diff options
| author | Yi Liu <yi.l.liu@intel.com> | 2025-03-21 11:01:42 -0700 |
|---|---|---|
| committer | Jason Gunthorpe <jgg@nvidia.com> | 2025-03-28 10:07:23 -0300 |
| commit | 803f97298e7de9242eb677a1351dcafbbcc9117e (patch) | |
| tree | 1a86d162a187ded29fb6f84916990e884fb760d8 /drivers/pci | |
| parent | ad744ed5dd8b70e9256fc1ff18aaaffeedf5f21e (diff) | |
iommufd: Extend IOMMU_GET_HW_INFO to report PASID capability
PASID usage requires PASID support in both device and IOMMU. Since the
iommu drivers always enable the PASID capability for the device if it
is supported, this extends the IOMMU_GET_HW_INFO to report the PASID
capability to userspace. Also, enhances the selftest accordingly.
Link: https://patch.msgid.link/r/20250321180143.8468-5-yi.l.liu@intel.com
Cc: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Tested-by: Zhangfei Gao <zhangfei.gao@linaro.org> #aarch64 platform
Tested-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/ats.c | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c index c6b266c772c8..ec6c8dbdc5e9 100644 --- a/drivers/pci/ats.c +++ b/drivers/pci/ats.c @@ -538,4 +538,37 @@ int pci_max_pasids(struct pci_dev *pdev) return (1 << FIELD_GET(PCI_PASID_CAP_WIDTH, supported)); } EXPORT_SYMBOL_GPL(pci_max_pasids); + +/** + * pci_pasid_status - Check the PASID status + * @pdev: PCI device structure + * + * Returns a negative value when no PASID capability is present. + * Otherwise the value of the control register is returned. + * Status reported are: + * + * PCI_PASID_CTRL_ENABLE - PASID enabled + * PCI_PASID_CTRL_EXEC - Execute permission enabled + * PCI_PASID_CTRL_PRIV - Privileged mode enabled + */ +int pci_pasid_status(struct pci_dev *pdev) +{ + int pasid; + u16 ctrl; + + if (pdev->is_virtfn) + pdev = pci_physfn(pdev); + + pasid = pdev->pasid_cap; + if (!pasid) + return -EINVAL; + + pci_read_config_word(pdev, pasid + PCI_PASID_CTRL, &ctrl); + + ctrl &= PCI_PASID_CTRL_ENABLE | PCI_PASID_CTRL_EXEC | + PCI_PASID_CTRL_PRIV; + + return ctrl; +} +EXPORT_SYMBOL_GPL(pci_pasid_status); #endif /* CONFIG_PCI_PASID */ |