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Devlink Params¶

devlink provides capability for a driver to expose device parameters for low level device functionality. Since devlink can operate at the device-wide level, it can be used to provide configuration that may affect multiple ports on a single device.

This document describes a number of generic parameters that are supported across multiple drivers. Each driver is also free to add their own parameters. Each driver must document the specific parameters they support, whether generic or not.

Configuration modes¶

Parameters may be set in different configuration modes.

Possible configuration modes¶
Name Description
runtime set while the driver is running, and takes effect immediately. No reset is required.
driverinit applied while the driver initializes. Requires the user to restart the driver using the devlink reload command.
permanent written to the device’s non-volatile memory. A hard reset is required for it to take effect.

Reloading¶

In order for driverinit parameters to take effect, the driver must support reloading via the devlink-reload command. This command will request a reload of the device driver.

Generic configuration parameters¶

The following is a list of generic configuration parameters that drivers may add. Use of generic parameters is preferred over each driver creating their own name.

List of generic parameters¶
Name Type Description
enable_sriov Boolean Enable Single Root I/O Virtualization (SRIOV) in the device.
ignore_ari Boolean Ignore Alternative Routing-ID Interpretation (ARI) capability. If enabled, the adapter will ignore ARI capability even when the platform has support enabled. The device will create the same number of partitions as when the platform does not support ARI.
msix_vec_per_pf_max u32 Provides the maximum number of MSI-X interrupts that a device can create. Value is the same across all physical functions (PFs) in the device.
msix_vec_per_pf_min u32 Provides the minimum number of MSI-X interrupts required for the device to initialize. Value is the same across all physical functions (PFs) in the device.
fw_load_policy u8
Control the device’s firmware loading policy.
  • DEVLINK_PARAM_FW_LOAD_POLICY_VALUE_DRIVER (0) Load firmware version preferred by the driver.
  • DEVLINK_PARAM_FW_LOAD_POLICY_VALUE_FLASH (1) Load firmware currently stored in flash.
  • DEVLINK_PARAM_FW_LOAD_POLICY_VALUE_DISK (2) Load firmware currently available on host’s disk.
reset_dev_on_drv_probe u8
Controls the device’s reset policy on driver probe.
  • DEVLINK_PARAM_RESET_DEV_ON_DRV_PROBE_VALUE_UNKNOWN (0) Unknown or invalid value.
  • DEVLINK_PARAM_RESET_DEV_ON_DRV_PROBE_VALUE_ALWAYS (1) Always reset device on driver probe.
  • DEVLINK_PARAM_RESET_DEV_ON_DRV_PROBE_VALUE_NEVER (2) Never reset device on driver probe.
  • DEVLINK_PARAM_RESET_DEV_ON_DRV_PROBE_VALUE_DISK (3) Reset the device only if firmware can be found in the filesystem.
enable_roce Boolean Enable handling of RoCE traffic in the device.
internal_err_reset Boolean When enabled, the device driver will reset the device on internal errors.
max_macs u32 Specifies the maximum number of MAC addresses per ethernet port of this device.
region_snapshot_enable Boolean Enable capture of devlink-region snapshots.

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