On 24/01/2022 13:11, Yicong Yang wrote:
The DMA of HiSilicon PTT device can only work with identical
mapping. So add a quirk for the device to force the domain
passthrough.
This patch should be earlier in the series, before the PTT driver, and
the comment on hisi_ptt_check_iommu_mapping() should mention what is
going on here.
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)
I assume that not all revisions will require this check, right?
+
+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,
};
