if_edb7xxx.c

移植到WLIT项目的redboot源代码

// the hardware ready to send/receive packets.
//
static void
cs8900_start(struct eth_drv_sc *sc, unsigned char *enaddr, int flags)
{
    unsigned short stat;
    put_reg(PP_BusCtl, PP_BusCtl_MemoryE);  // Disable interrupts, memory mode
    put_reg(PP_IntReg, PP_IntReg_IRQ0);  // Only possibility
    put_reg(PP_RxCFG, PP_RxCFG_RxOK | PP_RxCFG_CRC | 
                      PP_RxCFG_RUNT | PP_RxCFG_EXTRA);
    put_reg(PP_RxCTL, PP_RxCTL_RxOK | PP_RxCTL_Broadcast | 
                      PP_RxCTL_IA);
    put_reg(PP_TxCFG, PP_TxCFG_TxOK | PP_TxCFG_Collision | 
                      PP_TxCFG_CRS | PP_TxCFG_SQE | PP_TxCFG_Late | 
                      PP_TxCFG_Jabber | PP_TxCFG_16Collisions);
    put_reg(PP_BufCFG, PP_BufCFG_TxRDY | PP_BufCFG_TxUE | PP_BufCFG_RxMiss | 
                       PP_BufCFG_TxCol | PP_BufCFG_Miss | PP_BufCFG_SWI);
    put_reg(PP_IntReg, PP_IntReg_IRQ0);  // Only possibility
    put_reg(PP_LineCTL, PP_LineCTL_Rx | PP_LineCTL_Tx);
    // Clear Interrupt Status Queue before enabling interrupts
    while ((stat = CS8900_ISQ) != 0) ;
    put_reg(PP_BusCtl, PP_BusCtl_EnableIRQ);
}

//
// This routine is called to perform special "control" opertions
//
static int
cs8900_control(struct eth_drv_sc *sc, unsigned long key,
               void *data, int data_length)
{
    switch (key) {
    case ETH_DRV_SET_MAC_ADDRESS:
        return 0;
        break;
    default:
        return 1;
        break;
    }
}

//
// This routine is called to see if it is possible to send another packet.
// It will return non-zero if a transmit is possible, zero otherwise.
//
static int
cs8900_can_send(struct eth_drv_sc *sc)
{
    struct cs8900_priv_data *cpd = (struct cs8900_priv_data *)sc->driver_private;
    unsigned short stat;
    stat = get_reg(PP_LineStat);
    if ((stat & PP_LineStat_LinkOK) == 0) {
        return false;  // Link not connected
    }
#ifdef CYGPKG_NET
    // Horrible hack!
    if (cpd->txbusy > 0) {
        cyg_tick_count_t now = cyg_current_time();
        if ((now - cpd->txstart) > 25) {
            // 250ms is more than enough to transmit one frame
            diag_printf("CS8900: Tx interrupt lost\n");
            cpd->txbusy = 0;
            // Free up the buffer (with error indication)
            (sc->funs->eth_drv->tx_done)(sc, cpd->txkey, 1);
        }
    }
#endif
    return (cpd->txbusy == 0);
}

//
// This routine is called to send data to the hardware.
static void 
cs8900_send(struct eth_drv_sc *sc, struct eth_drv_sg *sg_list, int sg_len, 
            int total_len, unsigned long key)
{
    struct cs8900_priv_data *cpd = (struct cs8900_priv_data *)sc->driver_private;
    int i;
    int len;
    unsigned char *data;
    unsigned short saved_data = 0, *sdata;
    unsigned short stat;
    bool odd_byte = false;

    // Mark xmitter busy
    cpd->txbusy = 1;
    cpd->txkey = key;
#ifdef CYGPKG_NET
    cpd->txstart = cyg_current_time();
#endif
    // Start the xmit sequence
// Note: this can go back once the 'dump' is removed
    CS8900_TxCMD = PP_TxCmd_TxStart_5;  // Start more-or-less immediately
//    CS8900_TxCMD = PP_TxCmd_TxStart_Full;  // Start only when all data sent to chip
    CS8900_TxLEN = total_len;
    stat = get_reg(PP_BusStat);  // This actually starts the xmit

    // Put data into buffer
    for (i = 0;  i < sg_len;  i++) {
        data = (unsigned char *)sg_list[i].buf;
        len = sg_list[i].len;
        if (len > 0) {
            /* Finish the last word. */
            if (odd_byte) {
                saved_data |= (*data++ << 8);
                CS8900_RTDATA = saved_data;
                len--;
                odd_byte = false;
            }
            /* Output contiguous words. */
            sdata = (unsigned short *)data;
            while (len > 1) {
                CS8900_RTDATA = *sdata++;
                len -= sizeof(unsigned short);
            }
            /* Save last byte, if necessary. */
            if (len == 1) {
                data = (unsigned char *)sdata;
                saved_data = *data;
                odd_byte = true;
            }
        }
    }
    if (odd_byte) {
        CS8900_RTDATA = saved_data;
    }
}

//
// This function is called when a packet has been received.  It's job is
// to prepare to unload the packet from the hardware.  Once the length of
// the packet is known, the upper layer of the driver can be told.  When
// the upper layer is ready to unload the packet, the internal function
// 'cs8900_recv' will be called to actually fetch it from the hardware.
//
static void
cs8900_RxEvent(struct eth_drv_sc *sc)
{
    unsigned short stat, len;

    stat = CS8900_RTDATA;
    len = CS8900_RTDATA;
    if (net_debug) {
        diag_printf("RxEvent - stat: %x, len: %d\n", stat, len);
    }
    (sc->funs->eth_drv->recv)(sc, len);
}

//
// This function is called as a result of the "eth_drv_recv()" call above.
// It's job is to actually fetch data for a packet from the hardware once
// memory buffers have been allocated for the packet.  Note that the buffers
// may come in pieces, using a scatter-gather list.  This allows for more
// efficient processing in the upper layers of the stack.
//
static void
cs8900_recv(struct eth_drv_sc *sc, struct eth_drv_sg *sg_list, int sg_len)
{
    int i, mlen;
    unsigned short *data, val;
    unsigned char *cp, cval;

    for (i = 0;  i < sg_len;  i++) {
        data = (unsigned short *)sg_list[i].buf;
        mlen = sg_list[i].len;
        while (mlen >= sizeof(*data)) {
            val = CS8900_RTDATA;
            if (data) {
                *data++ = val;
            }
            mlen -= sizeof(*data);
        }
        if (mlen) {
            // Fetch last odd byte
            cval = CS8900_RTDATA & 0xFF;
            if ((cp = (unsigned char *)data) != 0) {
                *cp = cval;
            }
        }
    }
}

static void
cs8900_TxEvent(struct eth_drv_sc *sc, int stat)
{
    struct cs8900_priv_data *cpd = (struct cs8900_priv_data *)sc->driver_private;
    stat = get_reg(PP_TER);
    if (net_debug) {
        diag_printf("Tx event: %x\n", stat);
    }
    cpd->txbusy = 0;
    (sc->funs->eth_drv->tx_done)(sc, cpd->txkey, 0);
}

static void
cs8900_BufEvent(struct eth_drv_sc *sc, int stat)
{
    if (stat & PP_BufCFG_RxMiss) {
    }
    if (stat & PP_BufCFG_TxUE) {
    }
}

static void
cs8900_int(struct eth_drv_sc *sc)
{
    unsigned short event;
    while ((event = CS8900_ISQ) != 0) {
        switch (event & ISQ_EventMask) {
        case ISQ_RxEvent:
            cs8900_RxEvent(sc);
            break;
        case ISQ_TxEvent:
            cs8900_TxEvent(sc, event);
            break;
        case ISQ_BufEvent:
            cs8900_BufEvent(sc, event);
            break;
        case ISQ_RxMissEvent:
            // Receive miss counter has overflowed
            break;
        case ISQ_TxColEvent:
            // Transmit collision counter has overflowed
            break;
        default:
            diag_printf("%s: Unknown event: %x\n", __FUNCTION__, event);
            break;
        }
    }
}

#ifdef INTS_DONT_WORK
void
cs8900_fake_int(cyg_addrword_t param)
{
    int s;
    while (true) {
        cyg_thread_delay(5);
        s = splnet();
        cs8900_int(&edb7xxx_sc);
        splx(s);
    }
}
#endif