1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2013 The FreeBSD Foundation
5 * All rights reserved.
6 *
7 * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
8 * under sponsorship from the FreeBSD Foundation.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33__FBSDID("$FreeBSD$");
34
35#include <sys/param.h>
36#include <sys/bus.h>
37#include <sys/kernel.h>
38#include <sys/lock.h>
39#include <sys/malloc.h>
40#include <sys/memdesc.h>
41#include <sys/mutex.h>
42#include <sys/proc.h>
43#include <sys/queue.h>
44#include <sys/rman.h>
45#include <sys/rwlock.h>
46#include <sys/sched.h>
47#include <sys/sf_buf.h>
48#include <sys/sysctl.h>
49#include <sys/systm.h>
50#include <sys/taskqueue.h>
51#include <sys/time.h>
52#include <sys/tree.h>
53#include <sys/vmem.h>
54#include <dev/pci/pcivar.h>
55#include <vm/vm.h>
56#include <vm/vm_extern.h>
57#include <vm/vm_kern.h>
58#include <vm/vm_object.h>
59#include <vm/vm_page.h>
60#include <vm/vm_map.h>
61#include <vm/vm_pageout.h>
62#include <machine/bus.h>
63#include <machine/cpu.h>
64#include <machine/intr_machdep.h>
65#include <x86/include/apicvar.h>
66#include <x86/include/busdma_impl.h>
67#include <x86/iommu/intel_reg.h>
68#include <x86/iommu/busdma_dmar.h>
69#include <dev/pci/pcireg.h>
70#include <x86/iommu/intel_dmar.h>
71
72u_int
73dmar_nd2mask(u_int nd)
74{
75	static const u_int masks[] = {
76		0x000f,	/* nd == 0 */
77		0x002f,	/* nd == 1 */
78		0x00ff,	/* nd == 2 */
79		0x02ff,	/* nd == 3 */
80		0x0fff,	/* nd == 4 */
81		0x2fff,	/* nd == 5 */
82		0xffff,	/* nd == 6 */
83		0x0000,	/* nd == 7 reserved */
84	};
85
86	KASSERT(nd <= 6, ("number of domains %d", nd));
87	return (masks[nd]);
88}
89
90static const struct sagaw_bits_tag {
91	int agaw;
92	int cap;
93	int awlvl;
94	int pglvl;
95} sagaw_bits[] = {
96	{.agaw = 30, .cap = DMAR_CAP_SAGAW_2LVL, .awlvl = DMAR_CTX2_AW_2LVL,
97	    .pglvl = 2},
98	{.agaw = 39, .cap = DMAR_CAP_SAGAW_3LVL, .awlvl = DMAR_CTX2_AW_3LVL,
99	    .pglvl = 3},
100	{.agaw = 48, .cap = DMAR_CAP_SAGAW_4LVL, .awlvl = DMAR_CTX2_AW_4LVL,
101	    .pglvl = 4},
102	{.agaw = 57, .cap = DMAR_CAP_SAGAW_5LVL, .awlvl = DMAR_CTX2_AW_5LVL,
103	    .pglvl = 5},
104	{.agaw = 64, .cap = DMAR_CAP_SAGAW_6LVL, .awlvl = DMAR_CTX2_AW_6LVL,
105	    .pglvl = 6}
106};
107
108bool
109dmar_pglvl_supported(struct dmar_unit *unit, int pglvl)
110{
111	int i;
112
113	for (i = 0; i < nitems(sagaw_bits); i++) {
114		if (sagaw_bits[i].pglvl != pglvl)
115			continue;
116		if ((DMAR_CAP_SAGAW(unit->hw_cap) & sagaw_bits[i].cap) != 0)
117			return (true);
118	}
119	return (false);
120}
121
122int
123domain_set_agaw(struct dmar_domain *domain, int mgaw)
124{
125	int sagaw, i;
126
127	domain->mgaw = mgaw;
128	sagaw = DMAR_CAP_SAGAW(domain->dmar->hw_cap);
129	for (i = 0; i < nitems(sagaw_bits); i++) {
130		if (sagaw_bits[i].agaw >= mgaw) {
131			domain->agaw = sagaw_bits[i].agaw;
132			domain->pglvl = sagaw_bits[i].pglvl;
133			domain->awlvl = sagaw_bits[i].awlvl;
134			return (0);
135		}
136	}
137	device_printf(domain->dmar->dev,
138	    "context request mgaw %d: no agaw found, sagaw %x\n",
139	    mgaw, sagaw);
140	return (EINVAL);
141}
142
143/*
144 * Find a best fit mgaw for the given maxaddr:
145 *   - if allow_less is false, must find sagaw which maps all requested
146 *     addresses (used by identity mappings);
147 *   - if allow_less is true, and no supported sagaw can map all requested
148 *     address space, accept the biggest sagaw, whatever is it.
149 */
150int
151dmar_maxaddr2mgaw(struct dmar_unit *unit, dmar_gaddr_t maxaddr, bool allow_less)
152{
153	int i;
154
155	for (i = 0; i < nitems(sagaw_bits); i++) {
156		if ((1ULL << sagaw_bits[i].agaw) >= maxaddr &&
157		    (DMAR_CAP_SAGAW(unit->hw_cap) & sagaw_bits[i].cap) != 0)
158			break;
159	}
160	if (allow_less && i == nitems(sagaw_bits)) {
161		do {
162			i--;
163		} while ((DMAR_CAP_SAGAW(unit->hw_cap) & sagaw_bits[i].cap)
164		    == 0);
165	}
166	if (i < nitems(sagaw_bits))
167		return (sagaw_bits[i].agaw);
168	KASSERT(0, ("no mgaw for maxaddr %jx allow_less %d",
169	    (uintmax_t) maxaddr, allow_less));
170	return (-1);
171}
172
173/*
174 * Calculate the total amount of page table pages needed to map the
175 * whole bus address space on the context with the selected agaw.
176 */
177vm_pindex_t
178pglvl_max_pages(int pglvl)
179{
180	vm_pindex_t res;
181	int i;
182
183	for (res = 0, i = pglvl; i > 0; i--) {
184		res *= DMAR_NPTEPG;
185		res++;
186	}
187	return (res);
188}
189
190/*
191 * Return true if the page table level lvl supports the superpage for
192 * the context ctx.
193 */
194int
195domain_is_sp_lvl(struct dmar_domain *domain, int lvl)
196{
197	int alvl, cap_sps;
198	static const int sagaw_sp[] = {
199		DMAR_CAP_SPS_2M,
200		DMAR_CAP_SPS_1G,
201		DMAR_CAP_SPS_512G,
202		DMAR_CAP_SPS_1T
203	};
204
205	alvl = domain->pglvl - lvl - 1;
206	cap_sps = DMAR_CAP_SPS(domain->dmar->hw_cap);
207	return (alvl < nitems(sagaw_sp) && (sagaw_sp[alvl] & cap_sps) != 0);
208}
209
210dmar_gaddr_t
211pglvl_page_size(int total_pglvl, int lvl)
212{
213	int rlvl;
214	static const dmar_gaddr_t pg_sz[] = {
215		(dmar_gaddr_t)DMAR_PAGE_SIZE,
216		(dmar_gaddr_t)DMAR_PAGE_SIZE << DMAR_NPTEPGSHIFT,
217		(dmar_gaddr_t)DMAR_PAGE_SIZE << (2 * DMAR_NPTEPGSHIFT),
218		(dmar_gaddr_t)DMAR_PAGE_SIZE << (3 * DMAR_NPTEPGSHIFT),
219		(dmar_gaddr_t)DMAR_PAGE_SIZE << (4 * DMAR_NPTEPGSHIFT),
220		(dmar_gaddr_t)DMAR_PAGE_SIZE << (5 * DMAR_NPTEPGSHIFT)
221	};
222
223	KASSERT(lvl >= 0 && lvl < total_pglvl,
224	    ("total %d lvl %d", total_pglvl, lvl));
225	rlvl = total_pglvl - lvl - 1;
226	KASSERT(rlvl < nitems(pg_sz), ("sizeof pg_sz lvl %d", lvl));
227	return (pg_sz[rlvl]);
228}
229
230dmar_gaddr_t
231domain_page_size(struct dmar_domain *domain, int lvl)
232{
233
234	return (pglvl_page_size(domain->pglvl, lvl));
235}
236
237int
238calc_am(struct dmar_unit *unit, dmar_gaddr_t base, dmar_gaddr_t size,
239    dmar_gaddr_t *isizep)
240{
241	dmar_gaddr_t isize;
242	int am;
243
244	for (am = DMAR_CAP_MAMV(unit->hw_cap);; am--) {
245		isize = 1ULL << (am + DMAR_PAGE_SHIFT);
246		if ((base & (isize - 1)) == 0 && size >= isize)
247			break;
248		if (am == 0)
249			break;
250	}
251	*isizep = isize;
252	return (am);
253}
254
255dmar_haddr_t dmar_high;
256int haw;
257int dmar_tbl_pagecnt;
258
259vm_page_t
260dmar_pgalloc(vm_object_t obj, vm_pindex_t idx, int flags)
261{
262	vm_page_t m;
263	int zeroed, aflags;
264
265	zeroed = (flags & DMAR_PGF_ZERO) != 0 ? VM_ALLOC_ZERO : 0;
266	aflags = zeroed | VM_ALLOC_NOBUSY | VM_ALLOC_SYSTEM | VM_ALLOC_NODUMP |
267	    ((flags & DMAR_PGF_WAITOK) != 0 ? VM_ALLOC_WAITFAIL :
268	    VM_ALLOC_NOWAIT);
269	for (;;) {
270		if ((flags & DMAR_PGF_OBJL) == 0)
271			VM_OBJECT_WLOCK(obj);
272		m = vm_page_lookup(obj, idx);
273		if ((flags & DMAR_PGF_NOALLOC) != 0 || m != NULL) {
274			if ((flags & DMAR_PGF_OBJL) == 0)
275				VM_OBJECT_WUNLOCK(obj);
276			break;
277		}
278		m = vm_page_alloc_contig(obj, idx, aflags, 1, 0,
279		    dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
280		if ((flags & DMAR_PGF_OBJL) == 0)
281			VM_OBJECT_WUNLOCK(obj);
282		if (m != NULL) {
283			if (zeroed && (m->flags & PG_ZERO) == 0)
284				pmap_zero_page(m);
285			atomic_add_int(&dmar_tbl_pagecnt, 1);
286			break;
287		}
288		if ((flags & DMAR_PGF_WAITOK) == 0)
289			break;
290	}
291	return (m);
292}
293
294void
295dmar_pgfree(vm_object_t obj, vm_pindex_t idx, int flags)
296{
297	vm_page_t m;
298
299	if ((flags & DMAR_PGF_OBJL) == 0)
300		VM_OBJECT_WLOCK(obj);
301	m = vm_page_lookup(obj, idx);
302	if (m != NULL) {
303		vm_page_free(m);
304		atomic_subtract_int(&dmar_tbl_pagecnt, 1);
305	}
306	if ((flags & DMAR_PGF_OBJL) == 0)
307		VM_OBJECT_WUNLOCK(obj);
308}
309
310void *
311dmar_map_pgtbl(vm_object_t obj, vm_pindex_t idx, int flags,
312    struct sf_buf **sf)
313{
314	vm_page_t m;
315	bool allocated;
316
317	if ((flags & DMAR_PGF_OBJL) == 0)
318		VM_OBJECT_WLOCK(obj);
319	m = vm_page_lookup(obj, idx);
320	if (m == NULL && (flags & DMAR_PGF_ALLOC) != 0) {
321		m = dmar_pgalloc(obj, idx, flags | DMAR_PGF_OBJL);
322		allocated = true;
323	} else
324		allocated = false;
325	if (m == NULL) {
326		if ((flags & DMAR_PGF_OBJL) == 0)
327			VM_OBJECT_WUNLOCK(obj);
328		return (NULL);
329	}
330	/* Sleepable allocations cannot fail. */
331	if ((flags & DMAR_PGF_WAITOK) != 0)
332		VM_OBJECT_WUNLOCK(obj);
333	sched_pin();
334	*sf = sf_buf_alloc(m, SFB_CPUPRIVATE | ((flags & DMAR_PGF_WAITOK)
335	    == 0 ? SFB_NOWAIT : 0));
336	if (*sf == NULL) {
337		sched_unpin();
338		if (allocated) {
339			VM_OBJECT_ASSERT_WLOCKED(obj);
340			dmar_pgfree(obj, m->pindex, flags | DMAR_PGF_OBJL);
341		}
342		if ((flags & DMAR_PGF_OBJL) == 0)
343			VM_OBJECT_WUNLOCK(obj);
344		return (NULL);
345	}
346	if ((flags & (DMAR_PGF_WAITOK | DMAR_PGF_OBJL)) ==
347	    (DMAR_PGF_WAITOK | DMAR_PGF_OBJL))
348		VM_OBJECT_WLOCK(obj);
349	else if ((flags & (DMAR_PGF_WAITOK | DMAR_PGF_OBJL)) == 0)
350		VM_OBJECT_WUNLOCK(obj);
351	return ((void *)sf_buf_kva(*sf));
352}
353
354void
355dmar_unmap_pgtbl(struct sf_buf *sf)
356{
357
358	sf_buf_free(sf);
359	sched_unpin();
360}
361
362static void
363dmar_flush_transl_to_ram(struct dmar_unit *unit, void *dst, size_t sz)
364{
365
366	if (DMAR_IS_COHERENT(unit))
367		return;
368	/*
369	 * If DMAR does not snoop paging structures accesses, flush
370	 * CPU cache to memory.
371	 */
372	pmap_force_invalidate_cache_range((uintptr_t)dst, (uintptr_t)dst + sz);
373}
374
375void
376dmar_flush_pte_to_ram(struct dmar_unit *unit, dmar_pte_t *dst)
377{
378
379	dmar_flush_transl_to_ram(unit, dst, sizeof(*dst));
380}
381
382void
383dmar_flush_ctx_to_ram(struct dmar_unit *unit, dmar_ctx_entry_t *dst)
384{
385
386	dmar_flush_transl_to_ram(unit, dst, sizeof(*dst));
387}
388
389void
390dmar_flush_root_to_ram(struct dmar_unit *unit, dmar_root_entry_t *dst)
391{
392
393	dmar_flush_transl_to_ram(unit, dst, sizeof(*dst));
394}
395
396/*
397 * Load the root entry pointer into the hardware, busily waiting for
398 * the completion.
399 */
400int
401dmar_load_root_entry_ptr(struct dmar_unit *unit)
402{
403	vm_page_t root_entry;
404	int error;
405
406	/*
407	 * Access to the GCMD register must be serialized while the
408	 * command is submitted.
409	 */
410	DMAR_ASSERT_LOCKED(unit);
411
412	VM_OBJECT_RLOCK(unit->ctx_obj);
413	root_entry = vm_page_lookup(unit->ctx_obj, 0);
414	VM_OBJECT_RUNLOCK(unit->ctx_obj);
415	dmar_write8(unit, DMAR_RTADDR_REG, VM_PAGE_TO_PHYS(root_entry));
416	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd | DMAR_GCMD_SRTP);
417	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_RTPS)
418	    != 0));
419	return (error);
420}
421
422/*
423 * Globally invalidate the context entries cache, busily waiting for
424 * the completion.
425 */
426int
427dmar_inv_ctx_glob(struct dmar_unit *unit)
428{
429	int error;
430
431	/*
432	 * Access to the CCMD register must be serialized while the
433	 * command is submitted.
434	 */
435	DMAR_ASSERT_LOCKED(unit);
436	KASSERT(!unit->qi_enabled, ("QI enabled"));
437
438	/*
439	 * The DMAR_CCMD_ICC bit in the upper dword should be written
440	 * after the low dword write is completed.  Amd64
441	 * dmar_write8() does not have this issue, i386 dmar_write8()
442	 * writes the upper dword last.
443	 */
444	dmar_write8(unit, DMAR_CCMD_REG, DMAR_CCMD_ICC | DMAR_CCMD_CIRG_GLOB);
445	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_CCMD_REG + 4) & DMAR_CCMD_ICC32)
446	    == 0));
447	return (error);
448}
449
450/*
451 * Globally invalidate the IOTLB, busily waiting for the completion.
452 */
453int
454dmar_inv_iotlb_glob(struct dmar_unit *unit)
455{
456	int error, reg;
457
458	DMAR_ASSERT_LOCKED(unit);
459	KASSERT(!unit->qi_enabled, ("QI enabled"));
460
461	reg = 16 * DMAR_ECAP_IRO(unit->hw_ecap);
462	/* See a comment about DMAR_CCMD_ICC in dmar_inv_ctx_glob. */
463	dmar_write8(unit, reg + DMAR_IOTLB_REG_OFF, DMAR_IOTLB_IVT |
464	    DMAR_IOTLB_IIRG_GLB | DMAR_IOTLB_DR | DMAR_IOTLB_DW);
465	DMAR_WAIT_UNTIL(((dmar_read4(unit, reg + DMAR_IOTLB_REG_OFF + 4) &
466	    DMAR_IOTLB_IVT32) == 0));
467	return (error);
468}
469
470/*
471 * Flush the chipset write buffers.  See 11.1 "Write Buffer Flushing"
472 * in the architecture specification.
473 */
474int
475dmar_flush_write_bufs(struct dmar_unit *unit)
476{
477	int error;
478
479	DMAR_ASSERT_LOCKED(unit);
480
481	/*
482	 * DMAR_GCMD_WBF is only valid when CAP_RWBF is reported.
483	 */
484	KASSERT((unit->hw_cap & DMAR_CAP_RWBF) != 0,
485	    ("dmar%d: no RWBF", unit->unit));
486
487	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd | DMAR_GCMD_WBF);
488	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_WBFS)
489	    != 0));
490	return (error);
491}
492
493int
494dmar_enable_translation(struct dmar_unit *unit)
495{
496	int error;
497
498	DMAR_ASSERT_LOCKED(unit);
499	unit->hw_gcmd |= DMAR_GCMD_TE;
500	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
501	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_TES)
502	    != 0));
503	return (error);
504}
505
506int
507dmar_disable_translation(struct dmar_unit *unit)
508{
509	int error;
510
511	DMAR_ASSERT_LOCKED(unit);
512	unit->hw_gcmd &= ~DMAR_GCMD_TE;
513	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
514	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_TES)
515	    == 0));
516	return (error);
517}
518
519int
520dmar_load_irt_ptr(struct dmar_unit *unit)
521{
522	uint64_t irta, s;
523	int error;
524
525	DMAR_ASSERT_LOCKED(unit);
526	irta = unit->irt_phys;
527	if (DMAR_X2APIC(unit))
528		irta |= DMAR_IRTA_EIME;
529	s = fls(unit->irte_cnt) - 2;
530	KASSERT(unit->irte_cnt >= 2 && s <= DMAR_IRTA_S_MASK &&
531	    powerof2(unit->irte_cnt),
532	    ("IRTA_REG_S overflow %x", unit->irte_cnt));
533	irta |= s;
534	dmar_write8(unit, DMAR_IRTA_REG, irta);
535	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd | DMAR_GCMD_SIRTP);
536	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_IRTPS)
537	    != 0));
538	return (error);
539}
540
541int
542dmar_enable_ir(struct dmar_unit *unit)
543{
544	int error;
545
546	DMAR_ASSERT_LOCKED(unit);
547	unit->hw_gcmd |= DMAR_GCMD_IRE;
548	unit->hw_gcmd &= ~DMAR_GCMD_CFI;
549	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
550	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_IRES)
551	    != 0));
552	return (error);
553}
554
555int
556dmar_disable_ir(struct dmar_unit *unit)
557{
558	int error;
559
560	DMAR_ASSERT_LOCKED(unit);
561	unit->hw_gcmd &= ~DMAR_GCMD_IRE;
562	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
563	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_IRES)
564	    == 0));
565	return (error);
566}
567
568#define BARRIER_F				\
569	u_int f_done, f_inproc, f_wakeup;	\
570						\
571	f_done = 1 << (barrier_id * 3);		\
572	f_inproc = 1 << (barrier_id * 3 + 1);	\
573	f_wakeup = 1 << (barrier_id * 3 + 2)
574
575bool
576dmar_barrier_enter(struct dmar_unit *dmar, u_int barrier_id)
577{
578	BARRIER_F;
579
580	DMAR_LOCK(dmar);
581	if ((dmar->barrier_flags & f_done) != 0) {
582		DMAR_UNLOCK(dmar);
583		return (false);
584	}
585
586	if ((dmar->barrier_flags & f_inproc) != 0) {
587		while ((dmar->barrier_flags & f_inproc) != 0) {
588			dmar->barrier_flags |= f_wakeup;
589			msleep(&dmar->barrier_flags, &dmar->lock, 0,
590			    "dmarb", 0);
591		}
592		KASSERT((dmar->barrier_flags & f_done) != 0,
593		    ("dmar%d barrier %d missing done", dmar->unit, barrier_id));
594		DMAR_UNLOCK(dmar);
595		return (false);
596	}
597
598	dmar->barrier_flags |= f_inproc;
599	DMAR_UNLOCK(dmar);
600	return (true);
601}
602
603void
604dmar_barrier_exit(struct dmar_unit *dmar, u_int barrier_id)
605{
606	BARRIER_F;
607
608	DMAR_ASSERT_LOCKED(dmar);
609	KASSERT((dmar->barrier_flags & (f_done | f_inproc)) == f_inproc,
610	    ("dmar%d barrier %d missed entry", dmar->unit, barrier_id));
611	dmar->barrier_flags |= f_done;
612	if ((dmar->barrier_flags & f_wakeup) != 0)
613		wakeup(&dmar->barrier_flags);
614	dmar->barrier_flags &= ~(f_inproc | f_wakeup);
615	DMAR_UNLOCK(dmar);
616}
617
618int dmar_batch_coalesce = 100;
619struct timespec dmar_hw_timeout = {
620	.tv_sec = 0,
621	.tv_nsec = 1000000
622};
623
624static const uint64_t d = 1000000000;
625
626void
627dmar_update_timeout(uint64_t newval)
628{
629
630	/* XXXKIB not atomic */
631	dmar_hw_timeout.tv_sec = newval / d;
632	dmar_hw_timeout.tv_nsec = newval % d;
633}
634
635uint64_t
636dmar_get_timeout(void)
637{
638
639	return ((uint64_t)dmar_hw_timeout.tv_sec * d +
640	    dmar_hw_timeout.tv_nsec);
641}
642
643static int
644dmar_timeout_sysctl(SYSCTL_HANDLER_ARGS)
645{
646	uint64_t val;
647	int error;
648
649	val = dmar_get_timeout();
650	error = sysctl_handle_long(oidp, &val, 0, req);
651	if (error != 0 || req->newptr == NULL)
652		return (error);
653	dmar_update_timeout(val);
654	return (error);
655}
656
657static SYSCTL_NODE(_hw, OID_AUTO, dmar, CTLFLAG_RD, NULL, "");
658SYSCTL_INT(_hw_dmar, OID_AUTO, tbl_pagecnt, CTLFLAG_RD,
659    &dmar_tbl_pagecnt, 0,
660    "Count of pages used for DMAR pagetables");
661SYSCTL_INT(_hw_dmar, OID_AUTO, batch_coalesce, CTLFLAG_RWTUN,
662    &dmar_batch_coalesce, 0,
663    "Number of qi batches between interrupt");
664SYSCTL_PROC(_hw_dmar, OID_AUTO, timeout,
665    CTLTYPE_U64 | CTLFLAG_RW | CTLFLAG_MPSAFE, 0, 0,
666    dmar_timeout_sysctl, "QU",
667    "Timeout for command wait, in nanoseconds");
668#ifdef INVARIANTS
669int dmar_check_free;
670SYSCTL_INT(_hw_dmar, OID_AUTO, check_free, CTLFLAG_RWTUN,
671    &dmar_check_free, 0,
672    "Check the GPA RBtree for free_down and free_after validity");
673#endif
674
675