On Fri, Dec 27, 2013 at 5:25 PM, Peter Crosthwaite
<peter.crosthwa...@xilinx.com> wrote:
> On Sat, Dec 21, 2013 at 4:26 AM, 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 uses the provided buffer length to limit the bytes transmitted.
>> Previously all the bytes of the last 32-bit word written to the TX fifo
>> were added to the internal transmit buffer structure resulting in more bytes
>> being transmitted than were submitted to the hardware in the command. This
>> resulted in extra bytes being inserted into the middle of multi-buffer
>> packets when the non-final buffers had non-32bit aligned ending addresses.
>>
>> Signed-off-by: Roy Franz <roy.fr...@linaro.org>
>> ---
>> hw/net/lan9118.c | 3 +--
>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>
>> diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c
>> index c5d6f14..712bb41 100644
>> --- a/hw/net/lan9118.c
>> +++ b/hw/net/lan9118.c
>> @@ -773,11 +773,10 @@ static void tx_fifo_push(lan9118_state *s, uint32_t
>> val)
>> in FIFO words. Empirical results show it to be
>> little-endian.
>> */
>> /* TODO: FIFO overflow checking. */
>> - while (n--) {
>> + while (n-- && s->txp->buffer_size--) {
>
> can you just get n right in the first place (line 766):
>
> n = MIN(4, s->txp_buffer_size);
>
> rather than doing min calculation on two parallel iteration variables?
>
> Regards,
> Peter
>
>> s->txp->data[s->txp->len] = val & 0xff;
>> s->txp->len++;
>> val >>= 8;
>> - s->txp->buffer_size--;
>> }
>> s->txp->fifo_used++;
>> }
>> --
>> 1.7.10.4
>>
>>
Hi Peter,
I'll take a look at this (and your other comments on the extract32)
when I am back at work next week.
Thanks,
Roy
