Device-tree declares whether a PCI root-complex supports ATS by setting the "ats-supported" property. Copy this flag into device fwspec to let IOMMU drivers quickly check if they can enable ATS for a device. Tested-by: Ketan Patil <ketanp@xxxxxxxxxx> Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Reviewed-by: Liviu Dudau <liviu.dudau@xxxxxxx> Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx> Reviewed-by: Nicolin Chen <nicolinc@xxxxxxxxxx> Signed-off-by: Jean-Philippe Brucker <jean-philippe@xxxxxxxxxx> --- drivers/iommu/of_iommu.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/iommu/of_iommu.c b/drivers/iommu/of_iommu.c index 3afe0b48a48db..082b94c2b3291 100644 --- a/drivers/iommu/of_iommu.c +++ b/drivers/iommu/of_iommu.c @@ -105,6 +105,14 @@ static int of_iommu_configure_device(struct device_node *master_np, of_iommu_configure_dev(master_np, dev); } +static void of_pci_check_device_ats(struct device *dev, struct device_node *np) +{ + struct iommu_fwspec *fwspec = dev_iommu_fwspec_get(dev); + + if (fwspec && of_property_read_bool(np, "ats-supported")) + fwspec->flags |= IOMMU_FWSPEC_PCI_RC_ATS; +} + /* * Returns: * 0 on success, an iommu was configured @@ -147,6 +155,7 @@ int of_iommu_configure(struct device *dev, struct device_node *master_np, pci_request_acs(); err = pci_for_each_dma_alias(to_pci_dev(dev), of_pci_iommu_init, &info); + of_pci_check_device_ats(dev, master_np); } else { err = of_iommu_configure_device(master_np, dev, id); } -- 2.45.2