TM4C129ENCPDT: Ethernet connection lost when disconnect/connect of wire - Link status

Hi,

  I don't think it was conclusive in the finding reported by the poster in the post you reference. As Amit (who is no longer with TM4C support) mentioned in the post, there is no issue with the link status during plug and unplug when running a stock TivaWare Ethernet example. Do you see the same issue as the referenced post? Did the workaround in that post solve the problem? As far as I tell, tivaif_process_phy_interrupt() in the latest TivaWare version has added support for EEE mode. Otherwise, it is much the same as the one pasted in that post. In the ISR, it first checks if there is a change to the LINK bit in the MISR1 register. If yes, check for whether the LINK bit is high or low in the STS register before passing the corresponding link info to the lwip stack. 

/**
 * Process interrupts from the PHY.
 *
 * should be called from the Stellaris Ethernet Interrupt Handler.  This
 * function will read packets from the Stellaris Ethernet fifo and place them
 * into a pbuf queue.  If the transmitter is idle and there is at least one packet
 * on the transmit queue, it will place it in the transmit fifo and start the
 * transmitter.
 *
 */
void
tivaif_process_phy_interrupt(struct netif *psNetif)
{
    uint16_t ui16Val, ui16Status;
#if EEE_SUPPORT
    uint16_t ui16EEEStatus;
#endif
    uint32_t ui32Config, ui32Mode, ui32RxMaxFrameSize;

    /* Read the PHY interrupt status.  This clears all interrupt sources.
     * Note that we are only enabling sources in EPHY_MISR1 so we don't
     * read EPHY_MISR2.
     */
    ui16Val = EMACPHYRead(EMAC0_BASE, PHY_PHYS_ADDR, EPHY_MISR1);

    /* Read the current PHY status. */
    ui16Status = EMACPHYRead(EMAC0_BASE, PHY_PHYS_ADDR, EPHY_STS);

    /* If EEE mode support is requested then read the value of the Link
     * partners status
     */
#if EEE_SUPPORT
    ui16EEEStatus = EMACPHYMMDRead(EMAC0_BASE, PHY_PHYS_ADDR, 0x703D);
#endif

    /* Has the link status changed? */
    if(ui16Val & EPHY_MISR1_LINKSTAT)
    {
        /* Is link up or down now? */
        if(ui16Status & EPHY_STS_LINK)
        {
            /* Tell lwIP the link is up. */
#if NO_SYS
            netif_set_link_up(psNetif);
#else
            tcpip_callback((tcpip_callback_fn)netif_set_link_up, psNetif);
#endif

            /* if the link has been advertised as EEE capable then configure
             * the MAC register for LPI timers and manually set the PHY link
             * status bit
             */
#if EEE_SUPPORT
            if(ui16EEEStatus & 0x2)
            {
                EMACLPIConfig(EMAC0_BASE, true, 1000, 36);
                EMACLPILinkSet(EMAC0_BASE);
                g_bEEELinkActive = true;
            }
#endif

            /* In this case we drop through since we may need to reconfigure
             * the MAC depending upon the speed and half/fui32l-duplex settings.
             */
        }
        else
        {
            /* Tell lwIP the link is down */
#if NO_SYS
            netif_set_link_down(psNetif);
#else
            tcpip_callback((tcpip_callback_fn)netif_set_link_down, psNetif);
#endif

            /* if the link has been advertised as EEE capable then clear the
             * MAC register LPI timers and manually clear the PHY link status
             * bit
             */
#if EEE_SUPPORT
           	g_bEEELinkActive = false;
           	EMACLPILinkClear(EMAC0_BASE);
           	EMACLPIConfig(EMAC0_BASE, false, 1000, 0);
#endif
        }
    }

    /* Has the speed or duplex status changed? */
    if(ui16Val & (EPHY_MISR1_SPEED | EPHY_MISR1_SPEED | EPHY_MISR1_ANC))
    {
        /* Get the current MAC configuration. */
        EMACConfigGet(EMAC0_BASE, &ui32Config, &ui32Mode,
                        &ui32RxMaxFrameSize);

        /* What speed is the interface running at now?
         */
        if(ui16Status & EPHY_STS_SPEED)
        {
            /* 10Mbps is selected */
            ui32Config &= ~EMAC_CONFIG_100MBPS;
        }
        else
        {
            /* 100Mbps is selected */
            ui32Config |= EMAC_CONFIG_100MBPS;
        }

        /* Are we in fui32l- or half-duplex mode? */
        if(ui16Status & EPHY_STS_DUPLEX)
        {
            /* Fui32l duplex. */
            ui32Config |= EMAC_CONFIG_FULL_DUPLEX;
        }
        else
        {
            /* Half duplex. */
            ui32Config &= ~EMAC_CONFIG_FULL_DUPLEX;
        }

        /* Reconfigure the MAC */
        EMACConfigSet(EMAC0_BASE, ui32Config, ui32Mode, ui32RxMaxFrameSize);
    }
}