xref: /netbsd-src/sys/arch/sparc/sparc/iommu.c (revision 97a098268db2f9af7b50d1d323f1b3454fba2c1b)
1 /*	$NetBSD: iommu.c,v 1.102 2023/12/01 05:22:01 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 1996
5  * 	The President and Fellows of Harvard College. All rights reserved.
6  * Copyright (c) 1995 	Paul Kranenburg
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by Aaron Brown and
19  *	Harvard University.
20  *	This product includes software developed by Paul Kranenburg.
21  * 4. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  */
38 
39 #include <sys/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: iommu.c,v 1.102 2023/12/01 05:22:01 thorpej Exp $");
41 
42 #include "opt_sparc_arch.h"
43 
44 #include <sys/param.h>
45 #include <sys/malloc.h>
46 #include <sys/queue.h>
47 #include <sys/systm.h>
48 #include <sys/device.h>
49 #include <sys/proc.h>
50 #include <sys/vmem.h>
51 
52 #include <uvm/uvm.h>
53 
54 #define _SPARC_BUS_DMA_PRIVATE
55 #include <sys/bus.h>
56 #include <machine/autoconf.h>
57 #include <machine/ctlreg.h>
58 #include <sparc/sparc/asm.h>
59 #include <sparc/sparc/vaddrs.h>
60 #include <sparc/sparc/cpuvar.h>
61 #include <sparc/sparc/iommureg.h>
62 #include <sparc/sparc/iommuvar.h>
63 
64 struct iommu_softc {
65 	struct iommureg	*sc_reg;
66 	u_int		sc_pagesize;
67 	u_int		sc_range;
68 	bus_addr_t	sc_dvmabase;
69 	iopte_t		*sc_ptes;
70 	int		sc_cachecoherent;
71 /*
72  * Note: operations on the extent map are being protected with
73  * splhigh(), since we cannot predict at which interrupt priority
74  * our clients will run.
75  */
76 	struct sparc_bus_dma_tag sc_dmatag;
77 	vmem_t *sc_dvmamap;
78 };
79 
80 /* autoconfiguration driver */
81 int	iommu_print(void *, const char *);
82 void	iommu_attach(device_t, device_t, void *);
83 int	iommu_match(device_t, cfdata_t, void *);
84 
85 #if defined(SUN4M)
86 static void iommu_copy_prom_entries(struct iommu_softc *);
87 #endif
88 
89 CFATTACH_DECL_NEW(iommu, sizeof(struct iommu_softc),
90     iommu_match, iommu_attach, NULL, NULL);
91 
92 /* IOMMU DMA map functions */
93 int	iommu_dmamap_create(bus_dma_tag_t, bus_size_t, int, bus_size_t,
94 			bus_size_t, int, bus_dmamap_t *);
95 int	iommu_dmamap_load(bus_dma_tag_t, bus_dmamap_t, void *,
96 			bus_size_t, struct proc *, int);
97 int	iommu_dmamap_load_mbuf(bus_dma_tag_t, bus_dmamap_t,
98 			struct mbuf *, int);
99 int	iommu_dmamap_load_uio(bus_dma_tag_t, bus_dmamap_t,
100 			struct uio *, int);
101 int	iommu_dmamap_load_raw(bus_dma_tag_t, bus_dmamap_t,
102 			bus_dma_segment_t *, int, bus_size_t, int);
103 void	iommu_dmamap_unload(bus_dma_tag_t, bus_dmamap_t);
104 void	iommu_dmamap_sync(bus_dma_tag_t, bus_dmamap_t, bus_addr_t,
105 			bus_size_t, int);
106 
107 int	iommu_dmamem_map(bus_dma_tag_t, bus_dma_segment_t *,
108 			int, size_t, void **, int);
109 void	iommu_dmamem_unmap(bus_dma_tag_t, void *, size_t);
110 paddr_t	iommu_dmamem_mmap(bus_dma_tag_t, bus_dma_segment_t *,
111 			int, off_t, int, int);
112 int	iommu_dvma_alloc(struct iommu_softc *, bus_dmamap_t, vaddr_t,
113 			 bus_size_t, int, bus_addr_t *, bus_size_t *);
114 
115 /*
116  * Print the location of some iommu-attached device (called just
117  * before attaching that device).  If `iommu' is not NULL, the
118  * device was found but not configured; print the iommu as well.
119  * Return UNCONF (config_find ignores this if the device was configured).
120  */
121 int
iommu_print(void * args,const char * iommu)122 iommu_print(void *args, const char *iommu)
123 {
124 	struct iommu_attach_args *ia = args;
125 
126 	if (iommu)
127 		aprint_normal("%s at %s", ia->iom_name, iommu);
128 	return (UNCONF);
129 }
130 
131 int
iommu_match(device_t parent,cfdata_t cf,void * aux)132 iommu_match(device_t parent, cfdata_t cf, void *aux)
133 {
134 	struct mainbus_attach_args *ma = aux;
135 
136 	if (CPU_ISSUN4 || CPU_ISSUN4C)
137 		return (0);
138 	return (strcmp(cf->cf_name, ma->ma_name) == 0);
139 }
140 
141 /*
142  * Attach the iommu.
143  */
144 void
iommu_attach(device_t parent,device_t self,void * aux)145 iommu_attach(device_t parent, device_t self, void *aux)
146 {
147 #if defined(SUN4M)
148 	struct iommu_softc *sc = device_private(self);
149 	struct mainbus_attach_args *ma = aux;
150 	struct sparc_bus_dma_tag *dmat = &sc->sc_dmatag;
151 	bus_space_handle_t bh;
152 	int node;
153 	int js1_implicit_iommu;
154 	int i, s;
155 	u_int iopte_table_pa;
156 	struct pglist mlist;
157 	u_int size;
158 	struct vm_page *m;
159 	vaddr_t va;
160 
161 	dmat->_cookie = sc;
162 	dmat->_dmamap_create = iommu_dmamap_create;
163 	dmat->_dmamap_destroy = _bus_dmamap_destroy;
164 	dmat->_dmamap_load = iommu_dmamap_load;
165 	dmat->_dmamap_load_mbuf = iommu_dmamap_load_mbuf;
166 	dmat->_dmamap_load_uio = iommu_dmamap_load_uio;
167 	dmat->_dmamap_load_raw = iommu_dmamap_load_raw;
168 	dmat->_dmamap_unload = iommu_dmamap_unload;
169 	dmat->_dmamap_sync = iommu_dmamap_sync;
170 
171 	dmat->_dmamem_alloc = _bus_dmamem_alloc;
172 	dmat->_dmamem_free = _bus_dmamem_free;
173 	dmat->_dmamem_map = iommu_dmamem_map;
174 	dmat->_dmamem_unmap = _bus_dmamem_unmap;
175 	dmat->_dmamem_mmap = iommu_dmamem_mmap;
176 
177 	/*
178 	 * JS1/OF device tree does not have an iommu node and sbus
179 	 * node is directly under root.  mainbus_attach detects this
180 	 * and calls us with sbus node instead so that we can attach
181 	 * implicit iommu and attach that sbus node under it.
182 	 */
183 	node = ma->ma_node;
184 	if (strcmp(prom_getpropstring(node, "name"), "sbus") == 0)
185 		js1_implicit_iommu = 1;
186 	else
187 		js1_implicit_iommu = 0;
188 
189 	/*
190 	 * Map registers into our space. The PROM may have done this
191 	 * already, but I feel better if we have our own copy. Plus, the
192 	 * prom doesn't map the entire register set.
193 	 *
194 	 * XXX struct iommureg is bigger than ra->ra_len; what are the
195 	 *     other fields for?
196 	 */
197 	if (bus_space_map(ma->ma_bustag, ma->ma_paddr,
198 			  sizeof(struct iommureg), 0, &bh) != 0) {
199 		printf("iommu_attach: cannot map registers\n");
200 		return;
201 	}
202 	sc->sc_reg = (struct iommureg *)bh;
203 
204 	sc->sc_cachecoherent = js1_implicit_iommu ? 0
205 				: node_has_property(node, "cache-coherence?");
206 	if (CACHEINFO.c_enabled == 0) /* XXX - is this correct? */
207 		sc->sc_cachecoherent = 0;
208 
209 	sc->sc_pagesize = js1_implicit_iommu ? PAGE_SIZE
210 				: prom_getpropint(node, "page-size", PAGE_SIZE),
211 
212 	/*
213 	 * Allocate memory for I/O pagetables.
214 	 * This takes 64K of contiguous physical memory to map 64M of
215 	 * DVMA space (starting at IOMMU_DVMA_BASE).
216 	 * The table must be aligned on a (-IOMMU_DVMA_BASE/pagesize)
217 	 * boundary (i.e. 64K for 64M of DVMA space).
218 	 */
219 
220 	size = ((0 - IOMMU_DVMA_BASE) / sc->sc_pagesize) * sizeof(iopte_t);
221 	if (uvm_pglistalloc(size, vm_first_phys, vm_first_phys+vm_num_phys,
222 			    size, 0, &mlist, 1, 0) != 0)
223 		panic("iommu_attach: no memory");
224 
225 	va = uvm_km_alloc(kernel_map, size, 0, UVM_KMF_VAONLY);
226 	if (va == 0)
227 		panic("iommu_attach: no memory");
228 
229 	sc->sc_ptes = (iopte_t *)va;
230 
231 	m = TAILQ_FIRST(&mlist);
232 	iopte_table_pa = VM_PAGE_TO_PHYS(m);
233 
234 	/* Map the pages */
235 	for (; m != NULL; m = TAILQ_NEXT(m,pageq.queue)) {
236 		paddr_t pa = VM_PAGE_TO_PHYS(m);
237 		pmap_kenter_pa(va, pa | PMAP_NC,
238 		    VM_PROT_READ | VM_PROT_WRITE, 0);
239 		va += PAGE_SIZE;
240 	}
241 	pmap_update(pmap_kernel());
242 
243 	/*
244 	 * Copy entries from current IOMMU table.
245 	 * XXX - Why do we need to do this?
246 	 */
247 	iommu_copy_prom_entries(sc);
248 
249 	/*
250 	 * Now we can install our new pagetable into the IOMMU
251 	 */
252 	sc->sc_range = 0 - IOMMU_DVMA_BASE;
253 	sc->sc_dvmabase = IOMMU_DVMA_BASE;
254 
255 	/* calculate log2(sc->sc_range/16MB) */
256 	i = ffs(sc->sc_range/(1 << 24)) - 1;
257 	if ((1 << i) != (sc->sc_range/(1 << 24)))
258 		panic("iommu: bad range: %d", i);
259 
260 	s = splhigh();
261 	IOMMU_FLUSHALL(sc);
262 
263 	/* Load range and physical address of PTEs */
264 	sc->sc_reg->io_cr = (sc->sc_reg->io_cr & ~IOMMU_CTL_RANGE) |
265 			  (i << IOMMU_CTL_RANGESHFT) | IOMMU_CTL_ME;
266 	sc->sc_reg->io_bar = (iopte_table_pa >> 4) & IOMMU_BAR_IBA;
267 
268 	IOMMU_FLUSHALL(sc);
269 	splx(s);
270 
271 	printf(": version 0x%x/0x%x, page-size %d, range %dMB\n",
272 		(sc->sc_reg->io_cr & IOMMU_CTL_VER) >> 24,
273 		(sc->sc_reg->io_cr & IOMMU_CTL_IMPL) >> 28,
274 		sc->sc_pagesize,
275 		sc->sc_range >> 20);
276 
277 	sc->sc_dvmamap = vmem_create("iommudvma",
278 				     IOMMU_DVMA_BASE,
279 				     IOMMU_DVMA_END - IOMMU_DVMA_BASE,
280 				     PAGE_SIZE,		/* quantum */
281 				     NULL,		/* importfn */
282 				     NULL,		/* releasefn */
283 				     NULL,		/* source */
284 				     0,			/* qcache_max */
285 				     VM_SLEEP,
286 				     IPL_VM);
287 
288 	devhandle_t selfh = device_handle(self);
289 
290 	/*
291 	 * If we are attaching implicit iommu on JS1/OF we do not have
292 	 * an iommu node to traverse, instead mainbus_attach passed us
293 	 * sbus node in ma.ma_node.  Attach it as the only iommu child.
294 	 */
295 	if (js1_implicit_iommu) {
296 		struct iommu_attach_args ia;
297 		struct openprom_addr sbus_iommu_reg = { 0, 0x10001000, 0x28 };
298 
299 		memset(&ia, 0, sizeof ia);
300 
301 		/* Propagate BUS & DMA tags */
302 		ia.iom_bustag = ma->ma_bustag;
303 		ia.iom_dmatag = &sc->sc_dmatag;
304 
305 		ia.iom_name = "sbus";
306 		ia.iom_node = node;
307 		ia.iom_reg = &sbus_iommu_reg;
308 		ia.iom_nreg = 1;
309 
310 		config_found(self, (void *)&ia, iommu_print,
311 		    CFARGS(.devhandle = prom_node_to_devhandle(selfh, node)));
312 		return;
313 	}
314 
315 	/*
316 	 * Loop through ROM children (expect Sbus among them).
317 	 */
318 	for (node = firstchild(node); node; node = nextsibling(node)) {
319 		struct iommu_attach_args ia;
320 
321 		memset(&ia, 0, sizeof ia);
322 		ia.iom_name = prom_getpropstring(node, "name");
323 
324 		/* Propagate BUS & DMA tags */
325 		ia.iom_bustag = ma->ma_bustag;
326 		ia.iom_dmatag = &sc->sc_dmatag;
327 
328 		ia.iom_node = node;
329 
330 		ia.iom_reg = NULL;
331 		prom_getprop(node, "reg", sizeof(struct openprom_addr),
332 			&ia.iom_nreg, &ia.iom_reg);
333 
334 		config_found(self, (void *)&ia, iommu_print,
335 		    CFARGS(.devhandle = prom_node_to_devhandle(selfh, node)));
336 		if (ia.iom_reg != NULL)
337 			free(ia.iom_reg, M_DEVBUF);
338 	}
339 #endif
340 }
341 
342 #if defined(SUN4M)
343 static void
iommu_copy_prom_entries(struct iommu_softc * sc)344 iommu_copy_prom_entries(struct iommu_softc *sc)
345 {
346 	u_int pbase, pa;
347 	u_int range;
348 	iopte_t *tpte_p;
349 	u_int pagesz = sc->sc_pagesize;
350 	int use_ac = (cpuinfo.cpu_impl == 4 && cpuinfo.mxcc);
351 	u_int mmupcr_save;
352 
353 	/*
354 	 * We read in the original table using MMU bypass and copy all
355 	 * of its entries to the appropriate place in our new table,
356 	 * even if the sizes are different.
357 	 * This is pretty easy since we know DVMA ends at 0xffffffff.
358 	 */
359 
360 	range = (1 << 24) <<
361 	    ((sc->sc_reg->io_cr & IOMMU_CTL_RANGE) >> IOMMU_CTL_RANGESHFT);
362 
363 	pbase = (sc->sc_reg->io_bar & IOMMU_BAR_IBA) <<
364 			(14 - IOMMU_BAR_IBASHFT);
365 
366 	if (use_ac) {
367 		/*
368 		 * Set MMU AC bit so we'll still read from the cache
369 		 * in by-pass mode.
370 		 */
371 		mmupcr_save = lda(SRMMU_PCR, ASI_SRMMU);
372 		sta(SRMMU_PCR, ASI_SRMMU, mmupcr_save | VIKING_PCR_AC);
373 	} else
374 		mmupcr_save = 0; /* XXX - avoid GCC `uninitialized' warning */
375 
376 	/* Flush entire IOMMU TLB before messing with the in-memory tables */
377 	IOMMU_FLUSHALL(sc);
378 
379 	/*
380 	 * tpte_p = top of our PTE table
381 	 * pa     = top of current PTE table
382 	 * Then work downwards and copy entries until we hit the bottom
383 	 * of either table.
384 	 */
385 	for (tpte_p = &sc->sc_ptes[((0 - IOMMU_DVMA_BASE)/pagesz) - 1],
386 	     pa = (u_int)pbase + (range/pagesz - 1)*sizeof(iopte_t);
387 	     tpte_p >= &sc->sc_ptes[0] && pa >= (u_int)pbase;
388 	     tpte_p--, pa -= sizeof(iopte_t)) {
389 
390 		*tpte_p = lda(pa, ASI_BYPASS);
391 	}
392 
393 	if (use_ac) {
394 		/* restore mmu after bug-avoidance */
395 		sta(SRMMU_PCR, ASI_SRMMU, mmupcr_save);
396 	}
397 }
398 #endif
399 
400 static void
iommu_enter(struct iommu_softc * sc,bus_addr_t dva,paddr_t pa)401 iommu_enter(struct iommu_softc *sc, bus_addr_t dva, paddr_t pa)
402 {
403 	int pte;
404 
405 	/* This routine relies on the fact that sc->sc_pagesize == PAGE_SIZE */
406 
407 #ifdef DIAGNOSTIC
408 	if (dva < sc->sc_dvmabase)
409 		panic("iommu_enter: dva 0x%lx not in DVMA space", (long)dva);
410 #endif
411 
412 	pte = atop(pa) << IOPTE_PPNSHFT;
413 	pte &= IOPTE_PPN;
414 	pte |= IOPTE_V | IOPTE_W | (sc->sc_cachecoherent ? IOPTE_C : 0);
415 	sc->sc_ptes[atop(dva - sc->sc_dvmabase)] = pte;
416 	IOMMU_FLUSHPAGE(sc, dva);
417 }
418 
419 /*
420  * iommu_remove: removes mappings created by iommu_enter
421  */
422 static void
iommu_remove(struct iommu_softc * sc,bus_addr_t dva,bus_size_t len)423 iommu_remove(struct iommu_softc *sc, bus_addr_t dva, bus_size_t len)
424 {
425 	u_int pagesz = sc->sc_pagesize;
426 	bus_addr_t base = sc->sc_dvmabase;
427 
428 #ifdef DEBUG
429 	if (dva < base)
430 		panic("iommu_remove: va 0x%lx not in DVMA space", (long)dva);
431 #endif
432 
433 	while ((long)len > 0) {
434 #ifdef notyet
435 #ifdef DEBUG
436 		if ((sc->sc_ptes[atop(dva - base)] & IOPTE_V) == 0)
437 			panic("iommu_remove: clearing invalid pte at dva 0x%lx",
438 			      (long)dva);
439 #endif
440 #endif
441 		sc->sc_ptes[atop(dva - base)] = 0;
442 		IOMMU_FLUSHPAGE(sc, dva);
443 		len -= pagesz;
444 		dva += pagesz;
445 	}
446 }
447 
448 #if 0	/* These registers aren't there??? */
449 void
450 iommu_error(void)
451 {
452 	struct iommu_softc *sc = X;
453 	struct iommureg *iop = sc->sc_reg;
454 
455 	printf("iommu: afsr 0x%x, afar 0x%x\n", iop->io_afsr, iop->io_afar);
456 	printf("iommu: mfsr 0x%x, mfar 0x%x\n", iop->io_mfsr, iop->io_mfar);
457 }
458 
459 int
460 iommu_alloc(u_int va, u_int len)
461 {
462 	struct iommu_softc *sc = X;
463 	int off, tva, iovaddr, pte;
464 	paddr_t pa;
465 
466 	off = (int)va & PGOFSET;
467 	len = round_page(len + off);
468 	va -= off;
469 
470 if ((int)sc->sc_dvmacur + len > 0)
471 	sc->sc_dvmacur = sc->sc_dvmabase;
472 
473 	iovaddr = tva = sc->sc_dvmacur;
474 	sc->sc_dvmacur += len;
475 	while (len) {
476 		(void) pmap_extract(pmap_kernel(), va, &pa);
477 
478 #define IOMMU_PPNSHIFT	8
479 #define IOMMU_V		0x00000002
480 #define IOMMU_W		0x00000004
481 
482 		pte = atop(pa) << IOMMU_PPNSHIFT;
483 		pte |= IOMMU_V | IOMMU_W;
484 		sta(sc->sc_ptes + atop(tva - sc->sc_dvmabase), ASI_BYPASS, pte);
485 		sc->sc_reg->io_flushpage = tva;
486 		len -= PAGE_SIZE;
487 		va += PAGE_SIZE;
488 		tva += PAGE_SIZE;
489 	}
490 	return iovaddr + off;
491 }
492 #endif
493 
494 
495 /*
496  * IOMMU DMA map functions.
497  */
498 int
iommu_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)499 iommu_dmamap_create(bus_dma_tag_t t, bus_size_t size, int nsegments,
500 		    bus_size_t maxsegsz, bus_size_t boundary, int flags,
501 		    bus_dmamap_t *dmamp)
502 {
503 	bus_dmamap_t map;
504 	int error;
505 
506 	if ((error = _bus_dmamap_create(t, size, nsegments, maxsegsz,
507 					boundary, flags, &map)) != 0)
508 		return (error);
509 
510 	if ((flags & BUS_DMA_24BIT) != 0) {
511 		/* Limit this map to the range usable by `24-bit' devices */
512 		map->_dm_ex_start = D24_DVMA_BASE;
513 		map->_dm_ex_end = D24_DVMA_END - 1;
514 	} else {
515 		/* Enable allocations from the entire map */
516 		map->_dm_ex_start = VMEM_ADDR_MIN;
517 		map->_dm_ex_end = VMEM_ADDR_MAX;
518 	}
519 
520 	*dmamp = map;
521 	return (0);
522 }
523 
524 /*
525  * Internal routine to allocate space in the IOMMU map.
526  */
527 int
iommu_dvma_alloc(struct iommu_softc * sc,bus_dmamap_t map,vaddr_t va,bus_size_t len,int flags,bus_addr_t * dvap,bus_size_t * sgsizep)528 iommu_dvma_alloc(struct iommu_softc *sc, bus_dmamap_t map,
529 		 vaddr_t va, bus_size_t len, int flags,
530 		 bus_addr_t *dvap, bus_size_t *sgsizep)
531 {
532 	bus_size_t sgsize;
533 	u_long align, voff;
534 	vmem_addr_t dvaddr;
535 	int error;
536 	int pagesz = PAGE_SIZE;
537 
538 	/*
539 	 * Remember page offset, then truncate the buffer address to
540 	 * a page boundary.
541 	 */
542 	voff = va & (pagesz - 1);
543 	va &= -pagesz;
544 
545 	if (len > map->_dm_size)
546 		return (EINVAL);
547 
548 	sgsize = (len + voff + pagesz - 1) & -pagesz;
549 	align = dvma_cachealign ? dvma_cachealign : map->_dm_align;
550 
551 	const vm_flag_t vmflags = VM_BESTFIT |
552 	    ((flags & BUS_DMA_NOWAIT) ? VM_NOSLEEP : VM_SLEEP);
553 
554 	error = vmem_xalloc(sc->sc_dvmamap, sgsize,
555 			    align,			/* alignment */
556 			    va & (align-1),		/* phase */
557 			    map->_dm_boundary,		/* nocross */
558 			    map->_dm_ex_start,		/* minaddr */
559 			    map->_dm_ex_end,		/* maxaddr */
560 			    vmflags,
561 			    &dvaddr);
562 
563 	*dvap = (bus_addr_t)dvaddr;
564 	*sgsizep = sgsize;
565 	return (error);
566 }
567 
568 /*
569  * Prepare buffer for DMA transfer.
570  */
571 int
iommu_dmamap_load(bus_dma_tag_t t,bus_dmamap_t map,void * buf,bus_size_t buflen,struct proc * p,int flags)572 iommu_dmamap_load(bus_dma_tag_t t, bus_dmamap_t map,
573 		  void *buf, bus_size_t buflen,
574 		  struct proc *p, int flags)
575 {
576 	struct iommu_softc *sc = t->_cookie;
577 	bus_size_t sgsize;
578 	bus_addr_t dva;
579 	vaddr_t va = (vaddr_t)buf;
580 	int pagesz = PAGE_SIZE;
581 	pmap_t pmap;
582 	int error;
583 
584 	/*
585 	 * Make sure that on error condition we return "no valid mappings".
586 	 */
587 	map->dm_nsegs = 0;
588 
589 	/* Allocate IOMMU resources */
590 	if ((error = iommu_dvma_alloc(sc, map, va, buflen, flags,
591 					&dva, &sgsize)) != 0)
592 		return (error);
593 
594 	if ((sc->sc_cachecoherent == 0) ||
595 	    (curcpu()->cacheinfo.ec_totalsize == 0))
596 		cache_flush(buf, buflen); /* XXX - move to bus_dma_sync? */
597 
598 	/*
599 	 * We always use just one segment.
600 	 */
601 	map->dm_mapsize = buflen;
602 	map->dm_nsegs = 1;
603 	map->dm_segs[0].ds_addr = dva + (va & (pagesz - 1));
604 	map->dm_segs[0].ds_len = buflen;
605 	map->dm_segs[0]._ds_sgsize = sgsize;
606 
607 	if (p != NULL)
608 		pmap = p->p_vmspace->vm_map.pmap;
609 	else
610 		pmap = pmap_kernel();
611 
612 	for (; sgsize != 0; ) {
613 		paddr_t pa;
614 		/*
615 		 * Get the physical address for this page.
616 		 */
617 		if (!pmap_extract(pmap, va, &pa)) {
618 			iommu_dmamap_unload(t, map);
619 			return (EFAULT);
620 		}
621 
622 		iommu_enter(sc, dva, pa);
623 
624 		dva += pagesz;
625 		va += pagesz;
626 		sgsize -= pagesz;
627 	}
628 
629 	return (0);
630 }
631 
632 /*
633  * Like _bus_dmamap_load(), but for mbufs.
634  */
635 int
iommu_dmamap_load_mbuf(bus_dma_tag_t t,bus_dmamap_t map,struct mbuf * m,int flags)636 iommu_dmamap_load_mbuf(bus_dma_tag_t t, bus_dmamap_t map,
637 		       struct mbuf *m, int flags)
638 {
639 
640 	panic("_bus_dmamap_load_mbuf: not implemented");
641 }
642 
643 /*
644  * Like _bus_dmamap_load(), but for uios.
645  */
646 int
iommu_dmamap_load_uio(bus_dma_tag_t t,bus_dmamap_t map,struct uio * uio,int flags)647 iommu_dmamap_load_uio(bus_dma_tag_t t, bus_dmamap_t map,
648 		      struct uio *uio, int flags)
649 {
650 
651 	panic("_bus_dmamap_load_uio: not implemented");
652 }
653 
654 /*
655  * Like _bus_dmamap_load(), but for raw memory allocated with
656  * bus_dmamem_alloc().
657  */
658 int
iommu_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)659 iommu_dmamap_load_raw(bus_dma_tag_t t, bus_dmamap_t map,
660 		      bus_dma_segment_t *segs, int nsegs, bus_size_t size,
661 		      int flags)
662 {
663 	struct iommu_softc *sc = t->_cookie;
664 	struct vm_page *m;
665 	paddr_t pa;
666 	bus_addr_t dva;
667 	bus_size_t sgsize;
668 	struct pglist *mlist;
669 	int pagesz = PAGE_SIZE;
670 	int error;
671 
672 	map->dm_nsegs = 0;
673 
674 	/* Allocate IOMMU resources */
675 	if ((error = iommu_dvma_alloc(sc, map, segs[0]._ds_va, size,
676 				      flags, &dva, &sgsize)) != 0)
677 		return (error);
678 
679 	/*
680 	 * Note DVMA address in case bus_dmamem_map() is called later.
681 	 * It can then insure cache coherency by choosing a KVA that
682 	 * is aligned to `ds_addr'.
683 	 */
684 	segs[0].ds_addr = dva;
685 	segs[0].ds_len = size;
686 
687 	map->dm_segs[0].ds_addr = dva;
688 	map->dm_segs[0].ds_len = size;
689 	map->dm_segs[0]._ds_sgsize = sgsize;
690 
691 	/* Map physical pages into IOMMU */
692 	mlist = segs[0]._ds_mlist;
693 	for (m = TAILQ_FIRST(mlist); m != NULL; m = TAILQ_NEXT(m,pageq.queue)) {
694 		if (sgsize == 0)
695 			panic("iommu_dmamap_load_raw: size botch");
696 		pa = VM_PAGE_TO_PHYS(m);
697 		iommu_enter(sc, dva, pa);
698 		dva += pagesz;
699 		sgsize -= pagesz;
700 	}
701 
702 	map->dm_nsegs = 1;
703 	map->dm_mapsize = size;
704 
705 	return (0);
706 }
707 
708 /*
709  * Unload an IOMMU DMA map.
710  */
711 void
iommu_dmamap_unload(bus_dma_tag_t t,bus_dmamap_t map)712 iommu_dmamap_unload(bus_dma_tag_t t, bus_dmamap_t map)
713 {
714 	struct iommu_softc *sc = t->_cookie;
715 	bus_dma_segment_t *segs = map->dm_segs;
716 	int nsegs = map->dm_nsegs;
717 	bus_addr_t dva;
718 	bus_size_t len;
719 	int i;
720 
721 	for (i = 0; i < nsegs; i++) {
722 		dva = segs[i].ds_addr & -PAGE_SIZE;
723 		len = segs[i]._ds_sgsize;
724 
725 		iommu_remove(sc, dva, len);
726 		vmem_xfree(sc->sc_dvmamap, dva, len);
727 	}
728 
729 	/* Mark the mappings as invalid. */
730 	map->dm_mapsize = 0;
731 	map->dm_nsegs = 0;
732 }
733 
734 /*
735  * DMA map synchronization.
736  */
737 void
iommu_dmamap_sync(bus_dma_tag_t t,bus_dmamap_t map,bus_addr_t offset,bus_size_t len,int ops)738 iommu_dmamap_sync(bus_dma_tag_t t, bus_dmamap_t map,
739 		  bus_addr_t offset, bus_size_t len, int ops)
740 {
741 
742 	/*
743 	 * XXX Should flush CPU write buffers.
744 	 */
745 }
746 
747 /*
748  * Map DMA-safe memory.
749  */
750 int
iommu_dmamem_map(bus_dma_tag_t t,bus_dma_segment_t * segs,int nsegs,size_t size,void ** kvap,int flags)751 iommu_dmamem_map(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
752 		 size_t size, void **kvap, int flags)
753 {
754 	struct iommu_softc *sc = t->_cookie;
755 	struct vm_page *m;
756 	vaddr_t va;
757 	bus_addr_t addr;
758 	struct pglist *mlist;
759 	int cbit;
760 	u_long align;
761 	int pagesz = PAGE_SIZE;
762 
763 	if (nsegs != 1)
764 		panic("iommu_dmamem_map: nsegs = %d", nsegs);
765 
766 	cbit = sc->sc_cachecoherent ? 0 : PMAP_NC;
767 	align = dvma_cachealign ? dvma_cachealign : pagesz;
768 
769 	size = round_page(size);
770 
771 	/*
772 	 * In case the segment has already been loaded by
773 	 * iommu_dmamap_load_raw(), find a region of kernel virtual
774 	 * addresses that can accommodate our alignment requirements.
775 	 */
776 	va = _bus_dma_valloc_skewed(size, 0, align,
777 				    segs[0].ds_addr & (align - 1));
778 	if (va == 0)
779 		return (ENOMEM);
780 
781 	segs[0]._ds_va = va;
782 	*kvap = (void *)va;
783 
784 	/*
785 	 * Map the pages allocated in _bus_dmamem_alloc() to the
786 	 * kernel virtual address space.
787 	 */
788 	mlist = segs[0]._ds_mlist;
789 	for (m = TAILQ_FIRST(mlist); m != NULL; m = TAILQ_NEXT(m,pageq.queue)) {
790 
791 		if (size == 0)
792 			panic("iommu_dmamem_map: size botch");
793 
794 		addr = VM_PAGE_TO_PHYS(m);
795 		pmap_kenter_pa(va, addr | cbit,
796 		    VM_PROT_READ | VM_PROT_WRITE, 0);
797 #if 0
798 			if (flags & BUS_DMA_COHERENT)
799 				/* XXX */;
800 #endif
801 		va += pagesz;
802 		size -= pagesz;
803 	}
804 	pmap_update(pmap_kernel());
805 
806 	return (0);
807 }
808 
809 void
iommu_dmamem_unmap(bus_dma_tag_t t,void * kva,size_t size)810 iommu_dmamem_unmap(bus_dma_tag_t t, void *kva, size_t size)
811 {
812 
813 #ifdef DIAGNOSTIC
814 	if ((u_long)kva & PAGE_MASK)
815 		panic("iommu_dmamem_unmap");
816 #endif
817 
818 	size = round_page(size);
819 	pmap_kremove((vaddr_t)kva, size);
820 	pmap_update(pmap_kernel());
821 	uvm_unmap(kernel_map, (vaddr_t)kva, (vaddr_t)kva + size);
822 }
823 
824 
825 /*
826  * mmap(2)'ing DMA-safe memory.
827  */
828 paddr_t
iommu_dmamem_mmap(bus_dma_tag_t t,bus_dma_segment_t * segs,int nsegs,off_t off,int prot,int flags)829 iommu_dmamem_mmap(bus_dma_tag_t t, bus_dma_segment_t *segs, int nsegs,
830 		  off_t off, int prot, int flags)
831 {
832 
833 	panic("_bus_dmamem_mmap: not implemented");
834 }
835