busdma_machdep.c revision 170978 
1/*-
2 * Copyright (c) 2002 Peter Grehan
3 * Copyright (c) 1997, 1998 Justin T. Gibbs.
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions, and the following disclaimer,
11 *    without modification, immediately at the beginning of the file.
12 * 2. The name of the author may not be used to endorse or promote products
13 *    derived from this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
19 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 *   From i386/busdma_machdep.c,v 1.26 2002/04/19 22:58:09 alfred
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: head/sys/powerpc/powerpc/busdma_machdep.c 170978 2007-06-22 03:54:53Z yongari $");
32
33/*
34 * MacPPC bus dma support routines
35 */
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/malloc.h>
40#include <sys/bus.h>
41#include <sys/interrupt.h>
42#include <sys/lock.h>
43#include <sys/proc.h>
44#include <sys/mutex.h>
45#include <sys/mbuf.h>
46#include <sys/uio.h>
47
48#include <vm/vm.h>
49#include <vm/vm_page.h>
50#include <vm/vm_map.h>
51
52#include <machine/atomic.h>
53#include <machine/bus.h>
54#include <machine/cpufunc.h>
55
56struct bus_dma_tag {
57	bus_dma_tag_t     parent;
58	bus_size_t        alignment;
59	bus_size_t        boundary;
60	bus_addr_t        lowaddr;
61	bus_addr_t        highaddr;
62	bus_dma_filter_t *filter;
63	void             *filterarg;
64	bus_size_t        maxsize;
65	u_int             nsegments;
66	bus_size_t        maxsegsz;
67	int               flags;
68	int               ref_count;
69	int               map_count;
70	bus_dma_lock_t	 *lockfunc;
71	void		 *lockfuncarg;
72};
73
74struct bus_dmamap {
75        bus_dma_tag_t          dmat;
76        void                  *buf;             /* unmapped buffer pointer */
77        bus_size_t             buflen;          /* unmapped buffer length */
78        bus_dmamap_callback_t *callback;
79        void                  *callback_arg;
80};
81
82/*
83 * Convenience function for manipulating driver locks from busdma (during
84 * busdma_swi, for example).  Drivers that don't provide their own locks
85 * should specify &Giant to dmat->lockfuncarg.  Drivers that use their own
86 * non-mutex locking scheme don't have to use this at all.
87 */
88void
89busdma_lock_mutex(void *arg, bus_dma_lock_op_t op)
90{
91	struct mtx *dmtx;
92
93	dmtx = (struct mtx *)arg;
94	switch (op) {
95	case BUS_DMA_LOCK:
96		mtx_lock(dmtx);
97		break;
98	case BUS_DMA_UNLOCK:
99		mtx_unlock(dmtx);
100		break;
101	default:
102		panic("Unknown operation 0x%x for busdma_lock_mutex!", op);
103	}
104}
105
106/*
107 * dflt_lock should never get called.  It gets put into the dma tag when
108 * lockfunc == NULL, which is only valid if the maps that are associated
109 * with the tag are meant to never be defered.
110 * XXX Should have a way to identify which driver is responsible here.
111 */
112static void
113dflt_lock(void *arg, bus_dma_lock_op_t op)
114{
115#ifdef INVARIANTS
116	panic("driver error: busdma dflt_lock called");
117#else
118	printf("DRIVER_ERROR: busdma dflt_lock called\n");
119#endif
120}
121
122/*
123 * Allocate a device specific dma_tag.
124 */
125int
126bus_dma_tag_create(bus_dma_tag_t parent, bus_size_t alignment,
127		   bus_size_t boundary, bus_addr_t lowaddr,
128		   bus_addr_t highaddr, bus_dma_filter_t *filter,
129		   void *filterarg, bus_size_t maxsize, int nsegments,
130		   bus_size_t maxsegsz, int flags, bus_dma_lock_t *lockfunc,
131		   void *lockfuncarg, bus_dma_tag_t *dmat)
132{
133	bus_dma_tag_t newtag;
134	int error = 0;
135
136	/* Return a NULL tag on failure */
137	*dmat = NULL;
138
139	newtag = (bus_dma_tag_t)malloc(sizeof(*newtag), M_DEVBUF, M_NOWAIT);
140	if (newtag == NULL)
141		return (ENOMEM);
142
143	newtag->parent = parent;
144	newtag->alignment = alignment;
145	newtag->boundary = boundary;
146	newtag->lowaddr = trunc_page((vm_offset_t)lowaddr) + (PAGE_SIZE - 1);
147	newtag->highaddr = trunc_page((vm_offset_t)highaddr) + (PAGE_SIZE - 1);
148	newtag->filter = filter;
149	newtag->filterarg = filterarg;
150        newtag->maxsize = maxsize;
151        newtag->nsegments = nsegments;
152	newtag->maxsegsz = maxsegsz;
153	newtag->flags = flags;
154	newtag->ref_count = 1; /* Count ourself */
155	newtag->map_count = 0;
156	if (lockfunc != NULL) {
157		newtag->lockfunc = lockfunc;
158		newtag->lockfuncarg = lockfuncarg;
159	} else {
160		newtag->lockfunc = dflt_lock;
161		newtag->lockfuncarg = NULL;
162	}
163
164        /*
165	 * Take into account any restrictions imposed by our parent tag
166	 */
167        if (parent != NULL) {
168                newtag->lowaddr = min(parent->lowaddr, newtag->lowaddr);
169                newtag->highaddr = max(parent->highaddr, newtag->highaddr);
170		if (newtag->boundary == 0)
171			newtag->boundary = parent->boundary;
172		else if (parent->boundary != 0)
173                	newtag->boundary = MIN(parent->boundary,
174					       newtag->boundary);
175                if (newtag->filter == NULL) {
176                        /*
177                         * Short circuit looking at our parent directly
178                         * since we have encapsulated all of its information
179                         */
180                        newtag->filter = parent->filter;
181                        newtag->filterarg = parent->filterarg;
182                        newtag->parent = parent->parent;
183		}
184		if (newtag->parent != NULL)
185			atomic_add_int(&parent->ref_count, 1);
186	}
187
188	*dmat = newtag;
189	return (error);
190}
191
192int
193bus_dma_tag_destroy(bus_dma_tag_t dmat)
194{
195	if (dmat != NULL) {
196
197                if (dmat->map_count != 0)
198                        return (EBUSY);
199
200                while (dmat != NULL) {
201                        bus_dma_tag_t parent;
202
203                        parent = dmat->parent;
204                        atomic_subtract_int(&dmat->ref_count, 1);
205                        if (dmat->ref_count == 0) {
206                                free(dmat, M_DEVBUF);
207                                /*
208                                 * Last reference count, so
209                                 * release our reference
210                                 * count on our parent.
211                                 */
212                                dmat = parent;
213                        } else
214                                dmat = NULL;
215                }
216        }
217        return (0);
218}
219
220/*
221 * Allocate a handle for mapping from kva/uva/physical
222 * address space into bus device space.
223 */
224int
225bus_dmamap_create(bus_dma_tag_t dmat, int flags, bus_dmamap_t *mapp)
226{
227	*mapp = NULL;
228	dmat->map_count++;
229
230	return (0);
231}
232
233/*
234 * Destroy a handle for mapping from kva/uva/physical
235 * address space into bus device space.
236 */
237int
238bus_dmamap_destroy(bus_dma_tag_t dmat, bus_dmamap_t map)
239{
240        if (map != NULL) {
241		panic("dmamap_destroy: NULL?\n");
242        }
243        dmat->map_count--;
244        return (0);
245}
246
247/*
248 * Allocate a piece of memory that can be efficiently mapped into
249 * bus device space based on the constraints lited in the dma tag.
250 * A dmamap to for use with dmamap_load is also allocated.
251 */
252int
253bus_dmamem_alloc(bus_dma_tag_t dmat, void** vaddr, int flags,
254                 bus_dmamap_t *mapp)
255{
256	int mflags;
257
258	if (flags & BUS_DMA_NOWAIT)
259		mflags = M_NOWAIT;
260	else
261		mflags = M_WAITOK;
262	if (flags & BUS_DMA_ZERO)
263		mflags |= M_ZERO;
264
265        *mapp = NULL;
266
267	/*
268	 * XXX:
269	 * (dmat->alignment < dmat->maxsize) is just a quick hack; the exact
270	 * alignment guarantees of malloc need to be nailed down, and the
271	 * code below should be rewritten to take that into account.
272	 *
273	 * In the meantime, we'll return an error if malloc gets it wrong.
274	 */
275	if (dmat->maxsize <= PAGE_SIZE &&
276	    dmat->alignment < dmat->maxsize) {
277		*vaddr = malloc(dmat->maxsize, M_DEVBUF, mflags);
278        } else {
279                /*
280                 * XXX Use Contigmalloc until it is merged into this facility
281                 *     and handles multi-seg allocations.  Nobody is doing
282                 *     multi-seg allocations yet though.
283                 */
284                *vaddr = contigmalloc(dmat->maxsize, M_DEVBUF, mflags,
285                    0ul, dmat->lowaddr, dmat->alignment? dmat->alignment : 1ul,
286                    dmat->boundary);
287        }
288
289        if (*vaddr == NULL)
290                return (ENOMEM);
291
292	if ((uintptr_t)*vaddr % dmat->alignment)
293		printf("XXX: %s: alignment not respected!\n", __func__);
294
295        return (0);
296}
297
298/*
299 * Free a piece of memory and it's allocated dmamap, that was allocated
300 * via bus_dmamem_alloc.  Make the same choice for free/contigfree.
301 */
302void
303bus_dmamem_free(bus_dma_tag_t dmat, void *vaddr, bus_dmamap_t map)
304{
305        if (map != NULL)
306                panic("bus_dmamem_free: Invalid map freed\n");
307        if (dmat->maxsize <= PAGE_SIZE &&
308	    dmat->alignment < dmat->maxsize)
309		free(vaddr, M_DEVBUF);
310        else
311		contigfree(vaddr, dmat->maxsize, M_DEVBUF);
312}
313
314/*
315 * Map the buffer buf into bus space using the dmamap map.
316 */
317int
318bus_dmamap_load(bus_dma_tag_t dmat, bus_dmamap_t map, void *buf,
319                bus_size_t buflen, bus_dmamap_callback_t *callback,
320                void *callback_arg, int flags)
321{
322        vm_offset_t             vaddr;
323        vm_offset_t             paddr;
324#ifdef __CC_SUPPORTS_DYNAMIC_ARRAY_INIT
325        bus_dma_segment_t       dm_segments[dmat->nsegments];
326#else
327        bus_dma_segment_t       dm_segments[BUS_DMAMAP_NSEGS];
328#endif
329        bus_dma_segment_t      *sg;
330        int                     seg;
331        int                     error = 0;
332        vm_offset_t             nextpaddr;
333
334        if (map != NULL)
335		panic("bus_dmamap_load: Invalid map\n");
336
337        vaddr = (vm_offset_t)buf;
338        sg = &dm_segments[0];
339        seg = 1;
340        sg->ds_len = 0;
341        nextpaddr = 0;
342
343        do {
344		bus_size_t      size;
345
346                paddr = pmap_kextract(vaddr);
347                size = PAGE_SIZE - (paddr & PAGE_MASK);
348                if (size > buflen)
349                        size = buflen;
350
351                if (sg->ds_len == 0) {
352                        sg->ds_addr = paddr;
353                        sg->ds_len = size;
354                } else if (paddr == nextpaddr) {
355                        sg->ds_len += size;
356                } else {
357                        /* Go to the next segment */
358                        sg++;
359                        seg++;
360                        if (seg > dmat->nsegments)
361				break;
362                        sg->ds_addr = paddr;
363                        sg->ds_len = size;
364                }
365                vaddr += size;
366                nextpaddr = paddr + size;
367                buflen -= size;
368
369	} while (buflen > 0);
370
371	if (buflen != 0) {
372		printf("bus_dmamap_load: Too many segs! buf_len = 0x%lx\n",
373		    (u_long)buflen);
374		error = EFBIG;
375	}
376
377	(*callback)(callback_arg, dm_segments, seg, error);
378
379	return (0);
380}
381
382/*
383 * Utility function to load a linear buffer.  lastaddrp holds state
384 * between invocations (for multiple-buffer loads).  segp contains
385 * the starting segment on entrance, and the ending segment on exit.
386 * first indicates if this is the first invocation of this function.
387 */
388static int
389bus_dmamap_load_buffer(bus_dma_tag_t dmat, bus_dma_segment_t segs[],
390    void *buf, bus_size_t buflen, struct thread *td,
391    int flags, vm_offset_t *lastaddrp, int *segp,
392    int first)
393{
394	bus_size_t sgsize;
395	bus_addr_t curaddr, lastaddr, baddr, bmask;
396	vm_offset_t vaddr = (vm_offset_t)buf;
397	int seg;
398	pmap_t pmap;
399
400	if (td != NULL)
401		pmap = vmspace_pmap(td->td_proc->p_vmspace);
402	else
403		pmap = NULL;
404
405	lastaddr = *lastaddrp;
406	bmask = ~(dmat->boundary - 1);
407
408	for (seg = *segp; buflen > 0 ; ) {
409		/*
410		 * Get the physical address for this segment.
411		 */
412		if (pmap)
413			curaddr = pmap_extract(pmap, vaddr);
414		else
415			curaddr = pmap_kextract(vaddr);
416
417		/*
418		 * Compute the segment size, and adjust counts.
419		 */
420		sgsize = PAGE_SIZE - ((u_long)curaddr & PAGE_MASK);
421		if (sgsize > dmat->maxsegsz)
422			sgsize = dmat->maxsegsz;
423		if (buflen < sgsize)
424			sgsize = buflen;
425
426		/*
427		 * Make sure we don't cross any boundaries.
428		 */
429		if (dmat->boundary > 0) {
430			baddr = (curaddr + dmat->boundary) & bmask;
431			if (sgsize > (baddr - curaddr))
432				sgsize = (baddr - curaddr);
433		}
434
435		/*
436		 * Insert chunk into a segment, coalescing with
437		 * the previous segment if possible.
438		 */
439		if (first) {
440			segs[seg].ds_addr = curaddr;
441			segs[seg].ds_len = sgsize;
442			first = 0;
443		} else {
444			if (curaddr == lastaddr &&
445			    (segs[seg].ds_len + sgsize) <= dmat->maxsegsz &&
446			    (dmat->boundary == 0 ||
447			     (segs[seg].ds_addr & bmask) == (curaddr & bmask)))
448				segs[seg].ds_len += sgsize;
449			else {
450				if (++seg >= dmat->nsegments)
451					break;
452				segs[seg].ds_addr = curaddr;
453				segs[seg].ds_len = sgsize;
454			}
455		}
456
457		lastaddr = curaddr + sgsize;
458		vaddr += sgsize;
459		buflen -= sgsize;
460	}
461
462	*segp = seg;
463	*lastaddrp = lastaddr;
464
465	/*
466	 * Did we fit?
467	 */
468	return (buflen != 0 ? EFBIG : 0); /* XXX better return value here? */
469}
470
471/*
472 * Like bus_dmamap_load(), but for mbufs.
473 */
474int
475bus_dmamap_load_mbuf(bus_dma_tag_t dmat, bus_dmamap_t map, struct mbuf *m0,
476		     bus_dmamap_callback2_t *callback, void *callback_arg,
477		     int flags)
478{
479#ifdef __CC_SUPPORTS_DYNAMIC_ARRAY_INIT
480	bus_dma_segment_t dm_segments[dmat->nsegments];
481#else
482	bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
483#endif
484	int nsegs = 0, error = 0;
485
486	M_ASSERTPKTHDR(m0);
487
488	if (m0->m_pkthdr.len <= dmat->maxsize) {
489		int first = 1;
490		vm_offset_t lastaddr = 0;
491		struct mbuf *m;
492
493		for (m = m0; m != NULL && error == 0; m = m->m_next) {
494			if (m->m_len > 0) {
495				error = bus_dmamap_load_buffer(dmat,
496				    dm_segments, m->m_data, m->m_len, NULL,
497				    flags, &lastaddr, &nsegs, first);
498				first = 0;
499			}
500		}
501	} else {
502		error = EINVAL;
503	}
504
505	if (error) {
506		/*
507		 * force "no valid mappings" on error in callback.
508		 */
509		(*callback)(callback_arg, dm_segments, 0, 0, error);
510	} else {
511		(*callback)(callback_arg, dm_segments, nsegs+1,
512		    m0->m_pkthdr.len, error);
513	}
514	return (error);
515}
516
517int
518bus_dmamap_load_mbuf_sg(bus_dma_tag_t dmat, bus_dmamap_t map, struct mbuf *m0,
519			bus_dma_segment_t *segs, int *nsegs, int flags)
520{
521	int error = 0;
522
523	M_ASSERTPKTHDR(m0);
524
525	*nsegs = 0;
526
527	if (m0->m_pkthdr.len <= dmat->maxsize) {
528		int first = 1;
529		vm_offset_t lastaddr = 0;
530		struct mbuf *m;
531
532		for (m = m0; m != NULL && error == 0; m = m->m_next) {
533			if (m->m_len > 0) {
534				error = bus_dmamap_load_buffer(dmat,
535				    segs, m->m_data, m->m_len, NULL,
536				    flags, &lastaddr, nsegs, first);
537				first = 0;
538			}
539		}
540		++*nsegs;
541	} else {
542		error = EINVAL;
543	}
544
545	return (error);
546}
547
548/*
549 * Like bus_dmamap_load(), but for uios.
550 */
551int
552bus_dmamap_load_uio(bus_dma_tag_t dmat, bus_dmamap_t map, struct uio *uio,
553    bus_dmamap_callback2_t *callback, void *callback_arg,
554    int flags)
555{
556	vm_offset_t lastaddr;
557#ifdef __CC_SUPPORTS_DYNAMIC_ARRAY_INIT
558	bus_dma_segment_t dm_segments[dmat->nsegments];
559#else
560	bus_dma_segment_t dm_segments[BUS_DMAMAP_NSEGS];
561#endif
562	int nsegs, i, error, first;
563	bus_size_t resid;
564	struct iovec *iov;
565	struct thread *td = NULL;
566
567	resid = uio->uio_resid;
568	iov = uio->uio_iov;
569
570	if (uio->uio_segflg == UIO_USERSPACE) {
571		td = uio->uio_td;
572		KASSERT(td != NULL,
573		    ("bus_dmamap_load_uio: USERSPACE but no proc"));
574	}
575
576	first = 1;
577	nsegs = error = 0;
578	for (i = 0; i < uio->uio_iovcnt && resid != 0 && !error; i++) {
579		/*
580		 * Now at the first iovec to load.  Load each iovec
581		 * until we have exhausted the residual count.
582		 */
583		bus_size_t minlen =
584		    resid < iov[i].iov_len ? resid : iov[i].iov_len;
585		caddr_t addr = (caddr_t) iov[i].iov_base;
586
587		if (minlen > 0) {
588			error = bus_dmamap_load_buffer(dmat, dm_segments, addr,
589			    minlen, td, flags, &lastaddr, &nsegs, first);
590
591			first = 0;
592
593			resid -= minlen;
594		}
595	}
596
597	if (error) {
598		/*
599		 * force "no valid mappings" on error in callback.
600		 */
601		(*callback)(callback_arg, dm_segments, 0, 0, error);
602	} else {
603		(*callback)(callback_arg, dm_segments, nsegs+1,
604		    uio->uio_resid, error);
605	}
606
607	return (error);
608}
609
610/*
611 * Release the mapping held by map. A no-op on PowerPC.
612 */
613void
614_bus_dmamap_unload(bus_dma_tag_t dmat, bus_dmamap_t map)
615{
616
617	return;
618}
619
620void
621_bus_dmamap_sync(bus_dma_tag_t dmat, bus_dmamap_t map, bus_dmasync_op_t op)
622{
623
624	return;
625}
626