pxe_undi.c

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/** @file
 *
 * PXE UNDI API
 *
 */

/*
 * Copyright (C) 2004 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <byteswap.h>
#include <basemem_packet.h>
#include <gpxe/netdevice.h>
#include <gpxe/iobuf.h>
#include <gpxe/device.h>
#include <gpxe/pci.h>
#include <gpxe/if_ether.h>
#include <gpxe/ip.h>
#include <gpxe/arp.h>
#include <gpxe/rarp.h>
#include "pxe.h"

/**
 * Count of outstanding transmitted packets
 *
 * This is incremented each time PXENV_UNDI_TRANSMIT is called, and
 * decremented each time that PXENV_UNDI_ISR is called with the TX
 * queue empty, stopping when the count reaches zero.  This allows us
 * to provide a pessimistic approximation of TX completion events to
 * the PXE NBP simply by monitoring the netdev's TX queue.
 */
static int undi_tx_count = 0;

struct net_device *pxe_netdev = NULL;

/**
 * Set network device as current PXE network device
 *
 * @v netdev            Network device, or NULL
 */
void pxe_set_netdev ( struct net_device *netdev ) {
        if ( pxe_netdev )
                netdev_put ( pxe_netdev );
        pxe_netdev = NULL;
        if ( netdev )
                pxe_netdev = netdev_get ( netdev );
}

/**
 * Open PXE network device
 *
 * @ret rc              Return status code
 */
static int pxe_netdev_open ( void ) {
        int rc;

        if ( ( rc = netdev_open ( pxe_netdev ) ) != 0 )
                return rc;

        netdev_irq ( pxe_netdev, 1 );
        return 0;
}

/**
 * Close PXE network device
 *
 */
static void pxe_netdev_close ( void ) {
        netdev_irq ( pxe_netdev, 0 );
        netdev_close ( pxe_netdev );
        undi_tx_count = 0;
}

/**
 * Dump multicast address list
 *
 * @v mcast             PXE multicast address list
 */
static void pxe_dump_mcast_list ( struct s_PXENV_UNDI_MCAST_ADDRESS *mcast ) {
        struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;
        unsigned int i;

        for ( i = 0 ; i < mcast->MCastAddrCount ; i++ ) {
                DBG ( " %s", ll_protocol->ntoa ( mcast->McastAddr[i] ) );
        }
}

/* PXENV_UNDI_STARTUP
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_startup ( struct s_PXENV_UNDI_STARTUP *undi_startup ) {
        DBG ( "PXENV_UNDI_STARTUP\n" );

        undi_startup->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_CLEANUP
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_cleanup ( struct s_PXENV_UNDI_CLEANUP *undi_cleanup ) {
        DBG ( "PXENV_UNDI_CLEANUP\n" );

        pxe_netdev_close();

        undi_cleanup->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_INITIALIZE
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_initialize ( struct s_PXENV_UNDI_INITIALIZE
                                     *undi_initialize ) {
        DBG ( "PXENV_UNDI_INITIALIZE protocolini %08x\n",
              undi_initialize->ProtocolIni );

        undi_initialize->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_RESET_ADAPTER
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_reset_adapter ( struct s_PXENV_UNDI_RESET
                                        *undi_reset_adapter ) {
        int rc;

        DBG ( "PXENV_UNDI_RESET_ADAPTER" );
        pxe_dump_mcast_list ( &undi_reset_adapter->R_Mcast_Buf );
        DBG ( "\n" );

        pxe_netdev_close();
        if ( ( rc = pxe_netdev_open() ) != 0 ) {
                DBG ( "PXENV_UNDI_RESET_ADAPTER could not reopen %s: %s\n",
                      pxe_netdev->name, strerror ( rc ) );
                undi_reset_adapter->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        undi_reset_adapter->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_SHUTDOWN
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_shutdown ( struct s_PXENV_UNDI_SHUTDOWN
                                   *undi_shutdown ) {
        DBG ( "PXENV_UNDI_SHUTDOWN\n" );

        pxe_netdev_close();

        undi_shutdown->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_OPEN
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_open ( struct s_PXENV_UNDI_OPEN *undi_open ) {
        int rc;

        DBG ( "PXENV_UNDI_OPEN flag %04x filter %04x",
              undi_open->OpenFlag, undi_open->PktFilter );
        pxe_dump_mcast_list ( &undi_open->R_Mcast_Buf );
        DBG ( "\n" );

        if ( ( rc = pxe_netdev_open() ) != 0 ) {
                DBG ( "PXENV_UNDI_OPEN could not open %s: %s\n",
                      pxe_netdev->name, strerror ( rc ) );
                undi_open->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        undi_open->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_CLOSE
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_close ( struct s_PXENV_UNDI_CLOSE *undi_close ) {
        DBG ( "PXENV_UNDI_CLOSE\n" );

        pxe_netdev_close();

        undi_close->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_TRANSMIT
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_transmit ( struct s_PXENV_UNDI_TRANSMIT
                                   *undi_transmit ) {
        struct s_PXENV_UNDI_TBD tbd;
        struct DataBlk *datablk;
        struct io_buffer *iobuf;
        struct net_protocol *net_protocol;
        struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;
        char destaddr[MAX_LL_ADDR_LEN];
        const void *ll_dest;
        size_t ll_hlen = ll_protocol->ll_header_len;
        size_t len;
        unsigned int i;
        int rc;

        DBG2 ( "PXENV_UNDI_TRANSMIT" );

        /* Forcibly enable interrupts at this point, to work around
         * callers that never call PXENV_UNDI_OPEN before attempting
         * to use the UNDI API.
         */
        netdev_irq ( pxe_netdev, 1 );

        /* Identify network-layer protocol */
        switch ( undi_transmit->Protocol ) {
        case P_IP:      net_protocol = &ipv4_protocol;  break;
        case P_ARP:     net_protocol = &arp_protocol;   break;
        case P_RARP:    net_protocol = &rarp_protocol;  break;
        case P_UNKNOWN:
                net_protocol = NULL;
                ll_hlen = 0;
                break;
        default:
                DBG2 ( " %02x invalid protocol\n", undi_transmit->Protocol );
                undi_transmit->Status = PXENV_STATUS_UNDI_INVALID_PARAMETER;
                return PXENV_EXIT_FAILURE;
        }
        DBG2 ( " %s", ( net_protocol ? net_protocol->name : "RAW" ) );

        /* Calculate total packet length */
        copy_from_real ( &tbd, undi_transmit->TBD.segment,
                         undi_transmit->TBD.offset, sizeof ( tbd ) );
        len = tbd.ImmedLength;
        DBG2 ( " %04x:%04x+%x", tbd.Xmit.segment, tbd.Xmit.offset,
               tbd.ImmedLength );
        for ( i = 0 ; i < tbd.DataBlkCount ; i++ ) {
                datablk = &tbd.DataBlock[i];
                len += datablk->TDDataLen;
                DBG2 ( " %04x:%04x+%x", datablk->TDDataPtr.segment,
                       datablk->TDDataPtr.offset, datablk->TDDataLen );
        }

        /* Allocate and fill I/O buffer */
        iobuf = alloc_iob ( ll_hlen + len );
        if ( ! iobuf ) {
                DBG2 ( " could not allocate iobuf\n" );
                undi_transmit->Status = PXENV_STATUS_OUT_OF_RESOURCES;
                return PXENV_EXIT_FAILURE;
        }
        iob_reserve ( iobuf, ll_hlen );
        copy_from_real ( iob_put ( iobuf, tbd.ImmedLength ), tbd.Xmit.segment,
                         tbd.Xmit.offset, tbd.ImmedLength );
        for ( i = 0 ; i < tbd.DataBlkCount ; i++ ) {
                datablk = &tbd.DataBlock[i];
                copy_from_real ( iob_put ( iobuf, datablk->TDDataLen ),
                                 datablk->TDDataPtr.segment,
                                 datablk->TDDataPtr.offset,
                                 datablk->TDDataLen );
        }

        /* Add link-layer header, if required to do so */
        if ( net_protocol != NULL ) {

                /* Calculate destination address */
                if ( undi_transmit->XmitFlag == XMT_DESTADDR ) {
                        copy_from_real ( destaddr,
                                         undi_transmit->DestAddr.segment,
                                         undi_transmit->DestAddr.offset,
                                         ll_protocol->ll_addr_len );
                        ll_dest = destaddr;
                        DBG2 ( " DEST %s", ll_protocol->ntoa ( ll_dest ) );
                } else {
                        ll_dest = pxe_netdev->ll_broadcast;
                        DBG2 ( " BCAST" );
                }

                /* Add link-layer header */
                if ( ( rc = ll_protocol->push ( pxe_netdev, iobuf, ll_dest,
                                                pxe_netdev->ll_addr,
                                                net_protocol->net_proto ))!=0){
                        DBG2 ( " could not add link-layer header: %s\n",
                               strerror ( rc ) );
                        free_iob ( iobuf );
                        undi_transmit->Status = PXENV_STATUS ( rc );
                        return PXENV_EXIT_FAILURE;
                }
        }

        /* Flag transmission as in-progress.  Do this before starting
         * to transmit the packet, because the ISR may trigger before
         * we return from netdev_tx().
         */
        undi_tx_count++;

        /* Transmit packet */
        DBG2 ( "\n" );
        if ( ( rc = netdev_tx ( pxe_netdev, iobuf ) ) != 0 ) {
                DBG2 ( "PXENV_UNDI_TRANSMIT could not transmit: %s\n",
                       strerror ( rc ) );
                undi_tx_count--;
                undi_transmit->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }

        undi_transmit->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_SET_MCAST_ADDRESS
 *
 * Status: working (for NICs that support receive-all-multicast)
 */
PXENV_EXIT_t
pxenv_undi_set_mcast_address ( struct s_PXENV_UNDI_SET_MCAST_ADDRESS
                               *undi_set_mcast_address ) {
        DBG ( "PXENV_UNDI_SET_MCAST_ADDRESS" );
        pxe_dump_mcast_list ( &undi_set_mcast_address->R_Mcast_Buf );
        DBG ( "\n" );

        undi_set_mcast_address->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_SET_STATION_ADDRESS
 *
 * Status: working
 */
PXENV_EXIT_t 
pxenv_undi_set_station_address ( struct s_PXENV_UNDI_SET_STATION_ADDRESS
                                 *undi_set_station_address ) {
        struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;

        DBG ( "PXENV_UNDI_SET_STATION_ADDRESS %s",
              ll_protocol->ntoa ( undi_set_station_address->StationAddress ) );

        /* If adapter is open, the change will have no effect; return
         * an error
         */
        if ( netdev_is_open ( pxe_netdev ) ) {
                DBG ( " failed: netdev is open\n" );
                undi_set_station_address->Status =
                        PXENV_STATUS_UNDI_INVALID_STATE;
                return PXENV_EXIT_FAILURE;
        }

        /* Update MAC address */
        memcpy ( pxe_netdev->ll_addr,
                 &undi_set_station_address->StationAddress,
                 ll_protocol->ll_addr_len );

        DBG ( "\n" );
        undi_set_station_address->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_SET_PACKET_FILTER
 *
 * Status: won't implement (would require driver API changes for no
 * real benefit)
 */
PXENV_EXIT_t
pxenv_undi_set_packet_filter ( struct s_PXENV_UNDI_SET_PACKET_FILTER
                               *undi_set_packet_filter ) {

        DBG ( "PXENV_UNDI_SET_PACKET_FILTER %02x\n",
              undi_set_packet_filter->filter );

        /* Pretend that we succeeded, otherwise the 3Com DOS UNDI
         * driver refuses to load.  (We ignore the filter value in the
         * PXENV_UNDI_OPEN call anyway.)
         */
        undi_set_packet_filter->Status = PXENV_STATUS_SUCCESS;

        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_GET_INFORMATION
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_get_information ( struct s_PXENV_UNDI_GET_INFORMATION
                                          *undi_get_information ) {
        struct device *dev = pxe_netdev->dev;
        struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;
        size_t ll_addr_len = ll_protocol->ll_addr_len;

        DBG ( "PXENV_UNDI_GET_INFORMATION" );

        undi_get_information->BaseIo = dev->desc.ioaddr;
        undi_get_information->IntNumber = dev->desc.irq;
        /* Cheat: assume all cards can cope with this */
        undi_get_information->MaxTranUnit = ETH_MAX_MTU;
        undi_get_information->HwType = ntohs ( ll_protocol->ll_proto );
        undi_get_information->HwAddrLen = ll_addr_len;
        assert ( ll_addr_len <=
                 sizeof ( undi_get_information->CurrentNodeAddress ) );
        memcpy ( &undi_get_information->CurrentNodeAddress,
                 pxe_netdev->ll_addr,
                 sizeof ( undi_get_information->CurrentNodeAddress ) );
        ll_protocol->init_addr ( pxe_netdev->hw_addr,
                                 &undi_get_information->PermNodeAddress );
        undi_get_information->ROMAddress = 0;
                /* nic.rom_info->rom_segment; */
        /* We only provide the ability to receive or transmit a single
         * packet at a time.  This is a bootloader, not an OS.
         */
        undi_get_information->RxBufCt = 1;
        undi_get_information->TxBufCt = 1;

        DBG ( " io %04x irq %d mtu %d %s %s\n",
              undi_get_information->BaseIo, undi_get_information->IntNumber,
              undi_get_information->MaxTranUnit, ll_protocol->name,
              ll_protocol->ntoa ( &undi_get_information->CurrentNodeAddress ));
        undi_get_information->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_GET_STATISTICS
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_get_statistics ( struct s_PXENV_UNDI_GET_STATISTICS
                                         *undi_get_statistics ) {
        DBG ( "PXENV_UNDI_GET_STATISTICS" );

        undi_get_statistics->XmtGoodFrames = pxe_netdev->tx_stats.good;
        undi_get_statistics->RcvGoodFrames = pxe_netdev->rx_stats.good;
        undi_get_statistics->RcvCRCErrors = pxe_netdev->rx_stats.bad;
        undi_get_statistics->RcvResourceErrors = pxe_netdev->rx_stats.bad;

        DBG ( " txok %d rxok %d rxcrc %d rxrsrc %d\n",
              undi_get_statistics->XmtGoodFrames,
              undi_get_statistics->RcvGoodFrames,
              undi_get_statistics->RcvCRCErrors,
              undi_get_statistics->RcvResourceErrors );
        undi_get_statistics->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_CLEAR_STATISTICS
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_clear_statistics ( struct s_PXENV_UNDI_CLEAR_STATISTICS
                                           *undi_clear_statistics ) {
        DBG ( "PXENV_UNDI_CLEAR_STATISTICS\n" );

        memset ( &pxe_netdev->tx_stats, 0, sizeof ( pxe_netdev->tx_stats ) );
        memset ( &pxe_netdev->rx_stats, 0, sizeof ( pxe_netdev->rx_stats ) );

        undi_clear_statistics->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_INITIATE_DIAGS
 *
 * Status: won't implement (would require driver API changes for no
 * real benefit)
 */
PXENV_EXIT_t pxenv_undi_initiate_diags ( struct s_PXENV_UNDI_INITIATE_DIAGS
                                         *undi_initiate_diags ) {
        DBG ( "PXENV_UNDI_INITIATE_DIAGS failed: unsupported\n" );

        undi_initiate_diags->Status = PXENV_STATUS_UNSUPPORTED;
        return PXENV_EXIT_FAILURE;
}

/* PXENV_UNDI_FORCE_INTERRUPT
 *
 * Status: won't implement (would require driver API changes for no
 * perceptible benefit)
 */
PXENV_EXIT_t pxenv_undi_force_interrupt ( struct s_PXENV_UNDI_FORCE_INTERRUPT
                                          *undi_force_interrupt ) {
        DBG ( "PXENV_UNDI_FORCE_INTERRUPT failed: unsupported\n" );

        undi_force_interrupt->Status = PXENV_STATUS_UNSUPPORTED;
        return PXENV_EXIT_FAILURE;
}

/* PXENV_UNDI_GET_MCAST_ADDRESS
 *
 * Status: working
 */
PXENV_EXIT_t
pxenv_undi_get_mcast_address ( struct s_PXENV_UNDI_GET_MCAST_ADDRESS
                               *undi_get_mcast_address ) {
        struct ll_protocol *ll_protocol = pxe_netdev->ll_protocol;
        struct in_addr ip = { .s_addr = undi_get_mcast_address->InetAddr };
        int rc;

        DBG ( "PXENV_UNDI_GET_MCAST_ADDRESS %s", inet_ntoa ( ip ) );

        if ( ( rc = ll_protocol->mc_hash ( AF_INET, &ip,
                                      undi_get_mcast_address->MediaAddr ))!=0){
                DBG ( " failed: %s\n", strerror ( rc ) );
                undi_get_mcast_address->Status = PXENV_STATUS ( rc );
                return PXENV_EXIT_FAILURE;
        }
        DBG ( "=>%s\n",
              ll_protocol->ntoa ( undi_get_mcast_address->MediaAddr ) );

        undi_get_mcast_address->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_GET_NIC_TYPE
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_get_nic_type ( struct s_PXENV_UNDI_GET_NIC_TYPE
                                       *undi_get_nic_type ) {
        struct device *dev = pxe_netdev->dev;

        DBG ( "PXENV_UNDI_GET_NIC_TYPE" );

        memset ( &undi_get_nic_type->info, 0,
                 sizeof ( undi_get_nic_type->info ) );

        switch ( dev->desc.bus_type ) {
        case BUS_TYPE_PCI: {
                struct pci_nic_info *info = &undi_get_nic_type->info.pci;

                undi_get_nic_type->NicType = PCI_NIC;
                info->Vendor_ID = dev->desc.vendor;
                info->Dev_ID = dev->desc.device;
                info->Base_Class = PCI_BASE_CLASS ( dev->desc.class );
                info->Sub_Class = PCI_SUB_CLASS ( dev->desc.class );
                info->Prog_Intf = PCI_PROG_INTF ( dev->desc.class );
                info->BusDevFunc = dev->desc.location;
                /* Cheat: remaining fields are probably unnecessary,
                 * and would require adding extra code to pci.c.
                 */
                undi_get_nic_type->info.pci.SubVendor_ID = 0xffff;
                undi_get_nic_type->info.pci.SubDevice_ID = 0xffff;
                DBG ( " PCI %02x:%02x.%x %04x:%04x (%04x:%04x) %02x%02x%02x "
                      "rev %02x\n", PCI_BUS ( info->BusDevFunc ),
                      PCI_SLOT ( info->BusDevFunc ),
                      PCI_FUNC ( info->BusDevFunc ), info->Vendor_ID,
                      info->Dev_ID, info->SubVendor_ID, info->SubDevice_ID,
                      info->Base_Class, info->Sub_Class, info->Prog_Intf,
                      info->Rev );
                break; }
        case BUS_TYPE_ISAPNP: {
                struct pnp_nic_info *info = &undi_get_nic_type->info.pnp;

                undi_get_nic_type->NicType = PnP_NIC;
                info->EISA_Dev_ID = ( ( dev->desc.vendor << 16 ) |
                                      dev->desc.device );
                info->CardSelNum = dev->desc.location;
                /* Cheat: remaining fields are probably unnecessary,
                 * and would require adding extra code to isapnp.c.
                 */
                DBG ( " ISAPnP CSN %04x %08x %02x%02x%02x\n",
                      info->CardSelNum, info->EISA_Dev_ID,
                      info->Base_Class, info->Sub_Class, info->Prog_Intf );
                break; }
        default:
                DBG ( " failed: unknown bus type\n" );
                undi_get_nic_type->Status = PXENV_STATUS_FAILURE;
                return PXENV_EXIT_FAILURE;
        }

        undi_get_nic_type->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_GET_IFACE_INFO
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_get_iface_info ( struct s_PXENV_UNDI_GET_IFACE_INFO
                                         *undi_get_iface_info ) {
        DBG ( "PXENV_UNDI_GET_IFACE_INFO" );

        /* Just hand back some info, doesn't really matter what it is.
         * Most PXE stacks seem to take this approach.
         */
        snprintf ( ( char * ) undi_get_iface_info->IfaceType,
                   sizeof ( undi_get_iface_info->IfaceType ), "DIX+802.3" );
        undi_get_iface_info->LinkSpeed = 10000000; /* 10 Mbps */
        undi_get_iface_info->ServiceFlags =
                ( SUPPORTED_BROADCAST | SUPPORTED_MULTICAST |
                  SUPPORTED_SET_STATION_ADDRESS | SUPPORTED_RESET |
                  SUPPORTED_OPEN_CLOSE | SUPPORTED_IRQ );
        memset ( undi_get_iface_info->Reserved, 0,
                 sizeof(undi_get_iface_info->Reserved) );

        DBG ( " %s %dbps flags %08x\n", undi_get_iface_info->IfaceType,
              undi_get_iface_info->LinkSpeed,
              undi_get_iface_info->ServiceFlags );
        undi_get_iface_info->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}

/* PXENV_UNDI_GET_STATE
 *
 * Status: impossible
 */
PXENV_EXIT_t pxenv_undi_get_state ( struct s_PXENV_UNDI_GET_STATE
                                    *undi_get_state ) {
        DBG ( "PXENV_UNDI_GET_STATE failed: unsupported\n" );

        undi_get_state->Status = PXENV_STATUS_UNSUPPORTED;
        return PXENV_EXIT_FAILURE;
};

/* PXENV_UNDI_ISR
 *
 * Status: working
 */
PXENV_EXIT_t pxenv_undi_isr ( struct s_PXENV_UNDI_ISR *undi_isr ) {
        struct io_buffer *iobuf;
        size_t len;
        struct ll_protocol *ll_protocol;
        const void *ll_dest;
        const void *ll_source;
        uint16_t net_proto;
        size_t ll_hlen;
        struct net_protocol *net_protocol;
        unsigned int prottype;
        int rc;

        /* Use coloured debug, since UNDI ISR messages are likely to
         * be interspersed amongst other UNDI messages.
         */
        DBGC2 ( &pxenv_undi_isr, "PXENV_UNDI_ISR" );

        /* Just in case some idiot actually looks at these fields when
         * we weren't meant to fill them in...
         */
        undi_isr->BufferLength = 0;
        undi_isr->FrameLength = 0;
        undi_isr->FrameHeaderLength = 0;
        undi_isr->ProtType = 0;
        undi_isr->PktType = 0;

        switch ( undi_isr->FuncFlag ) {
        case PXENV_UNDI_ISR_IN_START :
                DBGC2 ( &pxenv_undi_isr, " START" );

                /* Call poll().  This should acknowledge the device
                 * interrupt and queue up any received packet.
                 */
                netdev_poll ( pxe_netdev );

                /* A 100% accurate determination of "OURS" vs "NOT
                 * OURS" is difficult to achieve without invasive and
                 * unpleasant changes to the driver model.  We settle
                 * for always returning "OURS" if interrupts are
                 * currently enabled.
                 *
                 * Returning "NOT OURS" when interrupts are disabled
                 * allows us to avoid a potential interrupt storm when
                 * we are on a shared interrupt line; if we were to
                 * always return "OURS" then the other device's ISR
                 * may never be called.
                 */
                if ( netdev_irq_enabled ( pxe_netdev ) ) {
                        DBGC2 ( &pxenv_undi_isr, " OURS" );
                        undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_OURS;
                } else {
                        DBGC2 ( &pxenv_undi_isr, " NOT OURS" );
                        undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_NOT_OURS;
                }

                /* Disable interrupts */
                netdev_irq ( pxe_netdev, 0 );

                break;
        case PXENV_UNDI_ISR_IN_PROCESS :
        case PXENV_UNDI_ISR_IN_GET_NEXT :
                DBGC2 ( &pxenv_undi_isr, " %s",
                        ( ( undi_isr->FuncFlag == PXENV_UNDI_ISR_IN_PROCESS ) ?
                          "PROCESS" : "GET_NEXT" ) );

                /* Some dumb NBPs (e.g. emBoot's winBoot/i) never call
                 * PXENV_UNDI_ISR with FuncFlag=PXENV_UNDI_ISR_START;
                 * they just sit in a tight polling loop merrily
                 * violating the PXE spec with repeated calls to
                 * PXENV_UNDI_ISR_IN_PROCESS.  Force extra polls to
                 * cope with these out-of-spec clients.
                 */
                netdev_poll ( pxe_netdev );

                /* If we have not yet marked a TX as complete, and the
                 * netdev TX queue is empty, report the TX completion.
                 */
                if ( undi_tx_count && list_empty ( &pxe_netdev->tx_queue ) ) {
                        DBGC2 ( &pxenv_undi_isr, " TXC" );
                        undi_tx_count--;
                        undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_TRANSMIT;
                        break;
                }

                /* Remove first packet from netdev RX queue */
                iobuf = netdev_rx_dequeue ( pxe_netdev );
                if ( ! iobuf ) {
                        DBGC2 ( &pxenv_undi_isr, " DONE" );
                        /* No more packets remaining */
                        undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_DONE;
                        /* Re-enable interrupts */
                        netdev_irq ( pxe_netdev, 1 );
                        break;
                }

                /* Copy packet to base memory buffer */
                len = iob_len ( iobuf );
                DBGC2 ( &pxenv_undi_isr, " RX" );
                if ( len > sizeof ( basemem_packet ) ) {
                        /* Should never happen */
                        DBGC2 ( &pxenv_undi_isr, " overlength (%zx)", len );
                        len = sizeof ( basemem_packet );
                }
                memcpy ( basemem_packet, iobuf->data, len );

                /* Strip link-layer header */
                ll_protocol = pxe_netdev->ll_protocol;
                if ( ( rc = ll_protocol->pull ( pxe_netdev, iobuf, &ll_dest,
                                                &ll_source, &net_proto )) !=0){
                        /* Assume unknown net_proto and no ll_source */
                        net_proto = 0;
                        ll_source = NULL;
                }
                ll_hlen = ( len - iob_len ( iobuf ) );

                /* Determine network-layer protocol */
                switch ( net_proto ) {
                case htons ( ETH_P_IP ):
                        net_protocol = &ipv4_protocol;
                        prottype = P_IP;
                        break;
                case htons ( ETH_P_ARP ):
                        net_protocol = &arp_protocol;
                        prottype = P_ARP;
                        break;
                case htons ( ETH_P_RARP ):
                        net_protocol = &rarp_protocol;
                        prottype = P_RARP;
                        break;
                default:
                        net_protocol = NULL;
                        prottype = P_UNKNOWN;
                        break;
                }

                /* Fill in UNDI_ISR structure */
                undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_RECEIVE;
                undi_isr->BufferLength = len;
                undi_isr->FrameLength = len;
                undi_isr->FrameHeaderLength = ll_hlen;
                undi_isr->Frame.segment = rm_ds;
                undi_isr->Frame.offset = __from_data16 ( basemem_packet );
                undi_isr->ProtType = prottype;
                undi_isr->PktType = XMT_DESTADDR;
                DBGC2 ( &pxenv_undi_isr, " %04x:%04x+%x(%x) %s hlen %d",
                        undi_isr->Frame.segment, undi_isr->Frame.offset,
                        undi_isr->BufferLength, undi_isr->FrameLength,
                        ( net_protocol ? net_protocol->name : "RAW" ),
                        undi_isr->FrameHeaderLength );

                /* Free packet */
                free_iob ( iobuf );
                break;
        default :
                DBGC2 ( &pxenv_undi_isr, " INVALID(%04x)\n",
                        undi_isr->FuncFlag );

                /* Should never happen */
                undi_isr->FuncFlag = PXENV_UNDI_ISR_OUT_DONE;
                undi_isr->Status = PXENV_STATUS_UNDI_INVALID_PARAMETER;
                return PXENV_EXIT_FAILURE;
        }

        DBGC2 ( &pxenv_undi_isr, "\n" );
        undi_isr->Status = PXENV_STATUS_SUCCESS;
        return PXENV_EXIT_SUCCESS;
}