• Anton Vorontsov's avatar
    gianfar: Revive the driver for eTSEC devices (disable timestamping) · 619baba1
    Anton Vorontsov authored
    Since commit cc772ab7 ("gianfar: Add
    hardware RX timestamping support"), the driver no longer works on
    at least MPC8313ERDB and MPC8568EMDS boards (and possibly much more
    boards as well).
    
    That's how MPC8313 Reference Manual describes RCTRL_TS_ENABLE bit:
    
      Timestamp incoming packets as padding bytes. PAL field is set
      to 8 if the PAL field is programmed to less than 8. Must be set
      to zero if TMR_CTRL[TE]=0.
    
    I see that the commit above sets this bit, but it doesn't handle
    TMR_CTRL. Manfred probably had this bit set by the firmware for
    his boards. But obviously this isn't true for all boards in the
    wild.
    
    Also, I recall that Freescale BSPs were explicitly disabling the
    timestamping because of a performance drop.
    
    For now, the best way to deal with this is just disable the
    timestamping, and later we can discuss proper device tree bindings
    and implement enabling this feature via some property.
    Signed-off-by: default avatarAnton Vorontsov <avorontsov@mvista.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    619baba1
gianfar.c 83.9 KB