* Copyright (c) 2001 Rafal K. Boni

/* $NetBSD: if_sq.c,v 1.60 2024/07/05 04:31:50 rin Exp $ */

/*
* Copyright (c) 2001 Rafal K. Boni
* Copyright (c) 1998, 1999, 2000 The NetBSD Foundation, Inc.
* All rights reserved.
*
* Portions of this code are derived from software contributed to The
* NetBSD Foundation by Jason R. Thorpe of the Numerical Aerospace
* Simulation Facility, NASA Ames Research Center.
*
* 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/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: if_sq.c,v 1.60 2024/07/05 04:31:50 rin Exp $");

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/callout.h>
#include <sys/mbuf.h>
#include <sys/kernel.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/syslog.h>

#include <uvm/uvm_extern.h>

#include <machine/endian.h>

#include <net/if.h>
#include <net/if_dl.h>
#include <net/if_media.h>
#include <net/if_ether.h>

#include <net/bpf.h>

#include <sys/bus.h>
#include <machine/intr.h>
#include <machine/sysconf.h>

#include <dev/ic/seeq8003reg.h>

#include <sgimips/hpc/sqvar.h>
#include <sgimips/hpc/hpcvar.h>
#include <sgimips/hpc/hpcreg.h>

#include <dev/arcbios/arcbios.h>
#include <dev/arcbios/arcbiosvar.h>

#define static

/*
* Short TODO list:
* (1) Do counters for bad-RX packets.
* (2) Allow multi-segment transmits, instead of copying to a single,
* contiguous mbuf.
* (3) Verify sq_stop() turns off enough stuff; I was still getting
* seeq interrupts after sq_stop().
* (4) Implement EDLC modes: especially packet auto-pad and simplex
* mode.
* (5) Should the driver filter out its own transmissions in non-EDLC
* mode?
* (6) Multicast support -- multicast filter, address management, ...
* (7) Deal with RB0 (recv buffer overflow) on reception. Will need
* to figure out if RB0 is read-only as stated in one spot in the
* HPC spec or read-write (ie, is the 'write a one to clear it')
* the correct thing?
*/

#if defined(SQ_DEBUG)
int sq_debug = 0;
#define SQ_DPRINTF(x) if (sq_debug) printf x
#else
#define SQ_DPRINTF(x)
#endif

static int sq_match(device_t, cfdata_t, void *);
static void sq_attach(device_t, device_t, void *);
static int sq_init(struct ifnet *);
static void sq_start(struct ifnet *);
static void sq_stop(struct ifnet *, int);
static void sq_watchdog(struct ifnet *);
static int sq_ioctl(struct ifnet *, u_long, void *);

static void sq_set_filter(struct sq_softc *);
static int sq_intr(void *);
static int sq_rxintr(struct sq_softc *);
static int sq_txintr(struct sq_softc *);
static void sq_txring_hpc1(struct sq_softc *);
static void sq_txring_hpc3(struct sq_softc *);
static void sq_reset(struct sq_softc *);
static int sq_add_rxbuf(struct sq_softc *, int);
static void sq_dump_buffer(paddr_t, psize_t);
static void sq_trace_dump(struct sq_softc *);

CFATTACH_DECL_NEW(sq, sizeof(struct sq_softc),
sq_match, sq_attach, NULL, NULL);

#define ETHER_PAD_LEN (ETHER_MIN_LEN - ETHER_CRC_LEN)

#define sq_seeq_read(sc, off) \
bus_space_read_1(sc->sc_regt, sc->sc_regh, (off << 2) + 3)
#define sq_seeq_write(sc, off, val) \
bus_space_write_1(sc->sc_regt, sc->sc_regh, (off << 2) + 3, val)

#define sq_hpc_read(sc, off) \
bus_space_read_4(sc->sc_hpct, sc->sc_hpch, off)
#define sq_hpc_write(sc, off, val) \
bus_space_write_4(sc->sc_hpct, sc->sc_hpch, off, val)

/* MAC address offset for non-onboard implementations */
#define SQ_HPC_EEPROM_ENADDR 250

#define SGI_OUI_0 0x08
#define SGI_OUI_1 0x00
#define SGI_OUI_2 0x69

static int
sq_match(device_t parent, cfdata_t cf, void *aux)
{
struct hpc_attach_args *ha = aux;

if (strcmp(ha->ha_name, cf->cf_name) == 0) {
vaddr_t reset, txstat;

reset = MIPS_PHYS_TO_KSEG1(ha->ha_sh +
ha->ha_dmaoff + ha->hpc_regs->enetr_reset);
txstat = MIPS_PHYS_TO_KSEG1(ha->ha_sh +
ha->ha_devoff + (SEEQ_TXSTAT << 2));

if (platform.badaddr((void *)reset, sizeof(reset)))
return 0;

*(volatile uint32_t *)reset = 0x1;
delay(20);
*(volatile uint32_t *)reset = 0x0;

if (platform.badaddr((void *)txstat, sizeof(txstat)))
return 0;

if ((*(volatile uint32_t *)txstat & 0xff) == TXSTAT_OLDNEW)
return 1;
}

return 0;
}

static void
sq_attach(device_t parent, device_t self, void *aux)
{
int i, err;
const char* macaddr;
struct sq_softc *sc = device_private(self);
struct hpc_attach_args *haa = aux;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;

sc->sc_dev = self;
sc->sc_hpct = haa->ha_st;
sc->hpc_regs = haa->hpc_regs; /* HPC register definitions */

if ((err = bus_space_subregion(haa->ha_st, haa->ha_sh,
haa->ha_dmaoff, sc->hpc_regs->enet_regs_size,
&sc->sc_hpch)) != 0) {
printf(": unable to map HPC DMA registers, error = %d\n", err);
goto fail_0;
}

sc->sc_regt = haa->ha_st;
if ((err = bus_space_subregion(haa->ha_st, haa->ha_sh,
haa->ha_devoff, sc->hpc_regs->enet_devregs_size,
&sc->sc_regh)) != 0) {
printf(": unable to map Seeq registers, error = %d\n", err);
goto fail_0;
}

sc->sc_dmat = haa->ha_dmat;

if ((err = bus_dmamem_alloc(sc->sc_dmat, sizeof(struct sq_control),
PAGE_SIZE, PAGE_SIZE, &sc->sc_cdseg, 1, &sc->sc_ncdseg,
BUS_DMA_NOWAIT)) != 0) {
printf(": unable to allocate control data, error = %d\n", err);
goto fail_0;
}

if ((err = bus_dmamem_map(sc->sc_dmat, &sc->sc_cdseg, sc->sc_ncdseg,
sizeof(struct sq_control), (void **)&sc->sc_control,
BUS_DMA_NOWAIT | BUS_DMA_COHERENT)) != 0) {
printf(": unable to map control data, error = %d\n", err);
goto fail_1;
}

if ((err = bus_dmamap_create(sc->sc_dmat,
sizeof(struct sq_control), 1, sizeof(struct sq_control), PAGE_SIZE,
BUS_DMA_NOWAIT, &sc->sc_cdmap)) != 0) {
printf(": unable to create DMA map for control data, error "
"= %d\n", err);
goto fail_2;
}

if ((err = bus_dmamap_load(sc->sc_dmat, sc->sc_cdmap,
sc->sc_control, sizeof(struct sq_control), NULL,
BUS_DMA_NOWAIT)) != 0) {
printf(": unable to load DMA map for control data, error "
"= %d\n", err);
goto fail_3;
}

memset(sc->sc_control, 0, sizeof(struct sq_control));

/* Create transmit buffer DMA maps */
for (i = 0; i < SQ_NTXDESC; i++) {
if ((err = bus_dmamap_create(sc->sc_dmat,
MCLBYTES, 1, MCLBYTES, 0,
BUS_DMA_NOWAIT, &sc->sc_txmap[i])) != 0) {
printf(": unable to create tx DMA map %d, error = %d\n",
i, err);
goto fail_4;
}
}

/* Create receive buffer DMA maps */
for (i = 0; i < SQ_NRXDESC; i++) {
if ((err = bus_dmamap_create(sc->sc_dmat,
MCLBYTES, 1, MCLBYTES, 0,
BUS_DMA_NOWAIT, &sc->sc_rxmap[i])) != 0) {
printf(": unable to create rx DMA map %d, error = %d\n",
i, err);
goto fail_5;
}
}

/* Pre-allocate the receive buffers. */
for (i = 0; i < SQ_NRXDESC; i++) {
if ((err = sq_add_rxbuf(sc, i)) != 0) {
printf(": unable to allocate or map rx buffer %d\n,"
" error = %d\n", i, err);
goto fail_6;
}
}

memcpy(sc->sc_enaddr, &haa->hpc_eeprom[SQ_HPC_EEPROM_ENADDR],
ETHER_ADDR_LEN);

/*
* If our mac address is bogus, obtain it from ARCBIOS. This will
* be true of the onboard HPC3 on IP22, since there is no eeprom,
* but rather the DS1386 RTC's battery-backed ram is used.
*/
if (sc->sc_enaddr[0] != SGI_OUI_0 ||
sc->sc_enaddr[1] != SGI_OUI_1 ||
sc->sc_enaddr[2] != SGI_OUI_2) {
macaddr = arcbios_GetEnvironmentVariable("eaddr");
if (macaddr == NULL) {
printf(": unable to get MAC address!\n");
goto fail_6;
}
ether_aton_r(sc->sc_enaddr, sizeof(sc->sc_enaddr), macaddr);
}

evcnt_attach_dynamic(&sc->sq_intrcnt, EVCNT_TYPE_INTR, NULL,
device_xname(self), "intr");

if ((cpu_intr_establish(haa->ha_irq, IPL_NET, sq_intr, sc)) == NULL) {
printf(": unable to establish interrupt!\n");
goto fail_6;
}

/* Reset the chip to a known state. */
sq_reset(sc);

/*
* Determine if we're an 8003 or 80c03 by setting the first
* MAC address register to non-zero, and then reading it back.
* If it's zero, we have an 80c03, because we will have read
* the TxCollLSB register.
*/
sq_seeq_write(sc, SEEQ_TXCOLLS0, 0xa5);
if (sq_seeq_read(sc, SEEQ_TXCOLLS0) == 0)
sc->sc_type = SQ_TYPE_80C03;
else
sc->sc_type = SQ_TYPE_8003;
sq_seeq_write(sc, SEEQ_TXCOLLS0, 0x00);

printf(": SGI Seeq %s\n",
sc->sc_type == SQ_TYPE_80C03 ? "80c03" : "8003");

printf("%s: Ethernet address %s\n",
device_xname(self), ether_sprintf(sc->sc_enaddr));

strcpy(ifp->if_xname, device_xname(self));
ifp->if_softc = sc;
ifp->if_mtu = ETHERMTU;
ifp->if_init = sq_init;
ifp->if_stop = sq_stop;
ifp->if_start = sq_start;
ifp->if_ioctl = sq_ioctl;
ifp->if_watchdog = sq_watchdog;
ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST;
IFQ_SET_READY(&ifp->if_snd);

if_attach(ifp);
if_deferred_start_init(ifp, NULL);
ether_ifattach(ifp, sc->sc_enaddr);

memset(&sc->sq_trace, 0, sizeof(sc->sq_trace));
/* Done! */
return;

/*
* Free any resources we've allocated during the failed attach
* attempt. Do this in reverse order and fall through.
*/
fail_6:
for (i = 0; i < SQ_NRXDESC; i++) {
if (sc->sc_rxmbuf[i] != NULL) {
bus_dmamap_unload(sc->sc_dmat, sc->sc_rxmap[i]);
m_freem(sc->sc_rxmbuf[i]);
}
}
fail_5:
for (i = 0; i < SQ_NRXDESC; i++) {
if (sc->sc_rxmap[i] != NULL)
bus_dmamap_destroy(sc->sc_dmat, sc->sc_rxmap[i]);
}
fail_4:
for (i = 0; i < SQ_NTXDESC; i++) {
if (sc->sc_txmap[i] != NULL)
bus_dmamap_destroy(sc->sc_dmat, sc->sc_txmap[i]);
}
bus_dmamap_unload(sc->sc_dmat, sc->sc_cdmap);
fail_3:
bus_dmamap_destroy(sc->sc_dmat, sc->sc_cdmap);
fail_2:
bus_dmamem_unmap(sc->sc_dmat,
(void *)sc->sc_control, sizeof(struct sq_control));
fail_1:
bus_dmamem_free(sc->sc_dmat, &sc->sc_cdseg, sc->sc_ncdseg);
fail_0:
return;
}

/* Set up data to get the interface up and running. */
int
sq_init(struct ifnet *ifp)
{
int i;
struct sq_softc *sc = ifp->if_softc;

/* Cancel any in-progress I/O */
sq_stop(ifp, 0);

sc->sc_nextrx = 0;

sc->sc_nfreetx = SQ_NTXDESC;
sc->sc_nexttx = sc->sc_prevtx = 0;

SQ_TRACE(SQ_RESET, sc, 0, 0);

/* Set into 8003 mode, bank 0 to program ethernet address */
sq_seeq_write(sc, SEEQ_TXCMD, TXCMD_BANK0);

/* Now write the address */
for (i = 0; i < ETHER_ADDR_LEN; i++)
sq_seeq_write(sc, i, sc->sc_enaddr[i]);

sc->sc_rxcmd =
RXCMD_IE_CRC |
RXCMD_IE_DRIB |
RXCMD_IE_SHORT |
RXCMD_IE_END |
RXCMD_IE_GOOD;

/*
* Set the receive filter -- this will add some bits to the
* prototype RXCMD register. Do this before setting the
* transmit config register, since we might need to switch
* banks.
*/
sq_set_filter(sc);

/* Set up Seeq transmit command register */
sq_seeq_write(sc, SEEQ_TXCMD,
TXCMD_IE_UFLOW |
TXCMD_IE_COLL |
TXCMD_IE_16COLL |
TXCMD_IE_GOOD);

/* Now write the receive command register. */
sq_seeq_write(sc, SEEQ_RXCMD, sc->sc_rxcmd);

/*
* Set up HPC ethernet PIO and DMA configurations.
*
* The PROM appears to do most of this for the onboard HPC3, but
* not for the Challenge S's IOPLUS chip. We copy how the onboard
* chip is configured and assume that it's correct for both.
*/
if (sc->hpc_regs->revision == 3) {
uint32_t dmareg, pioreg;

pioreg =
HPC3_ENETR_PIOCFG_P1(1) |
HPC3_ENETR_PIOCFG_P2(6) |
HPC3_ENETR_PIOCFG_P3(1);

dmareg =
HPC3_ENETR_DMACFG_D1(6) |
HPC3_ENETR_DMACFG_D2(2) |
HPC3_ENETR_DMACFG_D3(0) |
HPC3_ENETR_DMACFG_FIX_RXDC |
HPC3_ENETR_DMACFG_FIX_INTR |
HPC3_ENETR_DMACFG_FIX_EOP |
HPC3_ENETR_DMACFG_TIMEOUT;

sq_hpc_write(sc, HPC3_ENETR_PIOCFG, pioreg);
sq_hpc_write(sc, HPC3_ENETR_DMACFG, dmareg);
}

/* Pass the start of the receive ring to the HPC */
sq_hpc_write(sc, sc->hpc_regs->enetr_ndbp, SQ_CDRXADDR(sc, 0));

/* And turn on the HPC ethernet receive channel */
sq_hpc_write(sc, sc->hpc_regs->enetr_ctl,
sc->hpc_regs->enetr_ctl_active);

/*
* Turn off delayed receive interrupts on HPC1.
* (see Hollywood HPC Specification 2.1.4.3)
*/
if (sc->hpc_regs->revision != 3)
sq_hpc_write(sc, HPC1_ENET_INTDELAY, HPC1_ENET_INTDELAY_OFF);

ifp->if_flags |= IFF_RUNNING;

return 0;
}

static void
sq_set_filter(struct sq_softc *sc)
{
struct ethercom *ec = &sc->sc_ethercom;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;
struct ether_multi *enm;
struct ether_multistep step;

/*
* Check for promiscuous mode. Also implies
* all-multicast.
*/
if (ifp->if_flags & IFF_PROMISC) {
sc->sc_rxcmd |= RXCMD_REC_ALL;
ifp->if_flags |= IFF_ALLMULTI;
return;
}

/*
* The 8003 has no hash table. If we have any multicast
* addresses on the list, enable reception of all multicast
* frames.
*
* XXX The 80c03 has a hash table. We should use it.
*/

ETHER_FIRST_MULTI(step, ec, enm);

if (enm == NULL) {
sc->sc_rxcmd &= ~RXCMD_REC_MASK;
sc->sc_rxcmd |= RXCMD_REC_BROAD;

ifp->if_flags &= ~IFF_ALLMULTI;
return;
}

sc->sc_rxcmd |= RXCMD_REC_MULTI;
ifp->if_flags |= IFF_ALLMULTI;
}

int
sq_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
int s, error = 0;

SQ_TRACE(SQ_IOCTL, (struct sq_softc *)ifp->if_softc, 0, 0);

s = splnet();

error = ether_ioctl(ifp, cmd, data);
if (error == ENETRESET) {
/*
* Multicast list has changed; set the hardware filter
* accordingly.
*/
if (ifp->if_flags & IFF_RUNNING)
error = sq_init(ifp);
else
error = 0;
}

splx(s);
return error;
}

void
sq_start(struct ifnet *ifp)
{
struct sq_softc *sc = ifp->if_softc;
uint32_t status;
struct mbuf *m0, *m;
bus_dmamap_t dmamap;
int err, totlen, nexttx, firsttx, lasttx = -1, ofree, seg;

if ((ifp->if_flags & IFF_RUNNING) == 0)
return;

/*
* Remember the previous number of free descriptors and
* the first descriptor we'll use.
*/
ofree = sc->sc_nfreetx;
firsttx = sc->sc_nexttx;

/*
* Loop through the send queue, setting up transmit descriptors
* until we drain the queue, or use up all available transmit
* descriptors.
*/
while (sc->sc_nfreetx != 0) {
/*
* Grab a packet off the queue.
*/
IFQ_POLL(&ifp->if_snd, m0);
if (m0 == NULL)
break;
m = NULL;

dmamap = sc->sc_txmap[sc->sc_nexttx];

/*
* Load the DMA map. If this fails, the packet either
* didn't fit in the allotted number of segments, or we were
* short on resources. In this case, we'll copy and try
* again.
* Also copy it if we need to pad, so that we are sure there
* is room for the pad buffer.
* XXX the right way of doing this is to use a static buffer
* for padding and adding it to the transmit descriptor (see
* sys/dev/pci/if_tl.c for example). We can't do this here yet
* because we can't send packets with more than one fragment.
*/
if (m0->m_pkthdr.len < ETHER_PAD_LEN ||
bus_dmamap_load_mbuf(sc->sc_dmat, dmamap, m0,
BUS_DMA_NOWAIT) != 0) {
MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL) {
printf("%s: unable to allocate Tx mbuf\n",
device_xname(sc->sc_dev));
break;
}
if (m0->m_pkthdr.len > MHLEN) {
MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
printf("%s: unable to allocate Tx "
"cluster\n",
device_xname(sc->sc_dev));
m_freem(m);
break;
}
}

m_copydata(m0, 0, m0->m_pkthdr.len, mtod(m, void *));
if (m0->m_pkthdr.len < ETHER_PAD_LEN) {
memset(mtod(m, char *) + m0->m_pkthdr.len, 0,
ETHER_PAD_LEN - m0->m_pkthdr.len);
m->m_pkthdr.len = m->m_len = ETHER_PAD_LEN;
} else
m->m_pkthdr.len = m->m_len = m0->m_pkthdr.len;

if ((err = bus_dmamap_load_mbuf(sc->sc_dmat, dmamap,
m, BUS_DMA_NOWAIT)) != 0) {
printf("%s: unable to load Tx buffer, "
"error = %d\n",
device_xname(sc->sc_dev), err);
break;
}
}

/*
* Ensure we have enough descriptors free to describe
* the packet.
*/
if (dmamap->dm_nsegs > sc->sc_nfreetx) {
/*
* Not enough free descriptors to transmit this
* packet. We haven't committed to anything yet,
* so just unload the DMA map, put the packet
* back on the queue, and punt.
*
* XXX We could allocate an mbuf and copy, but
* XXX it is worth it?
*/
bus_dmamap_unload(sc->sc_dmat, dmamap);
m_freem(m);
break;
}

IFQ_DEQUEUE(&ifp->if_snd, m0);
/*
* Pass the packet to any BPF listeners.
*/
bpf_mtap(ifp, m0, BPF_D_OUT);
if (m != NULL) {
m_freem(m0);
m0 = m;
}

/*
* WE ARE NOW COMMITTED TO TRANSMITTING THE PACKET.
*/

SQ_TRACE(SQ_ENQUEUE, sc, sc->sc_nexttx, 0);

/* Sync the DMA map. */
bus_dmamap_sync(sc->sc_dmat, dmamap, 0, dmamap->dm_mapsize,
BUS_DMASYNC_PREWRITE);

/*
* Initialize the transmit descriptors.
*/
for (nexttx = sc->sc_nexttx, seg = 0, totlen = 0;
seg < dmamap->dm_nsegs;
seg++, nexttx = SQ_NEXTTX(nexttx)) {
if (sc->hpc_regs->revision == 3) {
sc->sc_txdesc[nexttx].hpc3_hdd_bufptr =
dmamap->dm_segs[seg].ds_addr;
sc->sc_txdesc[nexttx].hpc3_hdd_ctl =
dmamap->dm_segs[seg].ds_len;
} else {
sc->sc_txdesc[nexttx].hpc1_hdd_bufptr =
dmamap->dm_segs[seg].ds_addr;
sc->sc_txdesc[nexttx].hpc1_hdd_ctl =
dmamap->dm_segs[seg].ds_len;
}
sc->sc_txdesc[nexttx].hdd_descptr =
SQ_CDTXADDR(sc, SQ_NEXTTX(nexttx));
lasttx = nexttx;
totlen += dmamap->dm_segs[seg].ds_len;
}

/* Last descriptor gets end-of-packet */
KASSERT(lasttx != -1);
if (sc->hpc_regs->revision == 3)
sc->sc_txdesc[lasttx].hpc3_hdd_ctl |=
HPC3_HDD_CTL_EOPACKET;
else
sc->sc_txdesc[lasttx].hpc1_hdd_ctl |=
HPC1_HDD_CTL_EOPACKET;

SQ_DPRINTF(("%s: transmit %d-%d, len %d\n",
device_xname(sc->sc_dev), sc->sc_nexttx, lasttx, totlen));

if (ifp->if_flags & IFF_DEBUG) {
printf(" transmit chain:\n");
for (seg = sc->sc_nexttx;; seg = SQ_NEXTTX(seg)) {
printf(" descriptor %d:\n", seg);
printf(" hdd_bufptr: 0x%08x\n",
(sc->hpc_regs->revision == 3) ?
sc->sc_txdesc[seg].hpc3_hdd_bufptr :
sc->sc_txdesc[seg].hpc1_hdd_bufptr);
printf(" hdd_ctl: 0x%08x\n",
(sc->hpc_regs->revision == 3) ?
sc->sc_txdesc[seg].hpc3_hdd_ctl:
sc->sc_txdesc[seg].hpc1_hdd_ctl);
printf(" hdd_descptr: 0x%08x\n",
sc->sc_txdesc[seg].hdd_descptr);

if (seg == lasttx)
break;
}
}

/* Sync the descriptors we're using. */
SQ_CDTXSYNC(sc, sc->sc_nexttx, dmamap->dm_nsegs,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

/* Store a pointer to the packet so we can free it later */
sc->sc_txmbuf[sc->sc_nexttx] = m0;

/* Advance the tx pointer. */
sc->sc_nfreetx -= dmamap->dm_nsegs;
sc->sc_nexttx = nexttx;
}

if (sc->sc_nfreetx != ofree) {
SQ_DPRINTF(("%s: %d packets enqueued, first %d, INTR on %d\n",
device_xname(sc->sc_dev), lasttx - firsttx + 1,
firsttx, lasttx));

/*
* Cause a transmit interrupt to happen on the
* last packet we enqueued, mark it as the last
* descriptor.
*
* HPC1_HDD_CTL_INTR will generate an interrupt on
* HPC1. HPC3 requires HPC3_HDD_CTL_EOPACKET in
* addition to HPC3_HDD_CTL_INTR to interrupt.
*/
KASSERT(lasttx != -1);
if (sc->hpc_regs->revision == 3) {
sc->sc_txdesc[lasttx].hpc3_hdd_ctl |=
HPC3_HDD_CTL_INTR | HPC3_HDD_CTL_EOCHAIN;
} else {
sc->sc_txdesc[lasttx].hpc1_hdd_ctl |= HPC1_HDD_CTL_INTR;
sc->sc_txdesc[lasttx].hpc1_hdd_bufptr |=
HPC1_HDD_CTL_EOCHAIN;
}

SQ_CDTXSYNC(sc, lasttx, 1,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

/*
* There is a potential race condition here if the HPC
* DMA channel is active and we try and either update
* the 'next descriptor' pointer in the HPC PIO space
* or the 'next descriptor' pointer in a previous desc-
* riptor.
*
* To avoid this, if the channel is active, we rely on
* the transmit interrupt routine noticing that there
* are more packets to send and restarting the HPC DMA
* engine, rather than mucking with the DMA state here.
*/
status = sq_hpc_read(sc, sc->hpc_regs->enetx_ctl);

if ((status & sc->hpc_regs->enetx_ctl_active) != 0) {
SQ_TRACE(SQ_ADD_TO_DMA, sc, firsttx, status);

/*
* NB: hpc3_hdd_ctl == hpc1_hdd_bufptr, and
* HPC1_HDD_CTL_EOCHAIN == HPC3_HDD_CTL_EOCHAIN
*/
sc->sc_txdesc[SQ_PREVTX(firsttx)].hpc3_hdd_ctl &=
~HPC3_HDD_CTL_EOCHAIN;

if (sc->hpc_regs->revision != 3)
sc->sc_txdesc[SQ_PREVTX(firsttx)].hpc1_hdd_ctl
&= ~HPC1_HDD_CTL_INTR;

SQ_CDTXSYNC(sc, SQ_PREVTX(firsttx), 1,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
} else if (sc->hpc_regs->revision == 3) {
SQ_TRACE(SQ_START_DMA, sc, firsttx, status);

sq_hpc_write(sc, HPC3_ENETX_NDBP, SQ_CDTXADDR(sc,
firsttx));

/* Kick DMA channel into life */
sq_hpc_write(sc, HPC3_ENETX_CTL, HPC3_ENETX_CTL_ACTIVE);
} else {
/*
* In the HPC1 case where transmit DMA is
* inactive, we can either kick off if
* the ring was previously empty, or call
* our transmit interrupt handler to
* figure out if the ring stopped short
* and restart at the right place.
*/
if (ofree == SQ_NTXDESC) {
SQ_TRACE(SQ_START_DMA, sc, firsttx, status);

sq_hpc_write(sc, HPC1_ENETX_NDBP,
SQ_CDTXADDR(sc, firsttx));
sq_hpc_write(sc, HPC1_ENETX_CFXBP,
SQ_CDTXADDR(sc, firsttx));
sq_hpc_write(sc, HPC1_ENETX_CBP,
SQ_CDTXADDR(sc, firsttx));

/* Kick DMA channel into life */
sq_hpc_write(sc, HPC1_ENETX_CTL,
HPC1_ENETX_CTL_ACTIVE);
} else
sq_txring_hpc1(sc);
}

/* Set a watchdog timer in case the chip flakes out. */
ifp->if_timer = 5;
}
}

void
sq_stop(struct ifnet *ifp, int disable)
{
int i;
struct sq_softc *sc = ifp->if_softc;

for (i = 0; i < SQ_NTXDESC; i++) {
if (sc->sc_txmbuf[i] != NULL) {
bus_dmamap_unload(sc->sc_dmat, sc->sc_txmap[i]);
m_freem(sc->sc_txmbuf[i]);
sc->sc_txmbuf[i] = NULL;
}
}

/* Clear Seeq transmit/receive command registers */
sq_seeq_write(sc, SEEQ_TXCMD, 0);
sq_seeq_write(sc, SEEQ_RXCMD, 0);

sq_reset(sc);

ifp->if_flags &= ~IFF_RUNNING;
ifp->if_timer = 0;
}

/* Device timeout/watchdog routine. */
void
sq_watchdog(struct ifnet *ifp)
{
uint32_t status;
struct sq_softc *sc = ifp->if_softc;

status = sq_hpc_read(sc, sc->hpc_regs->enetx_ctl);
log(LOG_ERR, "%s: device timeout (prev %d, next %d, free %d, "
"status %08x)\n", device_xname(sc->sc_dev), sc->sc_prevtx,
sc->sc_nexttx, sc->sc_nfreetx, status);

sq_trace_dump(sc);

memset(&sc->sq_trace, 0, sizeof(sc->sq_trace));
sc->sq_trace_idx = 0;

if_statinc(ifp, if_oerrors);

sq_init(ifp);
}

static void
sq_trace_dump(struct sq_softc *sc)
{
int i;
const char *act;

for (i = 0; i < sc->sq_trace_idx; i++) {
switch (sc->sq_trace[i].action) {
case SQ_RESET: act = "SQ_RESET"; break;
case SQ_ADD_TO_DMA: act = "SQ_ADD_TO_DMA"; break;
case SQ_START_DMA: act = "SQ_START_DMA"; break;
case SQ_DONE_DMA: act = "SQ_DONE_DMA"; break;
case SQ_RESTART_DMA: act = "SQ_RESTART_DMA"; break;
case SQ_TXINTR_ENTER: act = "SQ_TXINTR_ENTER"; break;
case SQ_TXINTR_EXIT: act = "SQ_TXINTR_EXIT"; break;
case SQ_TXINTR_BUSY: act = "SQ_TXINTR_BUSY"; break;
case SQ_IOCTL: act = "SQ_IOCTL"; break;
case SQ_ENQUEUE: act = "SQ_ENQUEUE"; break;
default: act = "UNKNOWN";
}

printf("%s: [%03d] action %-16s buf %03d free %03d "
"status %08x line %d\n", device_xname(sc->sc_dev), i, act,
sc->sq_trace[i].bufno, sc->sq_trace[i].freebuf,
sc->sq_trace[i].status, sc->sq_trace[i].line);
}
}

static int
sq_intr(void *arg)
{
struct sq_softc *sc = arg;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;
int handled = 0;
uint32_t stat;

stat = sq_hpc_read(sc, sc->hpc_regs->enetr_reset);

if ((stat & 2) == 0) {
SQ_DPRINTF(("%s: Unexpected interrupt!\n",
device_xname(sc->sc_dev)));
} else
sq_hpc_write(sc, sc->hpc_regs->enetr_reset, (stat | 2));

/*
* If the interface isn't running, the interrupt couldn't
* possibly have come from us.
*/
if ((ifp->if_flags & IFF_RUNNING) == 0)
return 0;

sc->sq_intrcnt.ev_count++;

/* Always check for received packets */
if (sq_rxintr(sc) != 0)
handled++;

/* Only handle transmit interrupts if we actually sent something */
if (sc->sc_nfreetx < SQ_NTXDESC) {
sq_txintr(sc);
handled++;
}

if (handled)
rnd_add_uint32(&sc->rnd_source, stat);
return handled;
}

static int
sq_rxintr(struct sq_softc *sc)
{
int count = 0;
struct mbuf* m;
int i, framelen;
uint8_t pktstat;
uint32_t status;
uint32_t ctl_reg;
int new_end, orig_end;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;

for (i = sc->sc_nextrx;; i = SQ_NEXTRX(i)) {
SQ_CDRXSYNC(sc, i,
BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

/*
* If this is a CPU-owned buffer, we're at the end of the list.
*/
if (sc->hpc_regs->revision == 3)
ctl_reg =
sc->sc_rxdesc[i].hpc3_hdd_ctl & HPC3_HDD_CTL_OWN;
else
ctl_reg =
sc->sc_rxdesc[i].hpc1_hdd_ctl & HPC1_HDD_CTL_OWN;

if (ctl_reg) {
#if defined(SQ_DEBUG)
uint32_t reg;

reg = sq_hpc_read(sc, sc->hpc_regs->enetr_ctl);
SQ_DPRINTF(("%s: rxintr: done at %d (ctl %08x)\n",
device_xname(sc->sc_dev), i, reg));
#endif
break;
}

count++;

m = sc->sc_rxmbuf[i];
framelen = m->m_ext.ext_size - 3;
if (sc->hpc_regs->revision == 3)
framelen -=
HPC3_HDD_CTL_BYTECNT(sc->sc_rxdesc[i].hpc3_hdd_ctl);
else
framelen -=
HPC1_HDD_CTL_BYTECNT(sc->sc_rxdesc[i].hpc1_hdd_ctl);

/* Now sync the actual packet data */
bus_dmamap_sync(sc->sc_dmat, sc->sc_rxmap[i], 0,
sc->sc_rxmap[i]->dm_mapsize, BUS_DMASYNC_POSTREAD);

pktstat = *((uint8_t *)m->m_data + framelen + 2);

if ((pktstat & RXSTAT_GOOD) == 0) {
if_statinc(ifp, if_ierrors);

if (pktstat & RXSTAT_OFLOW)
printf("%s: receive FIFO overflow\n",
device_xname(sc->sc_dev));

bus_dmamap_sync(sc->sc_dmat, sc->sc_rxmap[i], 0,
sc->sc_rxmap[i]->dm_mapsize, BUS_DMASYNC_PREREAD);
SQ_INIT_RXDESC(sc, i);
SQ_DPRINTF(("%s: sq_rxintr: buf %d no RXSTAT_GOOD\n",
device_xname(sc->sc_dev), i));
continue;
}

if (sq_add_rxbuf(sc, i) != 0) {
if_statinc(ifp, if_ierrors);
bus_dmamap_sync(sc->sc_dmat, sc->sc_rxmap[i], 0,
sc->sc_rxmap[i]->dm_mapsize, BUS_DMASYNC_PREREAD);
SQ_INIT_RXDESC(sc, i);
SQ_DPRINTF(("%s: sq_rxintr: buf %d sq_add_rxbuf() "
"failed\n", device_xname(sc->sc_dev), i));
continue;
}

m->m_data += 2;
m_set_rcvif(m, ifp);
m->m_pkthdr.len = m->m_len = framelen;

SQ_DPRINTF(("%s: sq_rxintr: buf %d len %d\n",
device_xname(sc->sc_dev), i, framelen));

if_percpuq_enqueue(ifp->if_percpuq, m);
}

/* If anything happened, move ring start/end pointers to new spot */
if (i != sc->sc_nextrx) {
/*
* NB: hpc3_hdd_ctl == hpc1_hdd_bufptr, and
* HPC1_HDD_CTL_EOCHAIN == HPC3_HDD_CTL_EOCHAIN
*/

new_end = SQ_PREVRX(i);
sc->sc_rxdesc[new_end].hpc3_hdd_ctl |= HPC3_HDD_CTL_EOCHAIN;
SQ_CDRXSYNC(sc, new_end,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

orig_end = SQ_PREVRX(sc->sc_nextrx);
sc->sc_rxdesc[orig_end].hpc3_hdd_ctl &= ~HPC3_HDD_CTL_EOCHAIN;
SQ_CDRXSYNC(sc, orig_end,
BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);

sc->sc_nextrx = i;
}

status = sq_hpc_read(sc, sc->hpc_regs->enetr_ctl);

/* If receive channel is stopped, restart it... */
if ((status & sc->hpc_regs->enetr_ctl_active) == 0) {
/* Pass the start of the receive ring to the HPC */
sq_hpc_write(sc, sc->hpc_regs->enetr_ndbp,
SQ_CDRXADDR(sc, sc->sc_nextrx));

/* And turn on the HPC ethernet receive channel */
sq_hpc_write(sc, sc->hpc_regs->enetr_ctl,
sc->hpc_regs->enetr_ctl_active);
}

return count;
}

static int
sq_txintr(struct sq_softc *sc)
{
int shift = 0;
uint32_t status, tmp;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;

if (sc->hpc_regs->revision != 3)
shift = 16;

status = sq_hpc_read(sc, sc->hpc_regs->enetx_ctl) >> shift;

SQ_TRACE(SQ_TXINTR_ENTER, sc, sc->sc_prevtx, status);

net_stat_ref_t nsr = IF_STAT_GETREF(ifp);
tmp = (sc->hpc_regs->enetx_ctl_active >> shift) | TXSTAT_GOOD;
if ((status & tmp) == 0) {
if (status & TXSTAT_COLL)
if_statinc_ref(ifp, nsr, if_collisions);

if (status & TXSTAT_UFLOW) {
printf("%s: transmit underflow\n",
device_xname(sc->sc_dev));
if_statinc_ref(ifp, nsr, if_oerrors);
}

if (status & TXSTAT_16COLL) {
printf("%s: max collisions reached\n",
device_xname(sc->sc_dev));
if_statinc_ref(ifp, nsr, if_oerrors);
if_statadd_ref(ifp, nsr, if_collisions, 16);
}
}
IF_STAT_PUTREF(ifp);

/* prevtx now points to next xmit packet not yet finished */
if (sc->hpc_regs->revision == 3)
sq_txring_hpc3(sc);
else
sq_txring_hpc1(sc);

/* If all packets have left the coop, cancel watchdog */
if (sc->sc_nfreetx == SQ_NTXDESC)
ifp->if_timer = 0;

SQ_TRACE(SQ_TXINTR_EXIT, sc, sc->sc_prevtx, status);
if_schedule_deferred_start(ifp);

return 1;
}

/*
* Reclaim used transmit descriptors and restart the transmit DMA
* engine if necessary.
*/
static void
sq_txring_hpc1(struct sq_softc *sc)
{
/*
* HPC1 doesn't tag transmitted descriptors, however,
* the NDBP register points to the next descriptor that
* has not yet been processed. If DMA is not in progress,
* we can safely reclaim all descriptors up to NDBP, and,
* if necessary, restart DMA at NDBP. Otherwise, if DMA
* is active, we can only safely reclaim up to CBP.
*
* For now, we'll only reclaim on inactive DMA and assume
* that a sufficiently large ring keeps us out of trouble.
*/
uint32_t reclaimto, status;
int reclaimall, i = sc->sc_prevtx;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;

status = sq_hpc_read(sc, HPC1_ENETX_CTL);
if (status & HPC1_ENETX_CTL_ACTIVE) {
SQ_TRACE(SQ_TXINTR_BUSY, sc, i, status);
return;
} else
reclaimto = sq_hpc_read(sc, HPC1_ENETX_NDBP);

if (sc->sc_nfreetx == 0 && SQ_CDTXADDR(sc, i) == reclaimto)
reclaimall = 1;
else
reclaimall = 0;

while (sc->sc_nfreetx < SQ_NTXDESC) {
if (SQ_CDTXADDR(sc, i) == reclaimto && !reclaimall)
break;

SQ_CDTXSYNC(sc, i, sc->sc_txmap[i]->dm_nsegs,
BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

/* Sync the packet data, unload DMA map, free mbuf */
bus_dmamap_sync(sc->sc_dmat, sc->sc_txmap[i],
0, sc->sc_txmap[i]->dm_mapsize, BUS_DMASYNC_POSTWRITE);
bus_dmamap_unload(sc->sc_dmat, sc->sc_txmap[i]);
m_freem(sc->sc_txmbuf[i]);
sc->sc_txmbuf[i] = NULL;

if_statinc(ifp, if_opackets);
sc->sc_nfreetx++;

SQ_TRACE(SQ_DONE_DMA, sc, i, status);

i = SQ_NEXTTX(i);
}

if (sc->sc_nfreetx < SQ_NTXDESC) {
SQ_TRACE(SQ_RESTART_DMA, sc, i, status);

KASSERT(reclaimto == SQ_CDTXADDR(sc, i));

sq_hpc_write(sc, HPC1_ENETX_CFXBP, reclaimto);
sq_hpc_write(sc, HPC1_ENETX_CBP, reclaimto);

/* Kick DMA channel into life */
sq_hpc_write(sc, HPC1_ENETX_CTL, HPC1_ENETX_CTL_ACTIVE);

/*
* Set a watchdog timer in case the chip
* flakes out.
*/
ifp->if_timer = 5;
}

sc->sc_prevtx = i;
}

/*
* Reclaim used transmit descriptors and restart the transmit DMA
* engine if necessary.
*/
static void
sq_txring_hpc3(struct sq_softc *sc)
{
/*
* HPC3 tags descriptors with a bit once they've been
* transmitted. We need only free each XMITDONE'd
* descriptor, and restart the DMA engine if any
* descriptors are left over.
*/
int i;
uint32_t status = 0;
struct ifnet *ifp = &sc->sc_ethercom.ec_if;

i = sc->sc_prevtx;
while (sc->sc_nfreetx < SQ_NTXDESC) {
/*
* Check status first so we don't end up with a case of
* the buffer not being finished while the DMA channel
* has gone idle.
*/
status = sq_hpc_read(sc, HPC3_ENETX_CTL);

SQ_CDTXSYNC(sc, i, sc->sc_txmap[i]->dm_nsegs,
BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);

/* Check for used descriptor and restart DMA chain if needed */
if ((sc->sc_txdesc[i].hpc3_hdd_ctl &
HPC3_HDD_CTL_XMITDONE) == 0) {
if ((status & HPC3_ENETX_CTL_ACTIVE) == 0) {
SQ_TRACE(SQ_RESTART_DMA, sc, i, status);

sq_hpc_write(sc, HPC3_ENETX_NDBP,
SQ_CDTXADDR(sc, i));

/* Kick DMA channel into life */
sq_hpc_write(sc, HPC3_ENETX_CTL,
HPC3_ENETX_CTL_ACTIVE);

/*
* Set a watchdog timer in case the chip
* flakes out.
*/
ifp->if_timer = 5;
} else
SQ_TRACE(SQ_TXINTR_BUSY, sc, i, status);
break;
}

/* Sync the packet data, unload DMA map, free mbuf */
bus_dmamap_sync(sc->sc_dmat, sc->sc_txmap[i],
0, sc->sc_txmap[i]->dm_mapsize, BUS_DMASYNC_POSTWRITE);
bus_dmamap_unload(sc->sc_dmat, sc->sc_txmap[i]);
m_freem(sc->sc_txmbuf[i]);
sc->sc_txmbuf[i] = NULL;

if_statinc(ifp, if_opackets);
sc->sc_nfreetx++;

SQ_TRACE(SQ_DONE_DMA, sc, i, status);
i = SQ_NEXTTX(i);
}

sc->sc_prevtx = i;
}

void
sq_reset(struct sq_softc *sc)
{

/* Stop HPC dma channels */
sq_hpc_write(sc, sc->hpc_regs->enetr_ctl, 0);
sq_hpc_write(sc, sc->hpc_regs->enetx_ctl, 0);

sq_hpc_write(sc, sc->hpc_regs->enetr_reset, 3);
delay(20);
sq_hpc_write(sc, sc->hpc_regs->enetr_reset, 0);
}

/* sq_add_rxbuf: Add a receive buffer to the indicated descriptor. */
int
sq_add_rxbuf(struct sq_softc *sc, int idx)
{
int err;
struct mbuf *m;

MGETHDR(m, M_DONTWAIT, MT_DATA);
if (m == NULL)
return ENOBUFS;

MCLGET(m, M_DONTWAIT);
if ((m->m_flags & M_EXT) == 0) {
m_freem(m);
return ENOBUFS;
}

if (sc->sc_rxmbuf[idx] != NULL)
bus_dmamap_unload(sc->sc_dmat, sc->sc_rxmap[idx]);

sc->sc_rxmbuf[idx] = m;

if ((err = bus_dmamap_load(sc->sc_dmat, sc->sc_rxmap[idx],
m->m_ext.ext_buf, m->m_ext.ext_size, NULL, BUS_DMA_NOWAIT)) != 0) {
printf("%s: can't load rx DMA map %d, error = %d\n",
device_xname(sc->sc_dev), idx, err);
panic("sq_add_rxbuf"); /* XXX */
}

bus_dmamap_sync(sc->sc_dmat, sc->sc_rxmap[idx],
0, sc->sc_rxmap[idx]->dm_mapsize, BUS_DMASYNC_PREREAD);

SQ_INIT_RXDESC(sc, idx);

return 0;
}

void
sq_dump_buffer(paddr_t addr, psize_t len)
{
u_int i;
uint8_t *physaddr = (uint8_t *)MIPS_PHYS_TO_KSEG1(addr);

if (len == 0)
return;

printf("%p: ", physaddr);

for (i = 0; i < len; i++) {
printf("%02x ", *(physaddr + i) & 0xff);
if ((i % 16) == 15 && i != len - 1)
printf("\n%p: ", physaddr + i);
}

printf("\n");
}