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.

Property dma-can-stall depends on patchset
https://lore.kernel.org/linux-iommu/20210302092644.2553014-1-jean-phili...@linaro.org/

Signed-off-by: Zhangfei Gao <zhangfei....@linaro.org>
Signed-off-by: Jean-Philippe Brucker <jean-phili...@linaro.org>
Signed-off-by: Zhou Wang <wangzh...@hisilicon.com>
---
 drivers/pci/quirks.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 873d27f..b866cdf 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -1827,10 +1827,23 @@ DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_VENDOR_ID_HUAWEI, 
0x1610, PCI_CLASS_BRIDGE_PCI
 
 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);
-- 
2.9.5

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