Commit 5e12d089 authored by Ido Schimmel's avatar Ido Schimmel Committed by David S. Miller
Browse files

mlxsw: pci: Implement PCI reset handlers 



Implement reset_prepare() and reset_done() handlers that are invoked by
the PCI core before and after issuing a PCI reset, respectively.

Specifically, implement reset_prepare() by calling
mlxsw_core_bus_device_unregister() and reset_done() by calling
mlxsw_core_bus_device_register(). This is the same implementation as the
reload_{down,up}() devlink operations with the following differences:

1. The devlink instance is unregistered and then registered again after
   the reset.

2. A reset via the device's command interface (using MRSR register) is
   not issued during reset_done() as PCI core already issued a PCI
   reset.

Tested:

 # for i in $(seq 1 10); do echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset; done

Reviewed-by: default avatarPetr Machata <petrm@nvidia.com>
Signed-off-by: default avatarIdo Schimmel <idosch@nvidia.com>
Signed-off-by: default avatarPetr Machata <petrm@nvidia.com>
Reviewed-by: default avatarSimon Horman <horms@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent f257c73e

drivers/net/ethernet/mellanox/mlxsw/pci.c

+28 −0
Original line number Diff line number Diff line
@@ -130,6 +130,7 @@ struct mlxsw_pci { 
	const struct pci_device_id *id;

	enum mlxsw_pci_cqe_v max_cqe_ver; /* Maximal supported CQE version */

	u8 num_sdq_cqs; /* Number of CQs used for SDQs */

	bool skip_reset;

};



static void mlxsw_pci_queue_tasklet_schedule(struct mlxsw_pci_queue *q)
@@ -1527,6 +1528,10 @@ mlxsw_pci_reset(struct mlxsw_pci *mlxsw_pci, const struct pci_device_id *id) 
		return err;

	}



	/* PCI core already issued a PCI reset, do not issue another reset. */

	if (mlxsw_pci->skip_reset)

		return 0;



	mlxsw_reg_mcam_pack(mcam_pl,

			    MLXSW_REG_MCAM_FEATURE_GROUP_ENHANCED_FEATURES);

	err = mlxsw_reg_query(mlxsw_pci->core, MLXSW_REG(mcam), mcam_pl);
@@ -2107,11 +2112,34 @@ static void mlxsw_pci_remove(struct pci_dev *pdev) 
	kfree(mlxsw_pci);

}



static void mlxsw_pci_reset_prepare(struct pci_dev *pdev)

{

	struct mlxsw_pci *mlxsw_pci = pci_get_drvdata(pdev);



	mlxsw_core_bus_device_unregister(mlxsw_pci->core, false);

}



static void mlxsw_pci_reset_done(struct pci_dev *pdev)

{

	struct mlxsw_pci *mlxsw_pci = pci_get_drvdata(pdev);



	mlxsw_pci->skip_reset = true;

	mlxsw_core_bus_device_register(&mlxsw_pci->bus_info, &mlxsw_pci_bus,

				       mlxsw_pci, false, NULL, NULL);

	mlxsw_pci->skip_reset = false;

}



static const struct pci_error_handlers mlxsw_pci_err_handler = {

	.reset_prepare = mlxsw_pci_reset_prepare,

	.reset_done = mlxsw_pci_reset_done,

};



int mlxsw_pci_driver_register(struct pci_driver *pci_driver)

{

	pci_driver->probe = mlxsw_pci_probe;

	pci_driver->remove = mlxsw_pci_remove;

	pci_driver->shutdown = mlxsw_pci_remove;

	pci_driver->err_handler = &mlxsw_pci_err_handler;

	return pci_register_driver(pci_driver);

}

EXPORT_SYMBOL(mlxsw_pci_driver_register);