[PATCH v3 8/8] iommu/arm-smmu-v3: Make default domain type of HiSilicon PTT device to identity

[Yicong Yang]

The DMA of HiSilicon PTT device can only work with identical
mapping. So add a quirk for the device to force the domain
passthrough.

Signed-off-by: Yicong Yang <yangyicong@xxxxxxxxxxxxx>
---
 drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 6dc6d8b6b368..6f67a2b1dd27 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -2838,6 +2838,21 @@ static int arm_smmu_dev_disable_feature(struct device *dev,
 	}
 }
 
+#define IS_HISI_PTT_DEVICE(pdev)	((pdev)->vendor == PCI_VENDOR_ID_HUAWEI && \
+					 (pdev)->device == 0xa12e)
+
+static int arm_smmu_def_domain_type(struct device *dev)
+{
+	if (dev_is_pci(dev)) {
+		struct pci_dev *pdev = to_pci_dev(dev);
+
+		if (IS_HISI_PTT_DEVICE(pdev))
+			return IOMMU_DOMAIN_IDENTITY;
+	}
+
+	return 0;
+}
+
 static struct iommu_ops arm_smmu_ops = {
 	.capable		= arm_smmu_capable,
 	.domain_alloc		= arm_smmu_domain_alloc,
@@ -2863,6 +2878,7 @@ static struct iommu_ops arm_smmu_ops = {
 	.sva_unbind		= arm_smmu_sva_unbind,
 	.sva_get_pasid		= arm_smmu_sva_get_pasid,
 	.page_response		= arm_smmu_page_response,
+	.def_domain_type	= arm_smmu_def_domain_type,
 	.pgsize_bitmap		= -1UL, /* Restricted during device attach */
 	.owner			= THIS_MODULE,
 };
-- 
2.24.0