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      1 /**************************************************************************
      2 Etherboot -  BOOTP/TFTP Bootstrap Program
      3 Schneider & Koch G16 NIC driver for Etherboot
      4 heavily based on SK G16 driver from Linux 2.0.36
      5 Changes to make it work with Etherboot by Georg Baum <Georg.Baum (at) gmx.de>
      6 ***************************************************************************/
      7 
      8 /*-
      9  * Copyright (C) 1994 by PJD Weichmann & SWS Bern, Switzerland
     10  *
     11  * This software may be used and distributed according to the terms
     12  * of the GNU Public License, incorporated herein by reference.
     13  *
     14  * Module         : sk_g16.c
     15  *
     16  * Version        : $Revision: 1.4 $
     17  *
     18  * Author         : Patrick J.D. Weichmann
     19  *
     20  * Date Created   : 94/05/26
     21  * Last Updated   : $Date: 2002/01/02 21:56:40 $
     22  *
     23  * Description    : Schneider & Koch G16 Ethernet Device Driver for
     24  *                  Linux Kernel >= 1.1.22
     25  * Update History :
     26  *
     27 -*/
     28 
     29 /*
     30  * The Schneider & Koch (SK) G16 Network device driver is based
     31  * on the 'ni6510' driver from Michael Hipp which can be found at
     32  * ftp://sunsite.unc.edu/pub/Linux/system/Network/drivers/nidrivers.tar.gz
     33  *
     34  * Sources: 1) ni6510.c by M. Hipp
     35  *          2) depca.c  by D.C. Davies
     36  *          3) skeleton.c by D. Becker
     37  *          4) Am7990 Local Area Network Controller for Ethernet (LANCE),
     38  *             AMD, Pub. #05698, June 1989
     39  *
     40  * Many Thanks for helping me to get things working to:
     41  *
     42  *                 A. Cox (A.Cox (at) swansea.ac.uk)
     43  *                 M. Hipp (mhipp (at) student.uni-tuebingen.de)
     44  *                 R. Bolz (Schneider & Koch, Germany)
     45  *
     46  * See README.sk_g16 for details about limitations and bugs for the
     47  * current version.
     48  *
     49  * To Do:
     50  *        - Support of SK_G8 and other SK Network Cards.
     51  *        - Autoset memory mapped RAM. Check for free memory and then
     52  *          configure RAM correctly.
     53  *        - SK_close should really set card in to initial state.
     54  *        - Test if IRQ 3 is not switched off. Use autoirq() functionality.
     55  *          (as in /drivers/net/skeleton.c)
     56  *        - Implement Multicast addressing. At minimum something like
     57  *          in depca.c.
     58  *        - Redo the statistics part.
     59  *        - Try to find out if the board is in 8 Bit or 16 Bit slot.
     60  *          If in 8 Bit mode don't use IRQ 11.
     61  *        - (Try to make it slightly faster.)
     62  */
     63 
     64 /* to get some global routines like printf */
     65 #include "etherboot.h"
     66 /* to get the interface to the body of the program */
     67 #include "nic.h"
     68 
     69 /* From linux/if_ether.h: */
     70 #define ETH_ZLEN	60		/* Min. octets in frame sans FCS */
     71 
     72 #include "sk_g16.h"
     73 
     74 /*
     75  * Schneider & Koch Card Definitions
     76  * =================================
     77  */
     78 
     79 #define SK_NAME   "SK_G16"
     80 
     81 /*
     82  * SK_G16 Configuration
     83  * --------------------
     84  */
     85 
     86 /*
     87  * Abbreviations
     88  * -------------
     89  *
     90  * RAM - used for the 16KB shared memory
     91  * Boot_ROM, ROM - are used for referencing the BootEPROM
     92  *
     93  * SK_ADDR is a symbolic constant used to configure
     94  * the behaviour of the driver and the SK_G16.
     95  *
     96  * SK_ADDR defines the address where the RAM will be mapped into the real
     97  *         host memory.
     98  *         valid addresses are from 0xa0000 to 0xfc000 in 16Kbyte steps.
     99  */
    100 
    101 #define SK_ADDR         0xcc000
    102 
    103 /*
    104  * In POS3 are bits A14-A19 of the address bus. These bits can be set
    105  * to choose the RAM address. That's why we only can choose the RAM address
    106  * in 16KB steps.
    107  */
    108 
    109 #define POS_ADDR       (rom_addr>>14)  /* Do not change this line */
    110 
    111 /*
    112  * SK_G16 I/O PORT's + IRQ's + Boot_ROM locations
    113  * ----------------------------------------------
    114  */
    115 
    116 /*
    117  * As nearly every card has also SK_G16 a specified I/O Port region and
    118  * only a few possible IRQ's.
    119  * In the Installation Guide from Schneider & Koch is listed a possible
    120  * Interrupt IRQ2. IRQ2 is always IRQ9 in boards with two cascaded interrupt
    121  * controllers. So we use in SK_IRQS IRQ9.
    122  */
    123 
    124 /* Don't touch any of the following #defines. */
    125 
    126 #define SK_IO_PORTS     { 0x100, 0x180, 0x208, 0x220, 0x288, 0x320, 0x328, 0x390, 0 }
    127 
    128 /*
    129  * SK_G16 POS REGISTERS
    130  * --------------------
    131  */
    132 
    133 /*
    134  * SK_G16 has a Programmable Option Select (POS) Register.
    135  * The POS is composed of 8 separate registers (POS0-7) which
    136  * are I/O mapped on an address set by the W1 switch.
    137  *
    138  */
    139 
    140 #define SK_POS_SIZE 8           /* 8 I/O Ports are used by SK_G16 */
    141 
    142 #define SK_POS0     ioaddr      /* Card-ID Low (R) */
    143 #define SK_POS1     ioaddr+1    /* Card-ID High (R) */
    144 #define SK_POS2     ioaddr+2    /* Card-Enable, Boot-ROM Disable (RW) */
    145 #define SK_POS3     ioaddr+3    /* Base address of RAM */
    146 #define SK_POS4     ioaddr+4    /* IRQ */
    147 
    148 /* POS5 - POS7 are unused */
    149 
    150 /*
    151  * SK_G16 MAC PREFIX
    152  * -----------------
    153  */
    154 
    155 /*
    156  * Scheider & Koch manufacturer code (00:00:a5).
    157  * This must be checked, that we are sure it is a SK card.
    158  */
    159 
    160 #define SK_MAC0         0x00
    161 #define SK_MAC1         0x00
    162 #define SK_MAC2         0x5a
    163 
    164 /*
    165  * SK_G16 ID
    166  * ---------
    167  */
    168 
    169 /*
    170  * If POS0,POS1 contain the following ID, then we know
    171  * at which I/O Port Address we are.
    172  */
    173 
    174 #define SK_IDLOW  0xfd
    175 #define SK_IDHIGH 0x6a
    176 
    177 
    178 /*
    179  * LANCE POS Bit definitions
    180  * -------------------------
    181  */
    182 
    183 #define SK_ROM_RAM_ON  (POS2_CARD)
    184 #define SK_ROM_RAM_OFF (POS2_EPROM)
    185 #define SK_ROM_ON      (inb(SK_POS2) & POS2_CARD)
    186 #define SK_ROM_OFF     (inb(SK_POS2) | POS2_EPROM)
    187 #define SK_RAM_ON      (inb(SK_POS2) | POS2_CARD)
    188 #define SK_RAM_OFF     (inb(SK_POS2) & POS2_EPROM)
    189 
    190 #define POS2_CARD  0x0001              /* 1 = SK_G16 on      0 = off */
    191 #define POS2_EPROM 0x0002              /* 1 = Boot EPROM off 0 = on */
    192 
    193 /*
    194  * SK_G16 Memory mapped Registers
    195  * ------------------------------
    196  *
    197  */
    198 
    199 #define SK_IOREG        (board->ioreg) /* LANCE data registers.     */
    200 #define SK_PORT         (board->port)  /* Control, Status register  */
    201 #define SK_IOCOM        (board->iocom) /* I/O Command               */
    202 
    203 /*
    204  * SK_G16 Status/Control Register bits
    205  * -----------------------------------
    206  *
    207  * (C) Controlreg (S) Statusreg
    208  */
    209 
    210 /*
    211  * Register transfer: 0 = no transfer
    212  *                    1 = transferring data between LANCE and I/O reg
    213  */
    214 #define SK_IORUN        0x20
    215 
    216 /*
    217  * LANCE interrupt: 0 = LANCE interrupt occurred
    218  *                  1 = no LANCE interrupt occurred
    219  */
    220 #define SK_IRQ          0x10
    221 
    222 #define SK_RESET        0x08   /* Reset SK_CARD: 0 = RESET 1 = normal */
    223 #define SK_RW           0x02   /* 0 = write to 1 = read from */
    224 #define SK_ADR          0x01   /* 0 = REG DataPort 1 = RAP Reg addr port */
    225 
    226 
    227 #define SK_RREG         SK_RW  /* Transferdirection to read from lance */
    228 #define SK_WREG         0      /* Transferdirection to write to lance */
    229 #define SK_RAP          SK_ADR /* Destination Register RAP */
    230 #define SK_RDATA        0      /* Destination Register REG DataPort */
    231 
    232 /*
    233  * SK_G16 I/O Command
    234  * ------------------
    235  */
    236 
    237 /*
    238  * Any bitcombination sets the internal I/O bit (transfer will start)
    239  * when written to I/O Command
    240  */
    241 
    242 #define SK_DOIO         0x80   /* Do Transfer */
    243 
    244 /*
    245  * LANCE RAP (Register Address Port).
    246  * ---------------------------------
    247  */
    248 
    249 /*
    250  * The LANCE internal registers are selected through the RAP.
    251  * The Registers are:
    252  *
    253  * CSR0 - Status and Control flags
    254  * CSR1 - Low order bits of initialize block (bits 15:00)
    255  * CSR2 - High order bits of initialize block (bits 07:00, 15:08 are reserved)
    256  * CSR3 - Allows redefinition of the Bus Master Interface.
    257  *        This register must be set to 0x0002, which means BSWAP = 0,
    258  *        ACON = 1, BCON = 0;
    259  *
    260  */
    261 
    262 #define CSR0            0x00
    263 #define CSR1            0x01
    264 #define CSR2            0x02
    265 #define CSR3            0x03
    266 
    267 /*
    268  * General Definitions
    269  * ===================
    270  */
    271 
    272 /*
    273  * Set the number of Tx and Rx buffers, using Log_2(# buffers).
    274  * We have 16KB RAM which can be accessed by the LANCE. In the
    275  * memory are not only the buffers but also the ring descriptors and
    276  * the initialize block.
    277  * Don't change anything unless you really know what you do.
    278  */
    279 
    280 #define LC_LOG_TX_BUFFERS 1               /* (2 == 2^^1) 2 Transmit buffers */
    281 #define LC_LOG_RX_BUFFERS 2               /* (8 == 2^^3) 8 Receive buffers */
    282 
    283 /* Descriptor ring sizes */
    284 
    285 #define TMDNUM (1 << (LC_LOG_TX_BUFFERS)) /* 2 Transmit descriptor rings */
    286 #define RMDNUM (1 << (LC_LOG_RX_BUFFERS)) /* 8 Receive Buffers */
    287 
    288 /* Define Mask for setting RMD, TMD length in the LANCE init_block */
    289 
    290 #define TMDNUMMASK (LC_LOG_TX_BUFFERS << 29)
    291 #define RMDNUMMASK (LC_LOG_RX_BUFFERS << 29)
    292 
    293 /*
    294  * Data Buffer size is set to maximum packet length.
    295  */
    296 
    297 #define PKT_BUF_SZ              1518
    298 
    299 /*
    300  * The number of low I/O ports used by the ethercard.
    301  */
    302 
    303 #define ETHERCARD_TOTAL_SIZE    SK_POS_SIZE
    304 
    305 /*
    306  * Portreserve is there to mark the Card I/O Port region as used.
    307  * Check_region is to check if the region at ioaddr with the size "size"
    308  * is free or not.
    309  * Snarf_region allocates the I/O Port region.
    310  */
    311 
    312 #ifndef	HAVE_PORTRESERVE
    313 
    314 #define check_region(ioaddr1, size)              0
    315 #define request_region(ioaddr1, size,name)       do ; while (0)
    316 
    317 #endif
    318 
    319 /*
    320  * SK_DEBUG
    321  *
    322  * Here you can choose what level of debugging wanted.
    323  *
    324  * If SK_DEBUG and SK_DEBUG2 are undefined, then only the
    325  *  necessary messages will be printed.
    326  *
    327  * If SK_DEBUG is defined, there will be many debugging prints
    328  *  which can help to find some mistakes in configuration or even
    329  *  in the driver code.
    330  *
    331  * If SK_DEBUG2 is defined, many many messages will be printed
    332  *  which normally you don't need. I used this to check the interrupt
    333  *  routine.
    334  *
    335  * (If you define only SK_DEBUG2 then only the messages for
    336  *  checking interrupts will be printed!)
    337  *
    338  * Normal way of live is:
    339  *
    340  * For the whole thing get going let both symbolic constants
    341  * undefined. If you face any problems and you know what's going
    342  * on (you know something about the card and you can interpret some
    343  * hex LANCE register output) then define SK_DEBUG
    344  *
    345  */
    346 
    347 #undef  SK_DEBUG	/* debugging */
    348 #undef  SK_DEBUG2	/* debugging with more verbose report */
    349 
    350 #ifdef	SK_DEBUG
    351 #define PRINTF(x) printf x
    352 #else
    353 #define PRINTF(x) /**/
    354 #endif
    355 
    356 #ifdef	SK_DEBUG2
    357 #define PRINTF2(x) printf x
    358 #else
    359 #define PRINTF2(x) /**/
    360 #endif
    361 
    362 /*
    363  * SK_G16 RAM
    364  *
    365  * The components are memory mapped and can be set in a region from
    366  * 0x00000 through 0xfc000 in 16KB steps.
    367  *
    368  * The Network components are: dual ported RAM, Prom, I/O Reg, Status-,
    369  * Controlregister and I/O Command.
    370  *
    371  * dual ported RAM: This is the only memory region which the LANCE chip
    372  *      has access to. From the Lance it is addressed from 0x0000 to
    373  *      0x3fbf. The host accesses it normally.
    374  *
    375  * PROM: The PROM obtains the ETHERNET-MAC-Address. It is realised as a
    376  *       8-Bit PROM, this means only the 16 even addresses are used of the
    377  *       32 Byte Address region. Access to a odd address results in invalid
    378  *       data.
    379  *
    380  * LANCE I/O Reg: The I/O Reg is build of 4 single Registers, Low-Byte Write,
    381  *       Hi-Byte Write, Low-Byte Read, Hi-Byte Read.
    382  *       Transfer from or to the LANCE is always in 16Bit so Low and High
    383  *       registers are always relevant.
    384  *
    385  *       The Data from the Readregister is not the data in the Writeregister!!
    386  *
    387  * Port: Status- and Controlregister.
    388  *       Two different registers which share the same address, Status is
    389  *       read-only, Control is write-only.
    390  *
    391  * I/O Command:
    392  *       Any bitcombination written in here starts the transmission between
    393  *       Host and LANCE.
    394  */
    395 
    396 typedef struct
    397 {
    398 	unsigned char  ram[0x3fc0];   /* 16KB dual ported ram */
    399 	unsigned char  rom[0x0020];   /* 32Byte PROM containing 6Byte MAC */
    400 	unsigned char  res1[0x0010];  /* reserved */
    401 	unsigned volatile short ioreg;/* LANCE I/O Register */
    402 	unsigned volatile char  port; /* Statusregister and Controlregister */
    403 	unsigned char  iocom;         /* I/O Command Register */
    404 } SK_RAM;
    405 
    406 /* struct  */
    407 
    408 /*
    409  * This is the structure for the dual ported ram. We
    410  * have exactly 16 320 Bytes. In here there must be:
    411  *
    412  *     - Initialize Block   (starting at a word boundary)
    413  *     - Receive and Transmit Descriptor Rings (quadword boundary)
    414  *     - Data Buffers (arbitrary boundary)
    415  *
    416  * This is because LANCE has on SK_G16 only access to the dual ported
    417  * RAM and nowhere else.
    418  */
    419 
    420 struct SK_ram
    421 {
    422     struct init_block ib;
    423     struct tmd tmde[TMDNUM];
    424     struct rmd rmde[RMDNUM];
    425     char tmdbuf[TMDNUM][PKT_BUF_SZ];
    426     char rmdbuf[RMDNUM][PKT_BUF_SZ];
    427 };
    428 
    429 /*
    430  * Structure where all necessary information is for ring buffer
    431  * management and statistics.
    432  */
    433 
    434 struct priv
    435 {
    436     struct SK_ram *ram;  /* dual ported ram structure */
    437     struct rmd *rmdhead; /* start of receive ring descriptors */
    438     struct tmd *tmdhead; /* start of transmit ring descriptors */
    439     int        rmdnum;   /* actual used ring descriptor */
    440     int        tmdnum;   /* actual transmit descriptor for transmitting data */
    441     int        tmdlast;  /* last sent descriptor used for error handling, etc */
    442     void       *rmdbufs[RMDNUM]; /* pointer to the receive buffers */
    443     void       *tmdbufs[TMDNUM]; /* pointer to the transmit buffers */
    444 };
    445 
    446 /* global variable declaration */
    447 
    448 /* static variables */
    449 
    450 static SK_RAM *board;  /* pointer to our memory mapped board components */
    451 static unsigned short	ioaddr; /* base io address */
    452 static struct priv	p_data;
    453 
    454 /* Macros */
    455 
    456 
    457 /* Function Prototypes */
    458 
    459 /*
    460  * Device Driver functions
    461  * -----------------------
    462  * See for short explanation of each function its definitions header.
    463  */
    464 
    465 static int   SK_probe1(struct nic *nic, short ioaddr1);
    466 
    467 static void SK_reset(struct nic *nic);
    468 static int SK_poll(struct nic *nic);
    469 static void SK_transmit(
    470 struct nic *nic,
    471 const char *d,			/* Destination */
    472 unsigned int t,			/* Type */
    473 unsigned int s,			/* size */
    474 const char *p);			/* Packet */
    475 static void SK_disable(struct nic *nic);
    476 struct nic *SK_probe(struct nic *nic, unsigned short *probe_addrs);
    477 
    478 /*
    479  * LANCE Functions
    480  * ---------------
    481  */
    482 
    483 static int SK_lance_init(struct nic *nic, unsigned short mode);
    484 static void SK_reset_board(void);
    485 static void SK_set_RAP(int reg_number);
    486 static int SK_read_reg(int reg_number);
    487 static int SK_rread_reg(void);
    488 static void SK_write_reg(int reg_number, int value);
    489 
    490 /*
    491  * Debugging functions
    492  * -------------------
    493  */
    494 
    495 static void SK_print_pos(struct nic *nic, char *text);
    496 static void SK_print_ram(struct nic *nic);
    497 
    498 
    499 /**************************************************************************
    500 RESET - Reset adapter
    501 ***************************************************************************/
    502 static void SK_reset(struct nic *nic)
    503 {
    504 	/* put the card in its initial state */
    505 	SK_lance_init(nic, MODE_NORMAL);
    506 }
    507 
    508 /**************************************************************************
    509 POLL - Wait for a frame
    510 ***************************************************************************/
    511 static int SK_poll(struct nic *nic)
    512 {
    513 	/* return true if there's an ethernet packet ready to read */
    514 	struct priv *p;         /* SK_G16 private structure */
    515 	struct rmd *rmdp;
    516 	int csr0, rmdstat, packet_there;
    517     PRINTF2(("## %s: At beginning of SK_poll(). CSR0: %#hX\n",
    518            SK_NAME, SK_read_reg(CSR0)));
    519 
    520 	p = nic->priv_data;
    521     csr0 = SK_read_reg(CSR0);      /* store register for checking */
    522 
    523     /*
    524      * Acknowledge all of the current interrupt sources, disable
    525      * Interrupts (INEA = 0)
    526      */
    527 
    528     SK_write_reg(CSR0, csr0 & CSR0_CLRALL);
    529 
    530     if (csr0 & CSR0_ERR) /* LANCE Error */
    531     {
    532 	printf("%s: error: %#hX", SK_NAME, csr0);
    533 
    534         if (csr0 & CSR0_MISS)      /* No place to store packet ? */
    535         {
    536 		printf(", Packet dropped.");
    537         }
    538 	putchar('\n');
    539     }
    540 
    541     rmdp = p->rmdhead + p->rmdnum;
    542     packet_there = 0;
    543     /* As long as we own the next entry, check status and send
    544      * it up to higher layer
    545      */
    546 
    547     while (!( (rmdstat = rmdp->u.s.status) & RX_OWN))
    548     {
    549 	/*
    550          * Start and end of packet must be set, because we use
    551 	 * the ethernet maximum packet length (1518) as buffer size.
    552 	 *
    553 	 * Because our buffers are at maximum OFLO and BUFF errors are
    554 	 * not to be concerned (see Data sheet)
    555 	 */
    556 
    557 	if ((rmdstat & (RX_STP | RX_ENP)) != (RX_STP | RX_ENP))
    558 	{
    559 	    /* Start of a frame > 1518 Bytes ? */
    560 
    561 	    if (rmdstat & RX_STP)
    562 	    {
    563 		printf("%s: packet too long\n", SK_NAME);
    564 	    }
    565 
    566 	    /*
    567              * All other packets will be ignored until a new frame with
    568 	     * start (RX_STP) set follows.
    569 	     *
    570 	     * What we do is just give descriptor free for new incoming
    571 	     * packets.
    572 	     */
    573 
    574 	    rmdp->u.s.status = RX_OWN;      /* Relinquish ownership to LANCE */
    575 
    576 	}
    577 	else if (rmdstat & RX_ERR)          /* Receive Error ? */
    578 	{
    579 	    printf("%s: RX error: %#hX\n", SK_NAME, (int) rmdstat);
    580 	    rmdp->u.s.status = RX_OWN;      /* Relinquish ownership to LANCE */
    581 	}
    582 	else /* We have a packet which can be queued for the upper layers */
    583 	{
    584 
    585 	    int len = (rmdp->mlen & 0x0fff);  /* extract message length from receive buffer */
    586 
    587 	    /*
    588              * Copy data out of our receive descriptor into nic->packet.
    589 	     *
    590 	     * (rmdp->u.buffer & 0x00ffffff) -> get address of buffer and
    591 	     * ignore status fields)
    592 	     */
    593 
    594 	    memcpy(nic->packet, (unsigned char *) (rmdp->u.buffer & 0x00ffffff), nic->packetlen = len);
    595 	    packet_there = 1;
    596 
    597 
    598 	    /*
    599              * Packet is queued and marked for processing so we
    600 	     * free our descriptor
    601 	     */
    602 
    603 	    rmdp->u.s.status = RX_OWN;
    604 
    605 	    p->rmdnum++;
    606 	    p->rmdnum %= RMDNUM;
    607 
    608 	    rmdp = p->rmdhead + p->rmdnum;
    609 	}
    610     }
    611     SK_write_reg(CSR0, CSR0_INEA); /* Enable Interrupts */
    612 	return (packet_there);
    613 }
    614 
    615 /**************************************************************************
    616 TRANSMIT - Transmit a frame
    617 ***************************************************************************/
    618 static void SK_transmit(
    619 struct nic *nic,
    620 const char *d,			/* Destination */
    621 unsigned int t,			/* Type */
    622 unsigned int s,			/* size */
    623 const char *pack)		/* Packet */
    624 {
    625 	/* send the packet to destination */
    626     struct priv *p;         /* SK_G16 private structure */
    627     struct tmd *tmdp;
    628     short len;
    629     int csr0, i, tmdstat;
    630 
    631     PRINTF2(("## %s: At beginning of SK_transmit(). CSR0: %#hX\n",
    632            SK_NAME, SK_read_reg(CSR0)));
    633 	p = nic->priv_data;
    634 	tmdp = p->tmdhead + p->tmdnum; /* Which descriptor for transmitting */
    635 
    636 	/* Copy data into dual ported ram */
    637 
    638 	memcpy(&p->ram->tmdbuf[p->tmdnum][0], d, ETH_ALEN);	/* dst */
    639 	memcpy(&p->ram->tmdbuf[p->tmdnum][ETH_ALEN], nic->node_addr, ETH_ALEN); /* src */
    640 	p->ram->tmdbuf[p->tmdnum][ETH_ALEN + ETH_ALEN] = t >> 8;	/* type */
    641 	p->ram->tmdbuf[p->tmdnum][ETH_ALEN + ETH_ALEN + 1] = t;	/* type */
    642 	memcpy(&p->ram->tmdbuf[p->tmdnum][ETH_HLEN], pack, s);
    643 	s += ETH_HLEN;
    644 	while (s < ETH_ZLEN)	/* pad to min length */
    645 		p->ram->tmdbuf[p->tmdnum][s++] = 0;
    646 	p->ram->tmde[p->tmdnum].status2 = 0x0;
    647 
    648 	/* Evaluate Packet length */
    649 	len = ETH_ZLEN < s ? s : ETH_ZLEN;
    650 
    651 	/* Fill in Transmit Message Descriptor */
    652 
    653 	tmdp->blen = -len;            /* set length to transmit */
    654 
    655 	/*
    656 	 * Packet start and end is always set because we use the maximum
    657 	 * packet length as buffer length.
    658 	 * Relinquish ownership to LANCE
    659 	 */
    660 
    661 	tmdp->u.s.status = TX_OWN | TX_STP | TX_ENP;
    662 
    663 	/* Start Demand Transmission */
    664 	SK_write_reg(CSR0, CSR0_TDMD | CSR0_INEA);
    665 
    666     csr0 = SK_read_reg(CSR0);      /* store register for checking */
    667 
    668     /*
    669      * Acknowledge all of the current interrupt sources, disable
    670      * Interrupts (INEA = 0)
    671      */
    672 
    673     SK_write_reg(CSR0, csr0 & CSR0_CLRALL);
    674 
    675     if (csr0 & CSR0_ERR) /* LANCE Error */
    676     {
    677 	printf("%s: error: %#hX", SK_NAME, csr0);
    678 
    679         if (csr0 & CSR0_MISS)      /* No place to store packet ? */
    680         {
    681 		printf(", Packet dropped.");
    682         }
    683 	putchar('\n');
    684     }
    685 
    686 
    687     /* Set next buffer */
    688     p->tmdlast++;
    689     p->tmdlast &= TMDNUM-1;
    690 
    691     tmdstat = tmdp->u.s.status & 0xff00; /* filter out status bits 15:08 */
    692 
    693     /*
    694      * We check status of transmitted packet.
    695      * see LANCE data-sheet for error explanation
    696      */
    697     if (tmdstat & TX_ERR) /* Error occurred */
    698     {
    699 	printf("%s: TX error: %#hX %#hX\n", SK_NAME, (int) tmdstat,
    700 		(int) tmdp->status2);
    701 
    702 	if (tmdp->status2 & TX_TDR)    /* TDR problems? */
    703 	{
    704 	    printf("%s: tdr-problems \n", SK_NAME);
    705 	}
    706 
    707         if (tmdp->status2 & TX_UFLO)   /* Underflow error ? */
    708         {
    709             /*
    710              * If UFLO error occurs it will turn transmitter of.
    711              * So we must reinit LANCE
    712              */
    713 
    714             SK_lance_init(nic, MODE_NORMAL);
    715         }
    716 
    717 	tmdp->status2 = 0;             /* Clear error flags */
    718     }
    719 
    720     SK_write_reg(CSR0, CSR0_INEA); /* Enable Interrupts */
    721 
    722 	/* Set pointer to next transmit buffer */
    723 	p->tmdnum++;
    724 	p->tmdnum &= TMDNUM-1;
    725 
    726 }
    727 
    728 /**************************************************************************
    729 DISABLE - Turn off ethernet interface
    730 ***************************************************************************/
    731 static void SK_disable(struct nic *nic)
    732 {
    733     PRINTF(("## %s: At beginning of SK_disable(). CSR0: %#hX\n",
    734            SK_NAME, SK_read_reg(CSR0)));
    735     PRINTF(("%s: Shutting %s down CSR0 %#hX\n", SK_NAME, SK_NAME,
    736            (int) SK_read_reg(CSR0)));
    737 
    738     SK_write_reg(CSR0, CSR0_STOP); /* STOP the LANCE */
    739 }
    740 
    741 /**************************************************************************
    742 PROBE - Look for an adapter, this routine's visible to the outside
    743 ***************************************************************************/
    744 struct nic *SK_probe(struct nic *nic, unsigned short *probe_addrs)
    745 {
    746 	unsigned short		*p;
    747 	static unsigned short	io_addrs[] = SK_IO_PORTS;
    748 	/* if probe_addrs is 0, then routine can use a hardwired default */
    749 	putchar('\n');
    750 	nic->priv_data = &p_data;
    751 	if (probe_addrs == 0)
    752 		probe_addrs = io_addrs;
    753 	for (p = probe_addrs; (ioaddr = *p) != 0; ++p)
    754 	{
    755 		long		offset1, offset0 = inb(ioaddr);
    756 		if ((offset0 == SK_IDLOW) &&
    757 		 ((offset1 = inb(ioaddr + 1)) == SK_IDHIGH))
    758 			if (SK_probe1(nic, ioaddr) >= 0)
    759 				break;
    760 	}
    761 	/* if board found */
    762 	if (ioaddr != 0)
    763 	{
    764 		/* point to NIC specific routines */
    765 		nic->reset = SK_reset;
    766 		nic->poll = SK_poll;
    767 		nic->transmit = SK_transmit;
    768 		nic->disable = SK_disable;
    769 		return nic;
    770 	}
    771 	/* else */
    772 	{
    773 		return 0;
    774 	}
    775 }
    776 
    777 int SK_probe1(struct nic *nic, short ioaddr1)
    778 {
    779     int i,j;                /* Counters */
    780     int sk_addr_flag = 0;   /* SK ADDR correct? 1 - no, 0 - yes */
    781     unsigned int rom_addr;  /* used to store RAM address used for POS_ADDR */
    782 
    783     struct priv *p;         /* SK_G16 private structure */
    784 
    785     if (SK_ADDR & 0x3fff || SK_ADDR < 0xa0000)
    786     {
    787        /*
    788         * Now here we could use a routine which searches for a free
    789         * place in the ram and set SK_ADDR if found. TODO.
    790         */
    791             printf("%s: SK_ADDR %#hX is not valid. Check configuration.\n",
    792                     SK_NAME, SK_ADDR);
    793             return -1;
    794     }
    795 
    796     rom_addr = SK_ADDR;
    797 
    798     outb(SK_ROM_RAM_OFF, SK_POS2); /* Boot_ROM + RAM off */
    799     outb(POS_ADDR, SK_POS3);       /* Set RAM address */
    800     outb(SK_ROM_RAM_ON, SK_POS2);  /* RAM on, BOOT_ROM on */
    801 #ifdef	SK_DEBUG
    802     SK_print_pos(nic, "POS registers after ROM, RAM config");
    803 #endif
    804 
    805     board = (SK_RAM *) rom_addr;
    806 	PRINTF(("adr[0]: %hX, adr[1]: %hX, adr[2]: %hX\n",
    807 	board->rom[0], board->rom[2], board->rom[4]));
    808 
    809     /* Read in station address */
    810     for (i = 0, j = 0; i < ETH_ALEN; i++, j+=2)
    811     {
    812 	*(nic->node_addr+i) = board->rom[j];
    813     }
    814 
    815     /* Check for manufacturer code */
    816 #ifdef	SK_DEBUG
    817     if (!(*(nic->node_addr+0) == SK_MAC0 &&
    818 	  *(nic->node_addr+1) == SK_MAC1 &&
    819 	  *(nic->node_addr+2) == SK_MAC2) )
    820     {
    821         PRINTF(("## %s: We did not find SK_G16 at RAM location.\n",
    822                 SK_NAME));
    823 	return -1;                     /* NO SK_G16 found */
    824     }
    825 #endif
    826 
    827     p = nic->priv_data;
    828 
    829     /* Initialize private structure */
    830 
    831     p->ram = (struct SK_ram *) rom_addr; /* Set dual ported RAM addr */
    832     p->tmdhead = &(p->ram)->tmde[0];     /* Set TMD head */
    833     p->rmdhead = &(p->ram)->rmde[0];     /* Set RMD head */
    834 
    835     printf("Schneider & Koch G16 at %#hX, mem at %#hX, HW addr: %!\n",
    836 	    (unsigned int) ioaddr, (unsigned int) p->ram, nic->node_addr);
    837 
    838     /* Initialize buffer pointers */
    839 
    840     for (i = 0; i < TMDNUM; i++)
    841     {
    842 	p->tmdbufs[i] = p->ram->tmdbuf[i];
    843     }
    844 
    845     for (i = 0; i < RMDNUM; i++)
    846     {
    847 	p->rmdbufs[i] = p->ram->rmdbuf[i];
    848     }
    849     i = 0;
    850 
    851     if (!(i = SK_lance_init(nic, MODE_NORMAL)))  /* LANCE init OK? */
    852     {
    853 
    854 #ifdef	SK_DEBUG
    855         /*
    856          * This debug block tries to stop LANCE,
    857          * reinit LANCE with transmitter and receiver disabled,
    858          * then stop again and reinit with NORMAL_MODE
    859          */
    860 
    861         printf("## %s: After lance init. CSR0: %#hX\n",
    862                SK_NAME, SK_read_reg(CSR0));
    863         SK_write_reg(CSR0, CSR0_STOP);
    864         printf("## %s: LANCE stopped. CSR0: %#hX\n",
    865                SK_NAME, SK_read_reg(CSR0));
    866         SK_lance_init(nic, MODE_DTX | MODE_DRX);
    867         printf("## %s: Reinit with DTX + DRX off. CSR0: %#hX\n",
    868                SK_NAME, SK_read_reg(CSR0));
    869         SK_write_reg(CSR0, CSR0_STOP);
    870         printf("## %s: LANCE stopped. CSR0: %#hX\n",
    871                SK_NAME, SK_read_reg(CSR0));
    872         SK_lance_init(nic, MODE_NORMAL);
    873         printf("## %s: LANCE back to normal mode. CSR0: %#hX\n",
    874                SK_NAME, SK_read_reg(CSR0));
    875         SK_print_pos(nic, "POS regs before returning OK");
    876 
    877 #endif	/* SK_DEBUG */
    878 
    879     }
    880     else /* LANCE init failed */
    881     {
    882 
    883 	PRINTF(("## %s: LANCE init failed: CSR0: %#hX\n",
    884                SK_NAME, SK_read_reg(CSR0)));
    885 	return -1;
    886     }
    887 
    888 #ifdef	SK_DEBUG
    889     SK_print_pos(nic, "End of SK_probe1");
    890     SK_print_ram(nic);
    891 #endif
    892 
    893     return 0;                            /* Initialization done */
    894 
    895 } /* End of SK_probe1() */
    896 
    897 static int SK_lance_init(struct nic *nic, unsigned short mode)
    898 {
    899     int i;
    900     struct priv *p = (struct priv *) nic->priv_data;
    901     struct tmd  *tmdp;
    902     struct rmd  *rmdp;
    903 
    904     PRINTF(("## %s: At beginning of LANCE init. CSR0: %#hX\n",
    905            SK_NAME, SK_read_reg(CSR0)));
    906 
    907     /* Reset LANCE */
    908     SK_reset_board();
    909 
    910     /* Initialize TMD's with start values */
    911     p->tmdnum = 0;                   /* First descriptor for transmitting */
    912     p->tmdlast = 0;                  /* First descriptor for reading stats */
    913 
    914     for (i = 0; i < TMDNUM; i++)     /* Init all TMD's */
    915     {
    916 	tmdp = p->tmdhead + i;
    917 
    918 	tmdp->u.buffer = (unsigned long) p->tmdbufs[i]; /* assign buffer */
    919 
    920 	/* Mark TMD as start and end of packet */
    921 	tmdp->u.s.status = TX_STP | TX_ENP;
    922     }
    923 
    924 
    925     /* Initialize RMD's with start values */
    926 
    927     p->rmdnum = 0;                   /* First RMD which will be used */
    928 
    929     for (i = 0; i < RMDNUM; i++)     /* Init all RMD's */
    930     {
    931 	rmdp = p->rmdhead + i;
    932 
    933 
    934 	rmdp->u.buffer = (unsigned long) p->rmdbufs[i]; /* assign buffer */
    935 
    936 	/*
    937          * LANCE must be owner at beginning so that he can fill in
    938 	 * receiving packets, set status and release RMD
    939 	 */
    940 
    941 	rmdp->u.s.status = RX_OWN;
    942 
    943 	rmdp->blen = -PKT_BUF_SZ;    /* Buffer Size in a two's complement */
    944 
    945 	rmdp->mlen = 0;              /* init message length */
    946 
    947     }
    948 
    949     /* Fill LANCE Initialize Block */
    950 
    951     (p->ram)->ib.mode = mode;        /* Set operation mode */
    952 
    953     for (i = 0; i < ETH_ALEN; i++)   /* Set physical address */
    954     {
    955 	(p->ram)->ib.paddr[i] = *(nic->node_addr+i);
    956     }
    957 
    958     for (i = 0; i < 8; i++)          /* Set multicast, logical address */
    959     {
    960 	(p->ram)->ib.laddr[i] = 0;   /* We do not use logical addressing */
    961     }
    962 
    963     /* Set ring descriptor pointers and set number of descriptors */
    964 
    965     (p->ram)->ib.rdrp = (int)  p->rmdhead | RMDNUMMASK;
    966     (p->ram)->ib.tdrp = (int)  p->tmdhead | TMDNUMMASK;
    967 
    968     /* Prepare LANCE Control and Status Registers */
    969 
    970     SK_write_reg(CSR3, CSR3_ACON);   /* Ale Control !!!THIS MUST BE SET!!!! */
    971 
    972     /*
    973      * LANCE addresses the RAM from 0x0000 to 0x3fbf and has no access to
    974      * PC Memory locations.
    975      *
    976      * In structure SK_ram is defined that the first thing in ram
    977      * is the initialization block. So his address is for LANCE always
    978      * 0x0000
    979      *
    980      * CSR1 contains low order bits 15:0 of initialization block address
    981      * CSR2 is built of:
    982      *    7:0  High order bits 23:16 of initialization block address
    983      *   15:8  reserved, must be 0
    984      */
    985 
    986     /* Set initialization block address (must be on word boundary) */
    987     SK_write_reg(CSR1, 0);          /* Set low order bits 15:0 */
    988     SK_write_reg(CSR2, 0);          /* Set high order bits 23:16 */
    989 
    990 
    991     PRINTF(("## %s: After setting CSR1-3. CSR0: %#hX\n",
    992            SK_NAME, SK_read_reg(CSR0)));
    993 
    994     /* Initialize LANCE */
    995 
    996     /*
    997      * INIT = Initialize, when set, causes the LANCE to begin the
    998      * initialization procedure and access the Init Block.
    999      */
   1000 
   1001     SK_write_reg(CSR0, CSR0_INIT);
   1002 
   1003     /* Wait until LANCE finished initialization */
   1004 
   1005     SK_set_RAP(CSR0);              /* Register Address Pointer to CSR0 */
   1006 
   1007     for (i = 0; (i < 100) && !(SK_rread_reg() & CSR0_IDON); i++)
   1008 	; /* Wait until init done or go ahead if problems (i>=100) */
   1009 
   1010     if (i >= 100) /* Something is wrong ! */
   1011     {
   1012 	printf("%s: can't init am7990, status: %#hX "
   1013 	       "init_block: %#hX\n",
   1014 		SK_NAME, (int) SK_read_reg(CSR0),
   1015 		(unsigned int) &(p->ram)->ib);
   1016 
   1017 #ifdef	SK_DEBUG
   1018 	SK_print_pos(nic, "LANCE INIT failed");
   1019 #endif
   1020 
   1021 	return -1;                 /* LANCE init failed */
   1022     }
   1023 
   1024     PRINTF(("## %s: init done after %d ticks\n", SK_NAME, i));
   1025 
   1026     /* Clear Initialize done, enable Interrupts, start LANCE */
   1027 
   1028     SK_write_reg(CSR0, CSR0_IDON | CSR0_INEA | CSR0_STRT);
   1029 
   1030     PRINTF(("## %s: LANCE started. CSR0: %#hX\n", SK_NAME,
   1031             SK_read_reg(CSR0)));
   1032 
   1033     return 0;                      /* LANCE is up and running */
   1034 
   1035 } /* End of SK_lance_init() */
   1036 
   1037 /* LANCE access functions
   1038  *
   1039  * ! CSR1-3 can only be accessed when in CSR0 the STOP bit is set !
   1040  */
   1041 
   1042 static void SK_reset_board(void)
   1043 {
   1044     int i;
   1045 
   1046 	PRINTF(("## %s: At beginning of SK_reset_board.\n", SK_NAME));
   1047     SK_PORT = 0x00;           /* Reset active */
   1048     for (i = 0; i < 10 ; i++) /* Delay min 5ms */
   1049 	;
   1050     SK_PORT = SK_RESET;       /* Set back to normal operation */
   1051 
   1052 } /* End of SK_reset_board() */
   1053 
   1054 static void SK_set_RAP(int reg_number)
   1055 {
   1056     SK_IOREG = reg_number;
   1057     SK_PORT  = SK_RESET | SK_RAP | SK_WREG;
   1058     SK_IOCOM = SK_DOIO;
   1059 
   1060     while (SK_PORT & SK_IORUN)
   1061 	;
   1062 } /* End of SK_set_RAP() */
   1063 
   1064 static int SK_read_reg(int reg_number)
   1065 {
   1066     SK_set_RAP(reg_number);
   1067 
   1068     SK_PORT  = SK_RESET | SK_RDATA | SK_RREG;
   1069     SK_IOCOM = SK_DOIO;
   1070 
   1071     while (SK_PORT & SK_IORUN)
   1072 	;
   1073     return (SK_IOREG);
   1074 
   1075 } /* End of SK_read_reg() */
   1076 
   1077 static int SK_rread_reg(void)
   1078 {
   1079     SK_PORT  = SK_RESET | SK_RDATA | SK_RREG;
   1080 
   1081     SK_IOCOM = SK_DOIO;
   1082 
   1083     while (SK_PORT & SK_IORUN)
   1084 	;
   1085     return (SK_IOREG);
   1086 
   1087 } /* End of SK_rread_reg() */
   1088 
   1089 static void SK_write_reg(int reg_number, int value)
   1090 {
   1091     SK_set_RAP(reg_number);
   1092 
   1093     SK_IOREG = value;
   1094     SK_PORT  = SK_RESET | SK_RDATA | SK_WREG;
   1095     SK_IOCOM = SK_DOIO;
   1096 
   1097     while (SK_PORT & SK_IORUN)
   1098 	;
   1099 } /* End of SK_write_reg */
   1100 
   1101 /*
   1102  * Debugging functions
   1103  * -------------------
   1104  */
   1105 
   1106 #ifdef	SK_DEBUG
   1107 static void SK_print_pos(struct nic *nic, char *text)
   1108 {
   1109 
   1110     unsigned char pos0 = inb(SK_POS0),
   1111 		  pos1 = inb(SK_POS1),
   1112 		  pos2 = inb(SK_POS2),
   1113 		  pos3 = inb(SK_POS3),
   1114 		  pos4 = inb(SK_POS4);
   1115 
   1116 
   1117     printf("## %s: %s.\n"
   1118            "##   pos0=%#hX pos1=%#hX pos2=%#hX pos3=%#hX pos4=%#hX\n",
   1119            SK_NAME, text, pos0, pos1, pos2, (pos3<<14), pos4);
   1120 
   1121 } /* End of SK_print_pos() */
   1122 
   1123 static void SK_print_ram(struct nic *nic)
   1124 {
   1125 
   1126     int i;
   1127     struct priv *p = (struct priv *) nic->priv_data;
   1128 
   1129     printf("## %s: RAM Details.\n"
   1130            "##   RAM at %#hX tmdhead: %#hX rmdhead: %#hX initblock: %#hX\n",
   1131            SK_NAME,
   1132            (unsigned int) p->ram,
   1133            (unsigned int) p->tmdhead,
   1134            (unsigned int) p->rmdhead,
   1135            (unsigned int) &(p->ram)->ib);
   1136 
   1137     printf("##   ");
   1138 
   1139     for(i = 0; i < TMDNUM; i++)
   1140     {
   1141            if (!(i % 3)) /* Every third line do a newline */
   1142            {
   1143                printf("\n##   ");
   1144            }
   1145         printf("tmdbufs%d: %#hX ", (i+1), (int) p->tmdbufs[i]);
   1146     }
   1147     printf("##   ");
   1148 
   1149     for(i = 0; i < RMDNUM; i++)
   1150     {
   1151          if (!(i % 3)) /* Every third line do a newline */
   1152            {
   1153                printf("\n##   ");
   1154            }
   1155         printf("rmdbufs%d: %#hX ", (i+1), (int) p->rmdbufs[i]);
   1156     }
   1157     putchar('\n');
   1158 
   1159 } /* End of SK_print_ram() */
   1160 #endif
   1161