/* ethhandler.c - ethhandler */

#include 

/*------------------------------------------------------------------------
 * ethhandler - TI AM335X Ethernet Interrupt Handler
 *------------------------------------------------------------------------
 */
interrupt ethhandler (
                uint32  xnum                    /* IRQ number           */
        )
{
        struct  eth_a_csreg *csrptr;            /* Ethernet CSR pointer */
        struct  eth_a_tx_desc *tdescptr;        /* Tx desc pointer      */
        struct  eth_a_rx_desc *rdescptr;        /* Rx desc pointer      */
        struct  ethcblk *ethptr = ðertab[0]; /* Ethernet ctl blk ptr */

        csrptr = (struct eth_a_csreg *)ethptr->csr;

        if(xnum == ETH_AM335X_TXINT) {  /* Transmit interrupt */

                /* Get pointer to first desc in queue   */

                tdescptr = (struct eth_a_tx_desc *)ethptr->txRing +
                                                        ethptr->txHead;

                /* Defer scheduling until all descs are processed */

                resched_cntl(DEFER_START);

                while(semcount(ethptr->osem) < (int32)ethptr->txRingSize) {

                        /* If desc owned by DMA, check if we need to    */
                        /* Restart the transmission                     */

                        if(tdescptr->stat & ETH_AM335X_TDS_OWN) {
                                if(csrptr->stateram->tx_hdp[0] == 0) {
                                        csrptr->stateram->tx_hdp[0] =
                                                        (uint32)tdescptr;
                                }
                                break;
                        }

                        /* Acknowledge the interrupt    */

                        csrptr->stateram->tx_cp[0] = (uint32)tdescptr;

                        /* Increment the head index of the queue        */
                        /* And go to the next descriptor in queue       */

                        ethptr->txHead++;
                        tdescptr++;
                        if(ethptr->txHead >= ethptr->txRingSize) {
                                ethptr->txHead = 0;
                                tdescptr = (struct eth_a_tx_desc *)
                                                        ethptr->txRing;
                        }

                        /* Signal the output semaphore */

                        signal(ethptr->osem);
                }

                /* Acknowledge the transmit interrupt */

                csrptr->cpdma->eoi_vector = 0x2;

                /* Resume rescheduling  */

                resched_cntl(DEFER_STOP);
        }
        else if(xnum == ETH_AM335X_RXINT) {     /* Receive interrupt */

                /* Get the pointer to last desc in the queue    */

                rdescptr = (struct eth_a_rx_desc *)ethptr->rxRing +
                                                        ethptr->rxTail;

                /* Defer scheduling until all descriptors are processed */

                resched_cntl(DEFER_START);

                while(semcount(ethptr->isem) < (int32)ethptr->rxRingSize) {

                        /* Check if we need to restart the DMA  */

                        if(rdescptr->stat & ETH_AM335X_RDS_OWN) {
                                if(csrptr->stateram->rx_hdp[0] == 0) {
                                        csrptr->stateram->rx_hdp[0] =
                                                        (uint32)rdescptr;
                                }
                                break;
                        }

                        /* Acknowledge the interrupt    */

                        csrptr->stateram->rx_cp[0] = (uint32)rdescptr;

                        /* Increment the tail index of the queue        */
                        /* And go to the next descriptor in the queue   */

                        ethptr->rxTail++;
                        rdescptr++;
                        if(ethptr->rxTail >= ethptr->rxRingSize) {
                                ethptr->rxTail = 0;
                                rdescptr = (struct eth_a_rx_desc *)
                                                        ethptr->rxRing;
                        }

                        /* Signal the input semaphore   */

                        signal(ethptr->isem);
                }

                /* Acknowledge the receive interrupt */

                csrptr->cpdma->eoi_vector = 0x1;

                /* Resume rescheduling  */

                resched_cntl(DEFER_STOP);
        }
}