On 2020/5/25 下午9:43, Joerg Roedel wrote:
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.
Thanks Joerg for the good suggestion. I am trying to introduce PCI_FIXUP_IOMMU in https://lkml.org/lkml/2020/5/26/366 Thanks
