• Niklas Cassel's avatar
    net: stmmac: set total length of the packet to be transmitted in TDES3 · fe6af0e1
    Niklas Cassel authored
    Field FL/TPL in register TDES3 is not correctly set on GMAC4.
    TX appears to be functional on GMAC 4.10a even if this field is not set,
    however, to avoid relying on undefined behavior, set the length in TDES3.
    
    The field has a different meaning depending on if the TSE bit in TDES3
    is set or not (TSO). However, regardless of the TSE bit, the field is
    not optional. The field is already set correctly when the TSE bit is set.
    
    Since there is no limit for the number of descriptors that can be
    used for a single packet, the field should be set to the sum of
    the buffers contained in:
    [<desc with First Descriptor bit set> ... <desc n> ...
    <desc with Last Descriptor bit set>], which should be equal to skb->len.
    Signed-off-by: default avatarNiklas Cassel <niklas.cassel@axis.com>
    Acked-by: default avatarGiuseppe Cavallaro <peppe.cavallaro@st.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    fe6af0e1
chain_mode.c 5.34 KB