xref: /freebsd/sys/dev/usb/usb_busdma.c (revision d4ae33f0721c1b170fe37d97e395228ffcfb3f80)
1 /* $FreeBSD$ */
2 /*-
3  * Copyright (c) 2008 Hans Petter Selasky. All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #ifdef USB_GLOBAL_INCLUDE_FILE
28 #include USB_GLOBAL_INCLUDE_FILE
29 #else
30 #include <sys/stdint.h>
31 #include <sys/stddef.h>
32 #include <sys/param.h>
33 #include <sys/queue.h>
34 #include <sys/types.h>
35 #include <sys/systm.h>
36 #include <sys/kernel.h>
37 #include <sys/bus.h>
38 #include <sys/module.h>
39 #include <sys/lock.h>
40 #include <sys/mutex.h>
41 #include <sys/condvar.h>
42 #include <sys/sysctl.h>
43 #include <sys/sx.h>
44 #include <sys/unistd.h>
45 #include <sys/callout.h>
46 #include <sys/malloc.h>
47 #include <sys/priv.h>
48 
49 #include <dev/usb/usb.h>
50 #include <dev/usb/usbdi.h>
51 #include <dev/usb/usbdi_util.h>
52 
53 #define	USB_DEBUG_VAR usb_debug
54 
55 #include <dev/usb/usb_core.h>
56 #include <dev/usb/usb_busdma.h>
57 #include <dev/usb/usb_process.h>
58 #include <dev/usb/usb_transfer.h>
59 #include <dev/usb/usb_device.h>
60 #include <dev/usb/usb_util.h>
61 #include <dev/usb/usb_debug.h>
62 
63 #include <dev/usb/usb_controller.h>
64 #include <dev/usb/usb_bus.h>
65 #endif			/* USB_GLOBAL_INCLUDE_FILE */
66 
67 #if USB_HAVE_BUSDMA
68 static void	usb_dma_tag_create(struct usb_dma_tag *, usb_size_t, usb_size_t);
69 static void	usb_dma_tag_destroy(struct usb_dma_tag *);
70 static void	usb_dma_lock_cb(void *, bus_dma_lock_op_t);
71 static void	usb_pc_alloc_mem_cb(void *, bus_dma_segment_t *, int, int);
72 static void	usb_pc_load_mem_cb(void *, bus_dma_segment_t *, int, int);
73 static void	usb_pc_common_mem_cb(void *, bus_dma_segment_t *, int, int,
74 		    uint8_t);
75 #endif
76 
77 /*------------------------------------------------------------------------*
78  *  usbd_get_page - lookup DMA-able memory for the given offset
79  *
80  * NOTE: Only call this function when the "page_cache" structure has
81  * been properly initialized !
82  *------------------------------------------------------------------------*/
83 void
84 usbd_get_page(struct usb_page_cache *pc, usb_frlength_t offset,
85     struct usb_page_search *res)
86 {
87 #if USB_HAVE_BUSDMA
88 	struct usb_page *page;
89 
90 	if (pc->page_start) {
91 
92 		/* Case 1 - something has been loaded into DMA */
93 
94 		if (pc->buffer) {
95 
96 			/* Case 1a - Kernel Virtual Address */
97 
98 			res->buffer = USB_ADD_BYTES(pc->buffer, offset);
99 		}
100 		offset += pc->page_offset_buf;
101 
102 		/* compute destination page */
103 
104 		page = pc->page_start;
105 
106 		if (pc->ismultiseg) {
107 
108 			page += (offset / USB_PAGE_SIZE);
109 
110 			offset %= USB_PAGE_SIZE;
111 
112 			res->length = USB_PAGE_SIZE - offset;
113 			res->physaddr = page->physaddr + offset;
114 		} else {
115 			res->length = (usb_size_t)-1;
116 			res->physaddr = page->physaddr + offset;
117 		}
118 		if (!pc->buffer) {
119 
120 			/* Case 1b - Non Kernel Virtual Address */
121 
122 			res->buffer = USB_ADD_BYTES(page->buffer, offset);
123 		}
124 		return;
125 	}
126 #endif
127 	/* Case 2 - Plain PIO */
128 
129 	res->buffer = USB_ADD_BYTES(pc->buffer, offset);
130 	res->length = (usb_size_t)-1;
131 #if USB_HAVE_BUSDMA
132 	res->physaddr = 0;
133 #endif
134 }
135 
136 /*------------------------------------------------------------------------*
137  *  usbd_copy_in - copy directly to DMA-able memory
138  *------------------------------------------------------------------------*/
139 void
140 usbd_copy_in(struct usb_page_cache *cache, usb_frlength_t offset,
141     const void *ptr, usb_frlength_t len)
142 {
143 	struct usb_page_search buf_res;
144 
145 	while (len != 0) {
146 
147 		usbd_get_page(cache, offset, &buf_res);
148 
149 		if (buf_res.length > len) {
150 			buf_res.length = len;
151 		}
152 		memcpy(buf_res.buffer, ptr, buf_res.length);
153 
154 		offset += buf_res.length;
155 		len -= buf_res.length;
156 		ptr = USB_ADD_BYTES(ptr, buf_res.length);
157 	}
158 }
159 
160 /*------------------------------------------------------------------------*
161  *  usbd_copy_in_user - copy directly to DMA-able memory from userland
162  *
163  * Return values:
164  *    0: Success
165  * Else: Failure
166  *------------------------------------------------------------------------*/
167 #if USB_HAVE_USER_IO
168 int
169 usbd_copy_in_user(struct usb_page_cache *cache, usb_frlength_t offset,
170     const void *ptr, usb_frlength_t len)
171 {
172 	struct usb_page_search buf_res;
173 	int error;
174 
175 	while (len != 0) {
176 
177 		usbd_get_page(cache, offset, &buf_res);
178 
179 		if (buf_res.length > len) {
180 			buf_res.length = len;
181 		}
182 		error = copyin(ptr, buf_res.buffer, buf_res.length);
183 		if (error)
184 			return (error);
185 
186 		offset += buf_res.length;
187 		len -= buf_res.length;
188 		ptr = USB_ADD_BYTES(ptr, buf_res.length);
189 	}
190 	return (0);			/* success */
191 }
192 #endif
193 
194 /*------------------------------------------------------------------------*
195  *  usbd_m_copy_in - copy a mbuf chain directly into DMA-able memory
196  *------------------------------------------------------------------------*/
197 #if USB_HAVE_MBUF
198 struct usb_m_copy_in_arg {
199 	struct usb_page_cache *cache;
200 	usb_frlength_t dst_offset;
201 };
202 
203 static int
204 usbd_m_copy_in_cb(void *arg, void *src, uint32_t count)
205 {
206 	register struct usb_m_copy_in_arg *ua = arg;
207 
208 	usbd_copy_in(ua->cache, ua->dst_offset, src, count);
209 	ua->dst_offset += count;
210 	return (0);
211 }
212 
213 void
214 usbd_m_copy_in(struct usb_page_cache *cache, usb_frlength_t dst_offset,
215     struct mbuf *m, usb_size_t src_offset, usb_frlength_t src_len)
216 {
217 	struct usb_m_copy_in_arg arg = {cache, dst_offset};
218 	(void) m_apply(m, src_offset, src_len, &usbd_m_copy_in_cb, &arg);
219 }
220 #endif
221 
222 /*------------------------------------------------------------------------*
223  *  usb_uiomove - factored out code
224  *------------------------------------------------------------------------*/
225 #if USB_HAVE_USER_IO
226 int
227 usb_uiomove(struct usb_page_cache *pc, struct uio *uio,
228     usb_frlength_t pc_offset, usb_frlength_t len)
229 {
230 	struct usb_page_search res;
231 	int error = 0;
232 
233 	while (len != 0) {
234 
235 		usbd_get_page(pc, pc_offset, &res);
236 
237 		if (res.length > len) {
238 			res.length = len;
239 		}
240 		/*
241 		 * "uiomove()" can sleep so one needs to make a wrapper,
242 		 * exiting the mutex and checking things
243 		 */
244 		error = uiomove(res.buffer, res.length, uio);
245 
246 		if (error) {
247 			break;
248 		}
249 		pc_offset += res.length;
250 		len -= res.length;
251 	}
252 	return (error);
253 }
254 #endif
255 
256 /*------------------------------------------------------------------------*
257  *  usbd_copy_out - copy directly from DMA-able memory
258  *------------------------------------------------------------------------*/
259 void
260 usbd_copy_out(struct usb_page_cache *cache, usb_frlength_t offset,
261     void *ptr, usb_frlength_t len)
262 {
263 	struct usb_page_search res;
264 
265 	while (len != 0) {
266 
267 		usbd_get_page(cache, offset, &res);
268 
269 		if (res.length > len) {
270 			res.length = len;
271 		}
272 		memcpy(ptr, res.buffer, res.length);
273 
274 		offset += res.length;
275 		len -= res.length;
276 		ptr = USB_ADD_BYTES(ptr, res.length);
277 	}
278 }
279 
280 /*------------------------------------------------------------------------*
281  *  usbd_copy_out_user - copy directly from DMA-able memory to userland
282  *
283  * Return values:
284  *    0: Success
285  * Else: Failure
286  *------------------------------------------------------------------------*/
287 #if USB_HAVE_USER_IO
288 int
289 usbd_copy_out_user(struct usb_page_cache *cache, usb_frlength_t offset,
290     void *ptr, usb_frlength_t len)
291 {
292 	struct usb_page_search res;
293 	int error;
294 
295 	while (len != 0) {
296 
297 		usbd_get_page(cache, offset, &res);
298 
299 		if (res.length > len) {
300 			res.length = len;
301 		}
302 		error = copyout(res.buffer, ptr, res.length);
303 		if (error)
304 			return (error);
305 
306 		offset += res.length;
307 		len -= res.length;
308 		ptr = USB_ADD_BYTES(ptr, res.length);
309 	}
310 	return (0);			/* success */
311 }
312 #endif
313 
314 /*------------------------------------------------------------------------*
315  *  usbd_frame_zero - zero DMA-able memory
316  *------------------------------------------------------------------------*/
317 void
318 usbd_frame_zero(struct usb_page_cache *cache, usb_frlength_t offset,
319     usb_frlength_t len)
320 {
321 	struct usb_page_search res;
322 
323 	while (len != 0) {
324 
325 		usbd_get_page(cache, offset, &res);
326 
327 		if (res.length > len) {
328 			res.length = len;
329 		}
330 		memset(res.buffer, 0, res.length);
331 
332 		offset += res.length;
333 		len -= res.length;
334 	}
335 }
336 
337 #if USB_HAVE_BUSDMA
338 
339 /*------------------------------------------------------------------------*
340  *	usb_dma_lock_cb - dummy callback
341  *------------------------------------------------------------------------*/
342 static void
343 usb_dma_lock_cb(void *arg, bus_dma_lock_op_t op)
344 {
345 	/* we use "mtx_owned()" instead of this function */
346 }
347 
348 /*------------------------------------------------------------------------*
349  *	usb_dma_tag_create - allocate a DMA tag
350  *
351  * NOTE: If the "align" parameter has a value of 1 the DMA-tag will
352  * allow multi-segment mappings. Else all mappings are single-segment.
353  *------------------------------------------------------------------------*/
354 static void
355 usb_dma_tag_create(struct usb_dma_tag *udt,
356     usb_size_t size, usb_size_t align)
357 {
358 	bus_dma_tag_t tag;
359 
360 	if (bus_dma_tag_create
361 	    ( /* parent    */ udt->tag_parent->tag,
362 	     /* alignment */ align,
363 	     /* boundary  */ 0,
364 	     /* lowaddr   */ (2ULL << (udt->tag_parent->dma_bits - 1)) - 1,
365 	     /* highaddr  */ BUS_SPACE_MAXADDR,
366 	     /* filter    */ NULL,
367 	     /* filterarg */ NULL,
368 	     /* maxsize   */ size,
369 	     /* nsegments */ (align == 1 && size > 1) ?
370 	    (2 + (size / USB_PAGE_SIZE)) : 1,
371 	     /* maxsegsz  */ (align == 1 && size > USB_PAGE_SIZE) ?
372 	    USB_PAGE_SIZE : size,
373 	     /* flags     */ BUS_DMA_KEEP_PG_OFFSET,
374 	     /* lockfn    */ &usb_dma_lock_cb,
375 	     /* lockarg   */ NULL,
376 	    &tag)) {
377 		tag = NULL;
378 	}
379 	udt->tag = tag;
380 }
381 
382 /*------------------------------------------------------------------------*
383  *	usb_dma_tag_free - free a DMA tag
384  *------------------------------------------------------------------------*/
385 static void
386 usb_dma_tag_destroy(struct usb_dma_tag *udt)
387 {
388 	bus_dma_tag_destroy(udt->tag);
389 }
390 
391 /*------------------------------------------------------------------------*
392  *	usb_pc_alloc_mem_cb - BUS-DMA callback function
393  *------------------------------------------------------------------------*/
394 static void
395 usb_pc_alloc_mem_cb(void *arg, bus_dma_segment_t *segs,
396     int nseg, int error)
397 {
398 	usb_pc_common_mem_cb(arg, segs, nseg, error, 0);
399 }
400 
401 /*------------------------------------------------------------------------*
402  *	usb_pc_load_mem_cb - BUS-DMA callback function
403  *------------------------------------------------------------------------*/
404 static void
405 usb_pc_load_mem_cb(void *arg, bus_dma_segment_t *segs,
406     int nseg, int error)
407 {
408 	usb_pc_common_mem_cb(arg, segs, nseg, error, 1);
409 }
410 
411 /*------------------------------------------------------------------------*
412  *	usb_pc_common_mem_cb - BUS-DMA callback function
413  *------------------------------------------------------------------------*/
414 static void
415 usb_pc_common_mem_cb(void *arg, bus_dma_segment_t *segs,
416     int nseg, int error, uint8_t isload)
417 {
418 	struct usb_dma_parent_tag *uptag;
419 	struct usb_page_cache *pc;
420 	struct usb_page *pg;
421 	usb_size_t rem;
422 	bus_size_t off;
423 	uint8_t owned;
424 
425 	pc = arg;
426 	uptag = pc->tag_parent;
427 
428 	/*
429 	 * XXX There is sometimes recursive locking here.
430 	 * XXX We should try to find a better solution.
431 	 * XXX Until further the "owned" variable does
432 	 * XXX the trick.
433 	 */
434 
435 	if (error) {
436 		goto done;
437 	}
438 
439 	off = 0;
440 	pg = pc->page_start;
441 	pg->physaddr = segs->ds_addr & ~(USB_PAGE_SIZE - 1);
442 	rem = segs->ds_addr & (USB_PAGE_SIZE - 1);
443 	pc->page_offset_buf = rem;
444 	pc->page_offset_end += rem;
445 #ifdef USB_DEBUG
446 	if (rem != (USB_P2U(pc->buffer) & (USB_PAGE_SIZE - 1))) {
447 		/*
448 		 * This check verifies that the physical address is correct:
449 		 */
450 		DPRINTFN(0, "Page offset was not preserved\n");
451 		error = 1;
452 		goto done;
453 	}
454 #endif
455 	while (1) {
456 		off += USB_PAGE_SIZE;
457 		if (off >= (segs->ds_len + rem)) {
458 			/* page crossing */
459 			nseg--;
460 			segs++;
461 			off = 0;
462 			rem = 0;
463 			if (nseg == 0)
464 				break;
465 		}
466 		pg++;
467 		pg->physaddr = (segs->ds_addr + off) & ~(USB_PAGE_SIZE - 1);
468 	}
469 
470 done:
471 	owned = mtx_owned(uptag->mtx);
472 	if (!owned)
473 		mtx_lock(uptag->mtx);
474 
475 	uptag->dma_error = (error ? 1 : 0);
476 	if (isload) {
477 		(uptag->func) (uptag);
478 	} else {
479 		cv_broadcast(uptag->cv);
480 	}
481 	if (!owned)
482 		mtx_unlock(uptag->mtx);
483 }
484 
485 /*------------------------------------------------------------------------*
486  *	usb_pc_alloc_mem - allocate DMA'able memory
487  *
488  * Returns:
489  *    0: Success
490  * Else: Failure
491  *------------------------------------------------------------------------*/
492 uint8_t
493 usb_pc_alloc_mem(struct usb_page_cache *pc, struct usb_page *pg,
494     usb_size_t size, usb_size_t align)
495 {
496 	struct usb_dma_parent_tag *uptag;
497 	struct usb_dma_tag *utag;
498 	bus_dmamap_t map;
499 	void *ptr;
500 	int err;
501 
502 	uptag = pc->tag_parent;
503 
504 	if (align != 1) {
505 		/*
506 	         * The alignment must be greater or equal to the
507 	         * "size" else the object can be split between two
508 	         * memory pages and we get a problem!
509 	         */
510 		while (align < size) {
511 			align *= 2;
512 			if (align == 0) {
513 				goto error;
514 			}
515 		}
516 #if 1
517 		/*
518 		 * XXX BUS-DMA workaround - FIXME later:
519 		 *
520 		 * We assume that that the aligment at this point of
521 		 * the code is greater than or equal to the size and
522 		 * less than two times the size, so that if we double
523 		 * the size, the size will be greater than the
524 		 * alignment.
525 		 *
526 		 * The bus-dma system has a check for "alignment"
527 		 * being less than "size". If that check fails we end
528 		 * up using contigmalloc which is page based even for
529 		 * small allocations. Try to avoid that to save
530 		 * memory, hence we sometimes to a large number of
531 		 * small allocations!
532 		 */
533 		if (size <= (USB_PAGE_SIZE / 2)) {
534 			size *= 2;
535 		}
536 #endif
537 	}
538 	/* get the correct DMA tag */
539 	utag = usb_dma_tag_find(uptag, size, align);
540 	if (utag == NULL) {
541 		goto error;
542 	}
543 	/* allocate memory */
544 	if (bus_dmamem_alloc(
545 	    utag->tag, &ptr, (BUS_DMA_WAITOK | BUS_DMA_COHERENT), &map)) {
546 		goto error;
547 	}
548 	/* setup page cache */
549 	pc->buffer = ptr;
550 	pc->page_start = pg;
551 	pc->page_offset_buf = 0;
552 	pc->page_offset_end = size;
553 	pc->map = map;
554 	pc->tag = utag->tag;
555 	pc->ismultiseg = (align == 1);
556 
557 	mtx_lock(uptag->mtx);
558 
559 	/* load memory into DMA */
560 	err = bus_dmamap_load(
561 	    utag->tag, map, ptr, size, &usb_pc_alloc_mem_cb,
562 	    pc, (BUS_DMA_WAITOK | BUS_DMA_COHERENT));
563 
564 	if (err == EINPROGRESS) {
565 		cv_wait(uptag->cv, uptag->mtx);
566 		err = 0;
567 	}
568 	mtx_unlock(uptag->mtx);
569 
570 	if (err || uptag->dma_error) {
571 		bus_dmamem_free(utag->tag, ptr, map);
572 		goto error;
573 	}
574 	memset(ptr, 0, size);
575 
576 	usb_pc_cpu_flush(pc);
577 
578 	return (0);
579 
580 error:
581 	/* reset most of the page cache */
582 	pc->buffer = NULL;
583 	pc->page_start = NULL;
584 	pc->page_offset_buf = 0;
585 	pc->page_offset_end = 0;
586 	pc->map = NULL;
587 	pc->tag = NULL;
588 	return (1);
589 }
590 
591 /*------------------------------------------------------------------------*
592  *	usb_pc_free_mem - free DMA memory
593  *
594  * This function is NULL safe.
595  *------------------------------------------------------------------------*/
596 void
597 usb_pc_free_mem(struct usb_page_cache *pc)
598 {
599 	if (pc && pc->buffer) {
600 
601 		bus_dmamap_unload(pc->tag, pc->map);
602 
603 		bus_dmamem_free(pc->tag, pc->buffer, pc->map);
604 
605 		pc->buffer = NULL;
606 	}
607 }
608 
609 /*------------------------------------------------------------------------*
610  *	usb_pc_load_mem - load virtual memory into DMA
611  *
612  * Return values:
613  * 0: Success
614  * Else: Error
615  *------------------------------------------------------------------------*/
616 uint8_t
617 usb_pc_load_mem(struct usb_page_cache *pc, usb_size_t size, uint8_t sync)
618 {
619 	/* setup page cache */
620 	pc->page_offset_buf = 0;
621 	pc->page_offset_end = size;
622 	pc->ismultiseg = 1;
623 
624 	mtx_assert(pc->tag_parent->mtx, MA_OWNED);
625 
626 	if (size > 0) {
627 		if (sync) {
628 			struct usb_dma_parent_tag *uptag;
629 			int err;
630 
631 			uptag = pc->tag_parent;
632 
633 			/*
634 			 * We have to unload the previous loaded DMA
635 			 * pages before trying to load a new one!
636 			 */
637 			bus_dmamap_unload(pc->tag, pc->map);
638 
639 			/*
640 			 * Try to load memory into DMA.
641 			 */
642 			err = bus_dmamap_load(
643 			    pc->tag, pc->map, pc->buffer, size,
644 			    &usb_pc_alloc_mem_cb, pc, BUS_DMA_WAITOK);
645 			if (err == EINPROGRESS) {
646 				cv_wait(uptag->cv, uptag->mtx);
647 				err = 0;
648 			}
649 			if (err || uptag->dma_error) {
650 				return (1);
651 			}
652 		} else {
653 
654 			/*
655 			 * We have to unload the previous loaded DMA
656 			 * pages before trying to load a new one!
657 			 */
658 			bus_dmamap_unload(pc->tag, pc->map);
659 
660 			/*
661 			 * Try to load memory into DMA. The callback
662 			 * will be called in all cases:
663 			 */
664 			if (bus_dmamap_load(
665 			    pc->tag, pc->map, pc->buffer, size,
666 			    &usb_pc_load_mem_cb, pc, BUS_DMA_WAITOK)) {
667 			}
668 		}
669 	} else {
670 		if (!sync) {
671 			/*
672 			 * Call callback so that refcount is decremented
673 			 * properly:
674 			 */
675 			pc->tag_parent->dma_error = 0;
676 			(pc->tag_parent->func) (pc->tag_parent);
677 		}
678 	}
679 	return (0);
680 }
681 
682 /*------------------------------------------------------------------------*
683  *	usb_pc_cpu_invalidate - invalidate CPU cache
684  *------------------------------------------------------------------------*/
685 void
686 usb_pc_cpu_invalidate(struct usb_page_cache *pc)
687 {
688 	if (pc->page_offset_end == pc->page_offset_buf) {
689 		/* nothing has been loaded into this page cache! */
690 		return;
691 	}
692 
693 	/*
694 	 * TODO: We currently do XXX_POSTREAD and XXX_PREREAD at the
695 	 * same time, but in the future we should try to isolate the
696 	 * different cases to optimise the code. --HPS
697 	 */
698 	bus_dmamap_sync(pc->tag, pc->map, BUS_DMASYNC_POSTREAD);
699 	bus_dmamap_sync(pc->tag, pc->map, BUS_DMASYNC_PREREAD);
700 }
701 
702 /*------------------------------------------------------------------------*
703  *	usb_pc_cpu_flush - flush CPU cache
704  *------------------------------------------------------------------------*/
705 void
706 usb_pc_cpu_flush(struct usb_page_cache *pc)
707 {
708 	if (pc->page_offset_end == pc->page_offset_buf) {
709 		/* nothing has been loaded into this page cache! */
710 		return;
711 	}
712 	bus_dmamap_sync(pc->tag, pc->map, BUS_DMASYNC_PREWRITE);
713 }
714 
715 /*------------------------------------------------------------------------*
716  *	usb_pc_dmamap_create - create a DMA map
717  *
718  * Returns:
719  *    0: Success
720  * Else: Failure
721  *------------------------------------------------------------------------*/
722 uint8_t
723 usb_pc_dmamap_create(struct usb_page_cache *pc, usb_size_t size)
724 {
725 	struct usb_xfer_root *info;
726 	struct usb_dma_tag *utag;
727 
728 	/* get info */
729 	info = USB_DMATAG_TO_XROOT(pc->tag_parent);
730 
731 	/* sanity check */
732 	if (info == NULL) {
733 		goto error;
734 	}
735 	utag = usb_dma_tag_find(pc->tag_parent, size, 1);
736 	if (utag == NULL) {
737 		goto error;
738 	}
739 	/* create DMA map */
740 	if (bus_dmamap_create(utag->tag, 0, &pc->map)) {
741 		goto error;
742 	}
743 	pc->tag = utag->tag;
744 	return 0;			/* success */
745 
746 error:
747 	pc->map = NULL;
748 	pc->tag = NULL;
749 	return 1;			/* failure */
750 }
751 
752 /*------------------------------------------------------------------------*
753  *	usb_pc_dmamap_destroy
754  *
755  * This function is NULL safe.
756  *------------------------------------------------------------------------*/
757 void
758 usb_pc_dmamap_destroy(struct usb_page_cache *pc)
759 {
760 	if (pc && pc->tag) {
761 		bus_dmamap_destroy(pc->tag, pc->map);
762 		pc->tag = NULL;
763 		pc->map = NULL;
764 	}
765 }
766 
767 /*------------------------------------------------------------------------*
768  *	usb_dma_tag_find - factored out code
769  *------------------------------------------------------------------------*/
770 struct usb_dma_tag *
771 usb_dma_tag_find(struct usb_dma_parent_tag *udpt,
772     usb_size_t size, usb_size_t align)
773 {
774 	struct usb_dma_tag *udt;
775 	uint8_t nudt;
776 
777 	USB_ASSERT(align > 0, ("Invalid parameter align = 0\n"));
778 	USB_ASSERT(size > 0, ("Invalid parameter size = 0\n"));
779 
780 	udt = udpt->utag_first;
781 	nudt = udpt->utag_max;
782 
783 	while (nudt--) {
784 
785 		if (udt->align == 0) {
786 			usb_dma_tag_create(udt, size, align);
787 			if (udt->tag == NULL) {
788 				return (NULL);
789 			}
790 			udt->align = align;
791 			udt->size = size;
792 			return (udt);
793 		}
794 		if ((udt->align == align) && (udt->size == size)) {
795 			return (udt);
796 		}
797 		udt++;
798 	}
799 	return (NULL);
800 }
801 
802 /*------------------------------------------------------------------------*
803  *	usb_dma_tag_setup - initialise USB DMA tags
804  *------------------------------------------------------------------------*/
805 void
806 usb_dma_tag_setup(struct usb_dma_parent_tag *udpt,
807     struct usb_dma_tag *udt, bus_dma_tag_t dmat,
808     struct mtx *mtx, usb_dma_callback_t *func,
809     uint8_t ndmabits, uint8_t nudt)
810 {
811 	memset(udpt, 0, sizeof(*udpt));
812 
813 	/* sanity checking */
814 	if ((nudt == 0) ||
815 	    (ndmabits == 0) ||
816 	    (mtx == NULL)) {
817 		/* something is corrupt */
818 		return;
819 	}
820 	/* initialise condition variable */
821 	cv_init(udpt->cv, "USB DMA CV");
822 
823 	/* store some information */
824 	udpt->mtx = mtx;
825 	udpt->func = func;
826 	udpt->tag = dmat;
827 	udpt->utag_first = udt;
828 	udpt->utag_max = nudt;
829 	udpt->dma_bits = ndmabits;
830 
831 	while (nudt--) {
832 		memset(udt, 0, sizeof(*udt));
833 		udt->tag_parent = udpt;
834 		udt++;
835 	}
836 }
837 
838 /*------------------------------------------------------------------------*
839  *	usb_bus_tag_unsetup - factored out code
840  *------------------------------------------------------------------------*/
841 void
842 usb_dma_tag_unsetup(struct usb_dma_parent_tag *udpt)
843 {
844 	struct usb_dma_tag *udt;
845 	uint8_t nudt;
846 
847 	udt = udpt->utag_first;
848 	nudt = udpt->utag_max;
849 
850 	while (nudt--) {
851 
852 		if (udt->align) {
853 			/* destroy the USB DMA tag */
854 			usb_dma_tag_destroy(udt);
855 			udt->align = 0;
856 		}
857 		udt++;
858 	}
859 
860 	if (udpt->utag_max) {
861 		/* destroy the condition variable */
862 		cv_destroy(udpt->cv);
863 	}
864 }
865 
866 /*------------------------------------------------------------------------*
867  *	usb_bdma_work_loop
868  *
869  * This function handles loading of virtual buffers into DMA and is
870  * only called when "dma_refcount" is zero.
871  *------------------------------------------------------------------------*/
872 void
873 usb_bdma_work_loop(struct usb_xfer_queue *pq)
874 {
875 	struct usb_xfer_root *info;
876 	struct usb_xfer *xfer;
877 	usb_frcount_t nframes;
878 
879 	xfer = pq->curr;
880 	info = xfer->xroot;
881 
882 	mtx_assert(info->xfer_mtx, MA_OWNED);
883 
884 	if (xfer->error) {
885 		/* some error happened */
886 		USB_BUS_LOCK(info->bus);
887 		usbd_transfer_done(xfer, 0);
888 		USB_BUS_UNLOCK(info->bus);
889 		return;
890 	}
891 	if (!xfer->flags_int.bdma_setup) {
892 		struct usb_page *pg;
893 		usb_frlength_t frlength_0;
894 		uint8_t isread;
895 
896 		xfer->flags_int.bdma_setup = 1;
897 
898 		/* reset BUS-DMA load state */
899 
900 		info->dma_error = 0;
901 
902 		if (xfer->flags_int.isochronous_xfr) {
903 			/* only one frame buffer */
904 			nframes = 1;
905 			frlength_0 = xfer->sumlen;
906 		} else {
907 			/* can be multiple frame buffers */
908 			nframes = xfer->nframes;
909 			frlength_0 = xfer->frlengths[0];
910 		}
911 
912 		/*
913 		 * Set DMA direction first. This is needed to
914 		 * select the correct cache invalidate and cache
915 		 * flush operations.
916 		 */
917 		isread = USB_GET_DATA_ISREAD(xfer);
918 		pg = xfer->dma_page_ptr;
919 
920 		if (xfer->flags_int.control_xfr &&
921 		    xfer->flags_int.control_hdr) {
922 			/* special case */
923 			if (xfer->flags_int.usb_mode == USB_MODE_DEVICE) {
924 				/* The device controller writes to memory */
925 				xfer->frbuffers[0].isread = 1;
926 			} else {
927 				/* The host controller reads from memory */
928 				xfer->frbuffers[0].isread = 0;
929 			}
930 		} else {
931 			/* default case */
932 			xfer->frbuffers[0].isread = isread;
933 		}
934 
935 		/*
936 		 * Setup the "page_start" pointer which points to an array of
937 		 * USB pages where information about the physical address of a
938 		 * page will be stored. Also initialise the "isread" field of
939 		 * the USB page caches.
940 		 */
941 		xfer->frbuffers[0].page_start = pg;
942 
943 		info->dma_nframes = nframes;
944 		info->dma_currframe = 0;
945 		info->dma_frlength_0 = frlength_0;
946 
947 		pg += (frlength_0 / USB_PAGE_SIZE);
948 		pg += 2;
949 
950 		while (--nframes > 0) {
951 			xfer->frbuffers[nframes].isread = isread;
952 			xfer->frbuffers[nframes].page_start = pg;
953 
954 			pg += (xfer->frlengths[nframes] / USB_PAGE_SIZE);
955 			pg += 2;
956 		}
957 
958 	}
959 	if (info->dma_error) {
960 		USB_BUS_LOCK(info->bus);
961 		usbd_transfer_done(xfer, USB_ERR_DMA_LOAD_FAILED);
962 		USB_BUS_UNLOCK(info->bus);
963 		return;
964 	}
965 	if (info->dma_currframe != info->dma_nframes) {
966 
967 		if (info->dma_currframe == 0) {
968 			/* special case */
969 			usb_pc_load_mem(xfer->frbuffers,
970 			    info->dma_frlength_0, 0);
971 		} else {
972 			/* default case */
973 			nframes = info->dma_currframe;
974 			usb_pc_load_mem(xfer->frbuffers + nframes,
975 			    xfer->frlengths[nframes], 0);
976 		}
977 
978 		/* advance frame index */
979 		info->dma_currframe++;
980 
981 		return;
982 	}
983 	/* go ahead */
984 	usb_bdma_pre_sync(xfer);
985 
986 	/* start loading next USB transfer, if any */
987 	usb_command_wrapper(pq, NULL);
988 
989 	/* finally start the hardware */
990 	usbd_pipe_enter(xfer);
991 }
992 
993 /*------------------------------------------------------------------------*
994  *	usb_bdma_done_event
995  *
996  * This function is called when the BUS-DMA has loaded virtual memory
997  * into DMA, if any.
998  *------------------------------------------------------------------------*/
999 void
1000 usb_bdma_done_event(struct usb_dma_parent_tag *udpt)
1001 {
1002 	struct usb_xfer_root *info;
1003 
1004 	info = USB_DMATAG_TO_XROOT(udpt);
1005 
1006 	mtx_assert(info->xfer_mtx, MA_OWNED);
1007 
1008 	/* copy error */
1009 	info->dma_error = udpt->dma_error;
1010 
1011 	/* enter workloop again */
1012 	usb_command_wrapper(&info->dma_q,
1013 	    info->dma_q.curr);
1014 }
1015 
1016 /*------------------------------------------------------------------------*
1017  *	usb_bdma_pre_sync
1018  *
1019  * This function handles DMA synchronisation that must be done before
1020  * an USB transfer is started.
1021  *------------------------------------------------------------------------*/
1022 void
1023 usb_bdma_pre_sync(struct usb_xfer *xfer)
1024 {
1025 	struct usb_page_cache *pc;
1026 	usb_frcount_t nframes;
1027 
1028 	if (xfer->flags_int.isochronous_xfr) {
1029 		/* only one frame buffer */
1030 		nframes = 1;
1031 	} else {
1032 		/* can be multiple frame buffers */
1033 		nframes = xfer->nframes;
1034 	}
1035 
1036 	pc = xfer->frbuffers;
1037 
1038 	while (nframes--) {
1039 
1040 		if (pc->isread) {
1041 			usb_pc_cpu_invalidate(pc);
1042 		} else {
1043 			usb_pc_cpu_flush(pc);
1044 		}
1045 		pc++;
1046 	}
1047 }
1048 
1049 /*------------------------------------------------------------------------*
1050  *	usb_bdma_post_sync
1051  *
1052  * This function handles DMA synchronisation that must be done after
1053  * an USB transfer is complete.
1054  *------------------------------------------------------------------------*/
1055 void
1056 usb_bdma_post_sync(struct usb_xfer *xfer)
1057 {
1058 	struct usb_page_cache *pc;
1059 	usb_frcount_t nframes;
1060 
1061 	if (xfer->flags_int.isochronous_xfr) {
1062 		/* only one frame buffer */
1063 		nframes = 1;
1064 	} else {
1065 		/* can be multiple frame buffers */
1066 		nframes = xfer->nframes;
1067 	}
1068 
1069 	pc = xfer->frbuffers;
1070 
1071 	while (nframes--) {
1072 		if (pc->isread) {
1073 			usb_pc_cpu_invalidate(pc);
1074 		}
1075 		pc++;
1076 	}
1077 }
1078 
1079 #endif
1080