b/xen/drivers/passthrough/arm/smmu.c
> index 9687762283..620ba5a4b5 100644
> --- a/xen/drivers/passthrough/arm/smmu.c
> +++ b/xen/drivers/passthrough/arm/smmu.c
> @@ -254,6 +254,8 @@ struct iommu_group
> atomic_t ref;
> };
>
> +static struct arm_smmu_device *find_smmu(const struct device *dev);
> +
> static struct iommu_group *iommu_group_alloc(void)
> {
> struct iommu_group *group = xzalloc(struct iommu_group);
> @@ -843,6 +845,40 @@ static int register_smmu_master(struct arm_smmu_device
> *smmu,
> fwspec);
> }
>
> +static int arm_smmu_dt_add_device_generic(u8 devfn, struct device *dev)
> +{
> + struct arm_smmu_device *smmu;
> + struct iommu_fwspec *fwspec;
> +
> + fwspec = dev_iommu_fwspec_get(dev);
> + if (fwspec == NULL)
> + return -ENXIO;
> +
> + smmu = find_smmu(fwspec->iommu_dev);
> + if (smmu == NULL)
> + return -ENXIO;
> +
> + return arm_smmu_dt_add_device_legacy(smmu, dev, fwspec);
> +}
> +
> +static int arm_smmu_dt_xlate_generic(struct device *dev,
> + const struct dt_phandle_args *spec)
> +{
> + uint32_t mask, fwid = 0;
> +
> + if (spec->args_count > 0)
> + fwid |= (SMR_ID_MASK & spec->args[0]) << SMR_ID_SHIFT;
> +
> + if (spec->args_count > 1)
> + fwid |= (SMR_MASK_MASK & spec->args[1]) << SMR_MASK_SHIFT;
> + else if (!of_property_read_u32(spec->np, "stream-match-mask", &mask))
> + fwid |= (SMR_MASK_MASK & mask) << SMR_MASK_SHIFT;
> +
> + return iommu_fwspec_add_ids(dev,
> + &fwid,
> + 1);
> +}
> +
> static struct arm_smmu_device *find_smmu_for_device(struct device *dev)
> {
> struct arm_smmu_device *smmu;
> @@ -2766,6 +2802,7 @@ static void arm_smmu_iommu_domain_teardown(struct
> domain *d)
> static const struct iommu_ops arm_smmu_iommu_ops = {
> .init = arm_smmu_iommu_domain_init,
> .hwdom_init = arm_smmu_iommu_hwdom_init,
> + .add_device = arm_smmu_dt_add_device_generic,
> .teardown = arm_smmu_iommu_domain_teardown,
> .iotlb_flush = arm_smmu_iotlb_flush,
> .iotlb_flush_all = arm_smmu_iotlb_flush_all,
> @@ -2773,9 +2810,10 @@ static const struct iommu_ops arm_smmu_iommu_ops = {
> .reassign_device = arm_smmu_reassign_dev,
> .map_page = arm_iommu_map_page,
> .unmap_page = arm_iommu_unmap_page,
> + .dt_xlate = arm_smmu_dt_xlate_generic,
> };
>
> -static __init const struct arm_smmu_device *find_smmu(const struct device
> *dev)
> +static struct arm_smmu_device *find_smmu(const struct device *dev)
> {
> struct arm_smmu_device *smmu;
> bool found = false;
> diff --git a/xen/drivers/passthrough/device_tree.c
> b/xen/drivers/passthrough/device_tree.c
> index a51ae3c9c3..ae07f272e1 100644
> --- a/xen/drivers/passthrough/device_tree.c
> +++ b/xen/drivers/passthrough/device_tree.c
> @@ -162,22 +162,7 @@ int iommu_add_dt_device(struct dt_device_node *np)
> * these callback implemented.
> */
> if ( !ops->add_device || !ops->dt_xlate )
> - {
> - /*
> - * Some Device Trees may expose both legacy SMMU and generic
> - * IOMMU bindings together. However, the SMMU driver is only
> - * supporting the former and will protect them during the
> - * initialization. So we need to skip them and not return
> - * error here.
> - *
> - * XXX: This can be dropped when the SMMU is able to deal
> - * with generic bindings.
> - */
> - if ( dt_device_is_protected(np) )
> - return 0;
> - else
> - return -EINVAL;
> - }
> + return -EINVAL;
>
> if ( !dt_device_is_available(iommu_spec.np) )
> break;
> --
> 2.17.1
>
