Re: [lwip-users] LwIP RAW - Simultaneous (full-duplex) communication

[Nenad Pekez]

> And from which context are timers processed?

Xilinx timers are used. Each 250ms timer callback is called inside which 
TcpFastTmrFlag (for 250ms) and/or TcpSlowTmrFlag (for 500ms) variables 
are set to 1. In the main loop, there is this:

    while (1) {
        if (TcpFastTmrFlag) {
            tcp_fasttmr();
            TcpFastTmrFlag = 0;
        }
        if (TcpSlowTmrFlag) {
            tcp_slowtmr();
            TcpSlowTmrFlag = 0;
        }
        xemacif_input(echo_netif);
        transfer_txperf_data();
    }

Inside of timer callbacks, there is some SW workaround for HW bug of 
Ethernet controller:
    /* For providing an SW alternative for the SI #692601. Under heavy
     * Rx traffic if at some point the Rx path becomes unresponsive, the
     * following API call will ensures a SW reset of the Rx path. The
     * API xemacpsif_resetrx_on_no_rxdata is called every 100 milliseconds.
     * This ensures that if the above HW bug is hit, in the worst case,
     * the Rx path cannot become unresponsive for more than 100
     * milliseconds.
     */
#ifndef USE_SOFTETH_ON_ZYNQ
    if (ResetRxCntr >= RESET_RX_CNTR_LIMIT) {
        xemacpsif_resetrx_on_no_rxdata(echo_netif);
        ResetRxCntr = 0;
    }
#endif

I don't think any calls to lwIP are made from an ISR.