iommu/amd: Remove the unused device errata code

The device errata mechism is entirely unused, so remove it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210402143312.372386-2-hch@lst.deSigned-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd/amd_iommu_types.h

@@ -693,7 +693,6 @@ struct iommu_dev_data {
 	} ats;				  /* ATS state */
 	bool pri_tlp;			  /* PASID TLB required for
 					     PPR completions */
-	u32 errata;			  /* Bitmap for errata to apply */
 	bool use_vapic;			  /* Enable device to use vapic mode */
 	bool defer_attach;
 

drivers/iommu/amd/iommu.c

@@ -290,15 +290,6 @@ static bool pci_iommuv2_capable(struct pci_dev *pdev)
 	return true;
 }
 
-static bool pdev_pri_erratum(struct pci_dev *pdev, u32 erratum)
-{
-	struct iommu_dev_data *dev_data;
-
-	dev_data = dev_iommu_priv_get(&pdev->dev);
-
-	return dev_data->errata & (1 << erratum) ? true : false;
-}
-
 /*
  * This function checks if the driver got a valid device from the caller to
  * avoid dereferencing invalid pointers.
@@ -1531,33 +1522,9 @@ static void pdev_iommuv2_disable(struct pci_dev *pdev)
 	pci_disable_pasid(pdev);
 }
 
-/* FIXME: Change generic reset-function to do the same */
-static int pri_reset_while_enabled(struct pci_dev *pdev)
-{
-	u16 control;
-	int pos;
-
-	pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
-	if (!pos)
-		return -EINVAL;
-
-	pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
-	control |= PCI_PRI_CTRL_RESET;
-	pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
-
-	return 0;
-}
-
 static int pdev_iommuv2_enable(struct pci_dev *pdev)
 {
-	bool reset_enable;
-	int reqs, ret;
-
-	/* FIXME: Hardcode number of outstanding requests for now */
-	reqs = 32;
-	if (pdev_pri_erratum(pdev, AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE))
-		reqs = 1;
-	reset_enable = pdev_pri_erratum(pdev, AMD_PRI_DEV_ERRATUM_ENABLE_RESET);
+	int ret;
 
 	/* Only allow access to user-accessible pages */
 	ret = pci_enable_pasid(pdev, 0);
@@ -1570,16 +1537,11 @@ static int pdev_iommuv2_enable(struct pci_dev *pdev)
 		goto out_err;
 
 	/* Enable PRI */
-	ret = pci_enable_pri(pdev, reqs);
+	/* FIXME: Hardcode number of outstanding requests for now */
+	ret = pci_enable_pri(pdev, 32);
 	if (ret)
 		goto out_err;
 
-	if (reset_enable) {
-		ret = pri_reset_while_enabled(pdev);
-		if (ret)
-			goto out_err;
-	}
-
 	ret = pci_enable_ats(pdev, PAGE_SHIFT);
 	if (ret)
 		goto out_err;
@@ -2594,18 +2556,6 @@ struct iommu_domain *amd_iommu_get_v2_domain(struct pci_dev *pdev)
 }
 EXPORT_SYMBOL(amd_iommu_get_v2_domain);
 
-void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum)
-{
-	struct iommu_dev_data *dev_data;
-
-	if (!amd_iommu_v2_supported())
-		return;
-
-	dev_data = dev_iommu_priv_get(&pdev->dev);
-	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)
 {

include/linux/amd-iommu.h

@@ -32,24 +32,6 @@ struct pci_dev;
 extern int amd_iommu_detect(void);
 extern int amd_iommu_init_hardware(void);
 
-/**
- * amd_iommu_enable_device_erratum() - Enable erratum workaround for device
- *				       in the IOMMUv2 driver
- * @pdev: The PCI device the workaround is necessary for
- * @erratum: The erratum workaround to enable
- *
- * The function needs to be called before amd_iommu_init_device().
- * Possible values for the erratum number are for now:
- * - AMD_PRI_DEV_ERRATUM_ENABLE_RESET - Reset PRI capability when PRI
- *					is enabled
- * - AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE - Limit number of outstanding PRI
- *					 requests to one
- */
-#define AMD_PRI_DEV_ERRATUM_ENABLE_RESET		0
-#define AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE		1
-
-extern void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum);
-
 /**
  * amd_iommu_init_device() - Init device for use with IOMMUv2 driver
  * @pdev: The PCI device to initialize