crypto: qat - centralize bus master enable

commit e5712ff upstream.

QAT driver currently toggles PCI bus mastering in multiple places
(probe paths, and reset callbacks). This makes BME state depend on
call ordering and on what PCI command bits were captured in saved PCI
config state.

Make BME control explicit and deterministic:
- remove pci_set_master() from device-specific probe paths
- add adf_set_bme() and call it from adf_dev_init() so BME is enabled
  at one point before device bring-up
- drop redundant pci_set_master() and pci_clear_master from adf_aer.c
  and rely on the unified init path for BME enablement

This is in preparation for adding reset_prepare() and reset_done()
hooks. In the PCI reset callback flow, the PCI core saves and
restores device configuration state around reset_prepare() and
reset_done(). This change is needed to ensure that we are able to
properly shutdown or reinitialize the device post sysfs triggered
resets.

Cc: stable@vger.kernel.org
Signed-off-by: Ahsan Atta <ahsan.atta@intel.com>
Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Suggested-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Ahsan-Atta

drivers/crypto/intel/qat/qat_420xx/adf_drv.c

@@ -146,8 +146,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		}
 	}
 
-	pci_set_master(pdev);
-
 	if (pci_save_state(pdev)) {
 		dev_err(&pdev->dev, "Failed to save pci state.\n");
 		ret = -ENOMEM;

drivers/crypto/intel/qat/qat_4xxx/adf_drv.c

@@ -148,8 +148,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		}
 	}
 
-	pci_set_master(pdev);
-
 	if (pci_save_state(pdev)) {
 		dev_err(&pdev->dev, "Failed to save pci state.\n");
 		ret = -ENOMEM;

drivers/crypto/intel/qat/qat_6xxx/adf_drv.c

@@ -162,8 +162,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 		}
 	}
 
-	pci_set_master(pdev);
-
 	/*
 	 * The PCI config space is saved at this point and will be restored
 	 * after a Function Level Reset (FLR) as the FLR does not completely

drivers/crypto/intel/qat/qat_c3xxx/adf_drv.c

@@ -167,7 +167,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 			goto out_err_free_reg;
 		}
 	}
-	pci_set_master(pdev);
 
 	if (pci_save_state(pdev)) {
 		dev_err(&pdev->dev, "Failed to save pci state\n");

drivers/crypto/intel/qat/qat_c3xxxvf/adf_drv.c

@@ -163,7 +163,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 			goto out_err_free_reg;
 		}
 	}
-	pci_set_master(pdev);
 	/* Completion for VF2PF request/response message exchange */
 	init_completion(&accel_dev->vf.msg_received);
 

drivers/crypto/intel/qat/qat_c62x/adf_drv.c

@@ -167,7 +167,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 			goto out_err_free_reg;
 		}
 	}
-	pci_set_master(pdev);
 
 	if (pci_save_state(pdev)) {
 		dev_err(&pdev->dev, "Failed to save pci state\n");

drivers/crypto/intel/qat/qat_c62xvf/adf_drv.c

@@ -163,7 +163,6 @@ static int adf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 			goto out_err_free_reg;
 		}
 	}
-	pci_set_master(pdev);
 	/* Completion for VF2PF request/response message exchange */
 	init_completion(&accel_dev->vf.msg_received);
 

drivers/crypto/intel/qat/qat_common/adf_aer.c

@@ -41,7 +41,6 @@ static pci_ers_result_t adf_error_detected(struct pci_dev *pdev,
 	adf_error_notifier(accel_dev);
 	adf_pf2vf_notify_fatal_error(accel_dev);
 	adf_dev_restarting_notify(accel_dev);
-	pci_clear_master(pdev);
 	adf_dev_down(accel_dev);
 
 	return PCI_ERS_RESULT_NEED_RESET;
@@ -106,6 +105,13 @@ void adf_dev_restore(struct adf_accel_dev *accel_dev)
 	}
 }
 
+void adf_set_bme(struct adf_accel_dev *accel_dev)
+{
+	struct pci_dev *pdev = accel_to_pci_dev(accel_dev);
+
+	pci_set_master(pdev);
+}
+
 static void adf_device_sriov_worker(struct work_struct *work)
 {
 	struct adf_sriov_dev_data *sriov_data =
@@ -198,8 +204,6 @@ static pci_ers_result_t adf_slot_reset(struct pci_dev *pdev)
 		return PCI_ERS_RESULT_DISCONNECT;
 	}
 
-	if (!pdev->is_busmaster)
-		pci_set_master(pdev);
 	pci_restore_state(pdev);
 	res = adf_dev_up(accel_dev, false);
 	if (res && res != -EALREADY)

drivers/crypto/intel/qat/qat_common/adf_common_drv.h

@@ -84,6 +84,7 @@ extern const struct pci_error_handlers adf_err_handler;
 void adf_reset_sbr(struct adf_accel_dev *accel_dev);
 void adf_reset_flr(struct adf_accel_dev *accel_dev);
 void adf_dev_restore(struct adf_accel_dev *accel_dev);
+void adf_set_bme(struct adf_accel_dev *accel_dev);
 int adf_init_aer(void);
 void adf_exit_aer(void);
 int adf_init_arb(struct adf_accel_dev *accel_dev);

drivers/crypto/intel/qat/qat_common/adf_init.c

@@ -73,6 +73,8 @@ static int adf_dev_init(struct adf_accel_dev *accel_dev)
 		return -EFAULT;
 	}
 
+	adf_set_bme(accel_dev);
+
 	if (!test_bit(ADF_STATUS_CONFIGURED, &accel_dev->status) &&
 	    !accel_dev->is_vf) {
 		dev_err(&GET_DEV(accel_dev), "Device not configured\n");