Enable PASID for PCI devices that support it. Since the SSID tables are allocated by arm_smmu_attach_dev(), PASID has to be enabled early enough. arm_smmu_dev_feature_enable() would be too late, since by that time the main DMA domain has already been attached. Do it in add_device() instead.
Signed-off-by: Jean-Philippe Brucker <[email protected]> --- drivers/iommu/arm-smmu-v3.c | 51 ++++++++++++++++++++++++++++++++++++- 1 file changed, 50 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index 972bfb80f964..a8a516d9ff10 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -2197,6 +2197,49 @@ static void arm_smmu_disable_ats(struct arm_smmu_master *master) master->ats_enabled = false; } +static int arm_smmu_enable_pasid(struct arm_smmu_master *master) +{ + int ret; + int features; + int num_pasids; + struct pci_dev *pdev; + + if (!dev_is_pci(master->dev)) + return -ENOSYS; + + pdev = to_pci_dev(master->dev); + + features = pci_pasid_features(pdev); + if (features < 0) + return -ENOSYS; + + num_pasids = pci_max_pasids(pdev); + if (num_pasids <= 0) + return -ENOSYS; + + ret = pci_enable_pasid(pdev, features); + if (!ret) + master->ssid_bits = min_t(u8, ilog2(num_pasids), + master->smmu->ssid_bits); + return ret; +} + +static void arm_smmu_disable_pasid(struct arm_smmu_master *master) +{ + struct pci_dev *pdev; + + if (!dev_is_pci(master->dev)) + return; + + pdev = to_pci_dev(master->dev); + + if (!pdev->pasid_enabled) + return; + + pci_disable_pasid(pdev); + master->ssid_bits = 0; +} + static void arm_smmu_detach_dev(struct arm_smmu_master *master) { unsigned long flags; @@ -2413,6 +2456,9 @@ static int arm_smmu_add_device(struct device *dev) master->ssid_bits = min(smmu->ssid_bits, fwspec->num_pasid_bits); + /* Note that PASID must be enabled before, and disabled after ATS */ + arm_smmu_enable_pasid(master); + /* * If the SMMU doesn't support 2-stage CD, limit the linear * tables to a reasonable number of contexts, let's say @@ -2423,7 +2469,7 @@ static int arm_smmu_add_device(struct device *dev) ret = iommu_device_link(&smmu->iommu, dev); if (ret) - goto err_free_master; + goto err_disable_pasid; group = iommu_group_get_for_dev(dev); if (IS_ERR(group)) { @@ -2436,6 +2482,8 @@ static int arm_smmu_add_device(struct device *dev) err_unlink: iommu_device_unlink(&smmu->iommu, dev); +err_disable_pasid: + arm_smmu_disable_pasid(master); err_free_master: kfree(master); fwspec->iommu_priv = NULL; @@ -2456,6 +2504,7 @@ static void arm_smmu_remove_device(struct device *dev) arm_smmu_detach_dev(master); iommu_group_remove_device(dev); iommu_device_unlink(&smmu->iommu, dev); + arm_smmu_disable_pasid(master); kfree(master); iommu_fwspec_free(dev); } -- 2.21.0
