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 "opt_acpi.h"
36
37#include <sys/param.h>
38#include <sys/bus.h>
39#include <sys/kernel.h>
40#include <sys/malloc.h>
41#include <sys/memdesc.h>
42#include <sys/module.h>
43#include <sys/rman.h>
44#include <sys/taskqueue.h>
45#include <sys/time.h>
46#include <sys/tree.h>
47#include <sys/vmem.h>
48#include <machine/bus.h>
49#include <contrib/dev/acpica/include/acpi.h>
50#include <contrib/dev/acpica/include/accommon.h>
51#include <dev/acpica/acpivar.h>
52#include <vm/vm.h>
53#include <vm/vm_extern.h>
54#include <vm/vm_kern.h>
55#include <vm/vm_page.h>
56#include <vm/vm_map.h>
57#include <machine/cpu.h>
58#include <x86/include/busdma_impl.h>
59#include <x86/iommu/intel_reg.h>
60#include <x86/iommu/busdma_dmar.h>
61#include <dev/pci/pcireg.h>
62#include <x86/iommu/intel_dmar.h>
63
64static bool
65dmar_qi_seq_processed(const struct dmar_unit *unit,
66    const struct dmar_qi_genseq *pseq)
67{
68
69	return (pseq->gen < unit->inv_waitd_gen ||
70	    (pseq->gen == unit->inv_waitd_gen &&
71	     pseq->seq <= unit->inv_waitd_seq_hw));
72}
73
74static int
75dmar_enable_qi(struct dmar_unit *unit)
76{
77	int error;
78
79	DMAR_ASSERT_LOCKED(unit);
80	unit->hw_gcmd |= DMAR_GCMD_QIE;
81	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
82	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
83	    != 0));
84	return (error);
85}
86
87static int
88dmar_disable_qi(struct dmar_unit *unit)
89{
90	int error;
91
92	DMAR_ASSERT_LOCKED(unit);
93	unit->hw_gcmd &= ~DMAR_GCMD_QIE;
94	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
95	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
96	    == 0));
97	return (error);
98}
99
100static void
101dmar_qi_advance_tail(struct dmar_unit *unit)
102{
103
104	DMAR_ASSERT_LOCKED(unit);
105	dmar_write4(unit, DMAR_IQT_REG, unit->inv_queue_tail);
106}
107
108static void
109dmar_qi_ensure(struct dmar_unit *unit, int descr_count)
110{
111	uint32_t head;
112	int bytes;
113
114	DMAR_ASSERT_LOCKED(unit);
115	bytes = descr_count << DMAR_IQ_DESCR_SZ_SHIFT;
116	for (;;) {
117		if (bytes <= unit->inv_queue_avail)
118			break;
119		/* refill */
120		head = dmar_read4(unit, DMAR_IQH_REG);
121		head &= DMAR_IQH_MASK;
122		unit->inv_queue_avail = head - unit->inv_queue_tail -
123		    DMAR_IQ_DESCR_SZ;
124		if (head <= unit->inv_queue_tail)
125			unit->inv_queue_avail += unit->inv_queue_size;
126		if (bytes <= unit->inv_queue_avail)
127			break;
128
129		/*
130		 * No space in the queue, do busy wait.  Hardware must
131		 * make a progress.  But first advance the tail to
132		 * inform the descriptor streamer about entries we
133		 * might have already filled, otherwise they could
134		 * clog the whole queue..
135		 */
136		dmar_qi_advance_tail(unit);
137		unit->inv_queue_full++;
138		cpu_spinwait();
139	}
140	unit->inv_queue_avail -= bytes;
141}
142
143static void
144dmar_qi_emit(struct dmar_unit *unit, uint64_t data1, uint64_t data2)
145{
146
147	DMAR_ASSERT_LOCKED(unit);
148	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data1;
149	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
150	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
151	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
152	    (uintmax_t)unit->inv_queue_size));
153	unit->inv_queue_tail &= unit->inv_queue_size - 1;
154	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data2;
155	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
156	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
157	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
158	    (uintmax_t)unit->inv_queue_size));
159	unit->inv_queue_tail &= unit->inv_queue_size - 1;
160}
161
162static void
163dmar_qi_emit_wait_descr(struct dmar_unit *unit, uint32_t seq, bool intr,
164    bool memw, bool fence)
165{
166
167	DMAR_ASSERT_LOCKED(unit);
168	dmar_qi_emit(unit, DMAR_IQ_DESCR_WAIT_ID |
169	    (intr ? DMAR_IQ_DESCR_WAIT_IF : 0) |
170	    (memw ? DMAR_IQ_DESCR_WAIT_SW : 0) |
171	    (fence ? DMAR_IQ_DESCR_WAIT_FN : 0) |
172	    (memw ? DMAR_IQ_DESCR_WAIT_SD(seq) : 0),
173	    memw ? unit->inv_waitd_seq_hw_phys : 0);
174}
175
176static void
177dmar_qi_emit_wait_seq(struct dmar_unit *unit, struct dmar_qi_genseq *pseq,
178    bool emit_wait)
179{
180	struct dmar_qi_genseq gsec;
181	uint32_t seq;
182
183	KASSERT(pseq != NULL, ("wait descriptor with no place for seq"));
184	DMAR_ASSERT_LOCKED(unit);
185	if (unit->inv_waitd_seq == 0xffffffff) {
186		gsec.gen = unit->inv_waitd_gen;
187		gsec.seq = unit->inv_waitd_seq;
188		dmar_qi_ensure(unit, 1);
189		dmar_qi_emit_wait_descr(unit, gsec.seq, false, true, false);
190		dmar_qi_advance_tail(unit);
191		while (!dmar_qi_seq_processed(unit, &gsec))
192			cpu_spinwait();
193		unit->inv_waitd_gen++;
194		unit->inv_waitd_seq = 1;
195	}
196	seq = unit->inv_waitd_seq++;
197	pseq->gen = unit->inv_waitd_gen;
198	pseq->seq = seq;
199	if (emit_wait) {
200		dmar_qi_ensure(unit, 1);
201		dmar_qi_emit_wait_descr(unit, seq, true, true, false);
202	}
203}
204
205static void
206dmar_qi_wait_for_seq(struct dmar_unit *unit, const struct dmar_qi_genseq *gseq,
207    bool nowait)
208{
209
210	DMAR_ASSERT_LOCKED(unit);
211	unit->inv_seq_waiters++;
212	while (!dmar_qi_seq_processed(unit, gseq)) {
213		if (cold || nowait) {
214			cpu_spinwait();
215		} else {
216			msleep(&unit->inv_seq_waiters, &unit->lock, 0,
217			    "dmarse", hz);
218		}
219	}
220	unit->inv_seq_waiters--;
221}
222
223void
224dmar_qi_invalidate_locked(struct dmar_domain *domain, dmar_gaddr_t base,
225    dmar_gaddr_t size, struct dmar_qi_genseq *pseq, bool emit_wait)
226{
227	struct dmar_unit *unit;
228	dmar_gaddr_t isize;
229	int am;
230
231	unit = domain->dmar;
232	DMAR_ASSERT_LOCKED(unit);
233	for (; size > 0; base += isize, size -= isize) {
234		am = calc_am(unit, base, size, &isize);
235		dmar_qi_ensure(unit, 1);
236		dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV |
237		    DMAR_IQ_DESCR_IOTLB_PAGE | DMAR_IQ_DESCR_IOTLB_DW |
238		    DMAR_IQ_DESCR_IOTLB_DR |
239		    DMAR_IQ_DESCR_IOTLB_DID(domain->domain),
240		    base | am);
241	}
242	dmar_qi_emit_wait_seq(unit, pseq, emit_wait);
243	dmar_qi_advance_tail(unit);
244}
245
246void
247dmar_qi_invalidate_ctx_glob_locked(struct dmar_unit *unit)
248{
249	struct dmar_qi_genseq gseq;
250
251	DMAR_ASSERT_LOCKED(unit);
252	dmar_qi_ensure(unit, 2);
253	dmar_qi_emit(unit, DMAR_IQ_DESCR_CTX_INV | DMAR_IQ_DESCR_CTX_GLOB, 0);
254	dmar_qi_emit_wait_seq(unit, &gseq, true);
255	dmar_qi_advance_tail(unit);
256	dmar_qi_wait_for_seq(unit, &gseq, false);
257}
258
259void
260dmar_qi_invalidate_iotlb_glob_locked(struct dmar_unit *unit)
261{
262	struct dmar_qi_genseq gseq;
263
264	DMAR_ASSERT_LOCKED(unit);
265	dmar_qi_ensure(unit, 2);
266	dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV | DMAR_IQ_DESCR_IOTLB_GLOB |
267	    DMAR_IQ_DESCR_IOTLB_DW | DMAR_IQ_DESCR_IOTLB_DR, 0);
268	dmar_qi_emit_wait_seq(unit, &gseq, true);
269	dmar_qi_advance_tail(unit);
270	dmar_qi_wait_for_seq(unit, &gseq, false);
271}
272
273void
274dmar_qi_invalidate_iec_glob(struct dmar_unit *unit)
275{
276	struct dmar_qi_genseq gseq;
277
278	DMAR_ASSERT_LOCKED(unit);
279	dmar_qi_ensure(unit, 2);
280	dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV, 0);
281	dmar_qi_emit_wait_seq(unit, &gseq, true);
282	dmar_qi_advance_tail(unit);
283	dmar_qi_wait_for_seq(unit, &gseq, false);
284}
285
286void
287dmar_qi_invalidate_iec(struct dmar_unit *unit, u_int start, u_int cnt)
288{
289	struct dmar_qi_genseq gseq;
290	u_int c, l;
291
292	DMAR_ASSERT_LOCKED(unit);
293	KASSERT(start < unit->irte_cnt && start < start + cnt &&
294	    start + cnt <= unit->irte_cnt,
295	    ("inv iec overflow %d %d %d", unit->irte_cnt, start, cnt));
296	for (; cnt > 0; cnt -= c, start += c) {
297		l = ffs(start | cnt) - 1;
298		c = 1 << l;
299		dmar_qi_ensure(unit, 1);
300		dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV |
301		    DMAR_IQ_DESCR_IEC_IDX | DMAR_IQ_DESCR_IEC_IIDX(start) |
302		    DMAR_IQ_DESCR_IEC_IM(l), 0);
303	}
304	dmar_qi_ensure(unit, 1);
305	dmar_qi_emit_wait_seq(unit, &gseq, true);
306	dmar_qi_advance_tail(unit);
307
308	/*
309	 * The caller of the function, in particular,
310	 * dmar_ir_program_irte(), may be called from the context
311	 * where the sleeping is forbidden (in fact, the
312	 * intr_table_lock mutex may be held, locked from
313	 * intr_shuffle_irqs()).  Wait for the invalidation completion
314	 * using the busy wait.
315	 *
316	 * The impact on the interrupt input setup code is small, the
317	 * expected overhead is comparable with the chipset register
318	 * read.  It is more harmful for the parallel DMA operations,
319	 * since we own the dmar unit lock until whole invalidation
320	 * queue is processed, which includes requests possibly issued
321	 * before our request.
322	 */
323	dmar_qi_wait_for_seq(unit, &gseq, true);
324}
325
326int
327dmar_qi_intr(void *arg)
328{
329	struct dmar_unit *unit;
330
331	unit = arg;
332	KASSERT(unit->qi_enabled, ("dmar%d: QI is not enabled", unit->unit));
333	taskqueue_enqueue(unit->qi_taskqueue, &unit->qi_task);
334	return (FILTER_HANDLED);
335}
336
337static void
338dmar_qi_task(void *arg, int pending __unused)
339{
340	struct dmar_unit *unit;
341	struct dmar_map_entry *entry;
342	uint32_t ics;
343
344	unit = arg;
345
346	DMAR_LOCK(unit);
347	for (;;) {
348		entry = TAILQ_FIRST(&unit->tlb_flush_entries);
349		if (entry == NULL)
350			break;
351		if (!dmar_qi_seq_processed(unit, &entry->gseq))
352			break;
353		TAILQ_REMOVE(&unit->tlb_flush_entries, entry, dmamap_link);
354		DMAR_UNLOCK(unit);
355		dmar_domain_free_entry(entry, (entry->flags &
356		    DMAR_MAP_ENTRY_QI_NF) == 0);
357		DMAR_LOCK(unit);
358	}
359	ics = dmar_read4(unit, DMAR_ICS_REG);
360	if ((ics & DMAR_ICS_IWC) != 0) {
361		ics = DMAR_ICS_IWC;
362		dmar_write4(unit, DMAR_ICS_REG, ics);
363	}
364	if (unit->inv_seq_waiters > 0)
365		wakeup(&unit->inv_seq_waiters);
366	DMAR_UNLOCK(unit);
367}
368
369int
370dmar_init_qi(struct dmar_unit *unit)
371{
372	uint64_t iqa;
373	uint32_t ics;
374	int qi_sz;
375
376	if (!DMAR_HAS_QI(unit) || (unit->hw_cap & DMAR_CAP_CM) != 0)
377		return (0);
378	unit->qi_enabled = 1;
379	TUNABLE_INT_FETCH("hw.dmar.qi", &unit->qi_enabled);
380	if (!unit->qi_enabled)
381		return (0);
382
383	TAILQ_INIT(&unit->tlb_flush_entries);
384	TASK_INIT(&unit->qi_task, 0, dmar_qi_task, unit);
385	unit->qi_taskqueue = taskqueue_create_fast("dmarqf", M_WAITOK,
386	    taskqueue_thread_enqueue, &unit->qi_taskqueue);
387	taskqueue_start_threads(&unit->qi_taskqueue, 1, PI_AV,
388	    "dmar%d qi taskq", unit->unit);
389
390	unit->inv_waitd_gen = 0;
391	unit->inv_waitd_seq = 1;
392
393	qi_sz = DMAR_IQA_QS_DEF;
394	TUNABLE_INT_FETCH("hw.dmar.qi_size", &qi_sz);
395	if (qi_sz > DMAR_IQA_QS_MAX)
396		qi_sz = DMAR_IQA_QS_MAX;
397	unit->inv_queue_size = (1ULL << qi_sz) * PAGE_SIZE;
398	/* Reserve one descriptor to prevent wraparound. */
399	unit->inv_queue_avail = unit->inv_queue_size - DMAR_IQ_DESCR_SZ;
400
401	/* The invalidation queue reads by DMARs are always coherent. */
402	unit->inv_queue = kmem_alloc_contig(unit->inv_queue_size, M_WAITOK |
403	    M_ZERO, 0, dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
404	unit->inv_waitd_seq_hw_phys = pmap_kextract(
405	    (vm_offset_t)&unit->inv_waitd_seq_hw);
406
407	DMAR_LOCK(unit);
408	dmar_write8(unit, DMAR_IQT_REG, 0);
409	iqa = pmap_kextract(unit->inv_queue);
410	iqa |= qi_sz;
411	dmar_write8(unit, DMAR_IQA_REG, iqa);
412	dmar_enable_qi(unit);
413	ics = dmar_read4(unit, DMAR_ICS_REG);
414	if ((ics & DMAR_ICS_IWC) != 0) {
415		ics = DMAR_ICS_IWC;
416		dmar_write4(unit, DMAR_ICS_REG, ics);
417	}
418	dmar_enable_qi_intr(unit);
419	DMAR_UNLOCK(unit);
420
421	return (0);
422}
423
424void
425dmar_fini_qi(struct dmar_unit *unit)
426{
427	struct dmar_qi_genseq gseq;
428
429	if (unit->qi_enabled)
430		return;
431	taskqueue_drain(unit->qi_taskqueue, &unit->qi_task);
432	taskqueue_free(unit->qi_taskqueue);
433	unit->qi_taskqueue = NULL;
434
435	DMAR_LOCK(unit);
436	/* quisce */
437	dmar_qi_ensure(unit, 1);
438	dmar_qi_emit_wait_seq(unit, &gseq, true);
439	dmar_qi_advance_tail(unit);
440	dmar_qi_wait_for_seq(unit, &gseq, false);
441	/* only after the quisce, disable queue */
442	dmar_disable_qi_intr(unit);
443	dmar_disable_qi(unit);
444	KASSERT(unit->inv_seq_waiters == 0,
445	    ("dmar%d: waiters on disabled queue", unit->unit));
446	DMAR_UNLOCK(unit);
447
448	kmem_free(unit->inv_queue, unit->inv_queue_size);
449	unit->inv_queue = 0;
450	unit->inv_queue_size = 0;
451	unit->qi_enabled = 0;
452}
453
454void
455dmar_enable_qi_intr(struct dmar_unit *unit)
456{
457	uint32_t iectl;
458
459	DMAR_ASSERT_LOCKED(unit);
460	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
461	iectl = dmar_read4(unit, DMAR_IECTL_REG);
462	iectl &= ~DMAR_IECTL_IM;
463	dmar_write4(unit, DMAR_IECTL_REG, iectl);
464}
465
466void
467dmar_disable_qi_intr(struct dmar_unit *unit)
468{
469	uint32_t iectl;
470
471	DMAR_ASSERT_LOCKED(unit);
472	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
473	iectl = dmar_read4(unit, DMAR_IECTL_REG);
474	dmar_write4(unit, DMAR_IECTL_REG, iectl | DMAR_IECTL_IM);
475}
476