Commit 52efdb89 authored by Joerg Roedel's avatar Joerg Roedel
Browse files

iommu/amd: Add amd_iommu_device_info() function 



This function can be used to find out which features
necessary for IOMMUv2 usage are available on a given device.

Signed-off-by: default avatarJoerg Roedel <joerg.roedel@amd.com>
parent 46277b75

drivers/iommu/amd_iommu.c

+43 −0
Original line number Diff line number Diff line
@@ -3565,3 +3565,46 @@ void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum) 
	dev_data->errata |= (1 << erratum);

}

EXPORT_SYMBOL(amd_iommu_enable_device_erratum);



int amd_iommu_device_info(struct pci_dev *pdev,

                          struct amd_iommu_device_info *info)

{

	int max_pasids;

	int pos;



	if (pdev == NULL || info == NULL)

		return -EINVAL;



	if (!amd_iommu_v2_supported())

		return -EINVAL;



	memset(info, 0, sizeof(*info));



	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_ATS);

	if (pos)

		info->flags |= AMD_IOMMU_DEVICE_FLAG_ATS_SUP;



	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);

	if (pos)

		info->flags |= AMD_IOMMU_DEVICE_FLAG_PRI_SUP;



	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);

	if (pos) {

		int features;



		max_pasids = 1 << (9 * (amd_iommu_max_glx_val + 1));

		max_pasids = min(max_pasids, (1 << 20));



		info->flags |= AMD_IOMMU_DEVICE_FLAG_PASID_SUP;

		info->max_pasids = min(pci_max_pasids(pdev), max_pasids);



		features = pci_pasid_features(pdev);

		if (features & PCI_PASID_CAP_EXEC)

			info->flags |= AMD_IOMMU_DEVICE_FLAG_EXEC_SUP;

		if (features & PCI_PASID_CAP_PRIV)

			info->flags |= AMD_IOMMU_DEVICE_FLAG_PRIV_SUP;

	}



	return 0;

}

EXPORT_SYMBOL(amd_iommu_device_info);

include/linux/amd-iommu.h

+26 −0
Original line number Diff line number Diff line
@@ -119,6 +119,32 @@ typedef int (*amd_iommu_invalid_ppr_cb)(struct pci_dev *pdev, 
extern int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,

					amd_iommu_invalid_ppr_cb cb);



/**

 * amd_iommu_device_info() - Get information about IOMMUv2 support of a

 *			     PCI device

 * @pdev: PCI device to query information from

 * @info: A pointer to an amd_iommu_device_info structure which will contain

 *	  the information about the PCI device

 *

 * Returns 0 on success, negative value on error

 */



#define AMD_IOMMU_DEVICE_FLAG_ATS_SUP     0x1    /* ATS feature supported */

#define AMD_IOMMU_DEVICE_FLAG_PRI_SUP     0x2    /* PRI feature supported */

#define AMD_IOMMU_DEVICE_FLAG_PASID_SUP   0x4    /* PASID context supported */

#define AMD_IOMMU_DEVICE_FLAG_EXEC_SUP    0x8    /* Device may request execution

						    on memory pages */

#define AMD_IOMMU_DEVICE_FLAG_PRIV_SUP   0x10    /* Device may request

						    super-user privileges */



struct amd_iommu_device_info {

	int max_pasids;

	u32 flags;

};



extern int amd_iommu_device_info(struct pci_dev *pdev,

				 struct amd_iommu_device_info *info);



#else



static inline int amd_iommu_detect(void) { return -ENODEV; }