eth_drv.c

eCos操作系统源码

//==========================================================================
//
//      src/stand_alone/eth_drv.c
//
//      Stand-alone hardware independent networking support for RedBoot
//
//==========================================================================
//####ECOSGPLCOPYRIGHTBEGIN####
// -------------------------------------------
// This file is part of eCos, the Embedded Configurable Operating System.
// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003 Red Hat, Inc.
// Copyright (C) 2003 Gary Thomas
//
// eCos is free software; you can redistribute it and/or modify it under
// the terms of the GNU General Public License as published by the Free
// Software Foundation; either version 2 or (at your option) any later version.
//
// eCos is distributed in the hope that it will be useful, but WITHOUT ANY
// WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
// for more details.
//
// You should have received a copy of the GNU General Public License along
// with eCos; if not, write to the Free Software Foundation, Inc.,
// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
//
// As a special exception, if other files instantiate templates or use macros
// or inline functions from this file, or you compile this file and link it
// with other works to produce a work based on this file, this file does not
// by itself cause the resulting work to be covered by the GNU General Public
// License. However the source code for this file must still be made available
// in accordance with section (3) of the GNU General Public License.
//
// This exception does not invalidate any other reasons why a work based on
// this file might be covered by the GNU General Public License.
//
// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.
// at http://sources.redhat.com/ecos/ecos-license/
// -------------------------------------------
//####ECOSGPLCOPYRIGHTEND####
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    gthomas
// Contributors: gthomas
// Date:         2000-07-14
// Purpose:      
// Description:  
//              
// This code is part of RedBoot (tm).
//
//####DESCRIPTIONEND####
//
//==========================================================================

#include <pkgconf/system.h>
#include <pkgconf/io_eth_drivers.h>

#include <cyg/infra/cyg_type.h>
#include <cyg/hal/hal_arch.h>
#include <cyg/infra/diag.h>
#include <cyg/hal/drv_api.h>
#include <cyg/hal/hal_if.h>
#include <cyg/io/eth/eth_drv.h>
#include <cyg/io/eth/netdev.h>
#include <string.h>

// High-level ethernet driver


// Interfaces exported to drivers

static void eth_drv_init(struct eth_drv_sc *sc, unsigned char *enaddr);
static void eth_drv_recv(struct eth_drv_sc *sc, int total_len);
static void eth_drv_tx_done(struct eth_drv_sc *sc, CYG_ADDRWORD key, int status);

struct eth_drv_funs eth_drv_funs = {eth_drv_init, eth_drv_recv, eth_drv_tx_done};

#ifdef CYGDBG_IO_ETH_DRIVERS_DEBUG
int cyg_io_eth_net_debug = CYGDBG_IO_ETH_DRIVERS_DEBUG_VERBOSITY;
// Usually just the header is enough, the body slows things too much.
#define DIAG_DUMP_BUF_HDR( a, b ) if (0 < cyg_io_eth_net_debug) diag_dump_buf( (a), (b) )
#define DIAG_DUMP_BUF_BDY( a, b ) if (1 < cyg_io_eth_net_debug) diag_dump_buf( (a), (b) )
#else
#define DIAG_DUMP_BUF_HDR( a, b )
#define DIAG_DUMP_BUF_BDY( a, b )
#endif

struct eth_drv_sc *__local_enet_sc = NULL;

#ifdef CYGSEM_IO_ETH_DRIVERS_PASS_PACKETS
//
// Horrible hack: In order to allow the stand-alone networking code to work
// alongside eCos (or any other stack), separate IP addresses must be used.
// When a packet arrives at the interface, we check to see which IP address
// it corresponds to and only pass it "up" if it's not for the stand-alone
// layer.
//
// tres degolas :-(
//
extern char __local_ip_addr[4]; 
#endif // PASS_PACKETS

#ifdef CYGDBG_HAL_DEBUG_GDB_THREAD_SUPPORT
//
// Another horrible hack: In order to do the above passing on of
// application packets safely - and passing on completion events for
// pending transmissions (which is not conditional) - we must lock the
// application scheduler before calling into it.  There are several reasons
// for this: a) We are likely running on a RedBoot special debug stack and
// so the application's stack checking fires; b) we could even get
// descheduled if the arrival of a packet causes a higher priority thread
// to awaken!

#include <cyg/hal/dbg-threads-api.h>

// Use with care!  Local variable defined!
# define    LOCK_APPLICATION_SCHEDULER()                                \
{   /* NEW BLOCK */                                                     \
    threadref currthread;                                               \
    int threadok;                                                       \
    threadok = dbg_currthread( &currthread );                           \
    if ( threadok ) {                                                   \
        threadok = dbg_scheduler( &currthread, 1, 1 ); /* lock */       \
    }

# define  UNLOCK_APPLICATION_SCHEDULER()                        	\
    if ( threadok ) {                                           	\
        dbg_scheduler( &currthread, 0, 1 ); /* unlock */        	\
    }                                                           	\
}   /* END BLOCK */

#else
# define    LOCK_APPLICATION_SCHEDULER() CYG_EMPTY_STATEMENT
# define  UNLOCK_APPLICATION_SCHEDULER() CYG_EMPTY_STATEMENT
#endif // GDB_THREAD_SUPPORT

//
// Buffer 'get' support.  The problem is that this function only gets
// called when some data is required, but packets may arrive on the device
// at any time.  More particularly, on some devices when data arrive, all
// of that data needs to be consumed immediately or be lost.  This process
// is driven by interrupts, which in the stand-along case are simulated by
// calling the "poll" interface.
//
// Thus there will be a pool of buffers, some free and some full, to try
// and manage this.
//

#define MAX_ETH_MSG 1540
#define NUM_ETH_MSG CYGNUM_IO_ETH_DRIVERS_NUM_PKT

struct eth_msg {
    struct eth_msg *next, *prev;
    int len;   // Actual number of bytes in message
    unsigned char data[MAX_ETH_MSG];
};

struct eth_msg_hdr {
    struct eth_msg *first, *last;
};

static struct eth_msg_hdr eth_msg_free, eth_msg_full;
static struct eth_msg eth_msgs[NUM_ETH_MSG];

// Prototypes for functions used in this module
static void eth_drv_start(struct eth_drv_sc *sc);

// These functions are defined in RedBoot and control access to
// the "default" console.
extern int  start_console(void);
extern void end_console(int);

// Simple queue management functions

static void
eth_drv_msg_put(struct eth_msg_hdr *hdr, struct eth_msg *msg)
{
    if (hdr->first != (struct eth_msg *)hdr) {
        // Something already in queue
        hdr->last->next = msg;
        msg->prev = hdr->last;
        msg->next = (struct eth_msg *)hdr;
        hdr->last = msg;
    } else {
        hdr->first = hdr->last = msg;
        msg->next = msg->prev = (struct eth_msg *)hdr;
    }
}

static struct eth_msg *
eth_drv_msg_get(struct eth_msg_hdr *hdr)
{
    struct eth_msg *msg;
    if (hdr->first != (struct eth_msg *)hdr) {
        msg = hdr->first;
        hdr->first = msg->next;
        msg->next->prev = (struct eth_msg *)hdr;
    } else {
        msg = (struct eth_msg *)NULL;
    }
    return msg;
}

void
eth_drv_buffers_init(void)
{
    int i;
    struct eth_msg *msg = eth_msgs;

    eth_msg_full.first = eth_msg_full.last = (struct eth_msg *)&eth_msg_full;
    eth_msg_free.first = eth_msg_free.last = (struct eth_msg *)&eth_msg_free;
    for (i = 0;  i < NUM_ETH_MSG;  i++, msg++) {
        eth_drv_msg_put(&eth_msg_free, msg);
    }
}

//
// This function is called during system initialization to register a
// network interface with the system.
//
static void
eth_drv_init(struct eth_drv_sc *sc, unsigned char *enaddr)
{
    // enaddr == 0 -> hardware init was incomplete (no ESA)
    if (enaddr != 0) {
        // Set up hardware address
        memcpy(&sc->sc_arpcom.esa, enaddr, ETHER_ADDR_LEN);
        __local_enet_sc = sc;
        eth_drv_start(sc);
    }
}

//
// This [internal] function will be called to stop activity on an interface.
//
void
eth_drv_stop(void)
{
    struct eth_drv_sc *sc = __local_enet_sc;

    if (sc != NULL)
        (sc->funs->stop)(sc);
}

//
// This [internal] function will be called to start activity on an interface.
//
static void
eth_drv_start(struct eth_drv_sc *sc)
{
    // Perform any hardware initialization
    (sc->funs->start)(sc, (unsigned char *)&sc->sc_arpcom.esa, 0);
}

//
// Send a packet of data to the hardware
//
static int packet_sent;

void
eth_drv_write(char *eth_hdr, char *buf, int len)
{
    struct eth_drv_sg sg_list[MAX_ETH_DRV_SG];
    struct eth_drv_sc *sc = __local_enet_sc;
    int sg_len = 2;
    void *dbg = CYGACC_CALL_IF_DBG_DATA();
    int old_state;
    int wait_time = 5;  // Timeout before giving up
    void *eth_drv_old = 0;

    if (dbg) {
        sc = (struct eth_drv_sc *)dbg;  // Use control from installed driver
        eth_drv_old = sc->funs->eth_drv_old;
        if (eth_drv_old == 0) {
            sc->funs->eth_drv_old = sc->funs->eth_drv;        
            sc->funs->eth_drv = &eth_drv_funs;    // Substitute stand-alone driver
            old_state = sc->state;
            if (!old_state & ETH_DRV_STATE_ACTIVE) {