ena

NAME

ena — FreeBSD kernel driver for Elastic Network Adapter (ENA) family

SYNOPSIS

To compile this driver into the kernel, place the following line in the kernel configuration file:

device ena

Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

if_ena_load="YES"

DESCRIPTION

The ENA is a networking interface designed to make good use of modern CPU features and system architectures.

The ENA device exposes a lightweight management interface with a minimal set of memory mapped registers and extendable command set through an Admin Queue.

The driver supports a range of ENA devices, is link-speed independent (i.e., the same driver is used for 10GbE, 25GbE, 40GbE, etc.), and has a negotiated and extendable feature set.

Some ENA devices support SR-IOV. This driver is used for both the SR-IOV Physical Function (PF) and Virtual Function (VF) devices.

The ENA devices enable high speed and low overhead network traffic processing by providing multiple Tx/Rx queue pairs (the maximum number is advertised by the device via the Admin Queue), a dedicated MSI-X interrupt vector per Tx/Rx queue pair, and CPU cacheline optimized data placement.

The ena driver supports industry standard TCP/IP offload features such as checksum offload and TCP transmit segmentation offload (TSO). Receive-side scaling (RSS) is supported for multi-core scaling.

The ena driver and its corresponding devices implement health monitoring mechanisms such as watchdog, enabling the device and driver to recover in a manner transparent to the application, as well as debug logs.

Some of the ENA devices support a working mode called Low-latency Queue (LLQ), which saves several more microseconds. This feature will be implemented for driver in future releases.

HARDWARE

Supported PCI vendor ID/device IDs:

1d0f:0ec2 - ENA PF
1d0f:1ec2 - ENA PF with LLQ support
1d0f:ec20 - ENA VF
1d0f:ec21 - ENA VF with LLQ support

DIAGNOSTICS

Device initialization phase:

ena%d: failed to init mmio read less: Error occurred during initialization of the mmio register read request.
ena%d: Can not reset device: Device could not be reset.

Device may not be responding or is already during reset.
ena%d: device version is too low: Version of the controller is too old and it is not supported by the driver.
ena%d: Invalid dma width value %d: The controller is able to request dma transaction width.

Device stopped responding or it demanded invalid value.
ena%d: Can not initialize ena admin queue with device: Initialization of the Admin Queue failed.

Device may not be responding or there was a problem with initialization of the resources.
ena%d: Cannot get attribute for ena device rc: %d: Failed to get attributes of the device from the controller.
ena%d: Cannot configure aenq groups rc: %d: Errors occurred when trying to configure AENQ groups.

Driver initialisation/shutdown phase:

ena%d: PCI resource allocation failed!
ena%d: allocating ena_dev failed
ena%d: failed to pmap registers bar
ena%d: Error while setting up bufring
ena%d: Error with initialization of IO rings
ena%d: can not allocate ifnet structure
ena%d: Error with network interface setup
ena%d: Failed to enable and set the admin interrupts
ena%d: Failed to allocate %d, vectors %d
ena%d: Failed to enable MSIX, vectors %d rc %d
ena%d: Error with MSI-X enablement
ena%d: could not allocate irq vector: %d
ena%d: Unable to allocate bus resource: registers: Resource allocation failed when initializing the device.

Driver will not be attached.
ena%d: ENA device init failed (err: %d): Device initialization failed.

Driver will not be attached.
ena%d: could not activate irq vector: %d: Error occurred when trying to activate interrupt vectors for Admin Queue.
ena%d: failed to register interrupt handler for irq %ju: %d: Error occurred when trying to register Admin Queue interrupt handler.
ena%d: Cannot setup mgmnt queue intr: Error occurred during configuration of the Admin Queue interrupts.
ena%d: Enable MSI-X failed: Configuration of the MSI-X for Admin Queue failed.

There could be lack of resources or interrupts could not have been configured.

Driver will not be attached.
ena%d: VLAN is in use, detach first: VLANs are being used when trying to detach the driver.

VLANs must be detached first and then detach routine have to be called again.
ena%d: Unmapped RX DMA tag associations
ena%d: Unmapped TX DMA tag associations: Error occurred when trying to destroy RX/TX DMA tag.
ena%d: Cannot init RSS
ena%d: Cannot fill indirect table
ena%d: Cannot fill indirect table
ena%d: Cannot fill hash function
ena%d: Cannot fill hash control
ena%d: WARNING: RSS was not properly initialized, it will affect bandwidth: Error occurred during initialization of one of RSS resources.

The device will work with reduced performance because all RX packets will be passed to queue 0 and there will be no hash information.
ena%d: failed to tear down irq: %d
ena%d: dev has no parent while releasing res for irq: %d: Release of the interrupts failed.

Additional diagnostic:

ena%d: Cannot get attribute for ena device: This message appears when trying to change MTU and driver is unable to get attributes from the device.
ena%d: Invalid MTU setting. new_mtu: %d: Requested MTU value is not supported and will not be set.
ena%d: keep alive watchdog timeout: Device stopped responding and will be reset.
ena%d: Found a Tx that wasn't completed on time, qid %d, index %d.: Packet was pushed to the NIC but not sent within given time limit.

It may be caused by hang of the IO queue.
ena%d: The number of lost tx completion is aboce the threshold (%d > %d). Reset the device: If too many Tx wasn't completed on time the device is going to be reset.

It may be caused by hanged queue or device.
ena%d: trigger reset is on: Device will be reset.

Reset is triggered either by watchdog or if too many TX packets were not completed on time.
ena%d: invalid value recvd: Link status received from the device in the AENQ handler is invalid.
ena%d: Allocation for Tx Queue %u failed
ena%d: Allocation for Rx Queue %u failed
ena%d: Unable to create Rx DMA map for buffer %d
ena%d: Failed to create io TX queue #%d rc: %d
ena%d: Failed to get TX queue handlers. TX queue num %d rc: %d
ena%d: Failed to create io RX queue[%d] rc: %d
ena%d: Failed to get RX queue handlers. RX queue num %d rc: %d
ena%d: failed to request irq
ena%d: could not allocate irq vector: %d
ena%d: failed to register interrupt handler for irq %ju: %d: IO resources initialization failed.

Interface will not be brought up.
ena%d: LRO[%d] Initialization failed!: Initialization of the LRO for the RX ring failed.
ena%d: failed to alloc buffer for rx queue
ena%d: failed to add buffer for rx queue %d
ena%d: refilled rx queue %d with %d pages only: Allocation of resources used on RX path failed.

If happened during initialization of the IO queue, the interface will not be brought up.
ena%d: ioctl promisc/allmulti: IOCTL request for the device to work in promiscuous/allmulti mode.

See ifconfig(8) for more details.
ena%d: too many fragments. Last fragment: %d!: Packet with unsupported number of segments was queued for sending to the device.

Packet will be dropped.

SUPPORT

If an issue is identified with the released source code with a supported adapter, please email the specific information related to the issue to <[email protected]> and <[email protected]>.

AUTHORS

The ena driver was written by Semihalf.

August 16, 2017

Debian