On 2020/2/14 0:50, Jean-Philippe Brucker wrote: > Enable ATS on device-tree based systems, and factor the common ATS > enablement checks into pci_enable_ats(). > > ATS support in PCIe endpoints is discovered through the ATS capability, > but there is no common method for discovering whether the host bridge > supports ATS. Each vendor provides their own ACPI method: > * DMAR (Intel) reports ATS support per domain or per root port. > * IVRS (AMD) reports negative ATS support for a range of devices. > * IORT (ARM) reports ATS support for a root complex. Tested this patch set against 5.6-rc2 on a Kunpeng920 ARM server, I just confirmed that this patch set didn't break anything in my box with ACPI booting, PCI devices work as expected, FWIW, Tested-by: Hanjun Guo <guohanjun@xxxxxxxxxx> Thanks Hanjun