xref: /netbsd-src/sys/rump/dev/lib/libpci/rumpdev_bus_dma.c (revision 53d1339bf7f9c7367b35a9e1ebe693f9b047a47b)
1 /*	$NetBSD: rumpdev_bus_dma.c,v 1.10 2020/11/02 18:58:06 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 Antti Kantee
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*-
30  * Copyright (c) 1996, 1997, 1998 The NetBSD Foundation, Inc.
31  * All rights reserved.
32  *
33  * This code is derived from software contributed to The NetBSD Foundation
34  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
35  * NASA Ames Research Center.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  *
46  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
47  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
48  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
49  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
50  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
51  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
52  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
53  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
54  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
55  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
56  * POSSIBILITY OF SUCH DAMAGE.
57  */
58 
59 /*
60  * bus_dma(9) implementation which runs on top of rump kernel hypercalls.
61  * It's essentially the same as the PowerPC implementation its based on,
62  * except with some indirection and PowerPC MD features removed.
63  * This should/could be expected to run on x86, other archs may need
64  * some cache flushing hooks.
65  *
66  * From sys/arch/powerpc/powerpc/bus_dma.c:
67  *	NetBSD: bus_dma.c,v 1.46 2012/02/01 09:54:03 matt Exp
68  */
69 
70 #include <sys/cdefs.h>
71 __KERNEL_RCSID(0, "$NetBSD: rumpdev_bus_dma.c,v 1.10 2020/11/02 18:58:06 christos Exp $");
72 
73 #include <sys/param.h>
74 #include <sys/systm.h>
75 #include <sys/kernel.h>
76 #include <sys/device.h>
77 #include <sys/kmem.h>
78 #include <sys/proc.h>
79 #include <sys/mbuf.h>
80 #include <sys/bus.h>
81 #include <sys/intr.h>
82 
83 #include "pci_user.h"
84 
85 #define	EIEIO	membar_sync()
86 
87 int	_bus_dmamap_load_buffer (bus_dma_tag_t, bus_dmamap_t, void *,
88 	    bus_size_t, struct vmspace *, int, paddr_t *, int *, int);
89 
90 /*
91  * Common function for DMA map creation.  May be called by bus-specific
92  * DMA map creation functions.
93  */
94 int
95 bus_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments,
96 	bus_size_t maxsegsz, bus_size_t boundary, int flags,
97 	bus_dmamap_t *dmamp)
98 {
99 	bus_dmamap_t map;
100 	void *mapstore;
101 	size_t mapsize;
102 
103 	/*
104 	 * Allocate and initialize the DMA map.  The end of the map
105 	 * is a variable-sized array of segments, so we allocate enough
106 	 * room for them in one shot.
107 	 *
108 	 * Note we don't preserve the WAITOK or NOWAIT flags.  Preservation
109 	 * of ALLOCNOW notifies others that we've reserved these resources,
110 	 * and they are not to be freed.
111 	 *
112 	 * The bus_dmamap_t includes one bus_dma_segment_t, hence
113 	 * the (nsegments - 1).
114 	 */
115 	mapsize = sizeof(*map) + sizeof(bus_dma_segment_t [nsegments - 1]);
116 	if ((mapstore = kmem_intr_alloc(mapsize,
117 	    (flags & BUS_DMA_NOWAIT) ? KM_NOSLEEP : KM_SLEEP)) == NULL)
118 		return (ENOMEM);
119 
120 	memset(mapstore, 0, mapsize);
121 	map = (void *)mapstore;
122 	map->_dm_size = size;
123 	map->_dm_segcnt = nsegments;
124 	map->_dm_maxmaxsegsz = maxsegsz;
125 	map->_dm_boundary = boundary;
126 	map->_dm_bounce_thresh = 0;
127 	map->_dm_flags = flags & ~(BUS_DMA_WAITOK|BUS_DMA_NOWAIT);
128 	map->dm_maxsegsz = maxsegsz;
129 	map->dm_mapsize = 0;		/* no valid mappings */
130 	map->dm_nsegs = 0;
131 
132 	*dmamp = map;
133 	return (0);
134 }
135 
136 /*
137  * Common function for DMA map destruction.  May be called by bus-specific
138  * DMA map destruction functions.
139  */
140 void
141 bus_dmamap_destroy(bus_dma_tag_t t, bus_dmamap_t map)
142 {
143 
144 	size_t mapsize = sizeof(*map)
145 	    + sizeof(bus_dma_segment_t [map->_dm_segcnt - 1]);
146 	kmem_intr_free(map, mapsize);
147 }
148 
149 /*
150  * Utility function to load a linear buffer.  lastaddrp holds state
151  * between invocations (for multiple-buffer loads).  segp contains
152  * the starting segment on entrance, and the ending segment on exit.
153  * first indicates if this is the first invocation of this function.
154  */
155 int
156 _bus_dmamap_load_buffer(bus_dma_tag_t t, bus_dmamap_t map,
157 	void *buf, bus_size_t buflen, struct vmspace *vm, int flags,
158 	paddr_t *lastaddrp, int *segp, int first)
159 {
160 	bus_size_t sgsize;
161 	bus_addr_t curaddr, lastaddr, baddr, bmask;
162 	vaddr_t vaddr = (vaddr_t)buf;
163 	int seg;
164 
165 //	printf("%s(%p,%p,%p,%u,%p,%#x,%p,%p,%u)\n", __func__,
166 //	    t, map, buf, buflen, vm, flags, lastaddrp, segp, first);
167 
168 	lastaddr = *lastaddrp;
169 	bmask = ~(map->_dm_boundary - 1);
170 
171 	for (seg = *segp; buflen > 0 ; ) {
172 		/*
173 		 * Get the physical address for this segment.
174 		 */
175 		if (!VMSPACE_IS_KERNEL_P(vm))
176 			(void) pmap_extract(vm_map_pmap(&vm->vm_map),
177 			    vaddr, (void *)&curaddr);
178 		else
179 			curaddr = vtophys(vaddr);
180 
181 		/*
182 		 * If we're beyond the bounce threshold, notify
183 		 * the caller.
184 		 */
185 		if (map->_dm_bounce_thresh != 0 &&
186 		    curaddr >= map->_dm_bounce_thresh)
187 			return (EINVAL);
188 
189 		/*
190 		 * Compute the segment size, and adjust counts.
191 		 */
192 		sgsize = PAGE_SIZE - ((u_long)vaddr & PGOFSET);
193 		if (buflen < sgsize)
194 			sgsize = buflen;
195 		sgsize = MIN(sgsize, map->dm_maxsegsz);
196 
197 		/*
198 		 * Make sure we don't cross any boundaries.
199 		 */
200 		if (map->_dm_boundary > 0) {
201 			baddr = (curaddr + map->_dm_boundary) & bmask;
202 			if (sgsize > (baddr - curaddr))
203 				sgsize = (baddr - curaddr);
204 		}
205 
206 		/*
207 		 * Insert chunk into a segment, coalescing with
208 		 * the previous segment if possible.
209 		 */
210 		if (first) {
211 			map->dm_segs[seg].ds_addr
212 			    = rumpcomp_pci_virt_to_mach((void *)curaddr);
213 			map->dm_segs[seg].ds_len = sgsize;
214 			first = 0;
215 		} else {
216 			if (curaddr == lastaddr &&
217 			    (map->dm_segs[seg].ds_len + sgsize) <=
218 			     map->dm_maxsegsz &&
219 			    (map->_dm_boundary == 0 ||
220 			     (map->dm_segs[seg].ds_addr & bmask) ==
221 			     (rumpcomp_pci_virt_to_mach((void*)curaddr)&bmask)))
222 				map->dm_segs[seg].ds_len += sgsize;
223 			else {
224 				if (++seg >= map->_dm_segcnt)
225 					break;
226 				map->dm_segs[seg].ds_addr =
227 				    rumpcomp_pci_virt_to_mach((void *)curaddr);
228 				map->dm_segs[seg].ds_len = sgsize;
229 			}
230 		}
231 
232 		lastaddr = curaddr + sgsize;
233 		vaddr += sgsize;
234 		buflen -= sgsize;
235 	}
236 
237 	*segp = seg;
238 	*lastaddrp = lastaddr;
239 
240 	/*
241 	 * Did we fit?
242 	 */
243 	if (buflen != 0)
244 		return (EFBIG);		/* XXX better return value here? */
245 
246 	return (0);
247 }
248 
249 /*
250  * Common function for loading a DMA map with a linear buffer.  May
251  * be called by bus-specific DMA map load functions.
252  */
253 int
254 bus_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map,
255 	void *buf, bus_size_t buflen, struct proc *p, int flags)
256 {
257 	paddr_t lastaddr = 0;
258 	int seg, error;
259 	struct vmspace *vm;
260 
261 	/*
262 	 * Make sure that on error condition we return "no valid mappings".
263 	 */
264 	map->dm_mapsize = 0;
265 	map->dm_nsegs = 0;
266 	KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
267 
268 	if (buflen > map->_dm_size)
269 		return (EINVAL);
270 
271 	if (p != NULL) {
272 		vm = p->p_vmspace;
273 	} else {
274 		vm = vmspace_kernel();
275 	}
276 
277 	seg = 0;
278 	error = _bus_dmamap_load_buffer(t, map, buf, buflen, vm, flags,
279 		&lastaddr, &seg, 1);
280 	if (error == 0) {
281 		map->dm_mapsize = buflen;
282 		map->dm_nsegs = seg + 1;
283 	}
284 	return (error);
285 }
286 
287 /*
288  * Like _bus_dmamap_load(), but for mbufs.
289  */
290 int
291 bus_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map,
292 	struct mbuf *m0, int flags)
293 {
294 	paddr_t lastaddr = 0;
295 	int seg, error, first;
296 	struct mbuf *m;
297 
298 	/*
299 	 * Make sure that on error condition we return "no valid mappings."
300 	 */
301 	map->dm_mapsize = 0;
302 	map->dm_nsegs = 0;
303 	KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
304 
305 #ifdef DIAGNOSTIC
306 	if ((m0->m_flags & M_PKTHDR) == 0)
307 		panic("_bus_dmamap_load_mbuf: no packet header");
308 #endif
309 
310 	if (m0->m_pkthdr.len > map->_dm_size)
311 		return (EINVAL);
312 
313 	first = 1;
314 	seg = 0;
315 	error = 0;
316 	for (m = m0; m != NULL && error == 0; m = m->m_next, first = 0) {
317 		if (m->m_len == 0)
318 			continue;
319 #ifdef POOL_VTOPHYS
320 		/* XXX Could be better about coalescing. */
321 		/* XXX Doesn't check boundaries. */
322 		switch (m->m_flags & (M_EXT|M_EXT_CLUSTER)) {
323 		case M_EXT|M_EXT_CLUSTER:
324 			/* XXX KDASSERT */
325 			KASSERT(m->m_ext.ext_paddr != M_PADDR_INVALID);
326 			lastaddr = m->m_ext.ext_paddr +
327 			    (m->m_data - m->m_ext.ext_buf);
328  have_addr:
329 			if (first == 0 && ++seg >= map->_dm_segcnt) {
330 				error = EFBIG;
331 				continue;
332 			}
333 			map->dm_segs[seg].ds_addr =
334 			    rumpcomp_pci_virt_to_mach((void *)lastaddr);
335 			map->dm_segs[seg].ds_len = m->m_len;
336 			lastaddr += m->m_len;
337 			continue;
338 
339 		case 0:
340 			lastaddr = m->m_paddr + M_BUFOFFSET(m) +
341 			    (m->m_data - M_BUFADDR(m));
342 			goto have_addr;
343 
344 		default:
345 			break;
346 		}
347 #endif
348 		error = _bus_dmamap_load_buffer(t, map, m->m_data,
349 		    m->m_len, vmspace_kernel(), flags, &lastaddr, &seg, first);
350 	}
351 	if (error == 0) {
352 		map->dm_mapsize = m0->m_pkthdr.len;
353 		map->dm_nsegs = seg + 1;
354 	}
355 	return (error);
356 }
357 
358 /*
359  * Like _bus_dmamap_load(), but for uios.
360  */
361 int
362 bus_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map,
363 	struct uio *uio, int flags)
364 {
365 	paddr_t lastaddr = 0;
366 	int seg, i, error, first;
367 	bus_size_t minlen, resid;
368 	struct iovec *iov;
369 	void *addr;
370 
371 	/*
372 	 * Make sure that on error condition we return "no valid mappings."
373 	 */
374 	map->dm_mapsize = 0;
375 	map->dm_nsegs = 0;
376 	KASSERT(map->dm_maxsegsz <= map->_dm_maxmaxsegsz);
377 
378 	resid = uio->uio_resid;
379 	iov = uio->uio_iov;
380 
381 	first = 1;
382 	seg = 0;
383 	error = 0;
384 	for (i = 0; i < uio->uio_iovcnt && resid != 0 && error == 0; i++) {
385 		/*
386 		 * Now at the first iovec to load.  Load each iovec
387 		 * until we have exhausted the residual count.
388 		 */
389 		minlen = resid < iov[i].iov_len ? resid : iov[i].iov_len;
390 		addr = (void *)iov[i].iov_base;
391 
392 		error = _bus_dmamap_load_buffer(t, map, addr, minlen,
393 		    uio->uio_vmspace, flags, &lastaddr, &seg, first);
394 		first = 0;
395 
396 		resid -= minlen;
397 	}
398 	if (error == 0) {
399 		map->dm_mapsize = uio->uio_resid;
400 		map->dm_nsegs = seg + 1;
401 	}
402 	return (error);
403 }
404 
405 /*
406  * Like _bus_dmamap_load(), but for raw memory allocated with
407  * bus_dmamem_alloc().
408  */
409 int
410 bus_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
411 	bus_dma_segment_t *segs, int nsegs, bus_size_t size, int flags)
412 {
413 
414 	panic("_bus_dmamap_load_raw: not implemented");
415 }
416 
417 /*
418  * Common function for unloading a DMA map.  May be called by
419  * chipset-specific DMA map unload functions.
420  */
421 void
422 bus_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
423 {
424 
425 	/*
426 	 * No resources to free; just mark the mappings as
427 	 * invalid.
428 	 */
429 	map->dm_maxsegsz = map->_dm_maxmaxsegsz;
430 	map->dm_mapsize = 0;
431 	map->dm_nsegs = 0;
432 }
433 
434 void
435 bus_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map,
436 	bus_addr_t offset, bus_size_t len, int ops)
437 {
438 
439 	/* XXX: this might need some MD tweaks */
440 	membar_sync();
441 }
442 
443 /*
444  * Common function for freeing DMA-safe memory.  May be called by
445  * bus-specific DMA memory free functions.
446  */
447 void
448 bus_dmamem_free(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs)
449 {
450 #ifdef RUMPCOMP_USERFEATURE_PCI_DMAFREE
451 	vaddr_t vacookie = segs[0]._ds_vacookie;
452 	bus_size_t sizecookie = segs[0]._ds_sizecookie;
453 
454 	rumpcomp_pci_dmafree(vacookie, sizecookie);
455 #else
456 	panic("bus_dmamem_free not implemented");
457 #endif
458 }
459 
460 /*
461  * Don't have hypercall for mapping scatter-gather memory.
462  * So just simply fail if there's more than one segment to map
463  */
464 int
465 bus_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
466 	size_t size, void **kvap, int flags)
467 {
468 	struct rumpcomp_pci_dmaseg *dss;
469 	size_t allocsize = nsegs * sizeof(*dss);
470 	int rv, i;
471 
472 	/*
473 	 * Though rumpcomp_pci_dmaseg "accidentally" matches the
474 	 * bus_dma segment descriptor (at least for now), act
475 	 * proper and actually translate it.
476 	 */
477 	dss = kmem_alloc(allocsize, KM_SLEEP);
478 	for (i = 0; i < nsegs; i++) {
479 		dss[i].ds_pa = segs[i].ds_addr;
480 		dss[i].ds_len = segs[i].ds_len;
481 		dss[i].ds_vacookie = segs[i]._ds_vacookie;
482 	}
483 	rv = rumpcomp_pci_dmamem_map(dss, nsegs, size, kvap);
484 	kmem_free(dss, allocsize);
485 
486 	return rv;
487 }
488 
489 /*
490  * Common function for unmapping DMA-safe memory.  May be called by
491  * bus-specific DMA memory unmapping functions.
492  */
493 void
494 bus_dmamem_unmap(bus_dma_tag_t t, void *kva, size_t size)
495 {
496 
497 	/* nothing to do as long as bus_dmamem_map() is what it is */
498 }
499 
500 paddr_t
501 bus_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
502 	off_t off, int prot, int flags)
503 {
504 
505 	panic("bus_dmamem_mmap not supported");
506 }
507 
508 /*
509  * Allocate physical memory from the given physical address range.
510  * Called by DMA-safe memory allocation methods.
511  */
512 int
513 bus_dmamem_alloc(bus_dma_tag_t t, bus_size_t size, bus_size_t alignment,
514 	bus_size_t boundary, bus_dma_segment_t *segs, int nsegs, int *rsegs,
515 	int flags)
516 {
517 	paddr_t curaddr, lastaddr, pa;
518 	vaddr_t vacookie;
519 	size_t sizecookie;
520 	int curseg, error;
521 
522 	/* Always round the size. */
523 	size = round_page(size);
524 
525 	sizecookie = size;
526 
527 	/*
528 	 * Allocate pages from the VM system.
529 	 */
530 #if 0
531 	error = uvm_pglistalloc(size, low, high, alignment, boundary,
532 	    &mlist, nsegs, (flags & BUS_DMA_NOWAIT) == 0);
533 #else
534 	/* XXX: ignores boundary, nsegs, etc. */
535 	//printf("dma allocation %lx %lx %d\n", alignment, boundary, nsegs);
536 	error = rumpcomp_pci_dmalloc(size, alignment, &pa, &vacookie);
537 #endif
538 	if (error)
539 		return (error);
540 
541 	/*
542 	 * Compute the location, size, and number of segments actually
543 	 * returned by the VM code.
544 	 */
545 	curseg = 0;
546 	lastaddr = segs[curseg].ds_addr = pa;
547 	segs[curseg].ds_len = PAGE_SIZE;
548 	segs[curseg]._ds_vacookie = vacookie;
549 	segs[curseg]._ds_sizecookie = sizecookie;
550 	size -= PAGE_SIZE;
551 	pa += PAGE_SIZE;
552 	vacookie += PAGE_SIZE;
553 
554 	for (; size;
555 	    pa += PAGE_SIZE, vacookie += PAGE_SIZE, size -= PAGE_SIZE) {
556 		curaddr = pa;
557 		if (curaddr == (lastaddr + PAGE_SIZE) &&
558 		    (lastaddr & boundary) == (curaddr & boundary)) {
559 			segs[curseg].ds_len += PAGE_SIZE;
560 		} else {
561 			curseg++;
562 			if (curseg >= nsegs)
563 				return EFBIG;
564 			segs[curseg].ds_addr = curaddr;
565 			segs[curseg].ds_len = PAGE_SIZE;
566 			segs[curseg]._ds_vacookie = vacookie;
567 			segs[curseg]._ds_sizecookie = sizecookie;
568 		}
569 		lastaddr = curaddr;
570 	}
571 	*rsegs = curseg + 1;
572 
573 	return (0);
574 }
575