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int_bus_dma.c revision 1.1.2.3
      1 /*	$NetBSD: int_bus_dma.c,v 1.1.2.3 2002/02/28 04:09:12 nathanw Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9  * NASA Ames Research Center.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by the NetBSD
     22  *	Foundation, Inc. and its contributors.
     23  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24  *    contributors may be used to endorse or promote products derived
     25  *    from this software without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37  * POSSIBILITY OF SUCH DAMAGE.
     38  */
     39 /*
     40  * The integrator board has memory steering hardware that means that
     41  * the normal physical addresses used by the processor cannot be used
     42  * for DMA.  Instead we have to use the "core module alias mapping
     43  * addresses".  We don't use these for normal processor accesses since
     44  * they are much slower than the direct addresses when accessing
     45  * memory on the local board.
     46  */
     47 
     48 #include <sys/param.h>
     49 #include <sys/systm.h>
     50 #include <sys/kernel.h>
     51 #include <sys/map.h>
     52 #include <sys/proc.h>
     53 #include <sys/buf.h>
     54 #include <sys/reboot.h>
     55 #include <sys/conf.h>
     56 #include <sys/file.h>
     57 #include <sys/malloc.h>
     58 #include <sys/mbuf.h>
     59 #include <sys/vnode.h>
     60 #include <sys/device.h>
     61 
     62 #include <uvm/uvm_extern.h>
     63 
     64 #define _ARM32_BUS_DMA_PRIVATE
     65 #include <evbarm/integrator/int_bus_dma.h>
     66 
     67 #include <machine/cpu.h>
     68 #include <arm/cpufunc.h>
     69 
     70 static int	integrator_bus_dmamap_load_buffer __P((bus_dma_tag_t,
     71 		    bus_dmamap_t, void *, bus_size_t, struct proc *, int,
     72 		    vm_offset_t *, int *, int));
     73 static int	integrator_bus_dma_inrange __P((bus_dma_segment_t *, int,
     74 		    bus_addr_t));
     75 
     76 /*
     77  * Common function for loading a DMA map with a linear buffer.  May
     78  * be called by bus-specific DMA map load functions.
     79  */
     80 int
     81 integrator_bus_dmamap_load(t, map, buf, buflen, p, flags)
     82 	bus_dma_tag_t t;
     83 	bus_dmamap_t map;
     84 	void *buf;
     85 	bus_size_t buflen;
     86 	struct proc *p;
     87 	int flags;
     88 {
     89 	vm_offset_t lastaddr;
     90 	int seg, error;
     91 
     92 #ifdef DEBUG_DMA
     93 	printf("dmamap_load: t=%p map=%p buf=%p len=%lx p=%p f=%d\n",
     94 	    t, map, buf, buflen, p, flags);
     95 #endif	/* DEBUG_DMA */
     96 
     97 	/*
     98 	 * Make sure that on error condition we return "no valid mappings".
     99 	 */
    100 	map->dm_mapsize = 0;
    101 	map->dm_nsegs = 0;
    102 
    103 	if (buflen > map->_dm_size)
    104 		return (EINVAL);
    105 
    106 	seg = 0;
    107 	error = integrator_bus_dmamap_load_buffer(t, map, buf, buflen, p, flags,
    108 	    &lastaddr, &seg, 1);
    109 	if (error == 0) {
    110 		map->dm_mapsize = buflen;
    111 		map->dm_nsegs = seg + 1;
    112 		map->_dm_proc = p;
    113 	}
    114 #ifdef DEBUG_DMA
    115 	printf("dmamap_load: error=%d\n", error);
    116 #endif	/* DEBUG_DMA */
    117 	return (error);
    118 }
    119 
    120 /*
    121  * Like _bus_dmamap_load(), but for mbufs.
    122  */
    123 int
    124 integrator_bus_dmamap_load_mbuf(t, map, m0, flags)
    125 	bus_dma_tag_t t;
    126 	bus_dmamap_t map;
    127 	struct mbuf *m0;
    128 	int flags;
    129 {
    130 	vm_offset_t lastaddr;
    131 	int seg, error, first;
    132 	struct mbuf *m;
    133 
    134 #ifdef DEBUG_DMA
    135 	printf("dmamap_load_mbuf: t=%p map=%p m0=%p f=%d\n",
    136 	    t, map, m0, flags);
    137 #endif	/* DEBUG_DMA */
    138 
    139 	/*
    140 	 * Make sure that on error condition we return "no valid mappings."
    141 	 */
    142 	map->dm_mapsize = 0;
    143 	map->dm_nsegs = 0;
    144 
    145 #ifdef DIAGNOSTIC
    146 	if ((m0->m_flags & M_PKTHDR) == 0)
    147 		panic("integrator_bus_dmamap_load_mbuf: no packet header");
    148 #endif	/* DIAGNOSTIC */
    149 
    150 	if (m0->m_pkthdr.len > map->_dm_size)
    151 		return (EINVAL);
    152 
    153 	first = 1;
    154 	seg = 0;
    155 	error = 0;
    156 	for (m = m0; m != NULL && error == 0; m = m->m_next) {
    157 		error = integrator_bus_dmamap_load_buffer(t, map, m->m_data,
    158 		    m->m_len, NULL, flags, &lastaddr, &seg, first);
    159 		first = 0;
    160 	}
    161 	if (error == 0) {
    162 		map->dm_mapsize = m0->m_pkthdr.len;
    163 		map->dm_nsegs = seg + 1;
    164 		map->_dm_proc = NULL;	/* always kernel */
    165 	}
    166 #ifdef DEBUG_DMA
    167 	printf("dmamap_load_mbuf: error=%d\n", error);
    168 #endif	/* DEBUG_DMA */
    169 	return (error);
    170 }
    171 
    172 /*
    173  * Like _bus_dmamap_load(), but for uios.
    174  */
    175 int
    176 integrator_bus_dmamap_load_uio(t, map, uio, flags)
    177 	bus_dma_tag_t t;
    178 	bus_dmamap_t map;
    179 	struct uio *uio;
    180 	int flags;
    181 {
    182 	vm_offset_t lastaddr;
    183 	int seg, i, error, first;
    184 	bus_size_t minlen, resid;
    185 	struct proc *p = NULL;
    186 	struct iovec *iov;
    187 	caddr_t addr;
    188 
    189 	/*
    190 	 * Make sure that on error condition we return "no valid mappings."
    191 	 */
    192 	map->dm_mapsize = 0;
    193 	map->dm_nsegs = 0;
    194 
    195 	resid = uio->uio_resid;
    196 	iov = uio->uio_iov;
    197 
    198 	if (uio->uio_segflg == UIO_USERSPACE) {
    199 		p = uio->uio_procp;
    200 #ifdef DIAGNOSTIC
    201 		if (p == NULL)
    202 			panic("integrator_bus_dmamap_load_uio: USERSPACE but no proc");
    203 #endif
    204 	}
    205 
    206 	first = 1;
    207 	seg = 0;
    208 	error = 0;
    209 	for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) {
    210 		/*
    211 		 * Now at the first iovec to load.  Load each iovec
    212 		 * until we have exhausted the residual count.
    213 		 */
    214 		minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len;
    215 		addr = (caddr_t)iov[i].iov_base;
    216 
    217 		error = integrator_bus_dmamap_load_buffer(t, map, addr, minlen,
    218 		    p, flags, &lastaddr, &seg, first);
    219 		first = 0;
    220 
    221 		resid -= minlen;
    222 	}
    223 	if (error == 0) {
    224 		map->dm_mapsize = uio->uio_resid;
    225 		map->dm_nsegs = seg + 1;
    226 		map->_dm_proc = p;
    227 	}
    228 	return (error);
    229 }
    230 
    231 /*
    232  * Common function for DMA-safe memory allocation.  May be called
    233  * by bus-specific DMA memory allocation functions.
    234  */
    235 
    236 extern vm_offset_t physical_start;
    237 extern vm_offset_t physical_freestart;
    238 extern vm_offset_t physical_freeend;
    239 extern vm_offset_t physical_end;
    240 
    241 int
    242 integrator_bus_dmamem_alloc(t, size, alignment, boundary, segs, nsegs, rsegs, flags)
    243 	bus_dma_tag_t t;
    244 	bus_size_t size, alignment, boundary;
    245 	bus_dma_segment_t *segs;
    246 	int nsegs;
    247 	int *rsegs;
    248 	int flags;
    249 {
    250 	int error;
    251 #ifdef DEBUG_DMA
    252 	printf("dmamem_alloc t=%p size=%lx align=%lx boundary=%lx segs=%p nsegs=%x rsegs=%p flags=%x\n",
    253 	    t, size, alignment, boundary, segs, nsegs, rsegs, flags);
    254 #endif	/* DEBUG_DMA */
    255 	error =  (integrator_bus_dmamem_alloc_range(t, size, alignment, boundary,
    256 	    segs, nsegs, rsegs, flags, trunc_page(physical_start), trunc_page(physical_end)));
    257 #ifdef DEBUG_DMA
    258 	printf("dmamem_alloc: =%d\n", error);
    259 #endif	/* DEBUG_DMA */
    260 	return(error);
    261 }
    262 
    263 /*
    264  * Common function for freeing DMA-safe memory.  May be called by
    265  * bus-specific DMA memory free functions.
    266  */
    267 void
    268 integrator_bus_dmamem_free(t, segs, nsegs)
    269 	bus_dma_tag_t t;
    270 	bus_dma_segment_t *segs;
    271 	int nsegs;
    272 {
    273 	struct vm_page *m;
    274 	bus_addr_t addr;
    275 	struct pglist mlist;
    276 	int curseg;
    277 
    278 #ifdef DEBUG_DMA
    279 	printf("dmamem_free: t=%p segs=%p nsegs=%x\n", t, segs, nsegs);
    280 #endif	/* DEBUG_DMA */
    281 
    282 	/*
    283 	 * Build a list of pages to free back to the VM system.
    284 	 */
    285 	TAILQ_INIT(&mlist);
    286 	for (curseg = 0; curseg < nsegs; curseg++) {
    287 		for (addr = segs[curseg].ds_addr;
    288 		    addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
    289 		    addr += PAGE_SIZE) {
    290 			m = PHYS_TO_VM_PAGE(CM_ALIAS_TO_LOCAL(addr));
    291 			TAILQ_INSERT_TAIL(&mlist, m, pageq);
    292 		}
    293 	}
    294 	uvm_pglistfree(&mlist);
    295 }
    296 
    297 /*
    298  * Common function for mapping DMA-safe memory.  May be called by
    299  * bus-specific DMA memory map functions.
    300  */
    301 int
    302 integrator_bus_dmamem_map(t, segs, nsegs, size, kvap, flags)
    303 	bus_dma_tag_t t;
    304 	bus_dma_segment_t *segs;
    305 	int nsegs;
    306 	size_t size;
    307 	caddr_t *kvap;
    308 	int flags;
    309 {
    310 	vm_offset_t va;
    311 	bus_addr_t addr;
    312 	int curseg;
    313 	pt_entry_t *ptep/*, pte*/;
    314 
    315 #ifdef DEBUG_DMA
    316 	printf("dmamem_map: t=%p segs=%p nsegs=%x size=%lx flags=%x\n", t,
    317 	    segs, nsegs, (unsigned long)size, flags);
    318 #endif	/* DEBUG_DMA */
    319 
    320 	size = round_page(size);
    321 	va = uvm_km_valloc(kernel_map, size);
    322 
    323 	if (va == 0)
    324 		return (ENOMEM);
    325 
    326 	*kvap = (caddr_t)va;
    327 
    328 	for (curseg = 0; curseg < nsegs; curseg++) {
    329 		for (addr = segs[curseg].ds_addr;
    330 		    addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
    331 		    addr += NBPG, va += NBPG, size -= NBPG) {
    332 #ifdef DEBUG_DMA
    333 			printf("wiring p%lx to v%lx", CM_ALIAS_TO_LOCAL(addr),
    334 			    va);
    335 #endif	/* DEBUG_DMA */
    336 			if (size == 0)
    337 				panic("integrator_bus_dmamem_map: size botch");
    338 			pmap_enter(pmap_kernel(), va, CM_ALIAS_TO_LOCAL(addr),
    339 			    VM_PROT_READ | VM_PROT_WRITE,
    340 			    VM_PROT_READ | VM_PROT_WRITE | PMAP_WIRED);
    341 			/*
    342 			 * If the memory must remain coherent with the
    343 			 * cache then we must make the memory uncacheable
    344 			 * in order to maintain virtual cache coherency.
    345 			 * We must also guarentee the cache does not already
    346 			 * contain the virtal addresses we are making
    347 			 * uncacheable.
    348 			 */
    349 			if (flags & BUS_DMA_COHERENT) {
    350 				cpu_dcache_wbinv_range(va, NBPG);
    351 				cpu_drain_writebuf();
    352 				ptep = vtopte(va);
    353 				*ptep = ((*ptep) & (~PT_C | PT_B));
    354 				tlb_flush();
    355 			}
    356 #ifdef DEBUG_DMA
    357 			ptep = vtopte(va);
    358 			printf(" pte=v%p *pte=%x\n", ptep, *ptep);
    359 #endif	/* DEBUG_DMA */
    360 		}
    361 	}
    362 	pmap_update(pmap_kernel());
    363 #ifdef DEBUG_DMA
    364 	printf("dmamem_map: =%p\n", *kvap);
    365 #endif	/* DEBUG_DMA */
    366 	return (0);
    367 }
    368 
    369 /*
    370  * Common functin for mmap(2)'ing DMA-safe memory.  May be called by
    371  * bus-specific DMA mmap(2)'ing functions.
    372  */
    373 paddr_t
    374 integrator_bus_dmamem_mmap(t, segs, nsegs, off, prot, flags)
    375 	bus_dma_tag_t t;
    376 	bus_dma_segment_t *segs;
    377 	int nsegs;
    378 	off_t off;
    379 	int prot, flags;
    380 {
    381 	int i;
    382 
    383 	for (i = 0; i < nsegs; i++) {
    384 #ifdef DIAGNOSTIC
    385 		if (off & PGOFSET)
    386 			panic("integrator_bus_dmamem_mmap: offset unaligned");
    387 		if (segs[i].ds_addr & PGOFSET)
    388 			panic("integrator_bus_dmamem_mmap: segment unaligned");
    389 		if (segs[i].ds_len & PGOFSET)
    390 			panic("integrator_bus_dmamem_mmap: segment size not multiple"
    391 			    " of page size");
    392 #endif	/* DIAGNOSTIC */
    393 		if (off >= segs[i].ds_len) {
    394 			off -= segs[i].ds_len;
    395 			continue;
    396 		}
    397 
    398 		return arm_byte_to_page((u_long)CM_ALIAS_TO_LOCAL(segs[i].ds_addr) + off);
    399 	}
    400 
    401 	/* Page not found. */
    402 	return -1;
    403 }
    404 
    405 /**********************************************************************
    406  * DMA utility functions
    407  **********************************************************************/
    408 
    409 /*
    410  * Utility function to load a linear buffer.  lastaddrp holds state
    411  * between invocations (for multiple-buffer loads).  segp contains
    412  * the starting segment on entrace, and the ending segment on exit.
    413  * first indicates if this is the first invocation of this function.
    414  */
    415 static int
    416 integrator_bus_dmamap_load_buffer(t, map, buf, buflen, p, flags, lastaddrp,
    417     segp, first)
    418 	bus_dma_tag_t t;
    419 	bus_dmamap_t map;
    420 	void *buf;
    421 	bus_size_t buflen;
    422 	struct proc *p;
    423 	int flags;
    424 	vm_offset_t *lastaddrp;
    425 	int *segp;
    426 	int first;
    427 {
    428 	bus_size_t sgsize;
    429 	bus_addr_t curaddr, lastaddr, baddr, bmask;
    430 	vm_offset_t vaddr = (vm_offset_t)buf;
    431 	int seg;
    432 	pmap_t pmap;
    433 
    434 #ifdef DEBUG_DMA
    435 	printf("integrator_bus_dmamem_load_buffer(buf=%p, len=%lx, flags=%d, 1st=%d)\n",
    436 	    buf, buflen, flags, first);
    437 #endif	/* DEBUG_DMA */
    438 
    439 	if (p != NULL)
    440 		pmap = p->p_vmspace->vm_map.pmap;
    441 	else
    442 		pmap = pmap_kernel();
    443 
    444 	lastaddr = *lastaddrp;
    445 	bmask  = ~(map->_dm_boundary - 1);
    446 
    447 	for (seg = *segp; buflen > 0; ) {
    448 		/*
    449 		 * Get the physical address for this segment.
    450 		 */
    451 		(void) pmap_extract(pmap, (vaddr_t)vaddr, &curaddr);
    452 
    453 		/*
    454 		 * Make sure we're in an allowed DMA range.
    455 		 */
    456 		if (t->_ranges != NULL &&
    457 		    integrator_bus_dma_inrange(t->_ranges, t->_nranges, curaddr) == 0)
    458 			return (EINVAL);
    459 
    460 		/*
    461 		 * Compute the segment size, and adjust counts.
    462 		 */
    463 		sgsize = NBPG - ((u_long)vaddr & PGOFSET);
    464 		if (buflen < sgsize)
    465 			sgsize = buflen;
    466 
    467 		/*
    468 		 * Make sure we don't cross any boundaries.
    469 		 */
    470 		if (map->_dm_boundary > 0) {
    471 			baddr = (curaddr + map->_dm_boundary) & bmask;
    472 			if (sgsize > (baddr - curaddr))
    473 				sgsize = (baddr - curaddr);
    474 		}
    475 
    476 		/*
    477 		 * Insert chunk into a segment, coalescing with
    478 		 * previous segment if possible.
    479 		 */
    480 		if (first) {
    481 			map->dm_segs[seg].ds_addr = LOCAL_TO_CM_ALIAS(curaddr);
    482 			map->dm_segs[seg].ds_len = sgsize;
    483 			map->dm_segs[seg]._ds_vaddr = vaddr;
    484 			first = 0;
    485 		} else {
    486 			if (curaddr == lastaddr &&
    487 			    (map->dm_segs[seg].ds_len + sgsize) <=
    488 			     map->_dm_maxsegsz &&
    489 			    (map->_dm_boundary == 0 ||
    490 			     (map->dm_segs[seg].ds_addr & bmask) ==
    491 			     (LOCAL_TO_CM_ALIAS(curaddr) & bmask)))
    492 				map->dm_segs[seg].ds_len += sgsize;
    493 			else {
    494 				if (++seg >= map->_dm_segcnt)
    495 					break;
    496 				map->dm_segs[seg].ds_addr = LOCAL_TO_CM_ALIAS(curaddr);
    497 				map->dm_segs[seg].ds_len = sgsize;
    498 				map->dm_segs[seg]._ds_vaddr = vaddr;
    499 			}
    500 		}
    501 
    502 		lastaddr = curaddr + sgsize;
    503 		vaddr += sgsize;
    504 		buflen -= sgsize;
    505 	}
    506 
    507 	*segp = seg;
    508 	*lastaddrp = lastaddr;
    509 
    510 	/*
    511 	 * Did we fit?
    512 	 */
    513 	if (buflen != 0)
    514 		return (EFBIG);		/* XXX better return value here? */
    515 	return (0);
    516 }
    517 
    518 /*
    519  * Check to see if the specified page is in an allowed DMA range.
    520  */
    521 static int
    522 integrator_bus_dma_inrange(ranges, nranges, curaddr)
    523 	bus_dma_segment_t *ranges;
    524 	int nranges;
    525 	bus_addr_t curaddr;
    526 {
    527 	bus_dma_segment_t *ds;
    528 	int i;
    529 
    530 	for (i = 0, ds = ranges; i < nranges; i++, ds++) {
    531 		if (curaddr >= CM_ALIAS_TO_LOCAL(ds->ds_addr) &&
    532 		    round_page(curaddr) <= (CM_ALIAS_TO_LOCAL(ds->ds_addr) + ds->ds_len))
    533 			return (1);
    534 	}
    535 
    536 	return (0);
    537 }
    538 
    539 /*
    540  * Allocate physical memory from the given physical address range.
    541  * Called by DMA-safe memory allocation methods.
    542  */
    543 int
    544 integrator_bus_dmamem_alloc_range(t, size, alignment, boundary, segs, nsegs, rsegs,
    545     flags, low, high)
    546 	bus_dma_tag_t t;
    547 	bus_size_t size, alignment, boundary;
    548 	bus_dma_segment_t *segs;
    549 	int nsegs;
    550 	int *rsegs;
    551 	int flags;
    552 	vm_offset_t low;
    553 	vm_offset_t high;
    554 {
    555 	vm_offset_t curaddr, lastaddr;
    556 	struct vm_page *m;
    557 	struct pglist mlist;
    558 	int curseg, error;
    559 
    560 #ifdef DEBUG_DMA
    561 	printf("alloc_range: t=%p size=%lx align=%lx boundary=%lx segs=%p nsegs=%x rsegs=%p flags=%x lo=%lx hi=%lx\n",
    562 	    t, size, alignment, boundary, segs, nsegs, rsegs, flags, low, high);
    563 #endif	/* DEBUG_DMA */
    564 
    565 	/* Always round the size. */
    566 	size = round_page(size);
    567 
    568 	/*
    569 	 * Allocate pages from the VM system.
    570 	 */
    571 	TAILQ_INIT(&mlist);
    572 	error = uvm_pglistalloc(size, low, high, alignment, boundary,
    573 	    &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0);
    574 	if (error)
    575 		return (error);
    576 
    577 	/*
    578 	 * Compute the location, size, and number of segments actually
    579 	 * returned by the VM code.
    580 	 */
    581 	m = mlist.tqh_first;
    582 	curseg = 0;
    583 	lastaddr = VM_PAGE_TO_PHYS(m);
    584 	segs[curseg].ds_addr = LOCAL_TO_CM_ALIAS(lastaddr);
    585 	segs[curseg].ds_len = PAGE_SIZE;
    586 #ifdef DEBUG_DMA
    587 		printf("alloc: page %lx\n", lastaddr);
    588 #endif	/* DEBUG_DMA */
    589 	m = m->pageq.tqe_next;
    590 
    591 	for (; m != NULL; m = m->pageq.tqe_next) {
    592 		curaddr = VM_PAGE_TO_PHYS(m);
    593 #ifdef DIAGNOSTIC
    594 		if (curaddr < low || curaddr >= high) {
    595 			printf("uvm_pglistalloc returned non-sensical"
    596 			    " address 0x%lx\n", curaddr);
    597 			panic("integrator_bus_dmamem_alloc_range");
    598 		}
    599 #endif	/* DIAGNOSTIC */
    600 #ifdef DEBUG_DMA
    601 		printf("alloc: page %lx\n", curaddr);
    602 #endif	/* DEBUG_DMA */
    603 		if (curaddr == (lastaddr + PAGE_SIZE))
    604 			segs[curseg].ds_len += PAGE_SIZE;
    605 		else {
    606 			curseg++;
    607 			segs[curseg].ds_addr = LOCAL_TO_CM_ALIAS(curaddr);
    608 			segs[curseg].ds_len = PAGE_SIZE;
    609 		}
    610 		lastaddr = curaddr;
    611 	}
    612 
    613 	*rsegs = curseg + 1;
    614 
    615 	return (0);
    616 }
    617