ahdlcavr.c

含有完整TCP/IP PPP协议的嵌入式操作系统

/*
 * Copyright (C) 2003-2004 by egnite Software GmbH. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the copyright holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY EGNITE SOFTWARE GMBH AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EGNITE
 * SOFTWARE GMBH OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * For additional information see http://www.ethernut.de/
 *
 */

/*
 * $Log: ahdlcavr.c,v $
 * Revision 1.2  2005/08/02 17:46:45  haraldkipp
 * Major API documentation update.
 *
 * Revision 1.1  2005/07/26 18:02:27  haraldkipp
 * Moved from dev.
 *
 * Revision 1.10  2005/06/26 12:40:59  chaac
 * Added support for raw mode to AHDLC driver.
 *
 * Revision 1.9  2005/05/27 14:43:28  chaac
 * Fixed bugs on closing AHDLC sessions. Fixed AHDLC ioctl handling. Not all
 * messages were handled correctly	and fixed possible problem of reading memory
 * from address zero.
 *
 * Revision 1.8  2005/04/05 17:44:56  haraldkipp
 * Made stack space configurable.
 *
 * Revision 1.7  2005/02/10 07:06:17  hwmaier
 * Changes to incorporate support for AT90CAN128 CPU
 *
 * Revision 1.6  2005/01/24 21:11:48  freckle
 * renamed NutEventPostFromIRQ into NutEventPostFromIrq
 *
 * Revision 1.5  2005/01/21 16:49:45  freckle
 * Seperated calls to NutEventPostAsync between Threads and IRQs
 *
 * Revision 1.4  2004/12/16 08:40:35  haraldkipp
 * Late increment fixes ICCAVR bug.
 *
 * Revision 1.3  2004/03/18 14:05:20  haraldkipp
 * Comments updated
 *
 * Revision 1.2  2004/03/16 16:48:27  haraldkipp
 * Added Jan Dubiec's H8/300 port.
 *
 * Revision 1.1  2004/03/08 11:16:54  haraldkipp
 * Asynchronous HDLC driver added
 *
 */

#include <cfg/ahdlc.h>

#include <string.h>
#include <stdlib.h>

#include <sys/nutconfig.h>
#include <sys/atom.h>
#include <sys/heap.h>
#include <sys/event.h>
#include <sys/timer.h>
#include <sys/thread.h>

#include <dev/irqreg.h>
#include <dev/uartavr.h>

#include <fcntl.h>

#include <dev/ppp.h>
#include <dev/ahdlcavr.h>

#include <stdio.h>

/*!
 * \addtogroup xgAhdlcAvr
 */
/*@{*/

/*
 * FCS lookup table located in program memory space.
 */
static prog_char fcstab[512] = {
    0x00, 0x00, 0x11, 0x89, 0x23, 0x12, 0x32, 0x9b, 0x46, 0x24, 0x57, 0xad, 0x65, 0x36, 0x74, 0xbf,
    0x8c, 0x48, 0x9d, 0xc1, 0xaf, 0x5a, 0xbe, 0xd3, 0xca, 0x6c, 0xdb, 0xe5, 0xe9, 0x7e, 0xf8, 0xf7,
    0x10, 0x81, 0x01, 0x08, 0x33, 0x93, 0x22, 0x1a, 0x56, 0xa5, 0x47, 0x2c, 0x75, 0xb7, 0x64, 0x3e,
    0x9c, 0xc9, 0x8d, 0x40, 0xbf, 0xdb, 0xae, 0x52, 0xda, 0xed, 0xcb, 0x64, 0xf9, 0xff, 0xe8, 0x76,
    0x21, 0x02, 0x30, 0x8b, 0x02, 0x10, 0x13, 0x99, 0x67, 0x26, 0x76, 0xaf, 0x44, 0x34, 0x55, 0xbd,
    0xad, 0x4a, 0xbc, 0xc3, 0x8e, 0x58, 0x9f, 0xd1, 0xeb, 0x6e, 0xfa, 0xe7, 0xc8, 0x7c, 0xd9, 0xf5,
    0x31, 0x83, 0x20, 0x0a, 0x12, 0x91, 0x03, 0x18, 0x77, 0xa7, 0x66, 0x2e, 0x54, 0xb5, 0x45, 0x3c,
    0xbd, 0xcb, 0xac, 0x42, 0x9e, 0xd9, 0x8f, 0x50, 0xfb, 0xef, 0xea, 0x66, 0xd8, 0xfd, 0xc9, 0x74,

    0x42, 0x04, 0x53, 0x8d, 0x61, 0x16, 0x70, 0x9f, 0x04, 0x20, 0x15, 0xa9, 0x27, 0x32, 0x36, 0xbb,
    0xce, 0x4c, 0xdf, 0xc5, 0xed, 0x5e, 0xfc, 0xd7, 0x88, 0x68, 0x99, 0xe1, 0xab, 0x7a, 0xba, 0xf3,
    0x52, 0x85, 0x43, 0x0c, 0x71, 0x97, 0x60, 0x1e, 0x14, 0xa1, 0x05, 0x28, 0x37, 0xb3, 0x26, 0x3a,
    0xde, 0xcd, 0xcf, 0x44, 0xfd, 0xdf, 0xec, 0x56, 0x98, 0xe9, 0x89, 0x60, 0xbb, 0xfb, 0xaa, 0x72,
    0x63, 0x06, 0x72, 0x8f, 0x40, 0x14, 0x51, 0x9d, 0x25, 0x22, 0x34, 0xab, 0x06, 0x30, 0x17, 0xb9,
    0xef, 0x4e, 0xfe, 0xc7, 0xcc, 0x5c, 0xdd, 0xd5, 0xa9, 0x6a, 0xb8, 0xe3, 0x8a, 0x78, 0x9b, 0xf1,
    0x73, 0x87, 0x62, 0x0e, 0x50, 0x95, 0x41, 0x1c, 0x35, 0xa3, 0x24, 0x2a, 0x16, 0xb1, 0x07, 0x38,
    0xff, 0xcf, 0xee, 0x46, 0xdc, 0xdd, 0xcd, 0x54, 0xb9, 0xeb, 0xa8, 0x62, 0x9a, 0xf9, 0x8b, 0x70,

    0x84, 0x08, 0x95, 0x81, 0xa7, 0x1a, 0xb6, 0x93, 0xc2, 0x2c, 0xd3, 0xa5, 0xe1, 0x3e, 0xf0, 0xb7,
    0x08, 0x40, 0x19, 0xc9, 0x2b, 0x52, 0x3a, 0xdb, 0x4e, 0x64, 0x5f, 0xed, 0x6d, 0x76, 0x7c, 0xff,
    0x94, 0x89, 0x85, 0x00, 0xb7, 0x9b, 0xa6, 0x12, 0xd2, 0xad, 0xc3, 0x24, 0xf1, 0xbf, 0xe0, 0x36,
    0x18, 0xc1, 0x09, 0x48, 0x3b, 0xd3, 0x2a, 0x5a, 0x5e, 0xe5, 0x4f, 0x6c, 0x7d, 0xf7, 0x6c, 0x7e,
    0xa5, 0x0a, 0xb4, 0x83, 0x86, 0x18, 0x97, 0x91, 0xe3, 0x2e, 0xf2, 0xa7, 0xc0, 0x3c, 0xd1, 0xb5,
    0x29, 0x42, 0x38, 0xcb, 0x0a, 0x50, 0x1b, 0xd9, 0x6f, 0x66, 0x7e, 0xef, 0x4c, 0x74, 0x5d, 0xfd,
    0xb5, 0x8b, 0xa4, 0x02, 0x96, 0x99, 0x87, 0x10, 0xf3, 0xaf, 0xe2, 0x26, 0xd0, 0xbd, 0xc1, 0x34,
    0x39, 0xc3, 0x28, 0x4a, 0x1a, 0xd1, 0x0b, 0x58, 0x7f, 0xe7, 0x6e, 0x6e, 0x5c, 0xf5, 0x4d, 0x7c,

    0xc6, 0x0c, 0xd7, 0x85, 0xe5, 0x1e, 0xf4, 0x97, 0x80, 0x28, 0x91, 0xa1, 0xa3, 0x3a, 0xb2, 0xb3,
    0x4a, 0x44, 0x5b, 0xcd, 0x69, 0x56, 0x78, 0xdf, 0x0c, 0x60, 0x1d, 0xe9, 0x2f, 0x72, 0x3e, 0xfb,
    0xd6, 0x8d, 0xc7, 0x04, 0xf5, 0x9f, 0xe4, 0x16, 0x90, 0xa9, 0x81, 0x20, 0xb3, 0xbb, 0xa2, 0x32,
    0x5a, 0xc5, 0x4b, 0x4c, 0x79, 0xd7, 0x68, 0x5e, 0x1c, 0xe1, 0x0d, 0x68, 0x3f, 0xf3, 0x2e, 0x7a,
    0xe7, 0x0e, 0xf6, 0x87, 0xc4, 0x1c, 0xd5, 0x95, 0xa1, 0x2a, 0xb0, 0xa3, 0x82, 0x38, 0x93, 0xb1,
    0x6b, 0x46, 0x7a, 0xcf, 0x48, 0x54, 0x59, 0xdd, 0x2d, 0x62, 0x3c, 0xeb, 0x0e, 0x70, 0x1f, 0xf9,
    0xf7, 0x8f, 0xe6, 0x06, 0xd4, 0x9d, 0xc5, 0x14, 0xb1, 0xab, 0xa0, 0x22, 0x92, 0xb9, 0x83, 0x30,
    0x7b, 0xc7, 0x6a, 0x4e, 0x58, 0xd5, 0x49, 0x5c, 0x3d, 0xe3, 0x2c, 0x6a, 0x1e, 0xf1, 0x0f, 0x78
};

/*!
 * Checks the 32-bit ACCM to see if the byte needs un-escaping
 */
#define IN_ACC_MAP(c, m) (( ((u_char) (c)) < 0x20)  && ((m) & (1UL << (c))) != 0)

#ifndef NUT_THREAD_AHDLCRXSTACK
#define NUT_THREAD_AHDLCRXSTACK     512
#endif

/*
 * Handle AVR UART0 transmit complete interrupts.
 */
static void Tx0Complete(void *arg)
{
    AHDLCDCB *dcb = arg;

    if (dcb->dcb_tx_idx != dcb->dcb_wr_idx) {
#ifdef UART0_CTS_BIT
        if (bit_is_set(UART0_CTS_PIN, UART0_CTS_BIT)) {
            cbi(UCR, UDRIE);
            return;
        }
#endif
        outp(dcb->dcb_tx_buf[dcb->dcb_tx_idx], UDR);
        dcb->dcb_tx_idx++;
    } else {
        cbi(UCR, UDRIE);
        NutEventPostFromIrq(&dcb->dcb_tx_rdy);
    }
}

#ifdef UART0_CTS_BIT
/*
 * Handle AVR UART0 transmit handshake interrupts.
 */
static void Cts0Interrupt(void *arg)
{
    sbi(UCR, UDRIE);
}
#endif

#ifdef __AVR_ENHANCED__
/*
 * Handle AVR UART1 transmit complete interrupts.
 */
static void Tx1Complete(void *arg)
{
    register AHDLCDCB *dcb = arg;

    if (dcb->dcb_tx_idx != dcb->dcb_wr_idx) {
#ifdef UART1_CTS_BIT
        if (bit_is_set(UART1_CTS_PIN, UART1_CTS_BIT)) {
            cbi(UCSR1B, UDRIE);
            return;
        }
#endif
        outp(dcb->dcb_tx_buf[dcb->dcb_tx_idx], UDR1);
        dcb->dcb_tx_idx++;
    } else {
        cbi(UCSR1B, UDRIE);
        NutEventPostFromIrq(&dcb->dcb_tx_rdy);
    }
}

#ifdef UART1_CTS_BIT
/*
 * Handle AVR UART1 transmit handshake interrupts.
 */
static void Cts1Interrupt(void *arg)
{
    sbi(UCSR1B, UDRIE);
}
#endif

#endif                          /* __AVR_ENHANCED__ */

/*
 * Handle AVR UART0 receive complete interrupts.
 */
static void Rx0Complete(void *arg)
{
    AHDLCDCB *dcb = arg;

    dcb->dcb_rx_buf[dcb->dcb_rx_idx] = inp(UDR);
    if (dcb->dcb_rd_idx == dcb->dcb_rx_idx)
        NutEventPostFromIrq(&dcb->dcb_rx_rdy);
    /* Late increment fixes ICCAVR bug on volatile variables. */
    dcb->dcb_rx_idx++;
}

#ifdef __AVR_ENHANCED__
/*
 * Handle AVR UART1 receive complete interrupts.
 */
static void Rx1Complete(void *arg)
{
    AHDLCDCB *dcb = arg;

    dcb->dcb_rx_buf[dcb->dcb_rx_idx] = inp(UDR1);
    if (dcb->dcb_rd_idx == dcb->dcb_rx_idx)
        NutEventPostFromIrq(&dcb->dcb_rx_rdy);
    /* Late increment fixes ICCAVR bug on volatile variables. */
    dcb->dcb_rx_idx++;
}
#endif                          /* __AVR_ENHANCED__ */

/*
 * \return 0 on success, -1 in case of any errors.
 */
static int SendRawByte(AHDLCDCB * dcb, u_char ch, u_char flush)
{
    /*
     * If transmit buffer is full, wait until interrupt routine
     * signals an empty buffer or until a timeout occurs.
     */
    while ((u_char) (dcb->dcb_wr_idx + 1) == dcb->dcb_tx_idx) {
        if (NutEventWait(&dcb->dcb_tx_rdy, dcb->dcb_wtimeout))
            break;
    }

    /*
     * If transmit buffer is still full, we have a write timeout.
     */
    if ((u_char) (dcb->dcb_wr_idx + 1) == dcb->dcb_tx_idx) {
        return -1;
    }

    /*
     * Buffer has room for more data. Put the byte in the buffer
     * and increment the write index.
     */
    dcb->dcb_tx_buf[dcb->dcb_wr_idx] = ch;
    dcb->dcb_wr_idx++;

    /*
     * If transmit buffer has become full and the transmitter
     * is not active, then activate it.
     */
    if (flush || (u_char) (dcb->dcb_wr_idx + 1) == dcb->dcb_tx_idx) {

        /*
         * TODO: Check handshake.
         */
        NutEnterCritical();
#ifdef __AVR_ENHANCED__
        if (dcb->dcb_base)
            sbi(UCSR1B, UDRIE);
        else
#endif
            sbi(UCR, UDRIE);
        NutExitCritical();
    }
    return 0;
}

/*
 * Characters are properly escaped and checksum is updated.
 *
 * \return 0 on success, -1 in case of any errors.
 */
static int SendHdlcData(AHDLCDCB * dcb, CONST u_char * data, u_short len, u_short * txfcs)
{
    u_short tbx;
    register u_short fcs;

    if (txfcs)
        fcs = *txfcs;
    else
        fcs = 0;
    while (len) {
        tbx = (u_short) ((u_char) fcs ^ *data) << 1;
        fcs >>= 8;
        fcs ^= ((u_short) PRG_RDB(fcstab + tbx) << 8) | PRG_RDB(fcstab + tbx + 1);
        if (IN_ACC_MAP(*data, dcb->dcb_tx_accm) || *data == AHDLC_FLAG || *data == AHDLC_ESCAPE) {
            if (SendRawByte(dcb, AHDLC_ESCAPE, 0))
                return -1;
            if (SendRawByte(dcb, *data ^ AHDLC_TRANS, 0))
                return -1;
        } else if (SendRawByte(dcb, *data, 0))
            return -1;
        data++;
        len--;
    }
    if (txfcs)
        *txfcs = fcs;

    return 0;
}

/*!
 * \brief Send HDLC frame.
 *
 * \param dev   Identifies the device to use.
 * \param nb    Network buffer structure containing the packet to be sent.
 *              The structure must have been allocated by a previous
 *              call NutNetBufAlloc().
 *
 * \return 0 on success, -1 in case of any errors.
 */
int AhdlcOutput(NUTDEVICE * dev, NETBUF * nb)
{
    u_short txfcs;
    AHDLCDCB *dcb = dev->dev_dcb;
    u_short sz;

    /*
     * If we are in RAW mode we are not allowed to send AHDLC output.
     * We just emulate packet loss behaviour in here.
     */
    if (dcb->dcb_modeflags & UART_MF_RAWMODE) {
        return 0;
    }

    /*
     * Calculate the number of bytes to be send. Do not
     * send packets larger than transmit mru.
     */
    sz = nb->nb_dl.sz + nb->nb_nw.sz + nb->nb_tp.sz + nb->nb_ap.sz;

    if (sz > dcb->dcb_tx_mru) {
        return -1;
    }

    /*
     * TODO: If transmitter is running, we may omit the flag.
     */
    SendRawByte(dcb, AHDLC_FLAG, 0);

    /* Initialize the checksum and send the NETBUF. */
    txfcs = AHDLC_INITFCS;
    if (SendHdlcData(dcb, nb->nb_dl.vp, nb->nb_dl.sz, &txfcs))
        return -1;
    if (SendHdlcData(dcb, nb->nb_nw.vp, nb->nb_nw.sz, &txfcs))
        return -1;
    if (SendHdlcData(dcb, nb->nb_tp.vp, nb->nb_tp.sz, &txfcs))
        return -1;
    if (SendHdlcData(dcb, nb->nb_ap.vp, nb->nb_ap.sz, &txfcs))
        return -1;

    /* Send the checksum and the final flag. */
    txfcs ^= 0xffff;
    if (SendHdlcData(dcb, (u_char *) & txfcs, 2, 0))
        return -1;
    SendRawByte(dcb, AHDLC_FLAG, 1);

    return 0;
}

/*! \fn AhdlcRx(void *arg)
 * \brief Asynchronous HDLC receiver thread.
 *
 *
 * Running at high priority.
 */
THREAD(AhdlcRx, arg)
{
    NUTDEVICE *dev = arg;
    NUTDEVICE *netdev;
    AHDLCDCB *dcb = dev->dev_dcb;
    IFNET *ifn;
    NETBUF *nb;
    u_char *rxbuf;
    u_char *rxptr;
    u_short rxcnt;
    u_char ch;
    u_short tbx;
    u_char inframe;
    u_char escaped;
    u_short rxfcs;

    NutThreadSetPriority(9);
    for (;;) {
        /*
         * Reset variables to their initial state
         */
        rxptr = 0;
        rxcnt = 0;
        escaped = 0;
        rxfcs = AHDLC_INITFCS;
        inframe = 0;

        for (;;) {
            /*
             * Wait until the network interface has been attached.
             * This will be initiated by the application calling
             * NutNetIfConfig(), which in turn calls a HDLC_SETIFNET
             * ioctl() to store the NUTDEVICE pointer of the network
             * device in dev_icb and trigger an event on dcb_mf_evt.
             */
            while ((netdev = dev->dev_icb) == 0) {
                NutEventWait(&dcb->dcb_mf_evt, 1000);
            }
            ifn = netdev->dev_icb;
            dcb->dcb_rtimeout = 1000;
            inframe = 0;

            /*
             * Allocate the receive buffer, if this fails, we are in a
             * low memory situation. Take a nap and see, if the
             * situation improved.
             */
            if ((rxbuf = NutHeapAlloc(dcb->dcb_rx_mru)) != 0) {
                break;
            }
            NutSleep(1000);
        }

        /*
         * Signal the link driver that we are up.
         */
        ifn->if_send = AhdlcOutput;
        netdev->dev_ioctl(netdev, LCP_LOWERUP, 0);

        for (;;) {
            /*