Messages in this thread | | | Subject | Re: [PATCH v1 6/9] iommu/tegra: gart: Ignore devices without IOMMU phandle in DT | From | Robin Murphy <> | Date | Fri, 11 May 2018 12:34:08 +0100 |
| |
Hi Dmitry,
On 08/05/18 19:16, Dmitry Osipenko wrote: > GART can't handle all devices, ignore devices that aren't related to GART. > Device tree must explicitly assign GART IOMMU to the devices. > > Signed-off-by: Dmitry Osipenko <digetx@gmail.com> > --- > drivers/iommu/tegra-gart.c | 33 ++++++++++++++++++++++++++++++++- > 1 file changed, 32 insertions(+), 1 deletion(-) > > diff --git a/drivers/iommu/tegra-gart.c b/drivers/iommu/tegra-gart.c > index 39305224c48d..5b2d27620350 100644 > --- a/drivers/iommu/tegra-gart.c > +++ b/drivers/iommu/tegra-gart.c > @@ -366,6 +366,26 @@ static void gart_iommu_remove_device(struct device *dev) > iommu_device_unlink(&gart_handle->iommu, dev); > } > > +static int gart_iommu_check_device(struct gart_device *gart, > + struct device *dev); > + > +struct iommu_group *gart_iommu_device_group(struct device *dev) > +{ > + int err; > + > + err = gart_iommu_check_device(gart_handle, dev); > + if (err) > + return ERR_PTR(err); > + > + return generic_device_group(dev); > +} > + > +static int gart_iommu_of_xlate(struct device *dev, > + struct of_phandle_args *args) > +{ > + return 0; > +} > + > static const struct iommu_ops gart_iommu_ops = { > .capable = gart_iommu_capable, > .domain_alloc = gart_iommu_domain_alloc, > @@ -374,14 +394,24 @@ static const struct iommu_ops gart_iommu_ops = { > .detach_dev = gart_iommu_detach_dev, > .add_device = gart_iommu_add_device, > .remove_device = gart_iommu_remove_device, > - .device_group = generic_device_group, > + .device_group = gart_iommu_device_group, > .map = gart_iommu_map, > .map_sg = default_iommu_map_sg, > .unmap = gart_iommu_unmap, > .iova_to_phys = gart_iommu_iova_to_phys, > .pgsize_bitmap = GART_IOMMU_PGSIZES, > + .of_xlate = gart_iommu_of_xlate, > }; > > +static int gart_iommu_check_device(struct gart_device *gart, > + struct device *dev) > +{ > + if (!dev->iommu_fwspec || dev->iommu_fwspec->ops != &gart_iommu_ops) > + return -ENODEV;
Conceptually, it would be better to verify this in .add_device *before* calling iommu_group_get_for_dev(). That would also align with what other drivers do, and let you save introducing the .device_group callback until the real implementation in the later patch.
Robin.
> + > + return 0; > +} > + > static int tegra_gart_suspend(struct device *dev) > { > struct gart_device *gart = dev_get_drvdata(dev); > @@ -462,6 +492,7 @@ static int tegra_gart_probe(struct platform_device *pdev) > } > > iommu_device_set_ops(&gart->iommu, &gart_iommu_ops); > + iommu_device_set_fwnode(&gart->iommu, dev->fwnode); > > ret = iommu_device_register(&gart->iommu); > if (ret) { >
| |