Message ID | 1589256511-12446-1-git-send-email-zhangfei.gao@linaro.org (mailing list archive) |
---|---|
Headers | show |
Series | Let pci_fixup_final access iommu_fwnode | expand |
Hi, Joerg On 2020/5/12 下午12:08, 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); > > > Zhangfei Gao (2): > iommu/of: Let pci_fixup_final access iommu_fwnode > ACPI/IORT: Let pci_fixup_final access iommu_fwnode > > drivers/acpi/arm64/iort.c | 1 + > drivers/iommu/of_iommu.c | 1 + > 2 files changed, 2 insertions(+) > Would you mind give any suggestion? We need access fwspec->can_stall describing the platform device (a fake pcie) can support stall feature. can_stall will be used arm_smmu_add_device [1]. And stall is not a pci feature, so no such member in struct pci_dev. iommu_fwnode is allocated in iommu_fwspec_init, from of_pci_iommu_init or iort_pci_iommu_init. The pci_fixup_device(pci_fixup_final, dev) in pci_bus_add_device is too early that iommu_fwnode is not allocated. The pci_fixup_device(pci_fixup_enable, dev) in do_pci_enable_device is too late after arm_smmu_add_device. So the idea here is calling pci_fixup_device(pci_fixup_final) after of_pci_iommu_init and iort_pci_iommu_init, where iommu_fwnode is allocated. [1] https://www.spinics.net/lists/linux-pci/msg94559.html Thanks
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
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