NetBSD-5.0.2/sys/arch/acorn26/ioc/if_eca.c
/* $NetBSD: if_eca.c,v 1.8 2007/10/17 19:52:52 garbled Exp $ */
/*-
* Copyright (c) 2001 Ben Harris
* 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#include <sys/param.h>
__KERNEL_RCSID(0, "$NetBSD: if_eca.c,v 1.8 2007/10/17 19:52:52 garbled Exp $");
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/socket.h>
#include <sys/syslog.h>
#include <sys/systm.h>
#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_eco.h>
#include <machine/bus.h>
#include <machine/fiq.h>
#include <machine/intr.h>
#include <machine/machdep.h>
#include <arch/acorn26/iobus/iocvar.h>
#include <dev/ic/mc6854reg.h>
#include <arch/acorn26/ioc/if_ecavar.h>
static int eca_match(struct device *, struct cfdata *, void *);
static void eca_attach(struct device *, struct device *, void *);
static int eca_init(struct ifnet *);
static void eca_stop(struct ifnet *ifp, int disable);
static int eca_claimwire(struct ifnet *);
static void eca_txframe(struct ifnet *, struct mbuf *);
static void eca_tx_downgrade(void);
static void eca_txdone(void *);
static int eca_init_rxbuf(struct eca_softc *sc, int flags);
static void eca_init_rx_soft(struct eca_softc *sc);
static void eca_init_rx_hard(struct eca_softc *sc);
static void eca_init_rx(struct eca_softc *sc);
static void eca_rx_downgrade(void);
static void eca_gotframe(void *);
struct eca_softc *eca_fiqowner;
CFATTACH_DECL(eca, sizeof(struct eca_softc),
eca_match, eca_attach, NULL, NULL);
static int
eca_match(struct device *parent, struct cfdata *cf, void *aux)
{
struct ioc_attach_args *ioc = aux;
/* Econet never uses LOOP mode. */
if ((bus_space_read_1(ioc->ioc_sync_t, ioc->ioc_sync_h, MC6854_SR1) &
MC6854_SR1_LOOP) != 0)
return 0;
return 1;
}
static void
eca_attach(struct device *parent, struct device *self, void *aux)
{
struct eca_softc *sc = (void *)self;
struct ioc_attach_args *ioc = aux;
struct ifnet *ifp = &sc->sc_ec.ec_if;
u_int8_t myaddr[ECO_ADDR_LEN];
sc->sc_iot = ioc->ioc_sync_t;
sc->sc_ioh = ioc->ioc_sync_h;
myaddr[0] = cmos_read(0x40);
myaddr[1] = 0;
printf(": station %s", eco_sprintf(myaddr));
/* It's traditional to print the clock state at boot. */
if ((bus_space_read_1(sc->sc_iot, sc->sc_ioh, MC6854_SR2) &
MC6854_SR2_NDCD))
printf(", no clock");
/* Initialise ifnet structure. */
strcpy(ifp->if_xname, sc->sc_dev.dv_xname);
ifp->if_softc = sc;
ifp->if_init = eca_init;
ifp->if_stop = eca_stop;
ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_NOTRAILERS;
IFQ_SET_READY(&ifp->if_snd);
sc->sc_ec.ec_claimwire = eca_claimwire;
sc->sc_ec.ec_txframe = eca_txframe;
sc->sc_rx_soft = softintr_establish(IPL_SOFTNET, eca_gotframe, sc);
sc->sc_tx_soft = softintr_establish(IPL_SOFTNET, eca_txdone, sc);
if (sc->sc_rx_soft == NULL || sc->sc_tx_soft == NULL) {
printf("\n%s: failed to establish software interrupt\n",
sc->sc_dev.dv_xname);
return;
}
if_attach(ifp);
eco_ifattach(ifp, myaddr);
sc->sc_fiqhandler.fh_func = eca_fiqhandler;
sc->sc_fiqhandler.fh_size = eca_efiqhandler - eca_fiqhandler;
sc->sc_fiqhandler.fh_flags = 0;
sc->sc_fiqhandler.fh_regs = &sc->sc_fiqstate.efs_rx_fiqregs;
printf("\n");
}
static int
eca_init(struct ifnet *ifp)
{
struct eca_softc *sc = ifp->if_softc;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
int sr1, sr2;
int err;
if ((err = eco_init(ifp)) != 0)
return err;
/* Claim the FIQ early, in case we don't get it. */
if ((err = fiq_claim(&sc->sc_fiqhandler)) != 0)
return err;
if (sc->sc_rcvmbuf == NULL) {
err = eca_init_rxbuf(sc, M_WAIT);
if (err != 0)
return err;
}
sc->sc_transmitting = 0;
/* Interrupts disabled, no DMA, hold Tx and Rx in reset. */
sc->sc_cr1 = MC6854_CR1_RX_RS | MC6854_CR1_TX_RS;
/* 1-byte transfers, mark idle. */
sc->sc_cr2 = 0;
/* Nothing exciting. */
sc->sc_cr3 = 0;
/* single flag, 8 data bits, NRZ */
sc->sc_cr4 = MC6854_CR4_TX_WL_8BITS | MC6854_CR4_RX_WL_8BITS;
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1);
bus_space_write_1(iot, ioh, MC6854_CR2, sc->sc_cr2);
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1 | MC6854_CR1_AC);
bus_space_write_1(iot, ioh, MC6854_CR3, sc->sc_cr3);
bus_space_write_1(iot, ioh, MC6854_CR4, sc->sc_cr4);
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1);
/* Everything's set up. Take chip out of reset. */
sc->sc_cr1 &= ~(MC6854_CR1_RX_RS | MC6854_CR1_TX_RS);
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1);
/* Read and clear status registers. */
sr1 = bus_space_read_1(iot, ioh, MC6854_SR1);
sr2 = bus_space_read_1(iot, ioh, MC6854_SR2);
bus_space_write_1(iot, ioh, MC6854_CR2, sc->sc_cr2 |
MC6854_CR2_CLR_RX_ST | MC6854_CR2_CLR_TX_ST);
/* Set up FIQ registers and enable FIQs */
eca_init_rx(sc);
ifp->if_flags |= IFF_RUNNING;
return 0;
}
/*
* Check if the network's idle, and if it is, start flag-filling.
*/
static int
eca_claimwire(struct ifnet *ifp)
{
struct eca_softc *sc = ifp->if_softc;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
KASSERT(sc->sc_ec.ec_state == ECO_IDLE);
if (bus_space_read_1(iot, ioh, MC6854_SR2) & MC6854_SR2_RX_IDLE) {
/* Start flag fill. */
sc->sc_cr2 |= MC6854_CR2_RTS | MC6854_CR2_F_M_IDLE;
bus_space_write_1(iot, ioh, MC6854_CR2, sc->sc_cr2);
return 0;
}
return EBUSY;
}
static void
eca_txframe(struct ifnet *ifp, struct mbuf *m)
{
struct eca_softc *sc = ifp->if_softc;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
struct fiqregs fr;
ioc_fiq_setmask(0);
/* Start flag-filling while we work out what to do next. */
sc->sc_cr2 |= MC6854_CR2_RTS | MC6854_CR2_F_M_IDLE;
bus_space_write_1(iot, ioh, MC6854_CR2, sc->sc_cr2);
sc->sc_fiqstate.efs_fiqhandler = eca_fiqhandler_tx;
sc->sc_transmitting = 1;
sc->sc_txmbuf = m;
fr.fr_r8 = (register_t)sc->sc_ioh.a1;
fr.fr_r9 = (register_t)sc->sc_txmbuf->m_data;
fr.fr_r10 = (register_t)sc->sc_txmbuf->m_len;
fr.fr_r11 = (register_t)&sc->sc_fiqstate;
fiq_setregs(&fr);
sc->sc_fiqstate.efs_tx_curmbuf = sc->sc_txmbuf;
fiq_downgrade_handler = eca_tx_downgrade;
/* Read and clear Tx status. */
bus_space_read_1(iot, ioh, MC6854_SR1);
bus_space_write_1(iot, ioh, MC6854_CR2,
sc->sc_cr2 | MC6854_CR2_CLR_TX_ST);
sc->sc_cr1 = MC6854_CR1_TIE;
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1 |
MC6854_CR1_DISCONTINUE);
ioc_fiq_setmask(IOC_FIQ_BIT(FIQ_EFIQ));
}
static void
eca_tx_downgrade(void)
{
struct eca_softc *sc = eca_fiqowner;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
int sr1;
char buf[128];
KASSERT(sc->sc_transmitting);
sc->sc_cr2 = 0;
if (__predict_true(sc->sc_fiqstate.efs_tx_curmbuf == NULL)) {
/* Entire frame got transmitted. */
} else {
sr1 = bus_space_read_1(iot, ioh, MC6854_SR1);
if (sr1 & MC6854_SR1_TXU)
log(LOG_ERR, "%s: Tx underrun\n", sc->sc_dev.dv_xname);
else if (sr1 & MC6854_SR1_NCTS)
log(LOG_WARNING, "%s: collision\n",
sc->sc_dev.dv_xname);
else {
log(LOG_ERR, "%s: incomplete transmission\n",
sc->sc_dev.dv_xname);
bitmask_snprintf(sr1, MC6854_SR1_BITS, buf, 128);
log(LOG_ERR, "%s: SR1 = %s\n",
sc->sc_dev.dv_xname, buf);
}
bus_space_write_1(iot, ioh, MC6854_CR2,
sc->sc_cr2 | MC6854_CR2_CLR_TX_ST);
}
sc->sc_txmbuf = NULL;
/* Code from eca_init_rx_hard(). */
sc->sc_cr1 = MC6854_CR1_RIE;
fiq_downgrade_handler = eca_rx_downgrade;
sc->sc_transmitting = 0;
eca_fiqowner = sc;
ioc_fiq_setmask(IOC_FIQ_BIT(FIQ_EFIQ));
/* End code from eca_init_rx_hard(). */
softintr_schedule(sc->sc_tx_soft);
}
/*
* Low-priority soft interrupt taken after a frame's been transmitted.
*/
static void
eca_txdone(void *arg)
{
struct eca_softc *sc = arg;
struct ifnet *ifp = &sc->sc_ec.ec_if;
m_freem(sc->sc_txmbuf);
sc->sc_txmbuf = NULL;
ifp->if_flags &= ~IFF_OACTIVE;
ifp->if_start(ifp);
}
/*
* Set up the Rx buffer for the interface.
* flags is M_WAIT or M_DONTWAIT. Returns an errno or 0 for success.
*/
static int
eca_init_rxbuf(struct eca_softc *sc, int flags)
{
struct mbuf *m, *n;
size_t totlen;
/*
* The Rx buffer takes the form of a chain of mbufs, set up as
* if they contain data already. The FIQ handler is
* responsible for filling the marked space, and indicating
* how much it's put in there.
*/
totlen = 0;
m = n = NULL;
while (totlen < sc->sc_ec.ec_if.if_mtu + ECO_HDR_LEN) {
MGETHDR(m, flags, MT_DATA);
if (m == NULL)
return ENOBUFS;
MCLGET(m, flags);
if ((m->m_flags & M_EXT) == 0) {
m_freem(m);
return ENOBUFS;
}
/* XXX may want to tweak for payload alignment here. */
m->m_len = m->m_ext.ext_size;
m->m_next = n;
totlen += m->m_len;
n = m;
}
sc->sc_rcvmbuf = m;
return 0;
}
/*
* Set up the software state necessary for reception, but don't
* actually start receoption. Pushing the state into the hardware is
* left to eca_init_rx_hard() the Tx FIQ handler.
*/
void
eca_init_rx_soft(struct eca_softc *sc)
{
struct ifnet *ifp = &sc->sc_ec.ec_if;
struct fiqregs *fr = &sc->sc_fiqstate.efs_rx_fiqregs;
memset(fr, 0, sizeof(*fr));
fr->fr_r8 = (register_t)sc->sc_ioh.a1;
fr->fr_r9 = (register_t)sc->sc_rcvmbuf->m_data;
fr->fr_r10 = (register_t)ECO_ADDR_LEN;
fr->fr_r11 = (register_t)&sc->sc_fiqstate;
sc->sc_fiqstate.efs_rx_curmbuf = sc->sc_rcvmbuf;
sc->sc_fiqstate.efs_rx_flags = 0;
sc->sc_fiqstate.efs_rx_myaddr = CLLADDR(ifp->if_sadl)[0];
}
/*
* Copy state set up by eca_init_rx_soft into the hardware, and reset
* the FIQ handler as appropriate.
*
* This code is functionally duplicated across the Tx FIQ handler and
* eca_tx_downgrade(). Keep them in sync!
*/
void
eca_init_rx_hard(struct eca_softc *sc)
{
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
struct fiqregs *fr = &sc->sc_fiqstate.efs_rx_fiqregs;
sc->sc_fiqstate.efs_fiqhandler = eca_fiqhandler_rx;
sc->sc_transmitting = 0;
sc->sc_cr1 = MC6854_CR1_RIE;
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1);
fiq_setregs(fr);
fiq_downgrade_handler = eca_rx_downgrade;
eca_fiqowner = sc;
ioc_fiq_setmask(IOC_FIQ_BIT(FIQ_EFIQ));
}
/*
* Set up the chip and FIQ handler for reception. Assumes the Rx buffer is
* set up already by eca_init_rxbuf().
*/
void
eca_init_rx(struct eca_softc *sc)
{
eca_init_rx_soft(sc);
eca_init_rx_hard(sc);
}
static void
eca_stop(struct ifnet *ifp, int disable)
{
struct eca_softc *sc = ifp->if_softc;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
ifp->if_flags &= ~IFF_RUNNING;
eco_stop(ifp, disable);
/* Interrupts disabled, no DMA, hold Tx and Rx in reset. */
sc->sc_cr1 = MC6854_CR1_RX_RS | MC6854_CR1_TX_RS;
bus_space_write_1(iot, ioh, MC6854_CR1, sc->sc_cr1);
ioc_fiq_setmask(0);
fiq_downgrade_handler = NULL;
eca_fiqowner = NULL;
fiq_release(&sc->sc_fiqhandler);
if (sc->sc_rcvmbuf != NULL) {
m_freem(sc->sc_rcvmbuf);
sc->sc_rcvmbuf = NULL;
}
}
/*
* This is a FIQ downgrade handler, and as such is entered at IPL_HIGH with
* FIQs disabled (but still owned by us).
*/
static void
eca_rx_downgrade(void)
{
struct eca_softc *sc = eca_fiqowner;
sc->sc_sr2 = bus_space_read_1(sc->sc_iot, sc->sc_ioh, MC6854_SR2);
softintr_schedule(sc->sc_rx_soft);
}
/*
* eca_gotframe() is called if there's something interesting on
* reception. The receiver is turned off now -- it's up to us to
* start it again.
*/
static void
eca_gotframe(void *arg)
{
struct eca_softc *sc = arg;
struct ifnet *ifp = &sc->sc_ec.ec_if;
bus_space_tag_t iot = sc->sc_iot;
bus_space_handle_t ioh = sc->sc_ioh;
struct fiqregs fr;
int sr2;
struct mbuf *m, *mtail, *n, *reply;
reply = NULL;
sr2 = sc->sc_sr2;
/* 1: Is there a valid frame waiting? */
if ((sr2 & MC6854_SR2_FV) && !(sr2 & MC6854_SR2_OVRN) &&
sc->sc_fiqstate.efs_rx_curmbuf != NULL) {
fiq_getregs(&fr);
m = sc->sc_rcvmbuf;
mtail = sc->sc_fiqstate.efs_rx_curmbuf;
/*
* Before we process this buffer, make sure we can get
* a new one.
*/
if (eca_init_rxbuf(sc, M_DONTWAIT) == 0) {
ifp->if_ipackets++; /* XXX packet vs frame? */
/* Trim the tail of the mbuf chain. */
mtail->m_len = (void *)(fr.fr_r9) - mtail->m_data;
m_freem(mtail->m_next);
mtail->m_next = NULL;
/* Set up the header of the chain. */
m->m_pkthdr.rcvif = ifp;
m->m_pkthdr.len = 0;
for (n = m; n != NULL; n = n->m_next)
m->m_pkthdr.len += n->m_len;
reply = eco_inputframe(ifp, m);
} else
ifp->if_iqdrops++;
}
/* 2: Are there any errors waiting? */
if (sr2 & MC6854_SR2_OVRN) {
fiq_getregs(&fr);
mtail = sc->sc_fiqstate.efs_rx_curmbuf;
log(LOG_ERR, "%s: Rx overrun (state = %d, len = %ld)\n",
sc->sc_dev.dv_xname, sc->sc_ec.ec_state,
(void *)(fr.fr_r9) - mtail->m_data);
ifp->if_ierrors++;
/* Discard the rest of the frame. */
if (!sc->sc_transmitting)
bus_space_write_1(iot, ioh, MC6854_CR1,
sc->sc_cr1 | MC6854_CR1_DISCONTINUE);
} else if (sr2 & MC6854_SR2_RXABT) {
log(LOG_NOTICE, "%s: Rx abort\n", sc->sc_dev.dv_xname);
ifp->if_ierrors++;
} else if (sr2 & MC6854_SR2_ERR) {
log(LOG_NOTICE, "%s: CRC error\n", sc->sc_dev.dv_xname);
ifp->if_ierrors++;
}
if (__predict_false(sr2 & MC6854_SR2_NDCD)) {
log(LOG_ERR, "%s: No clock\n", sc->sc_dev.dv_xname);
ifp->if_ierrors++;
}
if (sc->sc_fiqstate.efs_rx_curmbuf == NULL) {
log(LOG_NOTICE, "%s: Oversized frame\n", sc->sc_dev.dv_xname);
ifp->if_ierrors++;
/* Discard the rest of the frame. */
if (!sc->sc_transmitting)
bus_space_write_1(iot, ioh, MC6854_CR1,
sc->sc_cr1 | MC6854_CR1_DISCONTINUE);
}
bus_space_write_1(iot, ioh, MC6854_CR2,
sc->sc_cr2 | MC6854_CR2_CLR_RX_ST);
if (reply) {
KASSERT(sc->sc_fiqstate.efs_rx_flags & ERXF_FLAGFILL);
eca_init_rx_soft(sc);
eca_txframe(ifp, reply);
} else {
/* KASSERT(!sc->sc_transmitting); */
if (sc->sc_fiqstate.efs_rx_flags & ERXF_FLAGFILL)
/* Stop flag-filling: we have nothing to send. */
bus_space_write_1(iot, ioh, MC6854_CR2,
sc->sc_cr2);
/* Set the ADLC up to receive the next frame. */
eca_init_rx(sc);
/* 3: Is the network idle now? */
if (sr2 & MC6854_SR2_RX_IDLE)
eco_inputidle(ifp);
}
}