diff options
| -rw-r--r-- | drivers/pci/quirks.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 5d46ac697218..1871c1de4e75 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -1821,12 +1821,37 @@ DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_E7525_MCH, quir DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_HUAWEI, 0x1610, PCI_CLASS_BRIDGE_PCI, 8, quirk_pcie_mch); +/* + * HiSilicon KunPeng920 and KunPeng930 have devices appear as PCI but are + * actually on the AMBA bus. These fake PCI devices can support SVA via + * SMMU stall feature, by setting dma-can-stall for ACPI platforms. + * + * Normally stalling must not be enabled for PCI devices, since it would + * break the PCI requirement for free-flowing writes and may lead to + * deadlock. We expect PCI devices to support ATS and PRI if they want to + * be fault-tolerant, so there's no ACPI binding to describe anything else, + * even when a "PCI" device turns out to be a regular old SoC device + * dressed up as a RCiEP and normal rules don't apply. + */ static void quirk_huawei_pcie_sva(struct pci_dev *pdev) { + struct property_entry properties[] = { + PROPERTY_ENTRY_BOOL("dma-can-stall"), + {}, + }; + if (pdev->revision != 0x21 && pdev->revision != 0x30) return; pdev->pasid_no_tlp = 1; + + /* + * Set the dma-can-stall property on ACPI platforms. Device tree + * can set it directly. + */ + if (!pdev->dev.of_node && + device_add_properties(&pdev->dev, properties)) + pci_warn(pdev, "could not add stall property"); } 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); |