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iommu.c revision 1.22
      1 /*	$NetBSD: iommu.c,v 1.22 2000/07/07 13:10:34 mrg Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1999, 2000 Matthew R. Green
      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. The name of the author may not be used to endorse or promote products
     16  *    derived from this software without specific prior written permission.
     17  *
     18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
     23  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     24  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
     25  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
     26  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     28  * SUCH DAMAGE.
     29  */
     30 
     31 /*-
     32  * Copyright (c) 1998 The NetBSD Foundation, Inc.
     33  * All rights reserved.
     34  *
     35  * This code is derived from software contributed to The NetBSD Foundation
     36  * by Paul Kranenburg.
     37  *
     38  * Redistribution and use in source and binary forms, with or without
     39  * modification, are permitted provided that the following conditions
     40  * are met:
     41  * 1. Redistributions of source code must retain the above copyright
     42  *    notice, this list of conditions and the following disclaimer.
     43  * 2. Redistributions in binary form must reproduce the above copyright
     44  *    notice, this list of conditions and the following disclaimer in the
     45  *    documentation and/or other materials provided with the distribution.
     46  * 3. All advertising materials mentioning features or use of this software
     47  *    must display the following acknowledgement:
     48  *        This product includes software developed by the NetBSD
     49  *        Foundation, Inc. and its contributors.
     50  * 4. Neither the name of The NetBSD Foundation nor the names of its
     51  *    contributors may be used to endorse or promote products derived
     52  *    from this software without specific prior written permission.
     53  *
     54  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     55  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     56  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     57  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     58  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     59  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     60  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     61  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     62  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     63  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     64  * POSSIBILITY OF SUCH DAMAGE.
     65  */
     66 
     67 /*
     68  * Copyright (c) 1992, 1993
     69  *	The Regents of the University of California.  All rights reserved.
     70  *
     71  * This software was developed by the Computer Systems Engineering group
     72  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
     73  * contributed to Berkeley.
     74  *
     75  * All advertising materials mentioning features or use of this software
     76  * must display the following acknowledgement:
     77  *	This product includes software developed by the University of
     78  *	California, Lawrence Berkeley Laboratory.
     79  *
     80  * Redistribution and use in source and binary forms, with or without
     81  * modification, are permitted provided that the following conditions
     82  * are met:
     83  * 1. Redistributions of source code must retain the above copyright
     84  *    notice, this list of conditions and the following disclaimer.
     85  * 2. Redistributions in binary form must reproduce the above copyright
     86  *    notice, this list of conditions and the following disclaimer in the
     87  *    documentation and/or other materials provided with the distribution.
     88  * 3. All advertising materials mentioning features or use of this software
     89  *    must display the following acknowledgement:
     90  *	This product includes software developed by the University of
     91  *	California, Berkeley and its contributors.
     92  * 4. Neither the name of the University nor the names of its contributors
     93  *    may be used to endorse or promote products derived from this software
     94  *    without specific prior written permission.
     95  *
     96  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     97  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     98  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     99  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
    100  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
    101  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
    102  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
    103  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    104  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
    105  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
    106  * SUCH DAMAGE.
    107  *
    108  *	from: NetBSD: sbus.c,v 1.13 1999/05/23 07:24:02 mrg Exp
    109  *	from: @(#)sbus.c	8.1 (Berkeley) 6/11/93
    110  */
    111 
    112 /*
    113  * UltraSPARC IOMMU support; used by both the sbus and pci code.
    114  */
    115 #include "opt_ddb.h"
    116 
    117 #include <sys/param.h>
    118 #include <sys/extent.h>
    119 #include <sys/malloc.h>
    120 #include <sys/systm.h>
    121 #include <sys/device.h>
    122 
    123 #include <uvm/uvm_extern.h>
    124 
    125 #include <machine/bus.h>
    126 #include <sparc64/sparc64/cache.h>
    127 #include <sparc64/dev/iommureg.h>
    128 #include <sparc64/dev/iommuvar.h>
    129 
    130 #include <machine/autoconf.h>
    131 #include <machine/cpu.h>
    132 
    133 #ifdef DEBUG
    134 #define IDB_BUSDMA	0x1
    135 #define IDB_IOMMU	0x2
    136 #define IDB_INFO	0x4
    137 int iommudebug = 0x0;
    138 #define DPRINTF(l, s)   do { if (iommudebug & l) printf s; } while (0)
    139 #else
    140 #define DPRINTF(l, s)
    141 #endif
    142 
    143 static	int iommu_strbuf_flush __P((struct iommu_state *));
    144 
    145 /*
    146  * initialise the UltraSPARC IOMMU (SBUS or PCI):
    147  *	- allocate and setup the iotsb.
    148  *	- enable the IOMMU
    149  *	- initialise the streaming buffers (if they exist)
    150  *	- create a private DVMA map.
    151  */
    152 void
    153 iommu_init(name, is, tsbsize)
    154 	char *name;
    155 	struct iommu_state *is;
    156 	int tsbsize;
    157 {
    158 	psize_t size;
    159 	vaddr_t va;
    160 	paddr_t pa;
    161 	vm_page_t m;
    162 	struct pglist mlist;
    163 
    164 	/*
    165 	 * Setup the iommu.
    166 	 *
    167 	 * The sun4u iommu is part of the SBUS or PCI controller so we
    168 	 * will deal with it here..
    169 	 *
    170 	 * The IOMMU address space always ends at 0xffffe000, but the starting
    171 	 * address depends on the size of the map.  The map size is 1024 * 2 ^
    172 	 * is->is_tsbsize entries, where each entry is 8 bytes.  The start of
    173 	 * the map can be calculated by (0xffffe000 << (8 + is->is_tsbsize)).
    174 	 *
    175 	 * Note: the stupid IOMMU ignores the high bits of an address, so a
    176 	 * NULL DMA pointer will be translated by the first page of the IOTSB.
    177 	 * To trap bugs we'll skip the first entry in the IOTSB.
    178 	 */
    179 	is->is_cr = (tsbsize << 16) | IOMMUCR_EN;
    180 	is->is_tsbsize = tsbsize;
    181 	is->is_dvmabase = IOTSB_VSTART(is->is_tsbsize) + NBPG;
    182 
    183 	/*
    184 	 * Allocate memory for I/O pagetables.  They need to be physically
    185 	 * contiguous.
    186 	 */
    187 
    188 	size = NBPG<<(is->is_tsbsize);
    189 	TAILQ_INIT(&mlist);
    190 	if (uvm_pglistalloc((psize_t)size, (paddr_t)0, (paddr_t)-1,
    191 		(paddr_t)NBPG, (paddr_t)0, &mlist, 1, 0) != 0)
    192 		panic("iommu_init: no memory");
    193 
    194 	va = uvm_km_valloc(kernel_map, size);
    195 	if (va == 0)
    196 		panic("iommu_init: no memory");
    197 	is->is_tsb = (int64_t *)va;
    198 
    199 	m = TAILQ_FIRST(&mlist);
    200 	is->is_ptsb = VM_PAGE_TO_PHYS(m);
    201 
    202 	/* Map the pages */
    203 	for (; m != NULL; m = TAILQ_NEXT(m,pageq)) {
    204 		pa = VM_PAGE_TO_PHYS(m);
    205 		pmap_enter(pmap_kernel(), va, pa | PMAP_NVC,
    206 			VM_PROT_READ|VM_PROT_WRITE,
    207 			VM_PROT_READ|VM_PROT_WRITE|PMAP_WIRED);
    208 		va += NBPG;
    209 	}
    210 	bzero(is->is_tsb, size);
    211 
    212 #ifdef DEBUG
    213 	if (iommudebug & IDB_INFO)
    214 	{
    215 		/* Probe the iommu */
    216 		struct iommureg *regs = is->is_iommu;
    217 
    218 		printf("iommu regs at: cr=%lx tsb=%lx flush=%lx\n", &regs->iommu_cr,
    219 		       &regs->iommu_tsb, &regs->iommu_flush);
    220 		printf("iommu cr=%qx tsb=%qx\n", regs->iommu_cr, regs->iommu_tsb);
    221 		printf("TSB base %p phys %qx\n", (void *)is->is_tsb, (u_int64_t)is->is_ptsb);
    222 		delay(1000000); /* 1 s */
    223 	}
    224 #endif
    225 
    226 	/*
    227 	 * Initialize streaming buffer, if it is there.
    228 	 */
    229 	if (is->is_sb)
    230 		(void)pmap_extract(pmap_kernel(), (vaddr_t)&is->is_flush,
    231 		    (paddr_t *)&is->is_flushpa);
    232 
    233 	/*
    234 	 * now actually start up the IOMMU
    235 	 */
    236 	iommu_reset(is);
    237 
    238 	/*
    239 	 * Now all the hardware's working we need to allocate a dvma map.
    240 	 */
    241 	printf("DVMA map: %x to %x\n",
    242 		(unsigned int)is->is_dvmabase,
    243 		(unsigned int)IOTSB_VEND);
    244 	is->is_dvmamap = extent_create(name,
    245 				       is->is_dvmabase, (u_long)IOTSB_VEND,
    246 				       M_DEVBUF, 0, 0, EX_NOWAIT);
    247 }
    248 
    249 /*
    250  * Streaming buffers don't exist on the UltraSPARC IIi; we should have
    251  * detected that already and disabled them.  If not, we will notice that
    252  * they aren't there when the STRBUF_EN bit does not remain.
    253  */
    254 void
    255 iommu_reset(is)
    256 	struct iommu_state *is;
    257 {
    258 
    259 	/* Need to do 64-bit stores */
    260 	bus_space_write_8(is->is_bustag,
    261 			  (bus_space_handle_t)(u_long)&is->is_iommu->iommu_tsb,
    262 			  0, is->is_ptsb);
    263 	/* Enable IOMMU in diagnostic mode */
    264 	bus_space_write_8(is->is_bustag,
    265 			  (bus_space_handle_t)(u_long)&is->is_iommu->iommu_cr, 0,
    266 			  is->is_cr|IOMMUCR_DE);
    267 
    268 
    269 	if (!is->is_sb)
    270 		return;
    271 
    272 	/* Enable diagnostics mode? */
    273 	bus_space_write_8(is->is_bustag,
    274 			  (bus_space_handle_t)(u_long)&is->is_sb->strbuf_ctl,
    275 			  0, STRBUF_EN);
    276 
    277 	/* No streaming buffers? Disable them */
    278 	if (bus_space_read_8(is->is_bustag,
    279 			     (bus_space_handle_t)(u_long)&is->is_sb->strbuf_ctl,
    280 			     0) == 0)
    281 		is->is_sb = 0;
    282 }
    283 
    284 /*
    285  * Here are the iommu control routines.
    286  */
    287 void
    288 iommu_enter(is, va, pa, flags)
    289 	struct iommu_state *is;
    290 	vaddr_t va;
    291 	int64_t pa;
    292 	int flags;
    293 {
    294 	int64_t tte;
    295 
    296 #ifdef DIAGNOSTIC
    297 	if (va < is->is_dvmabase)
    298 		panic("iommu_enter: va %#lx not in DVMA space", va);
    299 #endif
    300 
    301 	tte = MAKEIOTTE(pa, !(flags&BUS_DMA_NOWRITE), !(flags&BUS_DMA_NOCACHE),
    302 			!(flags&BUS_DMA_COHERENT));
    303 
    304 	/* Is the streamcache flush really needed? */
    305 	if (is->is_sb) {
    306 		bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
    307 				  &is->is_sb->strbuf_pgflush, 0, va);
    308 		iommu_strbuf_flush(is);
    309 	}
    310 	DPRINTF(IDB_IOMMU, ("Clearing TSB slot %d for va %p\n",
    311 		       (int)IOTSBSLOT(va,is->is_tsbsize), va));
    312 	is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)] = tte;
    313 	bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
    314 			  &is->is_iommu->iommu_flush, 0, va);
    315 	DPRINTF(IDB_IOMMU, ("iommu_enter: va %lx pa %lx TSB[%lx]@%p=%lx\n",
    316 		       va, (long)pa, IOTSBSLOT(va,is->is_tsbsize),
    317 		       &is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)],
    318 		       (long)tte));
    319 }
    320 
    321 /*
    322  * iommu_remove: removes mappings created by iommu_enter
    323  *
    324  * Only demap from IOMMU if flag is set.
    325  *
    326  * XXX: this function needs better internal error checking.
    327  */
    328 void
    329 iommu_remove(is, va, len)
    330 	struct iommu_state *is;
    331 	vaddr_t va;
    332 	size_t len;
    333 {
    334 
    335 #ifdef DIAGNOSTIC
    336 	if (va < is->is_dvmabase)
    337 		panic("iommu_remove: va 0x%lx not in DVMA space", (long)va);
    338 	if ((long)(va + len) < (long)va)
    339 		panic("iommu_remove: va 0x%lx + len 0x%lx wraps",
    340 		      (long) va, (long) len);
    341 	if (len & ~0xfffffff)
    342 		panic("iommu_remove: rediculous len 0x%lx", (long)len);
    343 #endif
    344 
    345 	va = trunc_page(va);
    346 	DPRINTF(IDB_IOMMU, ("iommu_remove: va %lx TSB[%lx]@%p\n",
    347 	    va, IOTSBSLOT(va,is->is_tsbsize),
    348 	    &is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)]));
    349 	while (len > 0) {
    350 		DPRINTF(IDB_IOMMU, ("iommu_remove: clearing TSB slot %d for va %p size %lx\n",
    351 		    (int)IOTSBSLOT(va,is->is_tsbsize), va, (u_long)len));
    352 		if (is->is_sb) {
    353 			DPRINTF(IDB_IOMMU, ("iommu_remove: flushing va %p TSB[%lx]@%p=%lx, %lu bytes left\n",
    354 			       (long)va, (long)IOTSBSLOT(va,is->is_tsbsize),
    355 			       (long)&is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)],
    356 			       (long)(is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)]),
    357 			       (u_long)len));
    358 			bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
    359 					  &is->is_sb->strbuf_pgflush, 0, va);
    360 			if (len <= NBPG)
    361 				iommu_strbuf_flush(is);
    362 			DPRINTF(IDB_IOMMU, ("iommu_remove: flushed va %p TSB[%lx]@%p=%lx, %lu bytes left\n",
    363 			       (long)va, (long)IOTSBSLOT(va,is->is_tsbsize),
    364 			       (long)&is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)],
    365 			       (long)(is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)]),
    366 			       (u_long)len));
    367 		} else
    368 			membar_sync();	/* XXX */
    369 
    370 		if (len <= NBPG)
    371 			len = 0;
    372 		else
    373 			len -= NBPG;
    374 
    375 		is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)] = 0;
    376 		bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
    377 				  &is->is_iommu->iommu_flush, 0, va);
    378 		va += NBPG;
    379 	}
    380 }
    381 
    382 static int
    383 iommu_strbuf_flush(is)
    384 	struct iommu_state *is;
    385 {
    386 	struct timeval cur, flushtimeout;
    387 
    388 #define BUMPTIME(t, usec) { \
    389 	register volatile struct timeval *tp = (t); \
    390 	register long us; \
    391  \
    392 	tp->tv_usec = us = tp->tv_usec + (usec); \
    393 	if (us >= 1000000) { \
    394 		tp->tv_usec = us - 1000000; \
    395 		tp->tv_sec++; \
    396 	} \
    397 }
    398 
    399 	if (!is->is_sb)
    400 		return (0);
    401 
    402 	/*
    403 	 * Streaming buffer flushes:
    404 	 *
    405 	 *   1 Tell strbuf to flush by storing va to strbuf_pgflush.  If
    406 	 *     we're not on a cache line boundary (64-bits):
    407 	 *   2 Store 0 in flag
    408 	 *   3 Store pointer to flag in flushsync
    409 	 *   4 wait till flushsync becomes 0x1
    410 	 *
    411 	 * If it takes more than .5 sec, something
    412 	 * went wrong.
    413 	 */
    414 
    415 	is->is_flush = 0;
    416 	membar_sync();
    417 	bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
    418 			  &is->is_sb->strbuf_flushsync, 0, is->is_flushpa);
    419 	membar_sync();
    420 
    421 	microtime(&flushtimeout);
    422 	cur = flushtimeout;
    423 	BUMPTIME(&flushtimeout, 500000); /* 1/2 sec */
    424 
    425 	DPRINTF(IDB_IOMMU, ("iommu_strbuf_flush: flush = %lx at va = %lx pa = %lx now=%lx:%lx until = %lx:%lx\n",
    426 		       (long)is->is_flush, (long)&is->is_flush,
    427 		       (long)is->is_flushpa, cur.tv_sec, cur.tv_usec,
    428 		       flushtimeout.tv_sec, flushtimeout.tv_usec));
    429 	/* Bypass non-coherent D$ */
    430 	while (!ldxa(is->is_flushpa, ASI_PHYS_CACHED) &&
    431 	       ((cur.tv_sec <= flushtimeout.tv_sec) &&
    432 		(cur.tv_usec <= flushtimeout.tv_usec)))
    433 		microtime(&cur);
    434 
    435 #ifdef DIAGNOSTIC
    436 	if (!is->is_flush) {
    437 		printf("iommu_strbuf_flush: flush timeout %p at %p\n", (long)is->is_flush,
    438 		       (long)is->is_flushpa); /* panic? */
    439 #ifdef DDB
    440 		Debugger();
    441 #endif
    442 	}
    443 #endif
    444 	DPRINTF(IDB_IOMMU, ("iommu_strbuf_flush: flushed\n"));
    445 	return (is->is_flush);
    446 }
    447 
    448 /*
    449  * IOMMU DVMA operations, common to SBUS and PCI.
    450  */
    451 int
    452 iommu_dvmamap_load(t, is, map, buf, buflen, p, flags)
    453 	bus_dma_tag_t t;
    454 	struct iommu_state *is;
    455 	bus_dmamap_t map;
    456 	void *buf;
    457 	bus_size_t buflen;
    458 	struct proc *p;
    459 	int flags;
    460 {
    461 	int s;
    462 	int err;
    463 	bus_size_t sgsize;
    464 	paddr_t curaddr;
    465 	u_long dvmaddr;
    466 	bus_size_t align, boundary;
    467 	vaddr_t vaddr = (vaddr_t)buf;
    468 	pmap_t pmap;
    469 
    470 	if (map->dm_nsegs) {
    471 		/* Already in use?? */
    472 #ifdef DIAGNOSTIC
    473 		printf("iommu_dvmamap_load: map still in use\n");
    474 #endif
    475 		bus_dmamap_unload(t, map);
    476 	}
    477 	/*
    478 	 * Make sure that on error condition we return "no valid mappings".
    479 	 */
    480 	map->dm_nsegs = 0;
    481 
    482 	if (buflen > map->_dm_size) {
    483 		DPRINTF(IDB_BUSDMA,
    484 		    ("iommu_dvmamap_load(): error %d > %d -- "
    485 		     "map size exceeded!\n", buflen, map->_dm_size));
    486 		return (EINVAL);
    487 	}
    488 
    489 	sgsize = round_page(buflen + ((int)vaddr & PGOFSET));
    490 
    491 	/*
    492 	 * A boundary presented to bus_dmamem_alloc() takes precedence
    493 	 * over boundary in the map.
    494 	 */
    495 	if ((boundary = (map->dm_segs[0]._ds_boundary)) == 0)
    496 		boundary = map->_dm_boundary;
    497 	align = max(map->dm_segs[0]._ds_align, NBPG);
    498 	s = splhigh();
    499 	err = extent_alloc(is->is_dvmamap, sgsize, align,
    500 	    boundary, EX_NOWAIT|EX_BOUNDZERO, (u_long *)&dvmaddr);
    501 	splx(s);
    502 
    503 #ifdef DEBUG
    504 	if (err || (dvmaddr == (bus_addr_t)-1))
    505 	{
    506 		printf("iommu_dvmamap_load(): extent_alloc(%d, %x) failed!\n",
    507 		    sgsize, flags);
    508 		Debugger();
    509 	}
    510 #endif
    511 	if (err != 0)
    512 		return (err);
    513 
    514 	if (dvmaddr == (bus_addr_t)-1)
    515 		return (ENOMEM);
    516 
    517 	/*
    518 	 * We always use just one segment.
    519 	 */
    520 	map->dm_mapsize = buflen;
    521 	map->dm_nsegs = 1;
    522 	map->dm_segs[0].ds_addr = dvmaddr + (vaddr & PGOFSET);
    523 	map->dm_segs[0].ds_len = buflen;
    524 
    525 	if (p != NULL)
    526 		pmap = p->p_vmspace->vm_map.pmap;
    527 	else
    528 		pmap = pmap_kernel();
    529 
    530 	dvmaddr = trunc_page(map->dm_segs[0].ds_addr);
    531 	for (; buflen > 0; ) {
    532 		/*
    533 		 * Get the physical address for this page.
    534 		 */
    535 		if (pmap_extract(pmap, (vaddr_t)vaddr, &curaddr) == FALSE) {
    536 			bus_dmamap_unload(t, map);
    537 			return (-1);
    538 		}
    539 
    540 		/*
    541 		 * Compute the segment size, and adjust counts.
    542 		 */
    543 		sgsize = NBPG - ((u_long)vaddr & PGOFSET);
    544 		if (buflen < sgsize)
    545 			sgsize = buflen;
    546 
    547 		DPRINTF(IDB_BUSDMA,
    548 		    ("iommu_dvmamap_load: map %p loading va %p dva %lx at pa %lx\n",
    549 		    map, (void *)vaddr, (long)dvmaddr, (long)(curaddr&~(NBPG-1))));
    550 		iommu_enter(is, trunc_page(dvmaddr), trunc_page(curaddr),
    551 		    flags);
    552 
    553 		dvmaddr += PAGE_SIZE;
    554 		vaddr += sgsize;
    555 		buflen -= sgsize;
    556 	}
    557 	return (0);
    558 }
    559 
    560 
    561 void
    562 iommu_dvmamap_unload(t, is, map)
    563 	bus_dma_tag_t t;
    564 	struct iommu_state *is;
    565 	bus_dmamap_t map;
    566 {
    567 	vaddr_t addr;
    568 	size_t len;
    569 	int error, s;
    570 	bus_addr_t dvmaddr;
    571 	bus_size_t sgsize;
    572 
    573 	if (map->dm_nsegs != 1)
    574 		panic("iommu_dvmamap_unload: nsegs = %d", map->dm_nsegs);
    575 
    576 	addr = trunc_page(map->dm_segs[0].ds_addr);
    577 	len = map->dm_segs[0].ds_len;
    578 
    579 	DPRINTF(IDB_BUSDMA,
    580 	    ("iommu_dvmamap_unload: map %p removing va %lx size %lx\n",
    581 	    map, (long)addr, (long)len));
    582 	iommu_remove(is, addr, len);
    583 	dvmaddr = (map->dm_segs[0].ds_addr & ~PGOFSET);
    584 	sgsize = round_page(map->dm_segs[0].ds_len +
    585 			    ((int)map->dm_segs[0].ds_addr & PGOFSET));
    586 
    587 	/* Mark the mappings as invalid. */
    588 	map->dm_mapsize = 0;
    589 	map->dm_nsegs = 0;
    590 
    591 	s = splhigh();
    592 	error = extent_free(is->is_dvmamap, dvmaddr, sgsize, EX_NOWAIT);
    593 	splx(s);
    594 	if (error != 0)
    595 		printf("warning: %qd of DVMA space lost\n", (long long)sgsize);
    596 	cache_flush((caddr_t)(u_long)dvmaddr, (u_int)sgsize);
    597 }
    598 
    599 
    600 int
    601 iommu_dvmamap_load_raw(t, is, map, segs, nsegs, flags, size)
    602 	bus_dma_tag_t t;
    603 	struct iommu_state *is;
    604 	bus_dmamap_t map;
    605 	bus_dma_segment_t *segs;
    606 	int nsegs;
    607 	int flags;
    608 	bus_size_t size;
    609 {
    610 	vm_page_t m;
    611 	int s;
    612 	int err;
    613 	bus_size_t sgsize;
    614 	paddr_t pa;
    615 	bus_size_t boundary, align;
    616 	u_long dvmaddr;
    617 	struct pglist *mlist;
    618 	int pagesz = PAGE_SIZE;
    619 
    620 	if (map->dm_nsegs) {
    621 		/* Already in use?? */
    622 #ifdef DIAGNOSTIC
    623 		printf("iommu_dvmamap_load_raw: map still in use\n");
    624 #endif
    625 		bus_dmamap_unload(t, map);
    626 	}
    627 	/*
    628 	 * Make sure that on error condition we return "no valid mappings".
    629 	 */
    630 	map->dm_nsegs = 0;
    631 #ifdef DIAGNOSTIC
    632 	/* XXX - unhelpful since we can't reset these in map_unload() */
    633 	if (segs[0].ds_addr != 0)
    634 		panic("iommu_dvmamap_load_raw: segment already loaded: "
    635 			"addr %#llx, size %#llx",
    636 			(u_int64_t)segs[0].ds_addr, (u_int64_t)segs[0].ds_len);
    637 	if (segs[0].ds_len != size)
    638 		panic("iommu_dvmamap_load_raw: segment size changed: "
    639 			"ds_len %#llx size %#llx", segs[0].ds_len, size);
    640 #endif
    641 	sgsize = round_page(size);
    642 
    643 	/*
    644 	 * A boundary presented to bus_dmamem_alloc() takes precedence
    645 	 * over boundary in the map.
    646 	 */
    647 	if ((boundary = segs[0]._ds_boundary) == 0)
    648 		boundary = map->_dm_boundary;
    649 
    650 	align = max(segs[0]._ds_align, NBPG);
    651 	s = splhigh();
    652 	err = extent_alloc(is->is_dvmamap, sgsize, align, boundary,
    653 	   ((flags & BUS_DMA_NOWAIT) == 0 ? EX_WAITOK : EX_NOWAIT)|EX_BOUNDZERO,
    654 	    (u_long *)&dvmaddr);
    655 	splx(s);
    656 
    657 	if (err != 0)
    658 		return (err);
    659 
    660 #ifdef DEBUG
    661 	if (dvmaddr == (bus_addr_t)-1)
    662 	{
    663 		printf("iommu_dvmamap_load_raw(): extent_alloc(%d, %x) failed!\n",
    664 		    sgsize, flags);
    665 		Debugger();
    666 	}
    667 #endif
    668 	if (dvmaddr == (bus_addr_t)-1)
    669 		return (ENOMEM);
    670 
    671 	/*
    672 	 * We always use just one segment.
    673 	 */
    674 	map->dm_mapsize = size;
    675 	map->dm_nsegs = 1;
    676 	map->dm_segs[0].ds_addr = dvmaddr;
    677 	map->dm_segs[0].ds_len = size;
    678 
    679 	mlist = segs[0]._ds_mlist;
    680 	for (m = TAILQ_FIRST(mlist); m != NULL; m = TAILQ_NEXT(m,pageq)) {
    681 		if (sgsize == 0)
    682 			panic("iommu_dmamap_load_raw: size botch");
    683 		pa = VM_PAGE_TO_PHYS(m);
    684 
    685 		DPRINTF(IDB_BUSDMA,
    686 		    ("iommu_dvmamap_load_raw: map %p loading va %lx at pa %lx\n",
    687 		    map, (long)dvmaddr, (long)(pa)));
    688 		iommu_enter(is, dvmaddr, pa, flags);
    689 
    690 		dvmaddr += pagesz;
    691 		sgsize -= pagesz;
    692 	}
    693 	return (0);
    694 }
    695 
    696 void
    697 iommu_dvmamap_sync(t, is, map, offset, len, ops)
    698 	bus_dma_tag_t t;
    699 	struct iommu_state *is;
    700 	bus_dmamap_t map;
    701 	bus_addr_t offset;
    702 	bus_size_t len;
    703 	int ops;
    704 {
    705 	vaddr_t va = map->dm_segs[0].ds_addr + offset;
    706 
    707 	/*
    708 	 * We only support one DMA segment; supporting more makes this code
    709          * too unweildy.
    710 	 */
    711 
    712 	if (ops & BUS_DMASYNC_PREREAD) {
    713 		DPRINTF(IDB_BUSDMA,
    714 		    ("iommu_dvmamap_sync: syncing va %p len %lu "
    715 		     "BUS_DMASYNC_PREREAD\n", (long)va, (u_long)len));
    716 
    717 		/* Nothing to do */;
    718 	}
    719 	if (ops & BUS_DMASYNC_POSTREAD) {
    720 		DPRINTF(IDB_BUSDMA,
    721 		    ("iommu_dvmamap_sync: syncing va %p len %lu "
    722 		     "BUS_DMASYNC_POSTREAD\n", (long)va, (u_long)len));
    723 		/* if we have a streaming buffer, flush it here first */
    724 		if (is->is_sb)
    725 			while (len > 0) {
    726 				DPRINTF(IDB_BUSDMA,
    727 				    ("iommu_dvmamap_sync: flushing va %p, %lu "
    728 				     "bytes left\n", (long)va, (u_long)len));
    729 				bus_space_write_8(is->is_bustag,
    730 						  (bus_space_handle_t)(u_long)
    731 						  &is->is_sb->strbuf_pgflush, 0, va);
    732 				if (len <= NBPG) {
    733 					iommu_strbuf_flush(is);
    734 					len = 0;
    735 				} else
    736 					len -= NBPG;
    737 				va += NBPG;
    738 			}
    739 	}
    740 	if (ops & BUS_DMASYNC_PREWRITE) {
    741 		DPRINTF(IDB_BUSDMA,
    742 		    ("iommu_dvmamap_sync: syncing va %p len %lu "
    743 		     "BUS_DMASYNC_PREWRITE\n", (long)va, (u_long)len));
    744 		/* Nothing to do */;
    745 	}
    746 	if (ops & BUS_DMASYNC_POSTWRITE) {
    747 		DPRINTF(IDB_BUSDMA,
    748 		    ("iommu_dvmamap_sync: syncing va %p len %lu "
    749 		     "BUS_DMASYNC_POSTWRITE\n", (long)va, (u_long)len));
    750 		/* Nothing to do */;
    751 	}
    752 }
    753 
    754 int
    755 iommu_dvmamem_alloc(t, is, size, alignment, boundary, segs, nsegs, rsegs, flags)
    756 	bus_dma_tag_t t;
    757 	struct iommu_state *is;
    758 	bus_size_t size, alignment, boundary;
    759 	bus_dma_segment_t *segs;
    760 	int nsegs;
    761 	int *rsegs;
    762 	int flags;
    763 {
    764 
    765 	DPRINTF(IDB_BUSDMA, ("iommu_dvmamem_alloc: sz %qx align %qx bound %qx "
    766 	   "segp %p flags %d\n", size, alignment, boundary, segs, flags));
    767 	return (bus_dmamem_alloc(t->_parent, size, alignment, boundary,
    768 	    segs, nsegs, rsegs, flags|BUS_DMA_DVMA));
    769 }
    770 
    771 void
    772 iommu_dvmamem_free(t, is, segs, nsegs)
    773 	bus_dma_tag_t t;
    774 	struct iommu_state *is;
    775 	bus_dma_segment_t *segs;
    776 	int nsegs;
    777 {
    778 
    779 	DPRINTF(IDB_BUSDMA, ("iommu_dvmamem_free: segp %p nsegs %d\n",
    780 	    segs, nsegs));
    781 	bus_dmamem_free(t->_parent, segs, nsegs);
    782 }
    783 
    784 /*
    785  * Map the DVMA mappings into the kernel pmap.
    786  * Check the flags to see whether we're streaming or coherent.
    787  */
    788 int
    789 iommu_dvmamem_map(t, is, segs, nsegs, size, kvap, flags)
    790 	bus_dma_tag_t t;
    791 	struct iommu_state *is;
    792 	bus_dma_segment_t *segs;
    793 	int nsegs;
    794 	size_t size;
    795 	caddr_t *kvap;
    796 	int flags;
    797 {
    798 	vm_page_t m;
    799 	vaddr_t va;
    800 	bus_addr_t addr;
    801 	struct pglist *mlist;
    802 	int cbit;
    803 
    804 	DPRINTF(IDB_BUSDMA, ("iommu_dvmamem_map: segp %p nsegs %d size %lx\n",
    805 	    segs, nsegs, size));
    806 
    807 	/*
    808 	 * Allocate some space in the kernel map, and then map these pages
    809 	 * into this space.
    810 	 */
    811 	size = round_page(size);
    812 	va = uvm_km_valloc(kernel_map, size);
    813 	if (va == 0)
    814 		return (ENOMEM);
    815 
    816 	*kvap = (caddr_t)va;
    817 
    818 	/*
    819 	 * digest flags:
    820 	 */
    821 	cbit = 0;
    822 	if (flags & BUS_DMA_COHERENT)	/* Disable vcache */
    823 		cbit |= PMAP_NVC;
    824 	if (flags & BUS_DMA_NOCACHE)	/* sideffects */
    825 		cbit |= PMAP_NC;
    826 
    827 	/*
    828 	 * Now take this and map it into the CPU.
    829 	 */
    830 	mlist = segs[0]._ds_mlist;
    831 	for (m = mlist->tqh_first; m != NULL; m = m->pageq.tqe_next) {
    832 #ifdef DIAGNOSTIC
    833 		if (size == 0)
    834 			panic("iommu_dvmamem_map: size botch");
    835 #endif
    836 		addr = VM_PAGE_TO_PHYS(m);
    837 		DPRINTF(IDB_BUSDMA, ("iommu_dvmamem_map: "
    838 		    "mapping va %lx at %qx\n", va, addr | cbit));
    839 		pmap_enter(pmap_kernel(), va, addr | cbit,
    840 		    VM_PROT_READ | VM_PROT_WRITE, PMAP_WIRED);
    841 		va += PAGE_SIZE;
    842 		size -= PAGE_SIZE;
    843 	}
    844 
    845 	return (0);
    846 }
    847 
    848 /*
    849  * Unmap DVMA mappings from kernel
    850  */
    851 void
    852 iommu_dvmamem_unmap(t, is, kva, size)
    853 	bus_dma_tag_t t;
    854 	struct iommu_state *is;
    855 	caddr_t kva;
    856 	size_t size;
    857 {
    858 
    859 	DPRINTF(IDB_BUSDMA, ("iommu_dvmamem_unmap: kvm %p size %lx\n",
    860 	    kva, size));
    861 
    862 #ifdef DIAGNOSTIC
    863 	if ((u_long)kva & PGOFSET)
    864 		panic("iommu_dvmamem_unmap");
    865 #endif
    866 
    867 	size = round_page(size);
    868 	pmap_remove(pmap_kernel(), (vaddr_t)kva, size);
    869 #if 0
    870 	/*
    871 	 * XXX ? is this necessary? i think so and i think other
    872 	 * implementations are missing it.
    873 	 */
    874 	uvm_km_free(kernel_map, (vaddr_t)kva, size);
    875 #endif
    876 }
    877