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
