/*      $NetBSD: cs89x0.c,v 1.56 2025/01/07 20:24:10 andvar Exp $       */

/*
 * Copyright (c) 2004 Christopher Gilbert
 * All rights reserved.
 *
 * 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 company nor the name of the author may 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 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.
 */

/*
 * Copyright 1997
 * Digital Equipment Corporation. All rights reserved.
 *
 * This software is furnished under license and may be used and
 * copied only in accordance with the following terms and conditions.
 * Subject to these conditions, you may download, copy, install,
 * use, modify and distribute this software in source and/or binary
 * form. No title or ownership is transferred hereby.
 *
 * 1) Any source code used, modified or distributed must reproduce
 *    and retain this copyright notice and list of conditions as
 *    they appear in the source file.
 *
 * 2) No right is granted to use any trade name, trademark, or logo of
 *    Digital Equipment Corporation. Neither the "Digital Equipment
 *    Corporation" name nor any trademark or logo of Digital Equipment
 *    Corporation may be used to endorse or promote products derived
 *    from this software without the prior written permission of
 *    Digital Equipment Corporation.
 *
 * 3) This software is provided "AS-IS" and any express or implied
 *    warranties, including but not limited to, any implied warranties
 *    of merchantability, fitness for a particular purpose, or
 *    non-infringement are disclaimed. In no event shall DIGITAL be
 *    liable for any damages whatsoever, and in particular, DIGITAL
 *    shall not be liable for special, indirect, consequential, or
 *    incidental damages or damages for lost profits, loss of
 *    revenue or loss of use, whether such damages arise in contract,
 *    negligence, tort, under statute, in equity, at law or otherwise,
 *    even if advised of the possibility of such damage.
 */

/*
**++
**  FACILITY
**
**     Device Driver for the Crystal CS8900 ISA Ethernet Controller.
**
**  ABSTRACT
**
**     This module provides standard ethernet access for INET protocols
**     only.
**
**  AUTHORS
**
**     Peter Dettori     SEA - Software Engineering.
**
**  CREATION DATE:
**
**     13-Feb-1997.
**
**  MODIFICATION HISTORY (Digital):
**
**     Revision 1.27  1998/01/20  17:59:40  cgd
**     update for moved headers
**
**     Revision 1.26  1998/01/12  19:29:36  cgd
**     use arm32/isa versions of isadma code.
**
**     Revision 1.25  1997/12/12  01:35:27  cgd
**     convert to use new arp code (from Brini)
**
**     Revision 1.24  1997/12/10  22:31:56  cgd
**     trim some fat (get rid of ability to explicitly supply enet addr, since
**     it was never used and added a bunch of code which really doesn't belong in
**     an enet driver), and clean up slightly.
**
**     Revision 1.23  1997/10/06  16:42:12  cgd
**     copyright notices
**
**     Revision 1.22  1997/06/20  19:38:01  chaiken
**     fixes some smartcard problems
**
**     Revision 1.21  1997/06/10 02:56:20  grohn
**     Added call to ledNetActive
**
**     Revision 1.20  1997/06/05 00:47:06  dettori
**     Changed cs_process_rx_dma to reset and re-initialise the
**     ethernet chip when DMA gets out of sync, or mbufs
**     can't be allocated.
**
**     Revision 1.19  1997/06/03 03:09:58  dettori
**     Turn off sc_txbusy flag when a transmit underrun
**     occurs.
**
**     Revision 1.18  1997/06/02 00:04:35  dettori
**     redefined the transmit table to get around the nfs_timer bug while we are
**     looking into it further.
**
**     Also changed interrupts from EDGE to LEVEL.
**
**     Revision 1.17  1997/05/27 23:31:01  dettori
**     Pulled out changes to DMAMODE defines.
**
**     Revision 1.16  1997/05/23 04:25:16  cgd
**     reformat log so it fits in 80cols
**
**     Revision 1.15  1997/05/23  04:22:18  cgd
**     remove the existing copyright notice (which Peter Dettori indicated
**     was incorrect, copied from an existing NetBSD file only so that the
**     file would have a copyright notice on it, and which he'd intended to
**     replace).  Replace it with a Digital copyright notice, cloned from
**     ess.c.  It's not really correct either (it indicates that the source
**     is Digital confidential!), but is better than nothing and more
**     correct than what was there before.
**
**     Revision 1.14  1997/05/23  04:12:50  cgd
**     use an adaptive transmit start algorithm: start by telling the chip
**     to start transmitting after 381 bytes have been fed to it.  if that
**     gets transmit underruns, ramp down to 1021 bytes then "whole
**     packet."  If successful at a given level for a while, try the next
**     more aggressive level.  This code doesn't ever try to start
**     transmitting after 5 bytes have been sent to the NIC, because
**     that underruns rather regularly.  The back-off and ramp-up mechanism
**     could probably be tuned a little bit, but this works well enough to
**     support > 1MB/s transmit rates on a clear ethernet (which is about
**     20-25% better than the driver had previously been getting).
**
**     Revision 1.13  1997/05/22  21:06:54  cgd
**     redo cs_copy_tx_frame() from scratch.  It had a fatal flaw: it was blindly
**     casting from uint8_t * to uint16_t * without worrying about alignment
**     issues.  This would cause bogus data to be spit out for mbufs with
**     misaligned data.  For instance, it caused the following bits to appear
**     on the wire:
**      ... etBND 1S2C .SHA(K) R ...
**          11112222333344445555
**     which should have appeared as:
**      ... NetBSD 1.2C (SHARK) ...
**          11112222333344445555
**     Note the apparent 'rotate' of the bytes in the word, which was due to
**     incorrect unaligned accesses.  This data corruption was the cause of
**     incoming telnet/rlogin hangs.
**
**     Revision 1.12  1997/05/22  01:55:32  cgd
**     reformat log so it fits in 80cols
**
**     Revision 1.11  1997/05/22  01:50:27  cgd
**     * enable input packet address checking in the BPF+IFF_PROMISCUOUS case,
**       so packets aimed at other hosts don't get sent to ether_input().
**     * Add a static const char *rcsid initialized with an RCS Id tag, so that
**       you can easily tell (`strings`) what version of the driver is in your
**       kernel binary.
**     * get rid of ether_cmp().  It was inconsistently used, not necessarily
**       safe, and not really a performance win anyway.  (It was only used when
**       setting up the multicast logical address filter, which is an
**       infrequent event.  It could have been used in the IFF_PROMISCUOUS
**       address check above, but the benefit of it vs. memcmp would be
**       inconsequential, there.)  Use memcmp() instead.
**     * restructure csStartOutput to avoid the following bugs in the case where
**       txWait was being set:
**         * it would accidentally drop the outgoing packet if told to wait
**           but the outgoing packet queue was empty.
**         * it would bpf_mtap() the outgoing packet multiple times (once for
**           each time it was told to wait), and would also recalculate
**           the length of the outgoing packet each time it was told to
**           wait.
**       While there, rename txWait to txLoop, since with the new structure of
**       the code, the latter name makes more sense.
**
**     Revision 1.10  1997/05/19  02:03:20  cgd
**     Set RX_CTL in cs_set_ladr_filt(), rather than cs_initChip().  cs_initChip()
**     is the only caller of cs_set_ladr_filt(), and always calls it, so this
**     ends up being logically the same.  In cs_set_ladr_filt(), if IFF_PROMISC
**     is set, enable promiscuous mode (and set IFF_ALLMULTI), otherwise behave
**     as before.
**
**     Revision 1.9  1997/05/19  01:45:37  cgd
**     create a new function, cs_ether_input(), which does received-packet
**     BPF and ether_input processing.  This code used to be in three places,
**     and centralizing it will make adding IFF_PROMISC support much easier.
**     Also, in cs_copy_tx_frame(), put it some (currently disabled) code to
**     do copies with bus_space_write_region_2().  It's more correct, and
**     potentially more efficient.  That function needs to be gutted (to
**     deal properly with alignment issues, which it currently does wrong),
**     however, and the change doesn't gain much, so there's no point in
**     enabling it now.
**
**     Revision 1.8  1997/05/19  01:17:10  cgd
**     fix a comment re: the setting of the TxConfig register.  Clean up
**     interface counter maintenance (make it use standard idiom).
**
**--
*/

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: cs89x0.c,v 1.56 2025/01/07 20:24:10 andvar Exp $");

#include "opt_inet.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/mbuf.h>
#include <sys/syslog.h>
#include <sys/socket.h>
#include <sys/device.h>
#include <sys/malloc.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/bus.h>
#include <sys/intr.h>
#include <sys/rndsource.h>

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

#ifdef INET
#include <netinet/in.h>
#include <netinet/if_inarp.h>
#endif

#include <dev/ic/cs89x0reg.h>
#include <dev/ic/cs89x0var.h>

#ifdef SHARK
#include <shark/shark/sequoia.h>
#endif

/*
 * MACRO DEFINITIONS
 */
#define CS_OUTPUT_LOOP_MAX 100  /* max times round notorious tx loop */

/*
 * FUNCTION PROTOTYPES
 */
static void     cs_get_default_media(struct cs_softc *);
static int      cs_get_params(struct cs_softc *);
static int      cs_get_enaddr(struct cs_softc *);
static int      cs_reset_chip(struct cs_softc *);
static void     cs_reset(struct cs_softc *);
static int      cs_ioctl(struct ifnet *, u_long, void *);
static void     cs_initChip(struct cs_softc *);
static void     cs_buffer_event(struct cs_softc *, uint16_t);
static void     cs_transmit_event(struct cs_softc *, uint16_t);
static void     cs_receive_event(struct cs_softc *, uint16_t);
static void     cs_process_receive(struct cs_softc *);
static void     cs_process_rx_early(struct cs_softc *);
static void     cs_start_output(struct ifnet *);
static void     cs_copy_tx_frame(struct cs_softc *, struct mbuf *);
static void     cs_set_ladr_filt(struct cs_softc *, struct ethercom *);
static uint16_t cs_hash_index(char *);
static void     cs_counter_event(struct cs_softc *, uint16_t);

static int      cs_mediachange(struct ifnet *);
static void     cs_mediastatus(struct ifnet *, struct ifmediareq *);

static bool cs_shutdown(device_t, int);
static int cs_enable(struct cs_softc *);
static void cs_disable(struct cs_softc *);
static void cs_stop(struct ifnet *, int);
static int cs_scan_eeprom(struct cs_softc *);
static int cs_read_pktpg_from_eeprom(struct cs_softc *, int, uint16_t *);


/*
 * GLOBAL DECLARATIONS
 */

/*
 * Xmit-early table.
 *
 * To get better performance, we tell the chip to start packet
 * transmission before the whole packet is copied to the chip.
 * However, this can fail under load.  When it fails, we back off
 * to a safer setting for a little while.
 *
 * txcmd is the value of txcmd used to indicate when to start transmission.
 * better is the next 'better' state in the table.
 * better_count is the number of output packets before transition to the
 *   better state.
 * worse is the next 'worse' state in the table.
 *
 * Transition to the next worse state happens automatically when a
 * transmission underrun occurs.
 */
struct cs_xmit_early {
        uint16_t        txcmd;
        int             better;
        int             better_count;
        int             worse;
} cs_xmit_early_table[3] = {
        { TX_CMD_START_381,     0,      INT_MAX,        1, },
        { TX_CMD_START_1021,    0,      50000,          2, },
        { TX_CMD_START_ALL,     1,      5000,           2, },
};

int cs_default_media[] = {
        IFM_ETHER | IFM_10_2,
        IFM_ETHER | IFM_10_5,
        IFM_ETHER | IFM_10_T,
        IFM_ETHER | IFM_10_T | IFM_FDX,
};
int cs_default_nmedia = __arraycount(cs_default_media);

int
cs_attach(struct cs_softc *sc, uint8_t *enaddr, int *media,
          int nmedia, int defmedia)
{
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;
        const char *chipname, *medname;
        uint16_t reg;
        int i;

        /* Start out in IO mode */
        sc->sc_memorymode = FALSE;

        /* Make sure we're right */
        for (i = 0; i < 10000; i++) {
                reg = CS_READ_PACKET_PAGE(sc, PKTPG_EISA_NUM);
                if (reg == EISA_NUM_CRYSTAL)
                        break;
        }
        if (i == 10000) {
                aprint_error_dev(sc->sc_dev, "wrong id(0x%x)\n", reg);
                return 1; /* XXX should panic? */
        }

        reg = CS_READ_PACKET_PAGE(sc, PKTPG_PRODUCT_ID);
        sc->sc_prodid = reg & PROD_ID_MASK;
        sc->sc_prodrev = (reg & PROD_REV_MASK) >> 8;

        switch (sc->sc_prodid) {
        case PROD_ID_CS8900:
                chipname = "CS8900";
                break;
        case PROD_ID_CS8920:
                chipname = "CS8920";
                break;
        case PROD_ID_CS8920M:
                chipname = "CS8920M";
                break;
        default:
                panic("cs_attach: impossible");
        }

        /*
         * The first thing to do is check that the mbuf cluster size is
         * greater than the MTU for an ethernet frame. The code depends on
         * this and to port this to a OS where this was not the case would
         * not be straightforward.
         *
         * We need 1 byte spare because our packet read loop can overrun.
         * and we may need pad bytes to align ip header.
         */
        if (MCLBYTES < ETHER_MAX_LEN + 1 + ALIGN(sizeof(struct ether_header))
            - sizeof(struct ether_header)) {
                printf("%s: MCLBYTES too small for Ethernet frame\n",
                    device_xname(sc->sc_dev));
                return 1;
        }

        /* Start out not transmitting */
        sc->sc_txbusy = FALSE;

        /* Set up early transmit threshold */
        sc->sc_xe_ent = 0;
        sc->sc_xe_togo = cs_xmit_early_table[sc->sc_xe_ent].better_count;

        /* Initialize ifnet structure. */
        strlcpy(ifp->if_xname, device_xname(sc->sc_dev), IFNAMSIZ);
        ifp->if_softc = sc;
        ifp->if_start = cs_start_output;
        ifp->if_init = cs_init;
        ifp->if_ioctl = cs_ioctl;
        ifp->if_stop = cs_stop;
        ifp->if_watchdog = NULL;        /* No watchdog at this stage */
        ifp->if_flags = IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST;
        IFQ_SET_READY(&ifp->if_snd);

        /* Initialize ifmedia structures. */
        sc->sc_ethercom.ec_ifmedia = &sc->sc_media;
        ifmedia_init(&sc->sc_media, 0, cs_mediachange, cs_mediastatus);

        if (media != NULL) {
                for (i = 0; i < nmedia; i++)
                        ifmedia_add(&sc->sc_media, media[i], 0, NULL);
                ifmedia_set(&sc->sc_media, defmedia);
        } else {
                for (i = 0; i < cs_default_nmedia; i++)
                        ifmedia_add(&sc->sc_media, cs_default_media[i],
                            0, NULL);
                cs_get_default_media(sc);
        }

        if (sc->sc_cfgflags & CFGFLG_PARSE_EEPROM) {
                if (cs_scan_eeprom(sc) == CS_ERROR) {
                        /*
                         * Failed to scan the eeprom, pretend there isn't an
                         * eeprom
                         */
                        aprint_error_dev(sc->sc_dev,
                            "unable to scan EEPROM\n");
                        sc->sc_cfgflags |= CFGFLG_NOT_EEPROM;
                }
        }

        if ((sc->sc_cfgflags & CFGFLG_NOT_EEPROM) == 0) {
                /* Get parameters from the EEPROM */
                if (cs_get_params(sc) == CS_ERROR) {
                        aprint_error_dev(sc->sc_dev,
                            "unable to get settings from EEPROM\n");
                        return 1;
                }
        }

        if (enaddr != NULL)
                memcpy(sc->sc_enaddr, enaddr, sizeof(sc->sc_enaddr));
        else if ((sc->sc_cfgflags & CFGFLG_NOT_EEPROM) == 0) {
                /* Get and store the Ethernet address */
                if (cs_get_enaddr(sc) == CS_ERROR) {
                        aprint_error_dev(sc->sc_dev,
                            "unable to read Ethernet address\n");
                        return 1;
                }
        } else {
#if 1
                int j;
                uint v;

                for (j = 0; j < 6; j += 2) {
                        v = CS_READ_PACKET_PAGE(sc, PKTPG_IND_ADDR + j);
                        sc->sc_enaddr[j + 0] = v;
                        sc->sc_enaddr[j + 1] = v >> 8;
                }
#else
                printf("%s: no Ethernet address!\n", device_xname(sc->sc_dev));
                return 1;
#endif
        }

        switch (IFM_SUBTYPE(sc->sc_media.ifm_cur->ifm_media)) {
        case IFM_10_2:
                medname = "BNC";
                break;
        case IFM_10_5:
                medname = "AUI";
                break;
        case IFM_10_T:
                if (sc->sc_media.ifm_cur->ifm_media & IFM_FDX)
                        medname = "UTP <full-duplex>";
                else
                        medname = "UTP";
                break;
        default:
                panic("cs_attach: impossible");
        }
        printf("%s: %s rev. %c, address %s, media %s\n",
            device_xname(sc->sc_dev),
            chipname, sc->sc_prodrev + 'A', ether_sprintf(sc->sc_enaddr),
            medname);

        if (sc->sc_dma_attach)
                (*sc->sc_dma_attach)(sc);

        /* Attach the interface. */
        if_attach(ifp);
        if_deferred_start_init(ifp, NULL);
        ether_ifattach(ifp, sc->sc_enaddr);

        rnd_attach_source(&sc->rnd_source, device_xname(sc->sc_dev),
                          RND_TYPE_NET, RND_FLAG_DEFAULT);
        sc->sc_cfgflags |= CFGFLG_ATTACHED;

        if (pmf_device_register1(sc->sc_dev, NULL, NULL, cs_shutdown))
                pmf_class_network_register(sc->sc_dev, ifp);
        else
                aprint_error_dev(sc->sc_dev,
                    "couldn't establish power handler\n");

        /* Reset the chip */
        if (cs_reset_chip(sc) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev, "reset failed\n");
                cs_detach(sc);
                return 1;
        }

        return 0;
}

int
cs_detach(struct cs_softc *sc)
{
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;

        if (sc->sc_cfgflags & CFGFLG_ATTACHED) {
                rnd_detach_source(&sc->rnd_source);
                ether_ifdetach(ifp);
                if_detach(ifp);
                ifmedia_fini(&sc->sc_media);
                sc->sc_cfgflags &= ~CFGFLG_ATTACHED;
        }

#if 0
        /* XXX not necessary */
        if (sc->sc_cfgflags & CFGFLG_DMA_MODE) {
                isa_dmamem_unmap(sc->sc_ic, sc->sc_drq, sc->sc_dmabase,
                    sc->sc_dmasize);
                isa_dmamem_free(sc->sc_ic, sc->sc_drq, sc->sc_dmaaddr,
                    sc->sc_dmasize);
                isa_dmamap_destroy(sc->sc_ic, sc->sc_drq);
                sc->sc_cfgflags &= ~CFGFLG_DMA_MODE;
        }
#endif

        pmf_device_deregister(sc->sc_dev);

        return 0;
}

bool
cs_shutdown(device_t self, int howto)
{
        struct cs_softc *sc;

        sc = device_private(self);
        cs_reset(sc);

        return true;
}

void
cs_get_default_media(struct cs_softc *sc)
{
        uint16_t adp_cfg, xmit_ctl;

        if (cs_verify_eeprom(sc) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "cs_get_default_media: EEPROM missing or bad\n");
                goto fakeit;
        }

        if (cs_read_eeprom(sc, EEPROM_ADPTR_CFG, &adp_cfg) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "unable to read adapter config from EEPROM\n");
                goto fakeit;
        }

        if (cs_read_eeprom(sc, EEPROM_XMIT_CTL, &xmit_ctl) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "unable to read transmit control from EEPROM\n");
                goto fakeit;
        }

        switch (adp_cfg & ADPTR_CFG_MEDIA) {
        case ADPTR_CFG_AUI:
                ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_10_5);
                break;
        case ADPTR_CFG_10BASE2:
                ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_10_2);
                break;
        case ADPTR_CFG_10BASET:
        default:
                if (xmit_ctl & XMIT_CTL_FDX)
                        ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_10_T
                            | IFM_FDX);
                else
                        ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_10_T);
                break;
        }
        return;

 fakeit:
        aprint_error_dev(sc->sc_dev,
            "WARNING: default media setting may be inaccurate\n");
        /* XXX Arbitrary... */
        ifmedia_set(&sc->sc_media, IFM_ETHER | IFM_10_T);
}

/*
 * cs_scan_eeprom
 *
 * Attempt to take a complete copy of the eeprom into main memory.
 * this will allow faster parsing of the eeprom data.
 *
 * Only tested against a 8920M's eeprom, but the data sheet for the
 * 8920A indicates that is uses the same layout.
 */
int
cs_scan_eeprom(struct cs_softc *sc)
{
        uint16_t result;
        int     i;
        int     eeprom_size;
        uint8_t checksum = 0;

        if (cs_verify_eeprom(sc) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "cs_scan_params: EEPROM missing or bad\n");
                return CS_ERROR;
        }

        /*
         * Read the 0th word from the eeprom, it will tell us the length
         * and if the eeprom is valid
         */
        cs_read_eeprom(sc, 0, &result);

        /* Check the eeprom signature */
        if ((result & 0xE000) != 0xA000) {
                /* Empty eeprom */
                return CS_ERROR;
        }

        /*
         * Take the eeprom size (note the read value doesn't include the header
         * word)
         */
        eeprom_size = (result & 0xff) + 2;

        sc->eeprom_data = malloc(eeprom_size, M_DEVBUF, M_WAITOK);
        if (sc->eeprom_data == NULL) {
                /* No memory, treat this as if there's no eeprom */
                return CS_ERROR;
        }

        sc->eeprom_size = eeprom_size;

        /* Read the eeprom into the buffer, also calculate the checksum  */
        for (i = 0; i < (eeprom_size >> 1); i++) {
                cs_read_eeprom(sc, i, &(sc->eeprom_data[i]));
                checksum += (sc->eeprom_data[i] & 0xff00) >> 8;
                checksum += (sc->eeprom_data[i] & 0x00ff);
        }

        /*
         * Validate checksum calculation, the sum of all the bytes should be 0,
         * as the high byte of the last word is the 2's complement of the
         * sum to that point.
         */
        if (checksum != 0) {
                aprint_error_dev(sc->sc_dev, "eeprom checksum failure\n");
                return CS_ERROR;
        }

        return CS_OK;
}

static int
cs_read_pktpg_from_eeprom(struct cs_softc *sc, int pktpg, uint16_t *pValue)
{
        int x, maxword;

        /* Check that we have eeprom data */
        if ((sc->eeprom_data == NULL) || (sc->eeprom_size < 2))
                return CS_ERROR;

        /*
         * We only want to read the data words, the last word contains the
         * checksum
         */
        maxword = (sc->eeprom_size - 2) >> 1;

        /* Start 1 word in, as the first word is the length and signature */
        x = 1;

        while ( x < (maxword)) {
                uint16_t header;
                int group_size;
                int offset;
                int offset_max;

                /* Read in the group header word */
                header = sc->eeprom_data[x];
                x++;    /* Skip group header */

                /*
                 * Size of group in words is in the top 4 bits, note that it
                 * is one less than the number of words
                 */
                group_size = header & 0xF000;

                /*
                 * CS8900 Data sheet says this should be 0x01ff,
                 * but my cs8920 eeprom has higher offsets,
                 * perhaps the 8920 allows higher offsets, otherwise
                 * it's writing to places that it shouldn't
                 */
                /* Work out the offsets this group covers */
                offset = header & 0x0FFF;
                offset_max = offset + (group_size << 1);

                /* Check if the pkgpg we're after is in this group */
                if ((offset <= pktpg) && (pktpg <= offset_max)) {
                        /* The pkgpg value we want is in here */
                        int eeprom_location;

                        eeprom_location = ((pktpg - offset) >> 1) ;

                        *pValue = sc->eeprom_data[x + eeprom_location];
                        return CS_OK;
                } else {
                        /* Skip this group (+ 1 for first entry) */
                        x += group_size + 1;
                }
        }

        /*
         * If we've fallen out here then we don't have a value in the EEPROM
         * for this pktpg so return an error
         */
        return CS_ERROR;
}

int
cs_get_params(struct cs_softc *sc)
{
        uint16_t isaConfig;
        uint16_t adapterConfig;

        if (cs_verify_eeprom(sc) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "cs_get_params: EEPROM missing or bad\n");
                return CS_ERROR;
        }

        if (sc->sc_cfgflags & CFGFLG_PARSE_EEPROM) {
                /* Get ISA configuration from the EEPROM */
                if (cs_read_pktpg_from_eeprom(sc, PKTPG_BUS_CTL, &isaConfig)
                    == CS_ERROR) {
                        /*
                         * Eeprom doesn't have this value, use data sheet
                         * default
                         */
                        isaConfig = 0x0017;
                }

                /* Get adapter configuration from the EEPROM */
                if (cs_read_pktpg_from_eeprom(sc, PKTPG_SELF_CTL,
                    &adapterConfig) == CS_ERROR) {
                        /*
                         * Eeprom doesn't have this value, use data sheet
                         * default
                         */
                        adapterConfig = 0x0015;
                }

                /* Copy the USE_SA flag */
                if (isaConfig & BUS_CTL_USE_SA)
                        sc->sc_cfgflags |= CFGFLG_USE_SA;

                /* Copy the IO Channel Ready flag */
                if (isaConfig & BUS_CTL_IOCHRDY)
                        sc->sc_cfgflags |= CFGFLG_IOCHRDY;

                /* Copy the DC/DC Polarity flag */
                if (adapterConfig & SELF_CTL_HCB1)
                        sc->sc_cfgflags |= CFGFLG_DCDC_POL;
        } else {
                /* Get ISA configuration from the EEPROM */
                if (cs_read_eeprom(sc, EEPROM_ISA_CFG, &isaConfig) == CS_ERROR)
                        goto eeprom_bad;

                /* Get adapter configuration from the EEPROM */
                if (cs_read_eeprom(sc, EEPROM_ADPTR_CFG, &adapterConfig)
                    == CS_ERROR)
                        goto eeprom_bad;

                /* Copy the USE_SA flag */
                if (isaConfig & ISA_CFG_USE_SA)
                        sc->sc_cfgflags |= CFGFLG_USE_SA;

                /* Copy the IO Channel Ready flag */
                if (isaConfig & ISA_CFG_IOCHRDY)
                        sc->sc_cfgflags |= CFGFLG_IOCHRDY;

                /* Copy the DC/DC Polarity flag */
                if (adapterConfig & ADPTR_CFG_DCDC_POL)
                        sc->sc_cfgflags |= CFGFLG_DCDC_POL;
        }

        return CS_OK;
eeprom_bad:
        aprint_error_dev(sc->sc_dev,
            "cs_get_params: unable to read from EEPROM\n");
        return CS_ERROR;
}

int
cs_get_enaddr(struct cs_softc *sc)
{
        uint16_t myea[ETHER_ADDR_LEN / sizeof(uint16_t)];
        int i;

        if (cs_verify_eeprom(sc) == CS_ERROR) {
                aprint_error_dev(sc->sc_dev,
                    "cs_get_enaddr: EEPROM missing or bad\n");
                return CS_ERROR;
        }

        /* Get Ethernet address from the EEPROM */
        if (sc->sc_cfgflags & CFGFLG_PARSE_EEPROM) {
                if (cs_read_pktpg_from_eeprom(sc, PKTPG_IND_ADDR, &myea[0])
                                == CS_ERROR)
                        goto eeprom_bad;
                if (cs_read_pktpg_from_eeprom(sc, PKTPG_IND_ADDR + 2, &myea[1])
                                == CS_ERROR)
                        goto eeprom_bad;
                if (cs_read_pktpg_from_eeprom(sc, PKTPG_IND_ADDR + 4, &myea[2])
                                == CS_ERROR)
                        goto eeprom_bad;
        } else {
                if (cs_read_eeprom(sc, EEPROM_IND_ADDR_H, &myea[0]) == CS_ERROR)
                        goto eeprom_bad;
                if (cs_read_eeprom(sc, EEPROM_IND_ADDR_M, &myea[1]) == CS_ERROR)
                        goto eeprom_bad;
                if (cs_read_eeprom(sc, EEPROM_IND_ADDR_L, &myea[2]) == CS_ERROR)
                        goto eeprom_bad;
        }

        for (i = 0; i < __arraycount(myea); i++) {
                sc->sc_enaddr[i * 2 + 0] = myea[i];
                sc->sc_enaddr[i * 2 + 1] = myea[i] >> 8;
        }

        return CS_OK;

 eeprom_bad:
        aprint_error_dev(sc->sc_dev,
            "cs_get_enaddr: unable to read from EEPROM\n");
        return CS_ERROR;
}

int
cs_reset_chip(struct cs_softc *sc)
{
        int intState;
        int x;

        /* Disable interrupts at the CPU so reset command is atomic */
        intState = splnet();

        /*
         * We are now resetting the chip
         *
         * A spurious interrupt is generated by the chip when it is reset. This
         * variable informs the interrupt handler to ignore this interrupt.
         */
        sc->sc_resetting = TRUE;

        /* Issue a reset command to the chip */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_SELF_CTL, SELF_CTL_RESET);

        /* Re-enable interrupts at the CPU */
        splx(intState);

        /* The chip is always in IO mode after a reset */
        sc->sc_memorymode = FALSE;

        /* If transmission was in progress, it is not now */
        sc->sc_txbusy = FALSE;

        /*
         * There was a delay(125); here, but it seems unnecessary 125 usec is
         * 1/8000 of a second, not 1/8 of a second. the data sheet advises
         * 1/10 of a second here, but the SI_BUSY and INIT_DONE loops below
         * should be sufficient.
         */

        /* Transition SBHE to switch chip from 8-bit to 16-bit */
        IO_READ_1(sc, PORT_PKTPG_PTR + 0);
        IO_READ_1(sc, PORT_PKTPG_PTR + 1);
        IO_READ_1(sc, PORT_PKTPG_PTR + 0);
        IO_READ_1(sc, PORT_PKTPG_PTR + 1);

        /* Wait until the EEPROM is not busy */
        for (x = 0; x < MAXLOOP; x++) {
                if (!(CS_READ_PACKET_PAGE(sc, PKTPG_SELF_ST) & SELF_ST_SI_BUSY))
                        break;
        }

        if (x == MAXLOOP)
                return CS_ERROR;

        /* Wait until initialization is done */
        for (x = 0; x < MAXLOOP; x++) {
                if (CS_READ_PACKET_PAGE(sc, PKTPG_SELF_ST) & SELF_ST_INIT_DONE)
                        break;
        }

        if (x == MAXLOOP)
                return CS_ERROR;

        /* Reset is no longer in progress */
        sc->sc_resetting = FALSE;

        return CS_OK;
}

int
cs_verify_eeprom(struct cs_softc *sc)
{
        uint16_t self_status;

        /* Verify that the EEPROM is present and OK */
        self_status = CS_READ_PACKET_PAGE_IO(sc, PKTPG_SELF_ST);
        if (((self_status & SELF_ST_EEP_PRES) &&
             (self_status & SELF_ST_EEP_OK)) == 0)
                return CS_ERROR;

        return CS_OK;
}

int
cs_read_eeprom(struct cs_softc *sc, int offset, uint16_t *pValue)
{
        int x;

        /* Ensure that the EEPROM is not busy */
        for (x = 0; x < MAXLOOP; x++) {
                if (!(CS_READ_PACKET_PAGE_IO(sc, PKTPG_SELF_ST) &
                      SELF_ST_SI_BUSY))
                        break;
        }

        if (x == MAXLOOP)
                return CS_ERROR;

        /* Issue the command to read the offset within the EEPROM */
        CS_WRITE_PACKET_PAGE_IO(sc, PKTPG_EEPROM_CMD,
            offset | EEPROM_CMD_READ);

        /* Wait until the command is completed */
        for (x = 0; x < MAXLOOP; x++) {
                if (!(CS_READ_PACKET_PAGE_IO(sc, PKTPG_SELF_ST) &
                      SELF_ST_SI_BUSY))
                        break;
        }

        if (x == MAXLOOP)
                return CS_ERROR;

        /* Get the EEPROM data from the EEPROM Data register */
        *pValue = CS_READ_PACKET_PAGE_IO(sc, PKTPG_EEPROM_DATA);

        return CS_OK;
}

void
cs_initChip(struct cs_softc *sc)
{
        uint16_t busCtl;
        uint16_t selfCtl;
        uint16_t v;
        uint16_t isaId;
        int i;
        int media = IFM_SUBTYPE(sc->sc_media.ifm_cur->ifm_media);

        /* Disable reception and transmission of frames */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LINE_CTL,
            CS_READ_PACKET_PAGE(sc, PKTPG_LINE_CTL) &
            ~LINE_CTL_RX_ON & ~LINE_CTL_TX_ON);

        /* Disable interrupt at the chip */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
            CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL) & ~BUS_CTL_INT_ENBL);

        /* If IOCHRDY is enabled then clear the bit in the busCtl register */
        busCtl = CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL);
        if (sc->sc_cfgflags & CFGFLG_IOCHRDY) {
                CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
                    busCtl & ~BUS_CTL_IOCHRDY);
        } else {
                CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
                    busCtl | BUS_CTL_IOCHRDY);
        }

        /* Set the Line Control register to match the media type */
        if (media == IFM_10_T)
                CS_WRITE_PACKET_PAGE(sc, PKTPG_LINE_CTL, LINE_CTL_10BASET);
        else
                CS_WRITE_PACKET_PAGE(sc, PKTPG_LINE_CTL, LINE_CTL_AUI_ONLY);

        /*
         * Set the BSTATUS/HC1 pin to be used as HC1.  HC1 is used to
         * enable the DC/DC converter
         */
        selfCtl = SELF_CTL_HC1E;

        /* If the media type is 10Base2 */
        if (media == IFM_10_2) {
                /* Enable the DC/DC converter if it has a low enable. */
                if ((sc->sc_cfgflags & CFGFLG_DCDC_POL) == 0)
                        /*
                         * Set the HCB1 bit, which causes the HC1 pin to go
                         * low.
                         */
                        selfCtl |= SELF_CTL_HCB1;
        } else { /* Media type is 10BaseT or AUI */
                /* Disable the DC/DC converter if it has a high enable. */
                if ((sc->sc_cfgflags & CFGFLG_DCDC_POL) != 0) {
                        /*
                         * Set the HCB1 bit, which causes the HC1 pin to go
                         * low.
                         */
                        selfCtl |= SELF_CTL_HCB1;
                }
        }
        CS_WRITE_PACKET_PAGE(sc, PKTPG_SELF_CTL, selfCtl);

        /* Enable normal link pulse */
        if (sc->sc_prodid == PROD_ID_CS8920 || sc->sc_prodid == PROD_ID_CS8920M)
                CS_WRITE_PACKET_PAGE(sc, PKTPG_AUTONEG_CTL, AUTOCTL_NLP_ENABLE);

        /* Enable full-duplex, if appropriate */
        if (sc->sc_media.ifm_cur->ifm_media & IFM_FDX)
                CS_WRITE_PACKET_PAGE(sc, PKTPG_TEST_CTL, TEST_CTL_FDX);

        /* RX_CTL set in cs_set_ladr_filt(), below */

        /* Enable all transmission interrupts */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_TX_CFG, TX_CFG_ALL_IE);

        /* Accept all receive interrupts */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG, RX_CFG_ALL_IE);

        /*
         * Configure Operational Modes
         *
         * I have turned off the BUF_CFG_RX_MISS_IE, to speed things up, this
         * is a better way to do it because the card has a counter which can be
         * read to update the RX_MISS counter. This saves many interrupts.
         *
         * I have turned on the tx and rx overflow interrupts to counter using
         * the receive miss interrupt. This is a better estimate of errors
         * and requires lower system overhead.
         */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_BUF_CFG, BUF_CFG_TX_UNDR_IE |
                          BUF_CFG_RX_DMA_IE);

        if (sc->sc_dma_chipinit)
                (*sc->sc_dma_chipinit)(sc);

        /* If memory mode is enabled */
        if (sc->sc_cfgflags & CFGFLG_MEM_MODE) {
                /* If external logic is present for address decoding */
                if (CS_READ_PACKET_PAGE(sc, PKTPG_SELF_ST) & SELF_ST_EL_PRES) {
                        /*
                         * Program the external logic to decode address bits
                         * SA20-SA23
                         */
                        CS_WRITE_PACKET_PAGE(sc, PKTPG_EEPROM_CMD,
                            ((sc->sc_pktpgaddr & 0xffffff) >> 20) |
                            EEPROM_CMD_ELSEL);
                }

                /*
                 * Write the packet page base physical address to the memory
                 * base register.
                 */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_MEM_BASE + 0,
                    sc->sc_pktpgaddr & 0xFFFF);
                CS_WRITE_PACKET_PAGE(sc, PKTPG_MEM_BASE + 2,
                    sc->sc_pktpgaddr >> 16);
                busCtl = BUS_CTL_MEM_MODE;

                /* Tell the chip to read the addresses off the SA pins */
                if (sc->sc_cfgflags & CFGFLG_USE_SA) {
                        busCtl |= BUS_CTL_USE_SA;
                }
                CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
                    CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL) | busCtl);

                /* We are in memory mode now! */
                sc->sc_memorymode = TRUE;

                /*
                 * Wait here (10ms) for the chip to swap over. this is the
                 * maximum time that this could take.
                 */
                delay(10000);

                /* Verify that we can read from the chip */
                isaId = CS_READ_PACKET_PAGE(sc, PKTPG_EISA_NUM);

                /*
                 * As a last minute sanity check before actually using mapped
                 * memory we verify that we can read the isa number from the
                 * chip in memory mode.
                 */
                if (isaId != EISA_NUM_CRYSTAL) {
                        aprint_error_dev(sc->sc_dev,
                            "failed to enable memory mode\n");
                        sc->sc_memorymode = FALSE;
                } else {
                        /*
                         * We are in memory mode so if we aren't using DMA,
                         * then program the chip to interrupt early.
                         */
                        if ((sc->sc_cfgflags & CFGFLG_DMA_MODE) == 0) {
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_BUF_CFG,
                                    BUF_CFG_RX_DEST_IE |
                                    BUF_CFG_RX_MISS_OVER_IE |
                                    BUF_CFG_TX_COL_OVER_IE);
                        }
                }

        }

        /* Put Ethernet address into the Individual Address register */
        for (i = 0; i < 6; i += 2) {
                v = sc->sc_enaddr[i + 0] | (sc->sc_enaddr[i + 1]) << 8;
                CS_WRITE_PACKET_PAGE(sc, PKTPG_IND_ADDR + i, v);
        }

        if (sc->sc_irq != -1) {
                /* Set the interrupt level in the chip */
                if (sc->sc_prodid == PROD_ID_CS8900) {
                        if (sc->sc_irq == 5)
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_INT_NUM, 3);
                        else
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_INT_NUM,
                                    (sc->sc_irq) - 10);
                } else { /* CS8920 */
                        CS_WRITE_PACKET_PAGE(sc, PKTPG_8920_INT_NUM,
                            sc->sc_irq);
                }
        }

        /* Write the multicast mask to the address filter register */
        cs_set_ladr_filt(sc, &sc->sc_ethercom);

        /* Enable reception and transmission of frames */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LINE_CTL,
            CS_READ_PACKET_PAGE(sc, PKTPG_LINE_CTL) |
            LINE_CTL_RX_ON | LINE_CTL_TX_ON);

        /* Enable interrupt at the chip */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL,
            CS_READ_PACKET_PAGE(sc, PKTPG_BUS_CTL) | BUS_CTL_INT_ENBL);
}

int
cs_init(struct ifnet *ifp)
{
        int intState;
        int error = CS_OK;
        struct cs_softc *sc = ifp->if_softc;

        if (cs_enable(sc))
                goto out;

        cs_stop(ifp, 0);

        intState = splnet();

#if 0
        /* Mark the interface as down */
        sc->sc_ethercom.ec_if.if_flags &= ~(IFF_UP | IFF_RUNNING);
#endif

#ifdef CS_DEBUG
        /* Enable debugging */
        sc->sc_ethercom.ec_if.if_flags |= IFF_DEBUG;
#endif

        /* Reset the chip */
        if ((error = cs_reset_chip(sc)) == CS_OK) {
                /* Initialize the chip */
                cs_initChip(sc);

                /* Mark the interface as running */
                sc->sc_ethercom.ec_if.if_flags |= IFF_RUNNING;
                sc->sc_ethercom.ec_if.if_timer = 0;

                /* Assume we have carrier until we are told otherwise. */
                sc->sc_carrier = 1;
        } else
                aprint_error_dev(sc->sc_dev, "unable to reset chip\n");

        splx(intState);
out:
        if (error == CS_OK)
                return 0;
        return EIO;
}

void
cs_set_ladr_filt(struct cs_softc *sc, struct ethercom *ec)
{
        struct ifnet *ifp = &ec->ec_if;
        struct ether_multi *enm;
        struct ether_multistep step;
        uint16_t af[4];
        uint16_t port, mask, index;

        /*
         * Set up multicast address filter by passing all multicast addresses
         * through a crc generator, and then using the high order 6 bits as an
         * index into the 64 bit logical address filter.  The high order bit
         * selects the word, while the rest of the bits select the bit within
         * the word.
         */
        if (ifp->if_flags & IFF_PROMISC) {
                /* Accept all valid frames. */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CTL,
                    RX_CTL_PROMISC_A | RX_CTL_RX_OK_A |
                    RX_CTL_IND_A | RX_CTL_BCAST_A | RX_CTL_MCAST_A);
                ifp->if_flags |= IFF_ALLMULTI;
                return;
        }

        /*
         * Accept frames if a. crc valid, b. individual address match c.
         * broadcast address,and d. multicast addresses matched in the hash
         * filter
         */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CTL,
            RX_CTL_RX_OK_A | RX_CTL_IND_A | RX_CTL_BCAST_A | RX_CTL_MCAST_A);


        /*
         * Start off with all multicast flag clear, set it if we need to
         * later, otherwise we will leave it.
         */
        ifp->if_flags &= ~IFF_ALLMULTI;
        af[0] = af[1] = af[2] = af[3] = 0x0000;

        /*
         * Loop through all the multicast addresses unless we get a range of
         * addresses, in which case we will just accept all packets.
         * Justification for this is given in the next comment.
         */
        ETHER_LOCK(ec);
        ETHER_FIRST_MULTI(step, ec, enm);
        while (enm != NULL) {
                if (memcmp(enm->enm_addrlo, enm->enm_addrhi,
                    sizeof enm->enm_addrlo)) {
                        /*
                         * We must listen to a range of multicast addresses.
                         * For now, just accept all multicasts, rather than
                         * trying to set only those filter bits needed to match
                         * the range.  (At this time, the only use of address
                         * ranges is for IP multicast routing, for which the
                         * range is big enough to require all bits set.)
                         */
                        ifp->if_flags |= IFF_ALLMULTI;
                        af[0] = af[1] = af[2] = af[3] = 0xffff;
                        break;
                } else {
                        /*
                         * We have got an individual address so just set that
                         * bit.
                         */
                        index = cs_hash_index(enm->enm_addrlo);

                        /* Set the bit the Logical address filter. */
                        port = (uint16_t) (index >> 4);
                        mask = (uint16_t) (1 << (index & 0xf));
                        af[port] |= mask;

                        ETHER_NEXT_MULTI(step, enm);
                }
        }
        ETHER_UNLOCK(ec);

        /* Now program the chip with the addresses */
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LOG_ADDR + 0, af[0]);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LOG_ADDR + 2, af[1]);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LOG_ADDR + 4, af[2]);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_LOG_ADDR + 6, af[3]);
        return;
}

uint16_t
cs_hash_index(char *addr)
{
        uint32_t crc;
        uint16_t hash_code;

        crc = ether_crc32_le(addr, ETHER_ADDR_LEN);

        hash_code = crc >> 26;
        return hash_code;
}

void
cs_reset(struct cs_softc *sc)
{

        /* Mark the interface as down */
        sc->sc_ethercom.ec_if.if_flags &= ~IFF_RUNNING;

        /* Reset the chip */
        cs_reset_chip(sc);
}

int
cs_ioctl(struct ifnet *ifp, u_long cmd, void *data)
{
        struct cs_softc *sc = ifp->if_softc;
        int state;
        int result;

        state = splnet();

        result = 0;             /* Only set if something goes wrong */

        switch (cmd) {
        default:
                result = ether_ioctl(ifp, cmd, data);
                if (result == ENETRESET) {
                        if (ifp->if_flags & IFF_RUNNING) {
                                /*
                                 * Multicast list has changed.  Set the
                                 * hardware filter accordingly.
                                 */
                                cs_set_ladr_filt(sc, &sc->sc_ethercom);
                        }
                        result = 0;
                }
                break;
        }

        splx(state);

        return result;
}

int
cs_mediachange(struct ifnet *ifp)
{

        /*
         * Current media is already set up.  Just reset the interface
         * to let the new value take hold.
         */
        cs_init(ifp);
        return 0;
}

void
cs_mediastatus(struct ifnet *ifp, struct ifmediareq *ifmr)
{
        struct cs_softc *sc = ifp->if_softc;

        /* The currently selected media is always the active media. */
        ifmr->ifm_active = sc->sc_media.ifm_cur->ifm_media;

        if (ifp->if_flags & IFF_UP) {
                /* Interface up, status is valid. */
                ifmr->ifm_status = IFM_AVALID |
                    (sc->sc_carrier ? IFM_ACTIVE : 0);
        }
                else ifmr->ifm_status = 0;
}

int
cs_intr(void *arg)
{
        struct cs_softc *sc = arg;
        uint16_t Event;
        uint16_t rndEvent;

/*printf("cs_intr %p\n", sc);*/
        /* Ignore any interrupts that happen while the chip is being reset */
        if (sc->sc_resetting) {
                printf("%s: cs_intr: reset in progress\n",
                    device_xname(sc->sc_dev));
                return 1;
        }

        /* Read an event from the Interrupt Status Queue */
        if (sc->sc_memorymode)
                Event = CS_READ_PACKET_PAGE(sc, PKTPG_ISQ);
        else
                Event = CS_READ_PORT(sc, PORT_ISQ);

        if ((Event & REG_NUM_MASK) == 0 || Event == 0xffff)
                return 0;       /* Not ours */

        rndEvent = Event;

        /* Process all the events in the Interrupt Status Queue */
        while ((Event & REG_NUM_MASK) != 0 && Event != 0xffff) {
                /* Dispatch to an event handler based on the register number */
                switch (Event & REG_NUM_MASK) {
                case REG_NUM_RX_EVENT:
                        cs_receive_event(sc, Event);
                        break;
                case REG_NUM_TX_EVENT:
                        cs_transmit_event(sc, Event);
                        break;
                case REG_NUM_BUF_EVENT:
                        cs_buffer_event(sc, Event);
                        break;
                case REG_NUM_TX_COL:
                case REG_NUM_RX_MISS:
                        cs_counter_event(sc, Event);
                        break;
                default:
                        printf("%s: unknown interrupt event 0x%x\n",
                            device_xname(sc->sc_dev), Event);
                        break;
                }

                /* Read another event from the Interrupt Status Queue */
                if (sc->sc_memorymode)
                        Event = CS_READ_PACKET_PAGE(sc, PKTPG_ISQ);
                else
                        Event = CS_READ_PORT(sc, PORT_ISQ);
        }

        /* have handled the interrupt */
        rnd_add_uint32(&sc->rnd_source, rndEvent);
        return 1;
}

void
cs_counter_event(struct cs_softc *sc, uint16_t cntEvent)
{
        struct ifnet *ifp;
        uint16_t errorCount;

        ifp = &sc->sc_ethercom.ec_if;

        switch (cntEvent & REG_NUM_MASK) {
        case REG_NUM_TX_COL:
                /* The count should be read before an overflow occurs. */
                errorCount = CS_READ_PACKET_PAGE(sc, PKTPG_TX_COL);
                /*
                 * The transmit event routine always checks the number of
                 * collisions for any packet so we don't increment any
                 * counters here, as they should already have been
                 * considered.
                 */
                break;
        case REG_NUM_RX_MISS:
                /* The count should be read before an overflow occurs. */
                errorCount = CS_READ_PACKET_PAGE(sc, PKTPG_RX_MISS);
                /*
                 * Increment the input error count, the first 6bits are the
                 * register id.
                 */
                if_statadd(ifp, if_ierrors, (errorCount & 0xffC0) >> 6);
                break;
        default:
                /* Do nothing */
                break;
        }
}

void
cs_buffer_event(struct cs_softc *sc, uint16_t bufEvent)
{

        /*
         * Multiple events can be in the buffer event register at one time so
         * a standard switch statement will not suffice, here every event
         * must be checked.
         */

        /*
         * If 128 bits have been rxed by the time we get here, the dest event
         * will be cleared and 128 event will be set.
         */
        if ((bufEvent & (BUF_EVENT_RX_DEST | BUF_EVENT_RX_128)) != 0)
                cs_process_rx_early(sc);

        if (bufEvent & BUF_EVENT_RX_DMA) {
                /* Process the receive data */
                if (sc->sc_dma_process_rx)
                        (*sc->sc_dma_process_rx)(sc);
                else
                        /* Should panic? */
                        aprint_error_dev(sc->sc_dev, "unexpected DMA event\n");
        }

        if (bufEvent & BUF_EVENT_TX_UNDR) {
#if 0
                /*
                 * This can happen occasionally, and it's not worth worrying
                 * about.
                 */
                printf("%s: transmit underrun (%d -> %d)\n",
                    device_xname(sc->sc_dev), sc->sc_xe_ent,
                    cs_xmit_early_table[sc->sc_xe_ent].worse);
#endif
                sc->sc_xe_ent = cs_xmit_early_table[sc->sc_xe_ent].worse;
                sc->sc_xe_togo =
                    cs_xmit_early_table[sc->sc_xe_ent].better_count;

                /* had an underrun, transmit is finished */
                sc->sc_txbusy = FALSE;
        }

        if (bufEvent & BUF_EVENT_SW_INT)
                printf("%s: software initiated interrupt\n",
                    device_xname(sc->sc_dev));
}

void
cs_transmit_event(struct cs_softc *sc, uint16_t txEvent)
{
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;

        /* If there were any errors transmitting this frame */
        if (txEvent & (TX_EVENT_LOSS_CRS | TX_EVENT_SQE_ERR |
            TX_EVENT_OUT_WIN | TX_EVENT_JABBER | TX_EVENT_16_COLL)) {
                /* Increment the output error count */
                if_statinc(ifp, if_oerrors);

                /* Note carrier loss. */
                if (txEvent & TX_EVENT_LOSS_CRS)
                        sc->sc_carrier = 0;

                /* If debugging is enabled then log error messages */
                if (ifp->if_flags & IFF_DEBUG) {
                        if (txEvent & TX_EVENT_LOSS_CRS)
                                aprint_error_dev(sc->sc_dev, "lost carrier\n");

                        if (txEvent & TX_EVENT_SQE_ERR)
                                aprint_error_dev(sc->sc_dev, "SQE error\n");

                        if (txEvent & TX_EVENT_OUT_WIN)
                                aprint_error_dev(sc->sc_dev,
                                    "out-of-window collision\n");

                        if (txEvent & TX_EVENT_JABBER)
                                aprint_error_dev(sc->sc_dev, "jabber\n");

                        if (txEvent & TX_EVENT_16_COLL)
                                aprint_error_dev(sc->sc_dev,
                                    "16 collisions\n");
                }
        } else {
                /* Transmission successful, carrier is up. */
                sc->sc_carrier = 1;
#ifdef SHARK
                ledNetActive();
#endif
        }

        /* Add the number of collisions for this frame */
        net_stat_ref_t nsr = IF_STAT_GETREF(ifp);
        if (txEvent & TX_EVENT_16_COLL)
                if_statadd_ref(ifp, nsr, if_collisions, 16);
        else
                if_statadd_ref(ifp, nsr, if_collisions,
                    ((txEvent & TX_EVENT_COLL_MASK) >> 11));

        if_statinc_ref(ifp, nsr, if_opackets);
        IF_STAT_PUTREF(ifp);

        /* Transmission is no longer in progress */
        sc->sc_txbusy = FALSE;

        /* If there is more to transmit, start the next transmission */
        if_schedule_deferred_start(ifp);
}

void
cs_print_rx_errors(struct cs_softc *sc, uint16_t rxEvent)
{

        if (rxEvent & RX_EVENT_RUNT)
                aprint_error_dev(sc->sc_dev, "runt\n");

        if (rxEvent & RX_EVENT_X_DATA)
                aprint_error_dev(sc->sc_dev, "extra data\n");

        if (rxEvent & RX_EVENT_CRC_ERR) {
                if (rxEvent & RX_EVENT_DRIBBLE)
                        aprint_error_dev(sc->sc_dev, "alignment error\n");
                else
                        aprint_error_dev(sc->sc_dev, "CRC error\n");
        } else {
                if (rxEvent & RX_EVENT_DRIBBLE)
                        aprint_error_dev(sc->sc_dev, "dribble bits\n");
        }
}

void
cs_receive_event(struct cs_softc *sc, uint16_t rxEvent)
{
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;

        /* If the frame was not received OK */
        if (!(rxEvent & RX_EVENT_RX_OK)) {
                /* Increment the input error count */
                if_statinc(ifp, if_ierrors);

                /* If debugging is enabled then log error messages. */
                if (ifp->if_flags & IFF_DEBUG) {
                        if (rxEvent != REG_NUM_RX_EVENT) {
                                cs_print_rx_errors(sc, rxEvent);

                                /*
                                 * Must read the length of all received
                                 * frames
                                 */
                                CS_READ_PACKET_PAGE(sc, PKTPG_RX_LENGTH);

                                /* Skip the received frame */
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                                        CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG) |
                                                  RX_CFG_SKIP);
                        } else
                                aprint_error_dev(sc->sc_dev, "implied skip\n");
                }
        } else {
                /*
                 * Process the received frame and pass it up to the upper
                 * layers.
                 */
                cs_process_receive(sc);
        }
}

void
cs_ether_input(struct cs_softc *sc, struct mbuf *m)
{
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;

        /* Pass the packet up. */
        if_percpuq_enqueue(ifp->if_percpuq, m);
}

void
cs_process_receive(struct cs_softc *sc)
{
        struct ifnet *ifp;
        struct mbuf *m;
        int totlen;
        uint16_t *pBuff, *pBuffLimit;
        int pad;
        unsigned int frameOffset = 0;   /* XXX: gcc */

#ifdef SHARK
        ledNetActive();
#endif

        ifp = &sc->sc_ethercom.ec_if;

        /* Received a packet; carrier is up. */
        sc->sc_carrier = 1;

        if (sc->sc_memorymode) {
                /* Initialize the frame offset */
                frameOffset = PKTPG_RX_LENGTH;

                /* Get the length of the received frame */
                totlen = CS_READ_PACKET_PAGE(sc, frameOffset);
                frameOffset += 2;
        } else {
                /* Drop status */
                CS_READ_PORT(sc, PORT_RXTX_DATA);

                /* Get the length of the received frame */
                totlen = CS_READ_PORT(sc, PORT_RXTX_DATA);
        }

        if (totlen > ETHER_MAX_LEN) {
                aprint_error_dev(sc->sc_dev, "invalid packet length %d\n",
                    totlen);

                /* Skip the received frame */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                        CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG) | RX_CFG_SKIP);
                return;
        }

        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == 0) {
                aprint_error_dev(sc->sc_dev,
                    "cs_process_receive: unable to allocate mbuf\n");
                if_statinc(ifp, if_ierrors);
                /*
                 * Couldn't allocate an mbuf so things are not good, may as
                 * well drop the packet I think.
                 *
                 * have already read the length so we should be right to skip
                 * the packet.
                 */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                    CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG) | RX_CFG_SKIP);
                return;
        }
        m_set_rcvif(m, ifp);
        m->m_pkthdr.len = totlen;

        /* Number of bytes to align ip header on word boundary for ipintr */
        pad = ALIGN(sizeof(struct ether_header)) - sizeof(struct ether_header);

        /*
         * Alloc mbuf cluster if we need.
         * We need 1 byte spare because following packet read loop can overrun.
         */
        if (totlen + pad + 1 > MHLEN) {
                MCLGET(m, M_DONTWAIT);
                if ((m->m_flags & M_EXT) == 0) {
                        /* Couldn't allocate an mbuf cluster */
                        aprint_error_dev(sc->sc_dev,
                            "cs_process_receive: "
                            "unable to allocate a cluster\n");
                        m_freem(m);

                        /* Skip the received frame */
                        CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                            CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG)
                            | RX_CFG_SKIP);
                        return;
                }
        }

        /* Align ip header on word boundary for ipintr */
        m->m_data += pad;

        m->m_len = totlen;
        pBuff = mtod(m, uint16_t *);

        /* Now read the data from the chip */
        if (sc->sc_memorymode) {
                /* Don't want to go over */
                pBuffLimit = pBuff + (totlen + 1) / 2;

                while (pBuff < pBuffLimit) {
                        *pBuff++ = CS_READ_PACKET_PAGE(sc, frameOffset);
                        frameOffset += 2;
                }
        } else
                IO_READ_MULTI_2(sc, PORT_RXTX_DATA, pBuff, (totlen + 1)>>1);

        cs_ether_input(sc, m);
}

void
cs_process_rx_early(struct cs_softc *sc)
{
        struct ifnet *ifp;
        struct mbuf *m;
        uint16_t frameCount, oldFrameCount;
        uint16_t rxEvent;
        uint16_t *pBuff;
        int pad;
        unsigned int frameOffset;


        ifp = &sc->sc_ethercom.ec_if;

        /* Initialize the frame offset */
        frameOffset = PKTPG_RX_FRAME;
        frameCount = 0;

        MGETHDR(m, M_DONTWAIT, MT_DATA);
        if (m == 0) {
                aprint_error_dev(sc->sc_dev,
                    "cs_process_rx_early: unable to allocate mbuf\n");
                if_statinc(ifp, if_ierrors);
                /*
                 * Couldn't allocate an mbuf so things are not good, may as
                 * well drop the packet I think.
                 *
                 * have already read the length so we should be right to skip
                 * the packet.
                 */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                    CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG) | RX_CFG_SKIP);
                return;
        }
        m_set_rcvif(m, ifp);
        /*
         * Save processing by always using a mbuf cluster, guaranteed to fit
         * packet
         */
        MCLGET(m, M_DONTWAIT);
        if ((m->m_flags & M_EXT) == 0) {
                /* Couldn't allocate an mbuf cluster */
                aprint_error_dev(sc->sc_dev,
                    "cs_process_rx_early: unable to allocate a cluster\n");
                m_freem(m);
                /* Skip the frame */
                CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG,
                    CS_READ_PACKET_PAGE(sc, PKTPG_RX_CFG) | RX_CFG_SKIP);
                return;
        }

        /* Align ip header on word boundary for ipintr */
        pad = ALIGN(sizeof(struct ether_header)) - sizeof(struct ether_header);
        m->m_data += pad;

        /* Set up the buffer pointer to point to the data area */
        pBuff = mtod(m, uint16_t *);

        /*
         * Now read the frame byte counter until we have finished reading the
         * frame
         */
        oldFrameCount = 0;
        frameCount = CS_READ_PACKET_PAGE(sc, PKTPG_FRAME_BYTE_COUNT);
        while ((frameCount != 0) && (frameCount < MCLBYTES)) {
                for (; oldFrameCount < frameCount; oldFrameCount += 2) {
                        *pBuff++ = CS_READ_PACKET_PAGE(sc, frameOffset);
                        frameOffset += 2;
                }

                /* Read the new count from the chip */
                frameCount = CS_READ_PACKET_PAGE(sc, PKTPG_FRAME_BYTE_COUNT);
        }

        /* Update the mbuf counts */
        m->m_len = oldFrameCount;
        m->m_pkthdr.len = oldFrameCount;

        /* Now check the Rx Event register */
        rxEvent = CS_READ_PACKET_PAGE(sc, PKTPG_RX_EVENT);

        if ((rxEvent & RX_EVENT_RX_OK) != 0) {
                /*
                 * Do an implied skip, it seems to be more reliable than a
                 * forced skip.
                 */
                rxEvent = CS_READ_PACKET_PAGE(sc, PKTPG_RX_STATUS);
                rxEvent = CS_READ_PACKET_PAGE(sc, PKTPG_RX_LENGTH);

                /*
                 * Now read the RX_EVENT register to perform an implied skip.
                 */
                rxEvent = CS_READ_PACKET_PAGE(sc, PKTPG_RX_EVENT);

                cs_ether_input(sc, m);
        } else {
                m_freem(m);
                if_statinc(ifp, if_ierrors);
        }
}

void
cs_start_output(struct ifnet *ifp)
{
        struct cs_softc *sc;
        struct mbuf *pMbuf;
        struct mbuf *pMbufChain;
        uint16_t BusStatus;
        uint16_t Length;
        int txLoop = 0;
        int dropout = 0;

        sc = ifp->if_softc;

        /* Check that the interface is up and running */
        if ((ifp->if_flags & IFF_RUNNING) == 0)
                return;

        /* Don't interrupt a transmission in progress */
        if (sc->sc_txbusy)
                return;

        /* This loop will only run through once if transmission is successful */
        /*
         * While there are packets to transmit and a transmit is not in
         * progress
         */
        while (sc->sc_txbusy == 0 && dropout == 0) {
                IFQ_DEQUEUE(&ifp->if_snd, pMbufChain);
                if (pMbufChain == NULL)
                        break;

                /*
                 * If BPF is listening on this interface, let it see the packet
                 * before we commit it to the wire.
                 */
                bpf_mtap(ifp, pMbufChain, BPF_D_OUT);

                /* Find the total length of the data to transmit */
                Length = 0;
                for (pMbuf = pMbufChain; pMbuf != NULL; pMbuf = pMbuf->m_next)
                        Length += pMbuf->m_len;

                do {
                        /*
                         * Request that the transmit be started after all
                         * data has been copied
                         *
                         * In IO mode must write to the IO port not the packet
                         * page address
                         *
                         * If this is changed to start transmission after a
                         * small amount of data has been copied you tend to
                         * get packet missed errors i think because the ISA
                         * bus is too slow. Or possibly the copy routine is
                         * not streamlined enough.
                         */
                        if (sc->sc_memorymode) {
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_TX_CMD,
                                    cs_xmit_early_table[sc->sc_xe_ent].txcmd);
                                CS_WRITE_PACKET_PAGE(sc, PKTPG_TX_LENGTH, Length);
                        } else {
                                CS_WRITE_PORT(sc, PORT_TX_CMD,
                                    cs_xmit_early_table[sc->sc_xe_ent].txcmd);
                                CS_WRITE_PORT(sc, PORT_TX_LENGTH, Length);
                        }

                        /* Adjust early-transmit machinery. */
                        if (--sc->sc_xe_togo == 0) {
                                sc->sc_xe_ent =
                                    cs_xmit_early_table[sc->sc_xe_ent].better;
                                sc->sc_xe_togo =
                            cs_xmit_early_table[sc->sc_xe_ent].better_count;
                        }
                        /*
                         * Read the BusStatus register which indicates
                         * success of the request
                         */
                        BusStatus = CS_READ_PACKET_PAGE(sc, PKTPG_BUS_ST);

                        /*
                         * If there was an error in the transmit bid free the
                         * mbuf and go on. This is presuming that mbuf is
                         * corrupt.
                         */
                        if (BusStatus & BUS_ST_TX_BID_ERR) {
                                aprint_error_dev(sc->sc_dev,
                                    "transmit bid error (too big)");

                                /* Discard the bad mbuf chain */
                                m_freem(pMbufChain);
                                if_statinc(&sc->sc_ethercom.ec_if, if_oerrors);

                                /* Loop up to transmit the next chain */
                                txLoop = 0;
                        } else {
                                if (BusStatus & BUS_ST_RDY4TXNOW) {
                                        /*
                                         * The chip is ready for transmission
                                         * now
                                         */
                                        /*
                                         * Copy the frame to the chip to
                                         * start transmission
                                         */
                                        cs_copy_tx_frame(sc, pMbufChain);

                                        /* Free the mbuf chain */
                                        m_freem(pMbufChain);

                                        /* Transmission is now in progress */
                                        sc->sc_txbusy = TRUE;
                                        txLoop = 0;
                                } else {
                                        /*
                                         * If we get here we want to try
                                         * again with the same mbuf, until
                                         * the chip lets us transmit.
                                         */
                                        txLoop++;
                                        if (txLoop > CS_OUTPUT_LOOP_MAX) {
                                                /* Free the mbuf chain */
                                                m_freem(pMbufChain);
                                                /*
                                                 * Transmission is not in
                                                 * progress
                                                 */
                                                sc->sc_txbusy = FALSE;
                                                /*
                                                 * Increment the output error
                                                 * count
                                                 */
                                                if_statinc(ifp, if_oerrors);
                                                /*
                                                 * exit the routine and drop
                                                 * the packet.
                                                 */
                                                txLoop = 0;
                                                dropout = 1;
                                        }
                                }
                        }
                } while (txLoop);
        }
}

void
cs_copy_tx_frame(struct cs_softc *sc, struct mbuf *m0)
{
        struct mbuf *m;
        int len, leftover, frameoff;
        uint16_t dbuf;
        uint8_t *p;
#ifdef DIAGNOSTIC
        uint8_t *lim;
#endif

        /* Initialize frame pointer and data port address */
        frameoff = PKTPG_TX_FRAME;

        /* Start out with no leftover data */
        leftover = 0;
        dbuf = 0;

        /* Process the chain of mbufs */
        for (m = m0; m != NULL; m = m->m_next) {
                /* Process all of the data in a single mbuf. */
                p = mtod(m, uint8_t *);
                len = m->m_len;
#ifdef DIAGNOSTIC
                lim = p + len;
#endif

                while (len > 0) {
                        if (leftover) {
                                /*
                                 * Data left over (from mbuf or realignment).
                                 * Buffer the next byte, and write it and
                                 * the leftover data out.
                                 */
                                dbuf |= *p++ << 8;
                                len--;
                                if (sc->sc_memorymode) {
                                        CS_WRITE_PACKET_PAGE(sc, frameoff, dbuf);
                                        frameoff += 2;
                                }
                                else {
                                        CS_WRITE_PORT(sc, PORT_RXTX_DATA, dbuf);
                                }
                                leftover = 0;
                        } else if ((long) p & 1) {
                                /* Misaligned data.  Buffer the next byte. */
                                dbuf = *p++;
                                len--;
                                leftover = 1;
                        } else {
                                /*
                                 * Aligned data.  This is the case we like.
                                 *
                                 * Write-region out as much as we can, then
                                 * buffer the remaining byte (if any).
                                 */
                                leftover = len & 1;
                                len &= ~1;
                                if (sc->sc_memorymode) {
                                        MEM_WRITE_REGION_2(sc, frameoff,
                                            (uint16_t *) p, len >> 1);
                                        frameoff += len;
                                } else
                                        IO_WRITE_MULTI_2(sc, PORT_RXTX_DATA,
                                            (uint16_t *)p, len >> 1);
                                p += len;

                                if (leftover)
                                        dbuf = *p++;
                                len = 0;
                        }
                }
                if (len < 0)
                        panic("cs_copy_tx_frame: negative len");
#ifdef DIAGNOSTIC
                if (p != lim)
                        panic("cs_copy_tx_frame: p != lim");
#endif
        }
        if (leftover) {
                if (sc->sc_memorymode)
                        CS_WRITE_PACKET_PAGE(sc, frameoff, dbuf);
                else
                        CS_WRITE_PORT(sc, PORT_RXTX_DATA, dbuf);
        }
}

static int
cs_enable(struct cs_softc *sc)
{

        if (CS_IS_ENABLED(sc) == 0) {
                if (sc->sc_enable != NULL) {
                        int error;

                        error = (*sc->sc_enable)(sc);
                        if (error)
                                return error;
                }
                sc->sc_cfgflags |= CFGFLG_ENABLED;
        }

        return 0;
}

static void
cs_disable(struct cs_softc *sc)
{

        if (CS_IS_ENABLED(sc)) {
                if (sc->sc_disable != NULL)
                        (*sc->sc_disable)(sc);

                sc->sc_cfgflags &= ~CFGFLG_ENABLED;
        }
}

static void
cs_stop(struct ifnet *ifp, int disable)
{
        struct cs_softc *sc = ifp->if_softc;

        CS_WRITE_PACKET_PAGE(sc, PKTPG_RX_CFG, 0);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_TX_CFG, 0);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_BUF_CFG, 0);
        CS_WRITE_PACKET_PAGE(sc, PKTPG_BUS_CTL, 0);

        if (disable)
                cs_disable(sc);

        ifp->if_flags &= ~IFF_RUNNING;
}

int
cs_activate(device_t self, enum devact act)
{
        struct cs_softc *sc = device_private(self);

        switch (act) {
        case DVACT_DEACTIVATE:
                if_deactivate(&sc->sc_ethercom.ec_if);
                return 0;
        default:
                return EOPNOTSUPP;
        }
}