On Tue, May 12, 2020 at 12:08:29PM +0800, Zhangfei Gao wrote: > Some platform devices appear as PCI but are > actually on the AMBA bus, and they need fixup in > drivers/pci/quirks.c handling iommu_fwnode. > So calling pci_fixup_final after iommu_fwnode is allocated. > > For example: > Hisilicon platform device need fixup in > drivers/pci/quirks.c > > +static void quirk_huawei_pcie_sva(struct pci_dev *pdev) > +{ > + struct iommu_fwspec *fwspec; > + > + pdev->eetlp_prefix_path = 1; > + fwspec = dev_iommu_fwspec_get(&pdev->dev); > + if (fwspec) > + fwspec->can_stall = 1; > +} > + > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva); > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_HUAWEI, 0xa251, quirk_huawei_pcie_sva); I don't think it is a great idea to hook this into PCI_FIXUP_FINAL. The fixup list needs to be processed for every device, which will slow down probing. So either we introduce something like PCI_FIXUP_IOMMU, if this is entirely PCI specific. If it needs to be generic we need some fixup infrastructure in the IOMMU code itself. Regards, Joerg