if_enp.c

早期freebsd实现

/*
 * Copyright (c) 1988 Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Computer Consoles Inc.
 *
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 THE REGENTS 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.
 *
 *	@(#)if_enp.c	7.8 (Berkeley) 12/16/90
 */

#include "enp.h"
#if NENP > 0
/*
 * CMC ENP-20 Ethernet Controller.
 */
#include "sys/param.h"
#include "sys/systm.h"
#include "sys/mbuf.h"
#include "sys/buf.h"
#include "sys/protosw.h"
#include "sys/socket.h"
#include "sys/vmmac.h"
#include "sys/ioctl.h"
#include "sys/errno.h"
#include "sys/vmparam.h"
#include "sys/syslog.h"
#include "sys/uio.h"

#include "net/if.h"
#include "net/netisr.h"
#include "net/route.h"
#ifdef INET
#include "netinet/in.h"
#include "netinet/in_systm.h"
#include "netinet/in_var.h"
#include "netinet/ip.h"
#include "netinet/ip_var.h"
#include "netinet/if_ether.h"
#endif
#ifdef NS
#include "netns/ns.h"
#include "netns/ns_if.h"
#endif

#include "../include/cpu.h"
#include "../include/pte.h"
#include "../include/mtpr.h"

#include "../vba/vbavar.h"
#include "../if/if_enpreg.h"

#define ENPSTART	0xf02000	/* standard enp start addr */
#define	ENPUNIT(dev)	(minor(dev))	/* for enp ram devices */
/* macros for dealing with longs in i/o space */
#define	ENPGETLONG(a)	((((u_short *)(a))[0] << 16)|(((u_short *)(a))[1]))
#define	ENPSETLONG(a,v) \
   { register u_short *wp = (u_short *)(a); \
     wp[0] = ((u_short *)&(v))[0]; wp[1] = ((u_short *)&(v))[1];}

int	enpprobe(), enpattach(), enpintr();
long	enpstd[] = { 0xfff41000, 0xfff61000, 0 };
struct  vba_device *enpinfo[NENP];
struct  vba_driver enpdriver = 
    { enpprobe, 0, enpattach, 0, enpstd, "enp", enpinfo, "enp-20", 0 };

int	enpinit(), enpioctl(), enpreset(), enpoutput(), enpstart();
struct  mbuf *enpget();

/*
 * Ethernet software status per interface.
 *
 * Each interface is referenced by a network interface structure,
 * es_if, which the routing code uses to locate the interface.
 * This structure contains the output queue for the interface, its address, ...
 */
struct  enp_softc {
	struct  arpcom es_ac;           /* common ethernet structures */
#define es_if		es_ac.ac_if
#define es_addr	es_ac.ac_enaddr
	short	es_ivec;		/* interrupt vector */
} enp_softc[NENP]; 
extern	struct ifnet loif;

enpprobe(reg, vi)
	caddr_t reg;
	struct vba_device *vi;
{
	register br, cvec;		/* must be r12, r11 */
	register struct enpdevice *addr = (struct enpdevice *)reg;
	struct enp_softc *es = &enp_softc[vi->ui_unit];

#ifdef lint
	br = 0; cvec = br; br = cvec;
	enpintr(0);
#endif
	if (badaddr((caddr_t)addr, 2) || badaddr((caddr_t)&addr->enp_ram[0], 2))
		return (0);
	es->es_ivec = --vi->ui_hd->vh_lastiv;
	addr->enp_state = S_ENPRESET;		/* reset by VERSAbus reset */
	br = 0x14, cvec = es->es_ivec;		/* XXX */
	return (sizeof (struct enpdevice));
}

/*
 * Interface exists: make available by filling in network interface
 * record.  System will initialize the interface when it is ready
 * to accept packets. 
 */
enpattach(ui)
	register struct vba_device *ui;
{
	struct enp_softc *es = &enp_softc[ui->ui_unit];
	register struct ifnet *ifp = &es->es_if;

	ifp->if_unit = ui->ui_unit;
	ifp->if_name = "enp";
	ifp->if_mtu = ETHERMTU;
	ifp->if_init = enpinit;
	ifp->if_ioctl = enpioctl;
	ifp->if_output = ether_output;
	ifp->if_start = enpstart;
	ifp->if_reset = enpreset;
	ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX;
	if_attach(ifp);
}

/*
 * Reset of interface after "system" reset.
 */
enpreset(unit, vban)
	int unit, vban;
{
	register struct vba_device *ui;

	if (unit >= NENP || (ui = enpinfo[unit]) == 0 || ui->ui_alive == 0 ||
	    ui->ui_vbanum != vban)
		return;
	printf(" enp%d", unit);
	enpinit(unit);
}

/*
 * Initialization of interface; clear recorded pending operations.
 */
enpinit(unit)
	int unit;
{
	struct enp_softc *es = &enp_softc[unit];
	register struct vba_device *ui = enpinfo[unit];
	struct enpdevice *addr;
	register struct ifnet *ifp = &es->es_if;
	int s;

	if (ifp->if_addrlist == (struct ifaddr *)0)
		return;
	if ((ifp->if_flags & IFF_RUNNING) == 0) {
		addr = (struct enpdevice *)ui->ui_addr;
		s = splimp();
		RESET_ENP(addr);
		DELAY(200000);
		es->es_if.if_flags |= IFF_RUNNING;
		splx(s);
	}
}

/*
 * Ethernet interface interrupt.
 */
enpintr(unit)
	int unit;
{
	register struct enpdevice *addr;
	register BCB *bcbp;

	addr = (struct enpdevice *)enpinfo[unit]->ui_addr;
#if ENP == 30
	if (!IS_ENP_INTR(addr))
		return;
	ACK_ENP_INTR(addr);
#endif
	while ((bcbp = (BCB *)ringget((RING *)&addr->enp_tohost )) != 0) {
		enpread(&enp_softc[unit], bcbp);
		(void) ringput((RING *)&addr->enp_enpfree, bcbp); 
	}
}

/*
 * Read input packet, examine its packet type, and enqueue it.
 */
enpread(es, bcbp)
	struct enp_softc *es;
	register BCB *bcbp;
{
	register struct ether_header *enp;
	struct mbuf *m;
	int s, len, off, resid;

	es->es_if.if_ipackets++; 
	/*
	 * Get input data length.
	 * Get pointer to ethernet header (in input buffer).
	 * Deal with trailer protocol: if type is PUP trailer
	 * get true type from first 16-bit word past data.
	 * Remember that type was trailer by setting off.
	 */
	len = bcbp->b_msglen - sizeof (struct ether_header);
	enp = (struct ether_header *)ENPGETLONG(&bcbp->b_addr);
#define enpdataaddr(enp, off, type) \
    ((type)(((caddr_t)(((char *)enp)+sizeof (struct ether_header))+(off))))
	enp->ether_type = ntohs((u_short)enp->ether_type);
	if (enp->ether_type >= ETHERTYPE_TRAIL &&
	    enp->ether_type < ETHERTYPE_TRAIL+ETHERTYPE_NTRAILER) {
		off = (enp->ether_type - ETHERTYPE_TRAIL) * 512;
		if (off >= ETHERMTU)
			return;
		enp->ether_type = ntohs(*enpdataaddr(enp, off, u_short *));
		resid = ntohs(*(enpdataaddr(enp, off+2, u_short *)));
		if (off + resid > len)
			return;
		len = off + resid;
	} else
		off = 0;
	if (len == 0)
		return;

	/*
	 * Pull packet off interface.  Off is nonzero if packet
	 * has trailing header; enpget will then force this header
	 * information to be at the front.
	 */
	m = enpget((u_char *)enp, len, off, &es->es_if);
	if (m == 0)
		return;
	ether_input(&es->es_if, enp, m);
}

enpstart(ifp)
	struct ifnet *ifp;
{

	if (enpput(ifp))
		return (ENOBUFS);
	else
		return (0);
}

/*
 * Routine to copy from mbuf chain to transmitter buffer on the VERSAbus.
 */
enpput(ifp)
struct ifnet *ifp;
{
	register BCB *bcbp;
	register struct enpdevice *addr;
	register struct mbuf *mp;
	register u_char *bp;
	register u_int len;
	int unit = ifp->if_unit, ret = 1;
	struct mbuf *m;

	addr = (struct enpdevice *)enpinfo[unit]->ui_addr;
again:
	if (ringempty((RING *)&addr->enp_hostfree))  {
	/*	ifp->if_flags |= IFF_OACTIVE; */
		return (ret);
	}
	IF_DEQUEUE(&ifp->if_snd, m);
	if (m == 0) {
		ifp->if_flags &= ~IFF_OACTIVE;
		return (0);
	}
	bcbp = (BCB *)ringget((RING *)&addr->enp_hostfree);
	bcbp->b_len = 0;
	bp = (u_char *)ENPGETLONG(&bcbp->b_addr);
	for (mp = m; mp; mp = mp->m_next) {
		len = mp->m_len;
		if (len == 0)
			continue;
		enpcopy(mtod(mp, u_char *), bp, len);
		bp += len;
		bcbp->b_len += len;
	}
	bcbp->b_len = max(ETHERMIN+sizeof (struct ether_header), bcbp->b_len);
	bcbp->b_reserved = 0;
	if (ringput((RING *)&addr->enp_toenp, bcbp) == 1)
		INTR_ENP(addr);
	m_freem(m);
	ret = 0;
	goto again;
}

/*
 * Routine to copy from VERSAbus memory into mbufs.
 *
 * Warning: This makes the fairly safe assumption that
 * mbufs have even lengths.
 */
struct mbuf *
enpget(rxbuf, totlen, off, ifp)
	u_char *rxbuf;
	int totlen, off;
	struct ifnet *ifp;
{
	register u_char *cp;
	register struct mbuf *m;
	struct mbuf *top = 0, **mp = &top;
	int len;
	u_char *packet_end;

	rxbuf += sizeof (struct ether_header);
	cp = rxbuf;
	packet_end = cp + totlen;
	if (off) {
		off += 2 * sizeof(u_short);
		totlen -= 2 *sizeof(u_short);
		cp = rxbuf + off;