On Wed, Jan 8, 2014 at 2:19 PM, Roy Franz <roy.fr...@linaro.org> wrote:
> The 9118 ethernet controller supports transmission of multi-buffer packets
> with arbitrary byte alignment of the start and end bytes. All writes to
> the packet fifo are 32 bits, so the controller discards bytes at the beginning
> and end of each buffer based on the 'Data start offset' and 'Buffer size'
> of the TX command 'A' format.
>
> This patch changes the buffer size and offset internal state variables to be
> updated on every "TX command A" write. Previously they were only updated for
> the first segment, which resulted incorrect behavior for packets with more
> than one segment. Each segment of the packet has its own CMD A command, with
> its own buffer size and start offset.
>
> Also update extraction of fields from the CMD A word to use extract32().
>
> Signed-off-by: Roy Franz <roy.fr...@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwa...@xilinx.com>
> ---
> hw/net/lan9118.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c
> index 2315f99..bb0c503 100644
> --- a/hw/net/lan9118.c
> +++ b/hw/net/lan9118.c
> @@ -727,14 +727,14 @@ static void tx_fifo_push(lan9118_state *s, uint32_t val)
> s->txp->cmd_a = val & 0x831f37ff;
> s->txp->fifo_used++;
> s->txp->state = TX_B;
> + s->txp->buffer_size = extract32(s->txp->cmd_a, 0, 11);
> + s->txp->offset = extract32(s->txp->cmd_a, 16, 5);
> break;
> case TX_B:
> if (s->txp->cmd_a & 0x2000) {
> /* First segment */
> s->txp->cmd_b = val;
> s->txp->fifo_used++;
> - s->txp->buffer_size = s->txp->cmd_a & 0x7ff;
> - s->txp->offset = (s->txp->cmd_a >> 16) & 0x1f;
> /* End alignment does not include command words. */
> n = (s->txp->buffer_size + s->txp->offset + 3) >> 2;
> switch ((n >> 24) & 3) {
> --
> 1.7.10.4
>
>
