xref: /openbsd-src/sys/arch/arm/arm/bus_dma.c (revision a4a50d9633ad5d32f291ac2e2a431b18d1120b73)
1 /*	$OpenBSD: bus_dma.c,v 1.41 2021/03/25 04:12:00 jsg Exp $	*/
2 /*	$NetBSD: bus_dma.c,v 1.38 2003/10/30 08:44:13 scw Exp $	*/
3 
4 /*-
5  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
6  * All rights reserved.
7  *
8  * This code is derived from software contributed to The NetBSD Foundation
9  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
10  * NASA Ames Research Center.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
23  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
24  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
25  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
26  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
27  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
29  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
30  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
31  * POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #define _ARM32_BUS_DMA_PRIVATE
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/proc.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 
42 #include <uvm/uvm_extern.h>
43 
44 #include <machine/bus.h>
45 #include <arm/cpufunc.h>
46 
47 /*
48  * Common function for DMA map creation.  May be called by bus-specific
49  * DMA map creation functions.
50  */
51 int
_bus_dmamap_create(bus_dma_tag_t t,bus_size_t size,int nsegments,bus_size_t maxsegsz,bus_size_t boundary,int flags,bus_dmamap_t * dmamp)52 _bus_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments,
53     bus_size_t maxsegsz, bus_size_t boundary, int flags, bus_dmamap_t *dmamp)
54 {
55 	struct arm32_bus_dmamap *map;
56 	void *mapstore;
57 	size_t mapsize;
58 
59 #ifdef DEBUG_DMA
60 	printf("dmamap_create: t=%p size=%lx nseg=%x msegsz=%lx boundary=%lx flags=%x\n",
61 	    t, size, nsegments, maxsegsz, boundary, flags);
62 #endif	/* DEBUG_DMA */
63 
64 	/*
65 	 * Allocate and initialize the DMA map.  The end of the map
66 	 * is a variable-sized array of segments, so we allocate enough
67 	 * room for them in one shot.
68 	 *
69 	 * Note we don't preserve the WAITOK or NOWAIT flags.  Preservation
70 	 * of ALLOCNOW notifies others that we've reserved these resources,
71 	 * and they are not to be freed.
72 	 *
73 	 * The bus_dmamap_t includes one bus_dma_segment_t, hence
74 	 * the (nsegments - 1).
75 	 */
76 	mapsize = sizeof(struct arm32_bus_dmamap) +
77 	    (sizeof(bus_dma_segment_t) * (nsegments - 1));
78 	if ((mapstore = malloc(mapsize, M_DEVBUF, (flags & BUS_DMA_NOWAIT) ?
79 	    (M_NOWAIT | M_ZERO) : (M_WAITOK | M_ZERO))) == NULL)
80 		return (ENOMEM);
81 
82 	map = (struct arm32_bus_dmamap *)mapstore;
83 	map->_dm_size = size;
84 	map->_dm_segcnt = nsegments;
85 	map->_dm_maxsegsz = maxsegsz;
86 	map->_dm_boundary = boundary;
87 	map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT);
88 	map->_dm_origbuf = NULL;
89 	map->_dm_buftype = ARM32_BUFTYPE_INVALID;
90 	map->_dm_proc = NULL;
91 	map->dm_mapsize = 0;		/* no valid mappings */
92 	map->dm_nsegs = 0;
93 
94 	*dmamp = map;
95 #ifdef DEBUG_DMA
96 	printf("dmamap_create:map=%p\n", map);
97 #endif	/* DEBUG_DMA */
98 	return (0);
99 }
100 
101 /*
102  * Common function for DMA map destruction.  May be called by bus-specific
103  * DMA map destruction functions.
104  */
105 void
_bus_dmamap_destroy(bus_dma_tag_t t,bus_dmamap_t map)106 _bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
107 {
108 	size_t mapsize;
109 
110 #ifdef DEBUG_DMA
111 	printf("dmamap_destroy: t=%p map=%p\n", t, map);
112 #endif	/* DEBUG_DMA */
113 
114 	mapsize = sizeof(struct arm32_bus_dmamap) +
115 	    (sizeof(bus_dma_segment_t) * (map->_dm_segcnt - 1));
116 	free(map, M_DEVBUF, mapsize);
117 }
118 
119 /*
120  * Common function for loading a DMA map with a linear buffer.  May
121  * be called by bus-specific DMA map load functions.
122  */
123 int
_bus_dmamap_load(bus_dma_tag_t t,bus_dmamap_t map,void * buf,bus_size_t buflen,struct proc * p,int flags)124 _bus_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
125     bus_size_t buflen, struct proc *p, int flags)
126 {
127 	paddr_t lastaddr;
128 	int seg, error;
129 
130 #ifdef DEBUG_DMA
131 	printf("dmamap_load: t=%p map=%p buf=%p len=%lx p=%p f=%d\n",
132 	    t, map, buf, buflen, p, flags);
133 #endif	/* DEBUG_DMA */
134 
135 	/*
136 	 * Make sure that on error condition we return "no valid mappings".
137 	 */
138 	map->dm_mapsize = 0;
139 	map->dm_nsegs = 0;
140 
141 	if (buflen > map->_dm_size)
142 		return (EINVAL);
143 
144 	/* _bus_dmamap_load_buffer() clears this if we're not... */
145 	map->_dm_flags |= ARM32_DMAMAP_COHERENT;
146 
147 	seg = 0;
148 	error = (*t->_dmamap_load_buffer)(t, map, buf, buflen, p, flags,
149 	    &lastaddr, &seg, 1);
150 	if (error == 0) {
151 		map->dm_mapsize = buflen;
152 		map->dm_nsegs = seg + 1;
153 		map->_dm_origbuf = buf;
154 		map->_dm_buftype = ARM32_BUFTYPE_LINEAR;
155 		map->_dm_proc = p;
156 	}
157 #ifdef DEBUG_DMA
158 	printf("dmamap_load: error=%d\n", error);
159 #endif	/* DEBUG_DMA */
160 	return (error);
161 }
162 
163 /*
164  * Like _bus_dmamap_load(), but for mbufs.
165  */
166 int
_bus_dmamap_load_mbuf(bus_dma_tag_t t,bus_dmamap_t map,struct mbuf * m0,int flags)167 _bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map, struct mbuf *m0,
168     int flags)
169 {
170 	paddr_t lastaddr;
171 	int seg, error, first;
172 	struct mbuf *m;
173 
174 #ifdef DEBUG_DMA
175 	printf("dmamap_load_mbuf: t=%p map=%p m0=%p f=%d\n",
176 	    t, map, m0, flags);
177 #endif	/* DEBUG_DMA */
178 
179 	/*
180 	 * Make sure that on error condition we return "no valid mappings."
181 	 */
182 	map->dm_mapsize = 0;
183 	map->dm_nsegs = 0;
184 
185 #ifdef DIAGNOSTIC
186 	if ((m0->m_flags & M_PKTHDR) == 0)
187 		panic("_bus_dmamap_load_mbuf: no packet header");
188 #endif	/* DIAGNOSTIC */
189 
190 	if (m0->m_pkthdr.len > map->_dm_size)
191 		return (EINVAL);
192 
193 	/*
194 	 * Mbuf chains should almost never have coherent (i.e.
195 	 * un-cached) mappings, so clear that flag now.
196 	 */
197 	map->_dm_flags &= ~ARM32_DMAMAP_COHERENT;
198 
199 	first = 1;
200 	seg = 0;
201 	error = 0;
202 	for (m = m0; m != NULL && error == 0; m = m->m_next) {
203 		if (m->m_len == 0)
204 			continue;
205 		error = (*t->_dmamap_load_buffer)(t, map, m->m_data, m->m_len,
206 		    NULL, flags, &lastaddr, &seg, first);
207 		first = 0;
208 	}
209 	if (error == 0) {
210 		map->dm_mapsize = m0->m_pkthdr.len;
211 		map->dm_nsegs = seg + 1;
212 		map->_dm_origbuf = m0;
213 		map->_dm_buftype = ARM32_BUFTYPE_MBUF;
214 		map->_dm_proc = NULL;	/* always kernel */
215 	}
216 #ifdef DEBUG_DMA
217 	printf("dmamap_load_mbuf: error=%d\n", error);
218 #endif	/* DEBUG_DMA */
219 	return (error);
220 }
221 
222 /*
223  * Like _bus_dmamap_load(), but for uios.
224  */
225 int
_bus_dmamap_load_uio(bus_dma_tag_t t,bus_dmamap_t map,struct uio * uio,int flags)226 _bus_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map, struct uio *uio,
227     int flags)
228 {
229 	paddr_t lastaddr;
230 	int seg, i, error, first;
231 	bus_size_t minlen, resid;
232 	struct proc *p = NULL;
233 	struct iovec *iov;
234 	caddr_t addr;
235 
236 	/*
237 	 * Make sure that on error condition we return "no valid mappings."
238 	 */
239 	map->dm_mapsize = 0;
240 	map->dm_nsegs = 0;
241 
242 	resid = uio->uio_resid;
243 	iov = uio->uio_iov;
244 
245 	if (uio->uio_segflg == UIO_USERSPACE) {
246 		p = uio->uio_procp;
247 #ifdef DIAGNOSTIC
248 		if (p == NULL)
249 			panic("_bus_dmamap_load_uio: USERSPACE but no proc");
250 #endif
251 	}
252 
253 	/* _bus_dmamap_load_buffer() clears this if we're not... */
254 	map->_dm_flags |= ARM32_DMAMAP_COHERENT;
255 
256 	first = 1;
257 	seg = 0;
258 	error = 0;
259 	for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) {
260 		/*
261 		 * Now at the first iovec to load.  Load each iovec
262 		 * until we have exhausted the residual count.
263 		 */
264 		minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len;
265 		addr = (caddr_t)iov[i].iov_base;
266 
267 		error = (*t->_dmamap_load_buffer)(t, map, addr, minlen,
268 		    p, flags, &lastaddr, &seg, first);
269 		first = 0;
270 
271 		resid -= minlen;
272 	}
273 	if (error == 0) {
274 		map->dm_mapsize = uio->uio_resid;
275 		map->dm_nsegs = seg + 1;
276 		map->_dm_origbuf = uio;
277 		map->_dm_buftype = ARM32_BUFTYPE_UIO;
278 		map->_dm_proc = p;
279 	}
280 	return (error);
281 }
282 
283 /*
284  * Like _bus_dmamap_load(), but for raw memory allocated with
285  * bus_dmamem_alloc().
286  */
287 int
_bus_dmamap_load_raw(bus_dma_tag_t t,bus_dmamap_t map,bus_dma_segment_t * segs,int nsegs,bus_size_t size,int flags)288 _bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
289     bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
290 {
291 	bus_addr_t paddr, baddr, bmask, lastaddr = 0;
292 	bus_size_t plen, sgsize, mapsize;
293 	vaddr_t vaddr;
294 	int first = 1;
295 	int i, seg = 0;
296 
297 	/*
298 	 * Make sure that on error condition we return "no valid mappings".
299 	 */
300 	map->dm_mapsize = 0;
301 	map->dm_nsegs = 0;
302 
303 	if (nsegs > map->_dm_segcnt || size > map->_dm_size)
304 		return (EINVAL);
305 
306 	mapsize = size;
307 	bmask = ~(map->_dm_boundary - 1);
308 
309 	/*
310 	 * Assume to be coherent at first.  If one of the segments
311 	 * isn't, we clear the flag for the whole map.
312 	 */
313 	map->_dm_flags |= ARM32_DMAMAP_COHERENT;
314 
315 	for (i = 0; i < nsegs && size > 0; i++) {
316 		paddr = segs[i].ds_addr;
317 		vaddr = segs[i]._ds_vaddr;
318 		plen = MIN(segs[i].ds_len, size);
319 
320 		if (!segs[i]._ds_coherent)
321 			map->_dm_flags &= ~ARM32_DMAMAP_COHERENT;
322 
323 		while (plen > 0) {
324 			/*
325 			 * Compute the segment size, and adjust counts.
326 			 */
327 			sgsize = PAGE_SIZE - ((u_long)paddr & PGOFSET);
328 			if (plen < sgsize)
329 				sgsize = plen;
330 
331 			/*
332 			 * Make sure we don't cross any boundaries.
333 			 */
334 			if (map->_dm_boundary > 0) {
335 				baddr = (paddr + map->_dm_boundary) & bmask;
336 				if (sgsize > (baddr - paddr))
337 					sgsize = (baddr - paddr);
338 			}
339 
340 			/*
341 			 * Insert chunk into a segment, coalescing with
342 			 * previous segment if possible.
343 			 */
344 			if (first) {
345 				map->dm_segs[seg].ds_addr = paddr;
346 				map->dm_segs[seg].ds_len = sgsize;
347 				map->dm_segs[seg]._ds_vaddr = vaddr;
348 				first = 0;
349 			} else {
350 				if (paddr == lastaddr &&
351 				    (map->dm_segs[seg].ds_len + sgsize) <=
352 				     map->_dm_maxsegsz &&
353 				    (map->_dm_boundary == 0 ||
354 				     (map->dm_segs[seg].ds_addr & bmask) ==
355 				     (paddr & bmask)))
356 					map->dm_segs[seg].ds_len += sgsize;
357 				else {
358 					if (++seg >= map->_dm_segcnt)
359 						return (EINVAL);
360 					map->dm_segs[seg].ds_addr = paddr;
361 					map->dm_segs[seg].ds_len = sgsize;
362 					map->dm_segs[seg]._ds_vaddr = vaddr;
363 				}
364 			}
365 
366 			paddr += sgsize;
367 			vaddr += sgsize;
368 			plen -= sgsize;
369 			size -= sgsize;
370 
371 			lastaddr = paddr;
372 		}
373 	}
374 
375 	map->dm_mapsize = mapsize;
376 	map->dm_nsegs = seg + 1;
377 	map->_dm_buftype = ARM32_BUFTYPE_RAW;
378 	map->_dm_origbuf = NULL;
379 	map->_dm_proc = NULL;
380 	return (0);
381 }
382 
383 /*
384  * Common function for unloading a DMA map.  May be called by
385  * bus-specific DMA map unload functions.
386  */
387 void
_bus_dmamap_unload(bus_dma_tag_t t,bus_dmamap_t map)388 _bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
389 {
390 
391 #ifdef DEBUG_DMA
392 	printf("dmamap_unload: t=%p map=%p\n", t, map);
393 #endif	/* DEBUG_DMA */
394 
395 	/*
396 	 * No resources to free; just mark the mappings as
397 	 * invalid.
398 	 */
399 	map->dm_mapsize = 0;
400 	map->dm_nsegs = 0;
401 	map->_dm_origbuf = NULL;
402 	map->_dm_buftype = ARM32_BUFTYPE_INVALID;
403 	map->_dm_proc = NULL;
404 }
405 
406 static void
_bus_dmamap_sync_segment(vaddr_t va,paddr_t pa,vsize_t len,int ops)407 _bus_dmamap_sync_segment(vaddr_t va, paddr_t pa, vsize_t len, int ops)
408 {
409 	KASSERT((va & PAGE_MASK) == (pa & PAGE_MASK));
410 
411 #ifdef DEBUG_DMA
412 	printf("sync_segment: va=%#lx pa=%#lx len=%#lx ops=%#x\n",
413 	    va, pa, len, ops);
414 #endif
415 
416 	switch (ops) {
417 	case BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE:
418 		cpu_dcache_wbinv_range(va, len);
419 		cpu_sdcache_wbinv_range(va, pa, len);
420 		break;
421 
422 	case BUS_DMASYNC_PREREAD: {
423 		const size_t line_size = arm_dcache_align;
424 		const size_t line_mask = arm_dcache_align_mask;
425 		vsize_t misalignment = va & line_mask;
426 		if (misalignment) {
427 			va -= misalignment;
428 			pa -= misalignment;
429 			len += misalignment;
430 			cpu_dcache_wbinv_range(va, line_size);
431 			cpu_sdcache_wbinv_range(va, pa, line_size);
432 			if (len <= line_size)
433 				break;
434 			va += line_size;
435 			pa += line_size;
436 			len -= line_size;
437 		}
438 		misalignment = len & line_mask;
439 		len -= misalignment;
440 		if (len > 0) {
441 			cpu_dcache_inv_range(va, len);
442 			cpu_sdcache_inv_range(va, pa, len);
443 		}
444 		if (misalignment) {
445 			va += len;
446 			pa += len;
447 			cpu_dcache_wbinv_range(va, line_size);
448 			cpu_sdcache_wbinv_range(va, pa, line_size);
449 		}
450 		break;
451 	}
452 
453 	case BUS_DMASYNC_PREWRITE:
454 		cpu_dcache_wb_range(va, len);
455 		cpu_sdcache_wb_range(va, pa, len);
456 		break;
457 
458 	/*
459 	 * Cortex CPUs can do speculative loads so we need to clean the cache
460 	 * after a DMA read to deal with any speculatively loaded cache lines.
461 	 * Since these can't be dirty, we can just invalidate them and don't
462 	 * have to worry about having to write back their contents.
463 	 */
464 	case BUS_DMASYNC_POSTREAD:
465 	case BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE:
466 		membar_sync();
467 		cpu_dcache_inv_range(va, len);
468 		cpu_sdcache_inv_range(va, pa, len);
469 		break;
470 	}
471 }
472 
473 static __inline void
_bus_dmamap_sync_linear(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)474 _bus_dmamap_sync_linear(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
475     bus_size_t len, int ops)
476 {
477 	bus_dma_segment_t *ds = map->dm_segs;
478 	vaddr_t va = (vaddr_t) map->_dm_origbuf;
479 
480 	while (len > 0) {
481 		while (offset >= ds->ds_len) {
482 			offset -= ds->ds_len;
483 			va += ds->ds_len;
484 			ds++;
485 		}
486 
487 		paddr_t pa = ds->ds_addr + offset;
488 		size_t seglen = min(len, ds->ds_len - offset);
489 
490 		_bus_dmamap_sync_segment(va + offset, pa, seglen, ops);
491 
492 		offset += seglen;
493 		len -= seglen;
494 	}
495 }
496 
497 static __inline void
_bus_dmamap_sync_mbuf(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)498 _bus_dmamap_sync_mbuf(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
499     bus_size_t len, int ops)
500 {
501 	bus_dma_segment_t *ds = map->dm_segs;
502 	struct mbuf *m = map->_dm_origbuf;
503 	bus_size_t voff = offset;
504 	bus_size_t ds_off = offset;
505 
506 	while (len > 0) {
507 		/* Find the current dma segment */
508 		while (ds_off >= ds->ds_len) {
509 			ds_off -= ds->ds_len;
510 			ds++;
511 		}
512 		/* Find the current mbuf. */
513 		while (voff >= m->m_len) {
514 			voff -= m->m_len;
515 			m = m->m_next;
516 		}
517 
518 		/*
519 		 * Now at the first mbuf to sync; nail each one until
520 		 * we have exhausted the length.
521 		 */
522 		vsize_t seglen = min(len, min(m->m_len - voff, ds->ds_len - ds_off));
523 		vaddr_t va = mtod(m, vaddr_t) + voff;
524 		paddr_t pa = ds->ds_addr + ds_off;
525 
526 		/*
527 		 * We can save a lot of work here if we know the mapping
528 		 * is read-only at the MMU:
529 		 *
530 		 * If a mapping is read-only, no dirty cache blocks will
531 		 * exist for it.  If a writable mapping was made read-only,
532 		 * we know any dirty cache lines for the range will have
533 		 * been cleaned for us already.  Therefore, if the upper
534 		 * layer can tell us we have a read-only mapping, we can
535 		 * skip all cache cleaning.
536 		 *
537 		 * NOTE: This only works if we know the pmap cleans pages
538 		 * before making a read-write -> read-only transition.  If
539 		 * this ever becomes non-true (e.g. Physically Indexed
540 		 * cache), this will have to be revisited.
541 		 */
542 		_bus_dmamap_sync_segment(va, pa, seglen, ops);
543 
544 		voff += seglen;
545 		ds_off += seglen;
546 		len -= seglen;
547 	}
548 }
549 
550 static __inline void
_bus_dmamap_sync_uio(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)551 _bus_dmamap_sync_uio(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
552     bus_size_t len, int ops)
553 {
554 	bus_dma_segment_t *ds = map->dm_segs;
555 	struct uio *uio = map->_dm_origbuf;
556 	struct iovec *iov = uio->uio_iov;
557 	bus_size_t voff = offset;
558 	bus_size_t ds_off = offset;
559 
560 	while (len > 0) {
561 		/* Find the current dma segment */
562 		while (ds_off >= ds->ds_len) {
563 			ds_off -= ds->ds_len;
564 			ds++;
565 		}
566 
567 		/* Find the current iovec. */
568 		while (voff >= iov->iov_len) {
569 			voff -= iov->iov_len;
570 			iov++;
571 		}
572 
573 		/*
574 		 * Now at the first iovec to sync; nail each one until
575 		 * we have exhausted the length.
576 		 */
577 		vsize_t seglen = min(len, min(iov->iov_len - voff, ds->ds_len - ds_off));
578 		vaddr_t va = (vaddr_t) iov->iov_base + voff;
579 		paddr_t pa = ds->ds_addr + ds_off;
580 
581 		_bus_dmamap_sync_segment(va, pa, seglen, ops);
582 
583 		voff += seglen;
584 		ds_off += seglen;
585 		len -= seglen;
586 	}
587 }
588 
589 static __inline void
_bus_dmamap_sync_raw(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)590 _bus_dmamap_sync_raw(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
591     bus_size_t len, int ops)
592 {
593 	bus_dma_segment_t *ds = map->dm_segs;
594 
595 	while (len > 0) {
596 		while (offset >= ds->ds_len) {
597 			offset -= ds->ds_len;
598 			ds++;
599 		}
600 
601 		vaddr_t va = ds->_ds_vaddr + offset;
602 		paddr_t pa = ds->ds_addr + offset;
603 		size_t seglen = min(len, ds->ds_len - offset);
604 
605 		_bus_dmamap_sync_segment(va, pa, seglen, ops);
606 
607 		offset += seglen;
608 		len -= seglen;
609 	}
610 }
611 
612 /*
613  * Common function for DMA map synchronization.  May be called
614  * by bus-specific DMA map synchronization functions.
615  *
616  * This version works for the Virtually Indexed Virtually Tagged
617  * cache found on 32-bit ARM processors.
618  *
619  * XXX Should have separate versions for write-through vs.
620  * XXX write-back caches.  We currently assume write-back
621  * XXX here, which is not as efficient as it could be for
622  * XXX the write-through case.
623  */
624 void
_bus_dmamap_sync(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)625 _bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map, bus_addr_t offset,
626     bus_size_t len, int ops)
627 {
628 
629 #ifdef DEBUG_DMA
630 	printf("dmamap_sync: t=%p map=%p offset=%lx len=%lx ops=%x\n",
631 	    t, map, offset, len, ops);
632 #endif	/* DEBUG_DMA */
633 
634 	/*
635 	 * Mixing of PRE and POST operations is not allowed.
636 	 */
637 	if ((ops & (BUS_DMASYNC_PREREAD|BUS_DMASYNC_PREWRITE)) != 0 &&
638 	    (ops & (BUS_DMASYNC_POSTREAD|BUS_DMASYNC_POSTWRITE)) != 0)
639 		panic("_bus_dmamap_sync: mix PRE and POST");
640 
641 #ifdef DIAGNOSTIC
642 	if (offset >= map->dm_mapsize)
643 		panic("_bus_dmamap_sync: bad offset %lu (map size is %lu)",
644 		    offset, map->dm_mapsize);
645 	if ((offset + len) > map->dm_mapsize)
646 		panic("_bus_dmamap_sync: bad length");
647 #endif
648 
649 	/*
650 	 * For a virtually-indexed write-back cache, we need
651 	 * to do the following things:
652 	 *
653 	 *	PREREAD -- Invalidate the D-cache.  We do this
654 	 *	here in case a write-back is required by the back-end.
655 	 *
656 	 *	PREWRITE -- Write-back the D-cache.  Note that if
657 	 *	we are doing a PREREAD|PREWRITE, we can collapse
658 	 *	the whole thing into a single Wb-Inv.
659 	 *
660 	 *	POSTREAD -- Invalidate the D-Cache. Contents of
661 	 *	the cache could be from before a device wrote
662 	 *	to the memory.
663 	 *
664 	 *	POSTWRITE -- Nothing.
665 	 */
666 
667 	/* Skip cache frobbing if mapping was COHERENT. */
668 	if (map->_dm_flags & ARM32_DMAMAP_COHERENT) {
669 		/* Drain the write buffer. */
670 		cpu_drain_writebuf();
671 		cpu_sdcache_drain_writebuf();
672 		return;
673 	}
674 
675 	/*
676 	 * If the mapping belongs to a non-kernel vmspace, and the
677 	 * vmspace has not been active since the last time a full
678 	 * cache flush was performed, we don't need to do anything.
679 	 */
680 	if (__predict_false(map->_dm_proc != NULL &&
681 	    map->_dm_proc->p_vmspace->vm_map.pmap->pm_cstate.cs_cache_d == 0))
682 		return;
683 
684 	switch (map->_dm_buftype) {
685 	case ARM32_BUFTYPE_LINEAR:
686 		_bus_dmamap_sync_linear(t, map, offset, len, ops);
687 		break;
688 
689 	case ARM32_BUFTYPE_MBUF:
690 		_bus_dmamap_sync_mbuf(t, map, offset, len, ops);
691 		break;
692 
693 	case ARM32_BUFTYPE_UIO:
694 		_bus_dmamap_sync_uio(t, map, offset, len, ops);
695 		break;
696 
697 	case ARM32_BUFTYPE_RAW:
698 		_bus_dmamap_sync_raw(t, map, offset, len, ops);
699 		break;
700 
701 	case ARM32_BUFTYPE_INVALID:
702 		panic("_bus_dmamap_sync: ARM32_BUFTYPE_INVALID");
703 		break;
704 
705 	default:
706 		printf("unknown buffer type %d\n", map->_dm_buftype);
707 		panic("_bus_dmamap_sync");
708 	}
709 
710 	/* Drain the write buffer. */
711 	cpu_drain_writebuf();
712 }
713 
714 /*
715  * Common function for DMA-safe memory allocation.  May be called
716  * by bus-specific DMA memory allocation functions.
717  */
718 
719 int
_bus_dmamem_alloc(bus_dma_tag_t t,bus_size_t size,bus_size_t alignment,bus_size_t boundary,bus_dma_segment_t * segs,int nsegs,int * rsegs,int flags)720 _bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment,
721     bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
722     int flags)
723 {
724 	int error;
725 
726 #ifdef DEBUG_DMA
727 	printf("dmamem_alloc t=%p size=%lx align=%lx boundary=%lx "
728 	    "segs=%p nsegs=%x rsegs=%p flags=%x\n", t, size, alignment,
729 	    boundary, segs, nsegs, rsegs, flags);
730 #endif
731 
732 	error = _bus_dmamem_alloc_range(t, size, alignment, boundary,
733 	    segs, nsegs, rsegs, flags, 0, -1);
734 
735 #ifdef DEBUG_DMA
736 	printf("dmamem_alloc: =%d\n", error);
737 #endif
738 
739 	return(error);
740 }
741 
742 /*
743  * Common function for freeing DMA-safe memory.  May be called by
744  * bus-specific DMA memory free functions.
745  */
746 void
_bus_dmamem_free(bus_dma_tag_t t,bus_dma_segment_t * segs,int nsegs)747 _bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs)
748 {
749 	struct vm_page *m;
750 	bus_addr_t addr;
751 	struct pglist mlist;
752 	int curseg;
753 
754 #ifdef DEBUG_DMA
755 	printf("dmamem_free: t=%p segs=%p nsegs=%x\n", t, segs, nsegs);
756 #endif	/* DEBUG_DMA */
757 
758 	/*
759 	 * Build a list of pages to free back to the VM system.
760 	 */
761 	TAILQ_INIT(&mlist);
762 	for (curseg = 0; curseg < nsegs; curseg++) {
763 		for (addr = segs[curseg].ds_addr;
764 		    addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
765 		    addr += PAGE_SIZE) {
766 			m = PHYS_TO_VM_PAGE(addr);
767 			TAILQ_INSERT_TAIL(&mlist, m, pageq);
768 		}
769 	}
770 	uvm_pglistfree(&mlist);
771 }
772 
773 /*
774  * Common function for mapping DMA-safe memory.  May be called by
775  * bus-specific DMA memory map functions.
776  */
777 int
_bus_dmamem_map(bus_dma_tag_t t,bus_dma_segment_t * segs,int nsegs,size_t size,caddr_t * kvap,int flags)778 _bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
779     size_t size, caddr_t *kvap, int flags)
780 {
781 	vaddr_t va, sva;
782 	size_t ssize;
783 	bus_addr_t addr;
784 	int curseg;
785 	const struct kmem_dyn_mode *kd;
786 #ifdef DEBUG_DMA
787 	pt_entry_t *ptep;
788 #endif
789 
790 #ifdef DEBUG_DMA
791 	printf("dmamem_map: t=%p segs=%p nsegs=%x size=%lx flags=%x\n", t,
792 	    segs, nsegs, (unsigned long)size, flags);
793 #endif	/* DEBUG_DMA */
794 
795 	size = round_page(size);
796 	kd = flags & BUS_DMA_NOWAIT ? &kd_trylock : &kd_waitok;
797 	va = (vaddr_t)km_alloc(size, &kv_any, &kp_none, kd);
798 	if (va == 0)
799 		return (ENOMEM);
800 
801 	*kvap = (caddr_t)va;
802 
803 	sva = va;
804 	ssize = size;
805 	for (curseg = 0; curseg < nsegs; curseg++) {
806 		for (addr = segs[curseg].ds_addr;
807 		    addr < (segs[curseg].ds_addr + segs[curseg].ds_len);
808 		    addr += PAGE_SIZE, va += PAGE_SIZE, size -= PAGE_SIZE) {
809 #ifdef DEBUG_DMA
810 			printf("wiring p%lx to v%lx", addr, va);
811 #endif	/* DEBUG_DMA */
812 			if (size == 0)
813 				panic("_bus_dmamem_map: size botch");
814 			segs[curseg]._ds_coherent =
815 			    !!(flags & BUS_DMA_COHERENT);
816 			segs[curseg]._ds_vaddr = va;
817 			pmap_kenter_cache(va, addr,
818 			    PROT_READ | PROT_WRITE,
819 			    !(flags & BUS_DMA_COHERENT));
820 
821 #ifdef DEBUG_DMA
822 			ptep = vtopte(va);
823 			printf(" pte=v%p *pte=%x\n", ptep, *ptep);
824 #endif	/* DEBUG_DMA */
825 		}
826 	}
827 	pmap_update(pmap_kernel());
828 #ifdef DEBUG_DMA
829 	printf("dmamem_map: =%p\n", *kvap);
830 #endif	/* DEBUG_DMA */
831 	return (0);
832 }
833 
834 /*
835  * Common function for unmapping DMA-safe memory.  May be called by
836  * bus-specific DMA memory unmapping functions.
837  */
838 void
_bus_dmamem_unmap(bus_dma_tag_t t,caddr_t kva,size_t size)839 _bus_dmamem_unmap(bus_dma_tag_t t, caddr_t kva, size_t size)
840 {
841 
842 #ifdef DEBUG_DMA
843 	printf("dmamem_unmap: t=%p kva=%p size=%lx\n", t, kva,
844 	    (unsigned long)size);
845 #endif	/* DEBUG_DMA */
846 #ifdef DIAGNOSTIC
847 	if ((u_long)kva & PGOFSET)
848 		panic("_bus_dmamem_unmap");
849 #endif	/* DIAGNOSTIC */
850 
851 	km_free(kva, round_page(size), &kv_any, &kp_none);
852 }
853 
854 /*
855  * Common function for mmap(2)'ing DMA-safe memory.  May be called by
856  * bus-specific DMA mmap(2)'ing functions.
857  */
858 paddr_t
_bus_dmamem_mmap(bus_dma_tag_t t,bus_dma_segment_t * segs,int nsegs,off_t off,int prot,int flags)859 _bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
860     off_t off, int prot, int flags)
861 {
862 	int i;
863 
864 	for (i = 0; i < nsegs; i++) {
865 #ifdef DIAGNOSTIC
866 		if (off & PGOFSET)
867 			panic("_bus_dmamem_mmap: offset unaligned");
868 		if (segs[i].ds_addr & PGOFSET)
869 			panic("_bus_dmamem_mmap: segment unaligned");
870 		if (segs[i].ds_len & PGOFSET)
871 			panic("_bus_dmamem_mmap: segment size not multiple"
872 			    " of page size");
873 #endif	/* DIAGNOSTIC */
874 		if (off >= segs[i].ds_len) {
875 			off -= segs[i].ds_len;
876 			continue;
877 		}
878 
879 		return (segs[i].ds_addr + off);
880 	}
881 
882 	/* Page not found. */
883 	return (-1);
884 }
885 
886 /**********************************************************************
887  * DMA utility functions
888  **********************************************************************/
889 
890 /*
891  * Utility function to load a linear buffer.  lastaddrp holds state
892  * between invocations (for multiple-buffer loads).  segp contains
893  * the starting segment on entrance, and the ending segment on exit.
894  * first indicates if this is the first invocation of this function.
895  */
896 int
_bus_dmamap_load_buffer(bus_dma_tag_t t,bus_dmamap_t map,void * buf,bus_size_t buflen,struct proc * p,int flags,paddr_t * lastaddrp,int * segp,int first)897 _bus_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map, void *buf,
898     bus_size_t buflen, struct proc *p, int flags, paddr_t *lastaddrp,
899     int *segp, int first)
900 {
901 	bus_size_t sgsize;
902 	bus_addr_t curaddr, lastaddr, baddr, bmask;
903 	vaddr_t vaddr = (vaddr_t)buf;
904 	pd_entry_t *pde;
905 	pt_entry_t pte;
906 	int seg;
907 	pmap_t pmap;
908 	pt_entry_t *ptep;
909 
910 #ifdef DEBUG_DMA
911 	printf("_bus_dmamem_load_buffer(buf=%p, len=%lx, flags=%d, 1st=%d)\n",
912 	    buf, buflen, flags, first);
913 #endif	/* DEBUG_DMA */
914 
915 	if (p != NULL)
916 		pmap = p->p_vmspace->vm_map.pmap;
917 	else
918 		pmap = pmap_kernel();
919 
920 	lastaddr = *lastaddrp;
921 	bmask  = ~(map->_dm_boundary - 1);
922 
923 	for (seg = *segp; buflen > 0; ) {
924 		/*
925 		 * Get the physical address for this segment.
926 		 *
927 		 * XXX Don't support checking for coherent mappings
928 		 * XXX in user address space.
929 		 */
930 		if (__predict_true(pmap == pmap_kernel())) {
931 			(void) pmap_get_pde_pte(pmap, vaddr, &pde, &ptep);
932 			if (__predict_false(pmap_pde_section(pde))) {
933 				curaddr = (*pde & L1_S_FRAME) |
934 				    (vaddr & L1_S_OFFSET);
935 				if (*pde & L1_S_COHERENT) {
936 					map->_dm_flags &=
937 					    ~ARM32_DMAMAP_COHERENT;
938 				}
939 			} else {
940 				pte = *ptep;
941 				KDASSERT((pte & L2_TYPE_MASK) != L2_TYPE_INV);
942 				if (__predict_false((pte & L2_TYPE_MASK)
943 						    == L2_TYPE_L)) {
944 					curaddr = (pte & L2_L_FRAME) |
945 					    (vaddr & L2_L_OFFSET);
946 					if (pte & L2_L_COHERENT) {
947 						map->_dm_flags &=
948 						    ~ARM32_DMAMAP_COHERENT;
949 					}
950 				} else {
951 					curaddr = (pte & L2_S_FRAME) |
952 					    (vaddr & L2_S_OFFSET);
953 					if (pte & L2_S_COHERENT) {
954 						map->_dm_flags &=
955 						    ~ARM32_DMAMAP_COHERENT;
956 					}
957 				}
958 			}
959 		} else {
960 			(void) pmap_extract(pmap, vaddr, &curaddr);
961 			map->_dm_flags &= ~ARM32_DMAMAP_COHERENT;
962 		}
963 
964 		/*
965 		 * Compute the segment size, and adjust counts.
966 		 */
967 		sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET);
968 		if (buflen < sgsize)
969 			sgsize = buflen;
970 
971 		/*
972 		 * Make sure we don't cross any boundaries.
973 		 */
974 		if (map->_dm_boundary > 0) {
975 			baddr = (curaddr + map->_dm_boundary) & bmask;
976 			if (sgsize > (baddr - curaddr))
977 				sgsize = (baddr - curaddr);
978 		}
979 
980 		/*
981 		 * Insert chunk into a segment, coalescing with
982 		 * previous segment if possible.
983 		 */
984 		if (first) {
985 			map->dm_segs[seg].ds_addr = curaddr;
986 			map->dm_segs[seg].ds_len = sgsize;
987 			first = 0;
988 		} else {
989 			if (curaddr == lastaddr &&
990 			    (map->dm_segs[seg].ds_len + sgsize) <=
991 			     map->_dm_maxsegsz &&
992 			    (map->_dm_boundary == 0 ||
993 			     (map->dm_segs[seg].ds_addr & bmask) ==
994 			     (curaddr & bmask)))
995 				map->dm_segs[seg].ds_len += sgsize;
996 			else {
997 				if (++seg >= map->_dm_segcnt)
998 					break;
999 				map->dm_segs[seg].ds_addr = curaddr;
1000 				map->dm_segs[seg].ds_len = sgsize;
1001 			}
1002 		}
1003 
1004 		lastaddr = curaddr + sgsize;
1005 		vaddr += sgsize;
1006 		buflen -= sgsize;
1007 	}
1008 
1009 	*segp = seg;
1010 	*lastaddrp = lastaddr;
1011 
1012 	/*
1013 	 * Did we fit?
1014 	 */
1015 	if (buflen != 0)
1016 		return (EFBIG);		/* XXX better return value here? */
1017 	return (0);
1018 }
1019 
1020 /*
1021  * Allocate physical memory from the given physical address range.
1022  * Called by DMA-safe memory allocation methods.
1023  */
1024 int
_bus_dmamem_alloc_range(bus_dma_tag_t t,bus_size_t size,bus_size_t alignment,bus_size_t boundary,bus_dma_segment_t * segs,int nsegs,int * rsegs,int flags,paddr_t low,paddr_t high)1025 _bus_dmamem_alloc_range(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment,
1026     bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
1027     int flags, paddr_t low, paddr_t high)
1028 {
1029 	paddr_t curaddr, lastaddr;
1030 	struct vm_page *m;
1031 	struct pglist mlist;
1032 	int curseg, error, plaflag;
1033 
1034 #ifdef DEBUG_DMA
1035 	printf("alloc_range: t=%p size=%lx align=%lx boundary=%lx segs=%p nsegs=%x rsegs=%p flags=%x lo=%lx hi=%lx\n",
1036 	    t, size, alignment, boundary, segs, nsegs, rsegs, flags, low, high);
1037 #endif	/* DEBUG_DMA */
1038 
1039 	/* Always round the size. */
1040 	size = round_page(size);
1041 
1042 	/*
1043 	 * Allocate pages from the VM system.
1044 	 */
1045 	plaflag = flags & BUS_DMA_NOWAIT ? UVM_PLA_NOWAIT : UVM_PLA_WAITOK;
1046 	if (flags & BUS_DMA_ZERO)
1047 		plaflag |= UVM_PLA_ZERO;
1048 
1049 	TAILQ_INIT(&mlist);
1050 	error = uvm_pglistalloc(size, low, high, alignment, boundary,
1051 	    &mlist, nsegs, plaflag);
1052 	if (error)
1053 		return (error);
1054 
1055 	/*
1056 	 * Compute the location, size, and number of segments actually
1057 	 * returned by the VM code.
1058 	 */
1059 	m = TAILQ_FIRST(&mlist);
1060 	curseg = 0;
1061 	lastaddr = segs[curseg].ds_addr = VM_PAGE_TO_PHYS(m);
1062 	segs[curseg].ds_len = PAGE_SIZE;
1063 #ifdef DEBUG_DMA
1064 		printf("alloc: page %lx\n", lastaddr);
1065 #endif	/* DEBUG_DMA */
1066 	m = TAILQ_NEXT(m, pageq);
1067 
1068 	for (; m != NULL; m = TAILQ_NEXT(m, pageq)) {
1069 		curaddr = VM_PAGE_TO_PHYS(m);
1070 #ifdef DIAGNOSTIC
1071 		if (curaddr < low || curaddr >= high) {
1072 			printf("uvm_pglistalloc returned non-sensical"
1073 			    " address 0x%lx\n", curaddr);
1074 			panic("_bus_dmamem_alloc_range");
1075 		}
1076 #endif	/* DIAGNOSTIC */
1077 #ifdef DEBUG_DMA
1078 		printf("alloc: page %lx\n", curaddr);
1079 #endif	/* DEBUG_DMA */
1080 		if (curaddr == (lastaddr + PAGE_SIZE))
1081 			segs[curseg].ds_len += PAGE_SIZE;
1082 		else {
1083 			curseg++;
1084 			segs[curseg].ds_addr = curaddr;
1085 			segs[curseg].ds_len = PAGE_SIZE;
1086 		}
1087 		lastaddr = curaddr;
1088 	}
1089 
1090 	*rsegs = curseg + 1;
1091 
1092 	return (0);
1093 }
1094 
1095 /*
1096  * probably should be ppc_space_copy
1097  */
1098 
1099 #define _CONCAT(A,B) A ## B
1100 #define __C(A,B)	_CONCAT(A,B)
1101 
1102 #define BUS_SPACE_READ_RAW_MULTI_N(BYTES,SHIFT,TYPE)			\
1103 void									\
1104 __C(bus_space_read_raw_multi_,BYTES)(bus_space_tag_t bst,		\
1105     bus_space_handle_t h, bus_addr_t o, u_int8_t *dst, bus_size_t size)	\
1106 {									\
1107 	TYPE *rdst = (TYPE *)dst;					\
1108 	int i;								\
1109 	int count = size >> SHIFT;					\
1110 									\
1111 	for (i = 0; i < count; i++) {					\
1112 		rdst[i] = __bs_rs(BYTES, bst, h, o);			\
1113 	}								\
1114 }
1115 BUS_SPACE_READ_RAW_MULTI_N(2,1,u_int16_t)
1116 BUS_SPACE_READ_RAW_MULTI_N(4,2,u_int32_t)
1117 
1118 #define BUS_SPACE_WRITE_RAW_MULTI_N(BYTES,SHIFT,TYPE)			\
1119 void									\
1120 __C(bus_space_write_raw_multi_,BYTES)( bus_space_tag_t bst,		\
1121     bus_space_handle_t h, bus_addr_t o, const u_int8_t *src,		\
1122     bus_size_t size)							\
1123 {									\
1124 	int i;								\
1125 	TYPE *rsrc = (TYPE *)src;					\
1126 	int count = size >> SHIFT;					\
1127 									\
1128 	for (i = 0; i < count; i++) {					\
1129 		__bs_ws(BYTES, bst, h, o, rsrc[i]);			\
1130 	}								\
1131 }
1132 
1133 BUS_SPACE_WRITE_RAW_MULTI_N(2,1,u_int16_t)
1134 BUS_SPACE_WRITE_RAW_MULTI_N(4,2,u_int32_t)
1135