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if_ie_vme.c revision 1.16
      1 /*	$NetBSD: if_ie_vme.c,v 1.16 2002/10/01 01:28:03 thorpej Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1995 Charles D. Cranor
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *      This product includes software developed by Charles D. Cranor.
     18  * 4. The name of the author may not be used to endorse or promote products
     19  *    derived from this software without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     31  */
     32 
     33 /*
     34  * Converted to SUN ie driver by Charles D. Cranor,
     35  *		October 1994, January 1995.
     36  */
     37 
     38 /*
     39  * The i82586 is a very painful chip, found in sun3's, sun-4/100's
     40  * sun-4/200's, and VME based suns.  The byte order is all wrong for a
     41  * SUN, making life difficult.  Programming this chip is mostly the same,
     42  * but certain details differ from system to system.  This driver is
     43  * written so that different "ie" interfaces can be controled by the same
     44  * driver.
     45  */
     46 
     47 /*
     48  * programming notes:
     49  *
     50  * the ie chip operates in a 24 bit address space.
     51  *
     52  * most ie interfaces appear to be divided into two parts:
     53  *	 - generic 586 stuff
     54  *	 - board specific
     55  *
     56  * generic:
     57  *	the generic stuff of the ie chip is all done with data structures
     58  * 	that live in the chip's memory address space.   the chip expects
     59  * 	its main data structure (the sys conf ptr -- SCP) to be at a fixed
     60  * 	address in its 24 bit space: 0xfffff4
     61  *
     62  *      the SCP points to another structure called the ISCP.
     63  *      the ISCP points to another structure called the SCB.
     64  * 	the SCB has a status field, a linked list of "commands", and
     65  * 	a linked list of "receive buffers".   these are data structures that
     66  * 	live in memory, not registers.
     67  *
     68  * board:
     69  * 	to get the chip to do anything, you first put a command in the
     70  * 	command data structure list.   then you have to signal "attention"
     71  * 	to the chip to get it to look at the command.   how you
     72  * 	signal attention depends on what board you have... on PC's
     73  * 	there is an i/o port number to do this, on sun's there is a
     74  * 	register bit you toggle.
     75  *
     76  * 	to get data from the chip you program it to interrupt...
     77  *
     78  *
     79  * sun issues:
     80  *
     81  *      there are 3 kinds of sun "ie" interfaces:
     82  *        1 - a VME/multibus card
     83  *        2 - an on-board interface (sun3's, sun-4/100's, and sun-4/200's)
     84  *        3 - another VME board called the 3E
     85  *
     86  * 	the VME boards lives in vme16 space.   only 16 and 8 bit accesses
     87  * 	are allowed, so functions that copy data must be aware of this.
     88  *
     89  * 	the chip is an intel chip.  this means that the byte order
     90  * 	on all the "short"s in the chip's data structures is wrong.
     91  * 	so, constants described in the intel docs are swapped for the sun.
     92  * 	that means that any buffer pointers you give the chip must be
     93  * 	swapped to intel format.   yuck.
     94  *
     95  *   VME/multibus interface:
     96  * 	for the multibus interface the board ignores the top 4 bits
     97  * 	of the chip address.   the multibus interface has its own
     98  * 	MMU like page map (without protections or valid bits, etc).
     99  * 	there are 256 pages of physical memory on the board (each page
    100  * 	is 1024 bytes).   There are 1024 slots in the page map.  so,
    101  * 	a 1024 byte page takes up 10 bits of address for the offset,
    102  * 	and if there are 1024 slots in the page that is another 10 bits
    103  * 	of the address.   That makes a 20 bit address, and as stated
    104  * 	earlier the board ignores the top 4 bits, so that accounts
    105  * 	for all 24 bits of address.
    106  *
    107  * 	Note that the last entry of the page map maps the top of the
    108  * 	24 bit address space and that the SCP is supposed to be at
    109  * 	0xfffff4 (taking into account allignment).   so,
    110  *	for multibus, that entry in the page map has to be used for the SCP.
    111  *
    112  * 	The page map effects BOTH how the ie chip sees the
    113  * 	memory, and how the host sees it.
    114  *
    115  * 	The page map is part of the "register" area of the board
    116  *
    117  *	The page map to control where ram appears in the address space.
    118  *	We choose to have RAM start at 0 in the 24 bit address space.
    119  *
    120  *	to get the phyiscal address of the board's RAM you must take the
    121  *	top 12 bits of the physical address of the register address and
    122  *	or in the 4 bits from the status word as bits 17-20 (remember that
    123  *	the board ignores the chip's top 4 address lines). For example:
    124  *	if the register is @ 0xffe88000, then the top 12 bits are 0xffe00000.
    125  *	to get the 4 bits from the status word just do status & IEVME_HADDR.
    126  *	suppose the value is "4".   Then just shift it left 16 bits to get
    127  *	it into bits 17-20 (e.g. 0x40000).    Then or it to get the
    128  *	address of RAM (in our example: 0xffe40000).   see the attach routine!
    129  *
    130  *
    131  *   on-board interface:
    132  *
    133  *	on the onboard ie interface the 24 bit address space is hardwired
    134  *	to be 0xff000000 -> 0xffffffff of KVA.   this means that sc_iobase
    135  *	will be 0xff000000.   sc_maddr will be where ever we allocate RAM
    136  *	in KVA.    note that since the SCP is at a fixed address it means
    137  *	that we have to allocate a fixed KVA for the SCP.
    138  *	<fill in useful info later>
    139  *
    140  *
    141  *   VME3E interface:
    142  *
    143  *	<fill in useful info later>
    144  *
    145  */
    146 
    147 #include <sys/cdefs.h>
    148 __KERNEL_RCSID(0, "$NetBSD: if_ie_vme.c,v 1.16 2002/10/01 01:28:03 thorpej Exp $");
    149 
    150 #include <sys/param.h>
    151 #include <sys/systm.h>
    152 #include <sys/errno.h>
    153 #include <sys/device.h>
    154 #include <sys/protosw.h>
    155 #include <sys/socket.h>
    156 
    157 #include <net/if.h>
    158 #include <net/if_types.h>
    159 #include <net/if_dl.h>
    160 #include <net/if_media.h>
    161 #include <net/if_ether.h>
    162 
    163 #include <machine/bus.h>
    164 #include <machine/intr.h>
    165 #include <dev/vme/vmevar.h>
    166 
    167 #include <dev/ic/i82586reg.h>
    168 #include <dev/ic/i82586var.h>
    169 
    170 #include "locators.h"
    171 
    172 /*
    173  * VME/multibus definitions
    174  */
    175 #define IEVME_PAGESIZE 1024	/* bytes */
    176 #define IEVME_PAGSHIFT 10	/* bits */
    177 #define IEVME_NPAGES   256	/* number of pages on chip */
    178 #define IEVME_MAPSZ    1024	/* number of entries in the map */
    179 
    180 /*
    181  * PTE for the page map
    182  */
    183 #define IEVME_SBORDR 0x8000	/* sun byte order */
    184 #define IEVME_IBORDR 0x0000	/* intel byte ordr */
    185 
    186 #define IEVME_P2MEM  0x2000	/* memory is on P2 */
    187 #define IEVME_OBMEM  0x0000	/* memory is on board */
    188 
    189 #define IEVME_PGMASK 0x0fff	/* gives the physical page frame number */
    190 
    191 struct ievme {
    192 	u_int16_t	pgmap[IEVME_MAPSZ];
    193 	u_int16_t	xxx[32];	/* prom */
    194 	u_int16_t	status;		/* see below for bits */
    195 	u_int16_t	xxx2;		/* filler */
    196 	u_int16_t	pectrl;		/* parity control (see below) */
    197 	u_int16_t	peaddr;		/* low 16 bits of address */
    198 };
    199 
    200 /*
    201  * status bits
    202  */
    203 #define IEVME_RESET 0x8000	/* reset board */
    204 #define IEVME_ONAIR 0x4000	/* go out of loopback 'on-air' */
    205 #define IEVME_ATTEN 0x2000	/* attention */
    206 #define IEVME_IENAB 0x1000	/* interrupt enable */
    207 #define IEVME_PEINT 0x0800	/* parity error interrupt enable */
    208 #define IEVME_PERR  0x0200	/* parity error flag */
    209 #define IEVME_INT   0x0100	/* interrupt flag */
    210 #define IEVME_P2EN  0x0020	/* enable p2 bus */
    211 #define IEVME_256K  0x0010	/* 256kb rams */
    212 #define IEVME_HADDR 0x000f	/* mask for bits 17-20 of address */
    213 
    214 /*
    215  * parity control
    216  */
    217 #define IEVME_PARACK 0x0100	/* parity error ack */
    218 #define IEVME_PARSRC 0x0080	/* parity error source */
    219 #define IEVME_PAREND 0x0040	/* which end of the data got the error */
    220 #define IEVME_PARADR 0x000f	/* mask to get bits 17-20 of parity address */
    221 
    222 /* Supported media */
    223 static int media[] = {
    224 	IFM_ETHER | IFM_10_2,
    225 };
    226 #define NMEDIA	(sizeof(media) / sizeof(media[0]))
    227 
    228 /*
    229  * the 3E board not supported (yet?)
    230  */
    231 
    232 
    233 static void ie_vmereset __P((struct ie_softc *, int));
    234 static void ie_vmeattend __P((struct ie_softc *, int));
    235 static void ie_vmerun __P((struct ie_softc *));
    236 static int  ie_vmeintr __P((struct ie_softc *, int));
    237 
    238 int ie_vme_match __P((struct device *, struct cfdata *, void *));
    239 void ie_vme_attach __P((struct device *, struct device *, void *));
    240 
    241 struct ie_vme_softc {
    242 	struct ie_softc ie;
    243 	bus_space_tag_t ievt;
    244 	bus_space_handle_t ievh;
    245 };
    246 
    247 CFATTACH_DECL(ie_vme, sizeof(struct ie_vme_softc),
    248     ie_vme_match, ie_vme_attach, NULL, NULL)
    249 
    250 #define read_iev(sc, reg) \
    251   bus_space_read_2(sc->ievt, sc->ievh, offsetof(struct ievme, reg))
    252 #define write_iev(sc, reg, val) \
    253   bus_space_write_2(sc->ievt, sc->ievh, offsetof(struct ievme, reg), val)
    254 
    255 /*
    256  * MULTIBUS/VME support routines
    257  */
    258 void
    259 ie_vmereset(sc, what)
    260 	struct ie_softc *sc;
    261 	int what;
    262 {
    263 	struct ie_vme_softc *vsc = (struct ie_vme_softc *)sc;
    264 	write_iev(vsc, status, IEVME_RESET);
    265 	delay(100);		/* XXX could be shorter? */
    266 	write_iev(vsc, status, 0);
    267 }
    268 
    269 void
    270 ie_vmeattend(sc, why)
    271 	struct ie_softc *sc;
    272 	int why;
    273 {
    274 	struct ie_vme_softc *vsc = (struct ie_vme_softc *)sc;
    275 
    276 	/* flag! */
    277 	write_iev(vsc, status, read_iev(vsc, status) | IEVME_ATTEN);
    278 	/* down. */
    279 	write_iev(vsc, status, read_iev(vsc, status) & ~IEVME_ATTEN);
    280 }
    281 
    282 void
    283 ie_vmerun(sc)
    284 	struct ie_softc *sc;
    285 {
    286 	struct ie_vme_softc *vsc = (struct ie_vme_softc *)sc;
    287 
    288 	write_iev(vsc, status, read_iev(vsc, status)
    289 		  | IEVME_ONAIR | IEVME_IENAB | IEVME_PEINT);
    290 }
    291 
    292 int
    293 ie_vmeintr(sc, where)
    294 	struct ie_softc *sc;
    295 	int where;
    296 {
    297 	struct ie_vme_softc *vsc = (struct ie_vme_softc *)sc;
    298 
    299 	if (where != INTR_ENTER)
    300 		return (0);
    301 
    302         /*
    303          * check for parity error
    304          */
    305 	if (read_iev(vsc, status) & IEVME_PERR) {
    306 		printf("%s: parity error (ctrl 0x%x @ 0x%02x%04x)\n",
    307 		       sc->sc_dev.dv_xname, read_iev(vsc, pectrl),
    308 		       read_iev(vsc, pectrl) & IEVME_HADDR,
    309 		       read_iev(vsc, peaddr));
    310 		write_iev(vsc, pectrl, read_iev(vsc, pectrl) | IEVME_PARACK);
    311 	}
    312 	return (0);
    313 }
    314 
    315 void ie_memcopyin __P((struct ie_softc *, void *, int, size_t));
    316 void ie_memcopyout __P((struct ie_softc *, const void *, int, size_t));
    317 
    318 /*
    319  * Copy board memory to kernel.
    320  */
    321 void
    322 ie_memcopyin(sc, p, offset, size)
    323 	struct ie_softc	*sc;
    324 	void *p;
    325 	int offset;
    326 	size_t size;
    327 {
    328 	size_t help;
    329 
    330 	if ((offset & 1) && ((u_long)p & 1) && size > 0) {
    331 		*(u_int8_t *)p = bus_space_read_1(sc->bt, sc->bh, offset);
    332 		offset++;
    333 		p = (u_int8_t *)p + 1;
    334 		size--;
    335 	}
    336 
    337 	if ((offset & 1) || ((u_long)p & 1)) {
    338 		bus_space_read_region_1(sc->bt, sc->bh, offset, p, size);
    339 		return;
    340 	}
    341 
    342 	help = size / 2;
    343 	bus_space_read_region_2(sc->bt, sc->bh, offset, p, help);
    344 	if (2 * help == size)
    345 		return;
    346 
    347 	offset += 2 * help;
    348 	p = (u_int16_t *)p + help;
    349 	*(u_int8_t *)p = bus_space_read_1(sc->bt, sc->bh, offset);
    350 }
    351 
    352 /*
    353  * Copy from kernel space to board memory.
    354  */
    355 void
    356 ie_memcopyout(sc, p, offset, size)
    357 	struct ie_softc	*sc;
    358 	const void *p;
    359 	int offset;
    360 	size_t size;
    361 {
    362 	size_t help;
    363 
    364 	if ((offset & 1) && ((u_long)p & 1) && size > 0) {
    365 		bus_space_write_1(sc->bt, sc->bh, offset, *(u_int8_t *)p);
    366 		offset++;
    367 		p = (u_int8_t *)p + 1;
    368 		size--;
    369 	}
    370 
    371 	if ((offset & 1) || ((u_long)p & 1)) {
    372 		bus_space_write_region_1(sc->bt, sc->bh, offset, p, size);
    373 		return;
    374 	}
    375 
    376 	help = size / 2;
    377 	bus_space_write_region_2(sc->bt, sc->bh, offset, p, help);
    378 	if (2 * help == size)
    379 		return;
    380 
    381 	offset += 2 * help;
    382 	p = (u_int16_t *)p + help;
    383 	bus_space_write_1(sc->bt, sc->bh, offset, *(u_int8_t *)p);
    384 }
    385 
    386 /* read a 16-bit value at BH offset */
    387 u_int16_t ie_vme_read16 __P((struct ie_softc *, int offset));
    388 /* write a 16-bit value at BH offset */
    389 void ie_vme_write16 __P((struct ie_softc *, int offset, u_int16_t value));
    390 void ie_vme_write24 __P((struct ie_softc *, int offset, int addr));
    391 
    392 u_int16_t
    393 ie_vme_read16(sc, offset)
    394 	struct ie_softc *sc;
    395 	int offset;
    396 {
    397 	u_int16_t v;
    398 
    399 	bus_space_barrier(sc->bt, sc->bh, offset, 2, BUS_SPACE_BARRIER_READ);
    400 	v = bus_space_read_2(sc->bt, sc->bh, offset);
    401 	return (((v&0xff)<<8) | ((v>>8)&0xff));
    402 }
    403 
    404 void
    405 ie_vme_write16(sc, offset, v)
    406 	struct ie_softc *sc;
    407 	int offset;
    408 	u_int16_t v;
    409 {
    410 	int v0 = ((((v)&0xff)<<8) | (((v)>>8)&0xff));
    411 	bus_space_write_2(sc->bt, sc->bh, offset, v0);
    412 	bus_space_barrier(sc->bt, sc->bh, offset, 2, BUS_SPACE_BARRIER_WRITE);
    413 }
    414 
    415 void
    416 ie_vme_write24(sc, offset, addr)
    417 	struct ie_softc *sc;
    418 	int offset;
    419 	int addr;
    420 {
    421 	u_char *f = (u_char *)&addr;
    422 	u_int16_t v0, v1;
    423 	u_char *t;
    424 
    425 	t = (u_char *)&v0;
    426 	t[0] = f[3]; t[1] = f[2];
    427 	bus_space_write_2(sc->bt, sc->bh, offset, v0);
    428 
    429 	t = (u_char *)&v1;
    430 	t[0] = f[1]; t[1] = 0;
    431 	bus_space_write_2(sc->bt, sc->bh, offset+2, v1);
    432 
    433 	bus_space_barrier(sc->bt, sc->bh, offset, 4, BUS_SPACE_BARRIER_WRITE);
    434 }
    435 
    436 int
    437 ie_vme_match(parent, cf, aux)
    438 	struct device *parent;
    439 	struct cfdata *cf;
    440 	void *aux;
    441 {
    442 	struct vme_attach_args *va = aux;
    443 	vme_chipset_tag_t ct = va->va_vct;
    444 	vme_am_t mod;
    445 	int error;
    446 
    447 	if (va->numcfranges < 2) {
    448 		printf("ie_vme_match: need 2 ranges\n");
    449 		return (0);
    450 	}
    451 	if ((va->r[1].offset & 0xff0fffff) ||
    452 	    ((va->r[0].offset & 0xfff00000)
    453 	     != (va->r[1].offset & 0xfff00000))) {
    454 		printf("ie_vme_match: base address mismatch\n");
    455 		return (0);
    456 	}
    457 	if (va->r[0].size != VMECF_LEN_DEFAULT &&
    458 	    va->r[0].size != sizeof(sizeof(struct ievme))) {
    459 		printf("ie_vme_match: bad csr size\n");
    460 		return (0);
    461 	}
    462 	if (va->r[1].size == VMECF_LEN_DEFAULT) {
    463 		printf("ie_vme_match: must specify memory size\n");
    464 		return (0);
    465 	}
    466 
    467 	mod = 0x3d; /* VME_AM_A24|VME_AM_MBO|VME_AM_SUPER|VME_AM_DATA */
    468 
    469 	if (va->r[0].am != VMECF_AM_DEFAULT &&
    470 	    va->r[0].am != mod)
    471 		return (0);
    472 
    473 	if (vme_space_alloc(va->va_vct, va->r[0].offset,
    474 			    sizeof(struct ievme), mod))
    475 		return (0);
    476 	if (vme_space_alloc(va->va_vct, va->r[1].offset,
    477 			    va->r[1].size, mod)) {
    478 		vme_space_free(va->va_vct, va->r[0].offset,
    479 			       sizeof(struct ievme), mod);
    480 		return (0);
    481 	}
    482 	error = vme_probe(ct, va->r[0].offset, 2, mod, VME_D16, 0, 0);
    483 	vme_space_free(va->va_vct, va->r[0].offset, sizeof(struct ievme), mod);
    484 	vme_space_free(va->va_vct, va->r[1].offset, va->r[1].size, mod);
    485 
    486 	return (error == 0);
    487 }
    488 
    489 void
    490 ie_vme_attach(parent, self, aux)
    491 	struct device *parent;
    492 	struct device *self;
    493 	void   *aux;
    494 {
    495 	u_int8_t myaddr[ETHER_ADDR_LEN];
    496 #ifdef __sparc__
    497 	extern void myetheraddr(u_char *);	/* should be elsewhere */
    498 #endif
    499 	struct ie_vme_softc *vsc = (void *) self;
    500 	struct vme_attach_args *va = aux;
    501 	vme_chipset_tag_t ct = va->va_vct;
    502 	struct ie_softc *sc;
    503 	vme_intr_handle_t ih;
    504 	vme_addr_t rampaddr;
    505 	vme_size_t memsize;
    506 	vme_mapresc_t resc;
    507 	int lcv;
    508 
    509 	vme_am_t mod;
    510 
    511 	/*
    512 	 * *note*: we don't detect the difference between a VME3E and
    513 	 * a multibus/vme card.   if you want to use a 3E you'll have
    514 	 * to fix this.
    515 	 */
    516 	mod = 0x3d; /* VME_AM_A24|VME_AM_MBO|VME_AM_SUPER|VME_AM_DATA */
    517 	if (vme_space_alloc(va->va_vct, va->r[0].offset,
    518 			    sizeof(struct ievme), mod) ||
    519 	    vme_space_alloc(va->va_vct, va->r[1].offset,
    520 			    va->r[1].size, mod))
    521 		panic("if_ie: vme alloc");
    522 
    523 	sc = &vsc->ie;
    524 
    525 	sc->hwreset = ie_vmereset;
    526 	sc->hwinit = ie_vmerun;
    527 	sc->chan_attn = ie_vmeattend;
    528 	sc->intrhook = ie_vmeintr;
    529 	sc->memcopyout = ie_memcopyout;
    530 	sc->memcopyin = ie_memcopyin;
    531 
    532 	sc->ie_bus_barrier = NULL;
    533 	sc->ie_bus_read16 = ie_vme_read16;
    534 	sc->ie_bus_write16 = ie_vme_write16;
    535 	sc->ie_bus_write24 = ie_vme_write24;
    536 
    537 	memsize = va->r[1].size;
    538 
    539 	if (vme_space_map(ct, va->r[0].offset, sizeof(struct ievme), mod,
    540 			  VME_D16 | VME_D8, 0,
    541 			  &vsc->ievt, &vsc->ievh, &resc) != 0)
    542 		panic("if_ie: vme map csr");
    543 
    544 	rampaddr = va->r[1].offset;
    545 
    546 	/* 4 more */
    547 	rampaddr = rampaddr | ((read_iev(vsc, status) & IEVME_HADDR) << 16);
    548 	if (vme_space_map(ct, rampaddr, memsize, mod, VME_D16 | VME_D8, 0,
    549 			  &sc->bt, &sc->bh, &resc) != 0)
    550 		panic("if_ie: vme map mem");
    551 
    552 	write_iev(vsc, pectrl, read_iev(vsc, pectrl) | IEVME_PARACK);
    553 
    554 	/*
    555 	 * Set up mappings, direct map except for last page
    556 	 * which is mapped at zero and at high address (for scp)
    557 	 */
    558 	for (lcv = 0; lcv < IEVME_MAPSZ - 1; lcv++)
    559 		write_iev(vsc, pgmap[lcv], IEVME_SBORDR | IEVME_OBMEM | lcv);
    560 	write_iev(vsc, pgmap[IEVME_MAPSZ - 1], IEVME_SBORDR | IEVME_OBMEM | 0);
    561 
    562 	/* Clear all ram */
    563 	bus_space_set_region_2(sc->bt, sc->bh, 0, 0, memsize/2);
    564 
    565 	/*
    566 	 * We use the first page to set up SCP, ICSP and SCB data
    567 	 * structures. The remaining pages become the buffer area
    568 	 * (managed in i82586.c).
    569 	 * SCP is in double-mapped page, so the 586 can see it at
    570 	 * the mandatory magic address (IE_SCP_ADDR).
    571 	 */
    572 	sc->scp = (IE_SCP_ADDR & (IEVME_PAGESIZE - 1));
    573 
    574 	/* iscp at location zero */
    575 	sc->iscp = 0;
    576 
    577 	/* scb follows iscp */
    578 	sc->scb = IE_ISCP_SZ;
    579 
    580 	ie_vme_write16(sc, IE_ISCP_SCB((long)sc->iscp), sc->scb);
    581 	ie_vme_write16(sc, IE_ISCP_BASE((u_long)sc->iscp), 0);
    582 	ie_vme_write24(sc, IE_SCP_ISCP((u_long)sc->scp), 0);
    583 
    584 	if (i82586_proberam(sc) == 0) {
    585 		printf(": memory probe failed\n");
    586 		return;
    587 	}
    588 
    589 	/*
    590 	 * Rest of first page is unused; rest of ram for buffers.
    591 	 */
    592 	sc->buf_area = IEVME_PAGESIZE;
    593 	sc->buf_area_sz = memsize - IEVME_PAGESIZE;
    594 
    595 	sc->do_xmitnopchain = 0;
    596 
    597 	printf("\n%s:", self->dv_xname);
    598 
    599 #ifdef __sparc__
    600 	myetheraddr(myaddr);
    601 #endif
    602 	i82586_attach(sc, "multibus/vme", myaddr, media, NMEDIA, media[0]);
    603 
    604 	vme_intr_map(ct, va->ilevel, va->ivector, &ih);
    605 	vme_intr_establish(ct, ih, IPL_NET, i82586_intr, sc);
    606 }
    607