Hi,
This patch relates to mostly performance related changes.
1. Fixed incorrect computation of PANIC level in rx_buffer_level().
2. Removed unnecessary PIOs(read/write of tx_traffic_int and
   rx_traffic_int) from interrupt handler and removed read of
   general_int_status register from xmit routine.
3. Enable two-buffer mode(for Rx path) automatically for SGI
   systems. This improves Rx performance dramatically on
   SGI systems.
Signed-off-by: NRavinandan Arakali <ravinandan.arakali@neterion.com>
Signed-off-by: NRaghavendra Koushik <raghavendra.koushik@neterion.com>
Signed-off-by: NJeff Garzik <jgarzik@pobox.com>