[PATCH v3 12/16] iommu/amd: Add support for different types of PPR handler

[Vasant Hegde <vasant.hegde@amd.com>]

From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>

For AMD IOMMU, the PPR feature is needed to support IO page fault (IOPF).
PPR is enabled per PCI end-point device, and is configured by the PPR bit
in the IOMMU device table entry (i.e DTE[PPR]).

Currently, PPR is enabled for a device when it is initialized for AMD
IOMMU v2API. To support paging for IOPF, the DTE[PPR] bit needs to be
updated when enable/disable IOPF feature.

Introducing struct iommu_dev_data.ppr and enum ppr_handlers to track PPR
setting for each device.

Finally iommu_dev_data.ppr is set only when IOMMU supports PPR. Hence
remove redundant feature support check in set_dte_entry().

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Co-developed-by: Vasant Hegde <vasant.hegde@amd.com>
Signed-off-by: Vasant Hegde <vasant.hegde@amd.com>
---
 drivers/iommu/amd/amd_iommu_types.h |  6 ++++++
 drivers/iommu/amd/iommu.c           | 10 ++++------
 drivers/iommu/amd/iommu_v2.c        | 14 +++++++++++++-
 3 files changed, 23 insertions(+), 7 deletions(-)

diff --git a/drivers/iommu/amd/amd_iommu_types.h b/drivers/iommu/amd/amd_iommu_types.h
index b79c6e10684d..443b13b56235 100644
--- a/drivers/iommu/amd/amd_iommu_types.h
+++ b/drivers/iommu/amd/amd_iommu_types.h
@@ -803,6 +803,11 @@ struct devid_map {
 	bool cmd_line;
 };
 
+enum ppr_handlers {
+	PPR_HANDLER_NONE,	/* No handler specified */
+	PPR_HANDLER_V2API,	/* IOMMU v2 API ppr handler */
+};
+
 /*
  * This struct contains device specific data for the IOMMU
  */
@@ -820,6 +825,7 @@ struct iommu_dev_data {
 	u8 ats_enabled  :1;		  /* ATS state */
 	u8 pri_tlp      :1;		  /* PASID TLB required for
 					     PPR completions */
+	enum ppr_handlers ppr;
 	bool use_vapic;			  /* Enable device to use vapic mode */
 	bool defer_attach;
 
diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 5968eb8d265c..888bce5abe56 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -1634,10 +1634,8 @@ static void set_dte_entry(struct amd_iommu *iommu, u16 devid,
 	if (ats)
 		flags |= DTE_FLAG_IOTLB;
 
-	if (ppr) {
-		if (iommu_feature(iommu, FEATURE_EPHSUP))
-			pte_root |= 1ULL << DEV_ENTRY_PPR;
-	}
+	if (ppr)
+		pte_root |= 1ULL << DEV_ENTRY_PPR;
 
 	if (domain->flags & PD_IOMMUV2_MASK) {
 		u64 gcr3 = iommu_virt_to_phys(domain->gcr3_tbl);
@@ -1730,7 +1728,7 @@ static void do_attach(struct iommu_dev_data *dev_data,
 
 	/* Update device table */
 	set_dte_entry(iommu, dev_data->devid, domain,
-		      ats, dev_data->iommu_v2);
+		      ats, dev_data->ppr);
 	clone_aliases(iommu, dev_data->dev);
 
 	device_flush_dte(dev_data);
@@ -2009,7 +2007,7 @@ static void update_device_table(struct protection_domain *domain)
 		if (!iommu)
 			continue;
 		set_dte_entry(iommu, dev_data->devid, domain,
-			      dev_data->ats_enabled, dev_data->iommu_v2);
+			      dev_data->ats_enabled, dev_data->ppr);
 		clone_aliases(iommu, dev_data->dev);
 	}
 }
diff --git a/drivers/iommu/amd/iommu_v2.c b/drivers/iommu/amd/iommu_v2.c
index 9bf114382c00..4148cbf069dc 100644
--- a/drivers/iommu/amd/iommu_v2.c
+++ b/drivers/iommu/amd/iommu_v2.c
@@ -740,6 +740,10 @@ int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
 	unsigned long flags;
 	int ret, tmp;
 	u32 sbdf;
+	struct iommu_dev_data *dev_data = dev_iommu_priv_get(&pdev->dev);
+
+	if (!dev_data)
+		return -ENODEV;
 
 	might_sleep();
 
@@ -762,6 +766,9 @@ int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
 	if (dev_state == NULL)
 		return -ENOMEM;
 
+	/* Enable device for PPR support */
+	dev_data->ppr = PPR_HANDLER_V2API;
+
 	spin_lock_init(&dev_state->lock);
 	init_waitqueue_head(&dev_state->wq);
 	dev_state->pdev  = pdev;
@@ -832,6 +839,8 @@ int amd_iommu_init_device(struct pci_dev *pdev, int pasids)
 out_free_dev_state:
 	kfree(dev_state);
 
+	dev_data->ppr = PPR_HANDLER_NONE;
+
 	return ret;
 }
 EXPORT_SYMBOL(amd_iommu_init_device);
@@ -841,8 +850,9 @@ void amd_iommu_free_device(struct pci_dev *pdev)
 	struct device_state *dev_state;
 	unsigned long flags;
 	u32 sbdf;
+	struct iommu_dev_data *dev_data = dev_iommu_priv_get(&pdev->dev);
 
-	if (!amd_iommu_v2_supported())
+	if (!dev_data || !amd_iommu_v2_supported())
 		return;
 
 	sbdf = get_pci_sbdf_id(pdev);
@@ -859,6 +869,8 @@ void amd_iommu_free_device(struct pci_dev *pdev)
 
 	spin_unlock_irqrestore(&state_lock, flags);
 
+	dev_data->ppr = PPR_HANDLER_NONE;
+
 	put_device_state(dev_state);
 	free_device_state(dev_state);
 }
-- 
2.31.1