Commit 24b6c779 authored by Yicong Yang's avatar Yicong Yang Committed by Mathieu Poirier
Browse files

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



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

Acked-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarYicong Yang <yangyicong@hisilicon.com>
Reviewed-by: default avatarJohn Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/20220816114414.4092-2-yangyicong@huawei.com


Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
parent 269e633d

drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c

+21 −0
Original line number Diff line number Diff line
@@ -2817,6 +2817,26 @@ static int arm_smmu_dev_disable_feature(struct device *dev, 
	}

}



/*

 * HiSilicon PCIe tune and trace device can be used to trace TLP headers on the

 * PCIe link and save the data to memory by DMA. The hardware is restricted to

 * use identity mapping only.

 */

#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,
@@ -2831,6 +2851,7 @@ 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,

	.default_domain_ops = &(const struct iommu_domain_ops) {