net_nic.c

uC/OS-II下的LPC2378集成以太网控制器的驱动

             MAC2      &=  ~MAC2_FULL_DUPLEX;                           /* Configure the EMAC to run in HALF duplex mode            */
             COMMAND   &=  ~COMMAND_FULL_DUPLEX;                        /* Configure the MII logic for a Half Duplex PHY Link       */
             IPGT       =   IPG_HALF_DUP;	                            /* Set inter packet gap to the recommended Half Duplex      */
             break;

        case NET_PHY_DUPLEX_FULL:
             MAC2      |=   MAC2_FULL_DUPLEX;                           /* Configure the EMAC to run in FULL duplex mode            */
             COMMAND   |=   COMMAND_FULL_DUPLEX;                        /* Configure the MII logic for a Full Duplex PHY Link       */
             IPGT       =   IPG_FULL_DUP;	                            /* Set inter packet gap to the recommended Full Duplex      */
             break;
    }
}

/*
*********************************************************************************************************
*                                         NetNIC_ISR_Handler()
*
* Description : (1) Decode ISR & call appropriate ISR handler :
*
*                   (a) Receive Buffer Not Available ISR     NetNIC_RxPktDiscard().
*                   (b) Receive  ISR                         NetNIC_RxISR_Handler().
*                   (c) Transmit ISR                         NetNIC_TxISR_Handler().
*
* Argument(s) : none.
*
* Return(s)   : none.
*
* Caller(s)   : This is an ISR
*
* Note(s)     : 1) VIC interrupts do not need to be explicity acknowledged if the BSP exception
*                  handler writes a 0x00 to the VICAddress register after calling the ISR handler.
*                  User ISR handlers (such as this one) need only clear the local interrupt source.
*********************************************************************************************************
*/

void  NetNIC_ISR_Handler (void)
{
    CPU_INT32U  intstatus;
    CPU_INT16U  n_new;
    NET_ERR     err;


    intstatus               =  INTSTATUS;                               /* Read the interrupt status register                       */

    if ((intstatus & INT_RX_DONE) > 0) {                                /* If a receiver event has occured                          */
        n_new               =  NIC_RxGetNRdy() - NIC_RxNRdyCtr;         /* Determine how many NEW franes have been received         */
        while (n_new > 0) {
            NetOS_IF_RxTaskSignal(&err);                                /* Signal Net IF Rx Task that a new frame has arrived       */
            switch (err) {                                              /* Each frame is processed sequentially from the Rx task    */
                case NET_IF_ERR_NONE:
                    if (NIC_RxNRdyCtr < EMAC_NUM_RX_DESC) {
                         NIC_RxNRdyCtr++;
                     }
                     break;

                case NET_IF_ERR_RX_Q_FULL:
                case NET_IF_ERR_RX_Q_POST_FAIL:
                default:
                     NetNIC_RxPktDiscard(0, &err);                      /* If an error occured while signaling the task, discard    */
                     break;                                             /* the received frame                                       */
            }

            n_new--;
        }
        INTCLEAR            = (INT_RX_DONE);                            /* Clear the interrupt flags                                */
    }

    if ((intstatus & (INT_RX_OVERRUN)) > 0) {                           /* If a fator Overrun error has occured                     */
        INTCLEAR            = (INT_RX_OVERRUN);                         /* Clear the overrun interrupt flag                         */
        COMMAND            |=  COMMAND_RESET_RX;                        /* Soft reset the Rx datapath, this disables the receiver   */
        COMMAND            |=  COMMAND_RX_EN;                           /* Re-enable the reciever                                   */
        MAC1               |=  MAC1_RX_ENABLE;                          /* Re-enable the reciever                                   */
    }
}

/*
*********************************************************************************************************
*                                         NetNIC_RxPktGetSize()
*
* Description : Get network packet size from NIC.
*
* Argument(s) : none.
*
* Return(s)   : Size, in octets, of next frame to be read from the EMAC buffers
*
* Caller(s)   : NetIF_RxTaskHandler()
*
* Notes       : None.
*********************************************************************************************************
*/

CPU_INT16U  NetNIC_RxPktGetSize (void)
{
    CPU_INT16S   size;
    CPU_INT32U   rxstatus;


    rxstatus        =  RxStatus[RXCONSUMEINDEX].StatusInfo;             /* Accquire the status word for this desciptor              */

    rxstatus       &= (RX_DESC_STATUS_NODESC    |                       /* Obtain the descriptor error bits                         */
                       RX_DESC_STATUS_OVERRUN   |
                       RX_DESC_STATUS_ALGNERR   |
                       RX_DESC_STATUS_LENERR    |
                       RX_DESC_STATUS_SYMERR    |
                       RX_DESC_STATUS_CRCERR    |
                       RX_DESC_STATUS_FAILFLT);

    if (rxstatus > 0) {                                                 /* If any receive errors (except range error) occured       */
        size        =  0;                                               /* then return 0 so upper layer call NetNIC_RxPktDiscard()  */
    } else {
        size        =  RxStatus[RXCONSUMEINDEX].StatusInfo & 0x7FF;     /* Obtain the fragment size from the status struct pointer  */
        size       -=  3;                                               /* +1 since the size is 0 based, -4 to ignore FCS           */
    }

    if (size < 0) {                                                     /* Ensure that the subtraction didnt cause an underflow     */
        size = 0;
    }

    return (size);                                                      /* Return the size of the current frame                     */
}

/*
*********************************************************************************************************
*                                            NetNIC_RxPkt()
*
* Description : Read network packet from NIC into buffer.
*
* Argument(s) : ppkt        Pointer to memory buffer to receive NIC packet.
*
*               size        Number of packet frame octets to read into buffer.
*
*               perr        Pointer to variable that will hold the return error code from this function :
*
*                               NET_NIC_ERR_NONE            Packet successfully read.
*                               NET_ERR_INIT_INCOMPLETE     Network initialization NOT complete.
*                               NET_NIC_ERR_NULL_PTR        Argument 'ppkt' passed a NULL pointer.
*                               NET_NIC_ERR_INVALID_SIZE    Invalid size.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_RxTaskHandler().
*
* Note(s)     : 1) NetNIC_RxPkt() blocked until network initialization completes; perform NO action.
*********************************************************************************************************
*/

void  NetNIC_RxPkt (void        *ppkt,
                    CPU_INT16U   size,
                    NET_ERR     *perr)
{
#if (NET_CTR_CFG_STAT_EN     == DEF_ENABLED)
#if (CPU_CFG_CRITICAL_METHOD == CPU_CRITICAL_METHOD_STATUS_LOCAL)
    CPU_SR   cpu_sr;
#endif
#endif


    if (Net_InitDone != DEF_YES) {                                      /* If init NOT complete, exit rx (see Note #2).         */
       *perr = NET_ERR_INIT_INCOMPLETE;
        return;
    }

#if (NET_ERR_CFG_ARG_CHK_DBG_EN == DEF_ENABLED)                         /* ------------------- VALIDATE PTR ------------------  */
    if (ppkt == (void *)0) {
       *perr = NET_NIC_ERR_NULL_PTR;
        return;
    }

                                                                        /* ------------------- VALIDATE SIZE -----------------  */
    if (size < NET_IF_FRAME_MIN_SIZE) {
       *perr = NET_NIC_ERR_INVALID_SIZE;
        return;
    }
#endif

    EMAC_RxPkt(ppkt, size, perr);                                       /* Read the received Frame from the EMAC buffers        */
    if (*perr != NET_NIC_ERR_NONE) {
        return;
    }

    NET_CTR_STAT_INC(NetNIC_StatRxPktCtr);

    *perr = NET_NIC_ERR_NONE;
}

/*
*********************************************************************************************************
*                                         NetNIC_RxPktDiscard()
*
* Description : Discard network packet from NIC to free NIC packet frames for new receive packets.
*
* Argument(s) : size        Number of packet frame octets.
*
*               perr        Pointer to variable that will hold the return error code from this function :
*
*                               NET_NIC_ERR_NONE            Packet successfully discarded.
*                               NET_ERR_INIT_INCOMPLETE     Network initialization NOT complete.
*
* Return(s)   : none.
*
* Caller(s)   : NetIF_RxTaskHandler().
*
* Note(s)     : (1) NetNIC_RxPktDiscard() blocked until network initialization completes; perform NO action.
*
*               (2) #### 'perr' may NOT be necessary (remove before product release if unnecessary).
*********************************************************************************************************
*/

void  NetNIC_RxPktDiscard (CPU_INT16U   size,
                           NET_ERR     *perr)
{
#if (CPU_CFG_CRITICAL_METHOD == CPU_CRITICAL_METHOD_STATUS_LOCAL)
    CPU_SR   cpu_sr;
#endif

    if (Net_InitDone != DEF_YES) {                                      /* If init NOT complete, exit discard (see Note #1).    */
       *perr = NET_ERR_INIT_INCOMPLETE;
        return;
    }

    EMAC_RxPktDiscard(size);

    CPU_CRITICAL_ENTER();                                               /* This routine alters shared data. Disable interrupts!     */
    if (NIC_RxNRdyCtr > 0) {                                            /* One less packet to process                               */
        NIC_RxNRdyCtr--;
    }
    CPU_CRITICAL_EXIT();                                                /* Re-Enable interrupts                                     */

    NET_CTR_ERR_INC(NetNIC_ErrRxPktDiscardedCtr);

   *perr = NET_NIC_ERR_NONE;
}

/*
*********************************************************************************************************
*                                             NetNIC_TxPkt()
*
* Description : Transmit data packets from network driver layer to network interface card.
*
* Argument(s) : ppkt        Pointer to memory buffer to transmit NIC packet.
*               ----        Argument validated in NetIF_Pkt_Tx().
*
*               size        Number of packet frame octets to write to frame.
*               ----        Argument checked   in NetIF_Tx().