1/*-
2 * Copyright (c) 2013 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
6 * under sponsorship from the FreeBSD Foundation.
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 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD: stable/11/sys/x86/iommu/intel_qi.c 320357 2017-06-26 12:30:39Z kib $");
32
33#include "opt_acpi.h"
34
35#include <sys/param.h>
36#include <sys/bus.h>
37#include <sys/kernel.h>
38#include <sys/malloc.h>
39#include <sys/memdesc.h>
40#include <sys/module.h>
41#include <sys/rman.h>
42#include <sys/taskqueue.h>
43#include <sys/time.h>
44#include <sys/tree.h>
45#include <sys/vmem.h>
46#include <machine/bus.h>
47#include <contrib/dev/acpica/include/acpi.h>
48#include <contrib/dev/acpica/include/accommon.h>
49#include <dev/acpica/acpivar.h>
50#include <vm/vm.h>
51#include <vm/vm_extern.h>
52#include <vm/vm_kern.h>
53#include <vm/vm_page.h>
54#include <vm/vm_map.h>
55#include <machine/cpu.h>
56#include <x86/include/busdma_impl.h>
57#include <x86/iommu/intel_reg.h>
58#include <x86/iommu/busdma_dmar.h>
59#include <x86/iommu/intel_dmar.h>
60
61static bool
62dmar_qi_seq_processed(const struct dmar_unit *unit,
63    const struct dmar_qi_genseq *pseq)
64{
65
66	return (pseq->gen < unit->inv_waitd_gen ||
67	    (pseq->gen == unit->inv_waitd_gen &&
68	     pseq->seq <= unit->inv_waitd_seq_hw));
69}
70
71static int
72dmar_enable_qi(struct dmar_unit *unit)
73{
74	int error;
75
76	DMAR_ASSERT_LOCKED(unit);
77	unit->hw_gcmd |= DMAR_GCMD_QIE;
78	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
79	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
80	    != 0));
81	return (error);
82}
83
84static int
85dmar_disable_qi(struct dmar_unit *unit)
86{
87	int error;
88
89	DMAR_ASSERT_LOCKED(unit);
90	unit->hw_gcmd &= ~DMAR_GCMD_QIE;
91	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
92	DMAR_WAIT_UNTIL(((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES)
93	    == 0));
94	return (error);
95}
96
97static void
98dmar_qi_advance_tail(struct dmar_unit *unit)
99{
100
101	DMAR_ASSERT_LOCKED(unit);
102	dmar_write4(unit, DMAR_IQT_REG, unit->inv_queue_tail);
103}
104
105static void
106dmar_qi_ensure(struct dmar_unit *unit, int descr_count)
107{
108	uint32_t head;
109	int bytes;
110
111	DMAR_ASSERT_LOCKED(unit);
112	bytes = descr_count << DMAR_IQ_DESCR_SZ_SHIFT;
113	for (;;) {
114		if (bytes <= unit->inv_queue_avail)
115			break;
116		/* refill */
117		head = dmar_read4(unit, DMAR_IQH_REG);
118		head &= DMAR_IQH_MASK;
119		unit->inv_queue_avail = head - unit->inv_queue_tail -
120		    DMAR_IQ_DESCR_SZ;
121		if (head <= unit->inv_queue_tail)
122			unit->inv_queue_avail += unit->inv_queue_size;
123		if (bytes <= unit->inv_queue_avail)
124			break;
125
126		/*
127		 * No space in the queue, do busy wait.  Hardware must
128		 * make a progress.  But first advance the tail to
129		 * inform the descriptor streamer about entries we
130		 * might have already filled, otherwise they could
131		 * clog the whole queue..
132		 */
133		dmar_qi_advance_tail(unit);
134		unit->inv_queue_full++;
135		cpu_spinwait();
136	}
137	unit->inv_queue_avail -= bytes;
138}
139
140static void
141dmar_qi_emit(struct dmar_unit *unit, uint64_t data1, uint64_t data2)
142{
143
144	DMAR_ASSERT_LOCKED(unit);
145	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data1;
146	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
147	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
148	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
149	    (uintmax_t)unit->inv_queue_size));
150	unit->inv_queue_tail &= unit->inv_queue_size - 1;
151	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data2;
152	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
153	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
154	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
155	    (uintmax_t)unit->inv_queue_size));
156	unit->inv_queue_tail &= unit->inv_queue_size - 1;
157}
158
159static void
160dmar_qi_emit_wait_descr(struct dmar_unit *unit, uint32_t seq, bool intr,
161    bool memw, bool fence)
162{
163
164	DMAR_ASSERT_LOCKED(unit);
165	dmar_qi_emit(unit, DMAR_IQ_DESCR_WAIT_ID |
166	    (intr ? DMAR_IQ_DESCR_WAIT_IF : 0) |
167	    (memw ? DMAR_IQ_DESCR_WAIT_SW : 0) |
168	    (fence ? DMAR_IQ_DESCR_WAIT_FN : 0) |
169	    (memw ? DMAR_IQ_DESCR_WAIT_SD(seq) : 0),
170	    memw ? unit->inv_waitd_seq_hw_phys : 0);
171}
172
173static void
174dmar_qi_emit_wait_seq(struct dmar_unit *unit, struct dmar_qi_genseq *pseq,
175    bool emit_wait)
176{
177	struct dmar_qi_genseq gsec;
178	uint32_t seq;
179
180	KASSERT(pseq != NULL, ("wait descriptor with no place for seq"));
181	DMAR_ASSERT_LOCKED(unit);
182	if (unit->inv_waitd_seq == 0xffffffff) {
183		gsec.gen = unit->inv_waitd_gen;
184		gsec.seq = unit->inv_waitd_seq;
185		dmar_qi_ensure(unit, 1);
186		dmar_qi_emit_wait_descr(unit, gsec.seq, false, true, false);
187		dmar_qi_advance_tail(unit);
188		while (!dmar_qi_seq_processed(unit, &gsec))
189			cpu_spinwait();
190		unit->inv_waitd_gen++;
191		unit->inv_waitd_seq = 1;
192	}
193	seq = unit->inv_waitd_seq++;
194	pseq->gen = unit->inv_waitd_gen;
195	pseq->seq = seq;
196	if (emit_wait) {
197		dmar_qi_ensure(unit, 1);
198		dmar_qi_emit_wait_descr(unit, seq, true, true, false);
199	}
200}
201
202static void
203dmar_qi_wait_for_seq(struct dmar_unit *unit, const struct dmar_qi_genseq *gseq,
204    bool nowait)
205{
206
207	DMAR_ASSERT_LOCKED(unit);
208	unit->inv_seq_waiters++;
209	while (!dmar_qi_seq_processed(unit, gseq)) {
210		if (cold || nowait) {
211			cpu_spinwait();
212		} else {
213			msleep(&unit->inv_seq_waiters, &unit->lock, 0,
214			    "dmarse", hz);
215		}
216	}
217	unit->inv_seq_waiters--;
218}
219
220void
221dmar_qi_invalidate_locked(struct dmar_domain *domain, dmar_gaddr_t base,
222    dmar_gaddr_t size, struct dmar_qi_genseq *pseq, bool emit_wait)
223{
224	struct dmar_unit *unit;
225	dmar_gaddr_t isize;
226	int am;
227
228	unit = domain->dmar;
229	DMAR_ASSERT_LOCKED(unit);
230	for (; size > 0; base += isize, size -= isize) {
231		am = calc_am(unit, base, size, &isize);
232		dmar_qi_ensure(unit, 1);
233		dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV |
234		    DMAR_IQ_DESCR_IOTLB_PAGE | DMAR_IQ_DESCR_IOTLB_DW |
235		    DMAR_IQ_DESCR_IOTLB_DR |
236		    DMAR_IQ_DESCR_IOTLB_DID(domain->domain),
237		    base | am);
238	}
239	dmar_qi_emit_wait_seq(unit, pseq, emit_wait);
240	dmar_qi_advance_tail(unit);
241}
242
243void
244dmar_qi_invalidate_ctx_glob_locked(struct dmar_unit *unit)
245{
246	struct dmar_qi_genseq gseq;
247
248	DMAR_ASSERT_LOCKED(unit);
249	dmar_qi_ensure(unit, 2);
250	dmar_qi_emit(unit, DMAR_IQ_DESCR_CTX_INV | DMAR_IQ_DESCR_CTX_GLOB, 0);
251	dmar_qi_emit_wait_seq(unit, &gseq, true);
252	dmar_qi_advance_tail(unit);
253	dmar_qi_wait_for_seq(unit, &gseq, false);
254}
255
256void
257dmar_qi_invalidate_iotlb_glob_locked(struct dmar_unit *unit)
258{
259	struct dmar_qi_genseq gseq;
260
261	DMAR_ASSERT_LOCKED(unit);
262	dmar_qi_ensure(unit, 2);
263	dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV | DMAR_IQ_DESCR_IOTLB_GLOB |
264	    DMAR_IQ_DESCR_IOTLB_DW | DMAR_IQ_DESCR_IOTLB_DR, 0);
265	dmar_qi_emit_wait_seq(unit, &gseq, true);
266	dmar_qi_advance_tail(unit);
267	dmar_qi_wait_for_seq(unit, &gseq, false);
268}
269
270void
271dmar_qi_invalidate_iec_glob(struct dmar_unit *unit)
272{
273	struct dmar_qi_genseq gseq;
274
275	DMAR_ASSERT_LOCKED(unit);
276	dmar_qi_ensure(unit, 2);
277	dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV, 0);
278	dmar_qi_emit_wait_seq(unit, &gseq, true);
279	dmar_qi_advance_tail(unit);
280	dmar_qi_wait_for_seq(unit, &gseq, false);
281}
282
283void
284dmar_qi_invalidate_iec(struct dmar_unit *unit, u_int start, u_int cnt)
285{
286	struct dmar_qi_genseq gseq;
287	u_int c, l;
288
289	DMAR_ASSERT_LOCKED(unit);
290	KASSERT(start < unit->irte_cnt && start < start + cnt &&
291	    start + cnt <= unit->irte_cnt,
292	    ("inv iec overflow %d %d %d", unit->irte_cnt, start, cnt));
293	for (; cnt > 0; cnt -= c, start += c) {
294		l = ffs(start | cnt) - 1;
295		c = 1 << l;
296		dmar_qi_ensure(unit, 1);
297		dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV |
298		    DMAR_IQ_DESCR_IEC_IDX | DMAR_IQ_DESCR_IEC_IIDX(start) |
299		    DMAR_IQ_DESCR_IEC_IM(l), 0);
300	}
301	dmar_qi_ensure(unit, 1);
302	dmar_qi_emit_wait_seq(unit, &gseq, true);
303	dmar_qi_advance_tail(unit);
304
305	/*
306	 * The caller of the function, in particular,
307	 * dmar_ir_program_irte(), may be called from the context
308	 * where the sleeping is forbidden (in fact, the
309	 * intr_table_lock mutex may be held, locked from
310	 * intr_shuffle_irqs()).  Wait for the invalidation completion
311	 * using the busy wait.
312	 *
313	 * The impact on the interrupt input setup code is small, the
314	 * expected overhead is comparable with the chipset register
315	 * read.  It is more harmful for the parallel DMA operations,
316	 * since we own the dmar unit lock until whole invalidation
317	 * queue is processed, which includes requests possibly issued
318	 * before our request.
319	 */
320	dmar_qi_wait_for_seq(unit, &gseq, true);
321}
322
323int
324dmar_qi_intr(void *arg)
325{
326	struct dmar_unit *unit;
327
328	unit = arg;
329	KASSERT(unit->qi_enabled, ("dmar%d: QI is not enabled", unit->unit));
330	taskqueue_enqueue(unit->qi_taskqueue, &unit->qi_task);
331	return (FILTER_HANDLED);
332}
333
334static void
335dmar_qi_task(void *arg, int pending __unused)
336{
337	struct dmar_unit *unit;
338	struct dmar_map_entry *entry;
339	uint32_t ics;
340
341	unit = arg;
342
343	DMAR_LOCK(unit);
344	for (;;) {
345		entry = TAILQ_FIRST(&unit->tlb_flush_entries);
346		if (entry == NULL)
347			break;
348		if (!dmar_qi_seq_processed(unit, &entry->gseq))
349			break;
350		TAILQ_REMOVE(&unit->tlb_flush_entries, entry, dmamap_link);
351		DMAR_UNLOCK(unit);
352		dmar_domain_free_entry(entry, (entry->flags &
353		    DMAR_MAP_ENTRY_QI_NF) == 0);
354		DMAR_LOCK(unit);
355	}
356	ics = dmar_read4(unit, DMAR_ICS_REG);
357	if ((ics & DMAR_ICS_IWC) != 0) {
358		ics = DMAR_ICS_IWC;
359		dmar_write4(unit, DMAR_ICS_REG, ics);
360	}
361	if (unit->inv_seq_waiters > 0)
362		wakeup(&unit->inv_seq_waiters);
363	DMAR_UNLOCK(unit);
364}
365
366int
367dmar_init_qi(struct dmar_unit *unit)
368{
369	uint64_t iqa;
370	uint32_t ics;
371	int qi_sz;
372
373	if (!DMAR_HAS_QI(unit) || (unit->hw_cap & DMAR_CAP_CM) != 0)
374		return (0);
375	unit->qi_enabled = 1;
376	TUNABLE_INT_FETCH("hw.dmar.qi", &unit->qi_enabled);
377	if (!unit->qi_enabled)
378		return (0);
379
380	TAILQ_INIT(&unit->tlb_flush_entries);
381	TASK_INIT(&unit->qi_task, 0, dmar_qi_task, unit);
382	unit->qi_taskqueue = taskqueue_create_fast("dmarqf", M_WAITOK,
383	    taskqueue_thread_enqueue, &unit->qi_taskqueue);
384	taskqueue_start_threads(&unit->qi_taskqueue, 1, PI_AV,
385	    "dmar%d qi taskq", unit->unit);
386
387	unit->inv_waitd_gen = 0;
388	unit->inv_waitd_seq = 1;
389
390	qi_sz = DMAR_IQA_QS_DEF;
391	TUNABLE_INT_FETCH("hw.dmar.qi_size", &qi_sz);
392	if (qi_sz > DMAR_IQA_QS_MAX)
393		qi_sz = DMAR_IQA_QS_MAX;
394	unit->inv_queue_size = (1ULL << qi_sz) * PAGE_SIZE;
395	/* Reserve one descriptor to prevent wraparound. */
396	unit->inv_queue_avail = unit->inv_queue_size - DMAR_IQ_DESCR_SZ;
397
398	/* The invalidation queue reads by DMARs are always coherent. */
399	unit->inv_queue = kmem_alloc_contig(kernel_arena, unit->inv_queue_size,
400	    M_WAITOK | M_ZERO, 0, dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
401	unit->inv_waitd_seq_hw_phys = pmap_kextract(
402	    (vm_offset_t)&unit->inv_waitd_seq_hw);
403
404	DMAR_LOCK(unit);
405	dmar_write8(unit, DMAR_IQT_REG, 0);
406	iqa = pmap_kextract(unit->inv_queue);
407	iqa |= qi_sz;
408	dmar_write8(unit, DMAR_IQA_REG, iqa);
409	dmar_enable_qi(unit);
410	ics = dmar_read4(unit, DMAR_ICS_REG);
411	if ((ics & DMAR_ICS_IWC) != 0) {
412		ics = DMAR_ICS_IWC;
413		dmar_write4(unit, DMAR_ICS_REG, ics);
414	}
415	dmar_enable_qi_intr(unit);
416	DMAR_UNLOCK(unit);
417
418	return (0);
419}
420
421void
422dmar_fini_qi(struct dmar_unit *unit)
423{
424	struct dmar_qi_genseq gseq;
425
426	if (unit->qi_enabled)
427		return;
428	taskqueue_drain(unit->qi_taskqueue, &unit->qi_task);
429	taskqueue_free(unit->qi_taskqueue);
430	unit->qi_taskqueue = NULL;
431
432	DMAR_LOCK(unit);
433	/* quisce */
434	dmar_qi_ensure(unit, 1);
435	dmar_qi_emit_wait_seq(unit, &gseq, true);
436	dmar_qi_advance_tail(unit);
437	dmar_qi_wait_for_seq(unit, &gseq, false);
438	/* only after the quisce, disable queue */
439	dmar_disable_qi_intr(unit);
440	dmar_disable_qi(unit);
441	KASSERT(unit->inv_seq_waiters == 0,
442	    ("dmar%d: waiters on disabled queue", unit->unit));
443	DMAR_UNLOCK(unit);
444
445	kmem_free(kernel_arena, unit->inv_queue, unit->inv_queue_size);
446	unit->inv_queue = 0;
447	unit->inv_queue_size = 0;
448	unit->qi_enabled = 0;
449}
450
451void
452dmar_enable_qi_intr(struct dmar_unit *unit)
453{
454	uint32_t iectl;
455
456	DMAR_ASSERT_LOCKED(unit);
457	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
458	iectl = dmar_read4(unit, DMAR_IECTL_REG);
459	iectl &= ~DMAR_IECTL_IM;
460	dmar_write4(unit, DMAR_IECTL_REG, iectl);
461}
462
463void
464dmar_disable_qi_intr(struct dmar_unit *unit)
465{
466	uint32_t iectl;
467
468	DMAR_ASSERT_LOCKED(unit);
469	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
470	iectl = dmar_read4(unit, DMAR_IECTL_REG);
471	dmar_write4(unit, DMAR_IECTL_REG, iectl | DMAR_IECTL_IM);
472}
473