• Or Gerlitz's avatar
    mlx4_core: Allow dynamic MTU configuration for IB ports · 096335b3
    Or Gerlitz authored
    Set the MTU for IB ports in the driver instead of using the firmware
    default of 2KB (the driver defaults to 4KB).  Allow for dynamic mtu
    configuration through a new, per-port sysfs entry.
    
    Since there's a dependency between the port MTU and the max number of
    HW VLs the port can support, apply a mim/max approach, using a loop
    that goes down from the highest possible number of VLs to the lowest,
    using the firmware return status to know whether the requested number
    of VLs is possible with a given MTU.
    
    For now, as with the dynamic link type change / VPI support, the sysfs
    entry to change the mtu is exposed only when NOT running in SR-IOV
    mode.  To allow changing the MTU for the master in SR-IOV mode,
    primary-function-initiated FLR (Function Level Reset) needs to be
    implemented.
    Signed-off-by: default avatarOr Gerlitz <ogerlitz@mellanox.com>
    Signed-off-by: default avatarRoland Dreier <roland@purestorage.com>
    096335b3
port.c 24.1 KB