xref: /freebsd/sys/x86/iommu/intel_qi.c (revision 5ffd83dbcc34f10e07f6d3e968ae6365869615f4)
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 <vm/vm.h>
49 #include <vm/vm_extern.h>
50 #include <vm/vm_kern.h>
51 #include <vm/vm_page.h>
52 #include <vm/vm_map.h>
53 #include <contrib/dev/acpica/include/acpi.h>
54 #include <contrib/dev/acpica/include/accommon.h>
55 #include <dev/acpica/acpivar.h>
56 #include <dev/pci/pcireg.h>
57 #include <machine/bus.h>
58 #include <machine/cpu.h>
59 #include <x86/include/busdma_impl.h>
60 #include <dev/iommu/busdma_iommu.h>
61 #include <x86/iommu/intel_reg.h>
62 #include <x86/iommu/intel_dmar.h>
63 
64 static bool
65 dmar_qi_seq_processed(const struct dmar_unit *unit,
66     const struct iommu_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 
74 static int
75 dmar_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 
87 static int
88 dmar_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 
100 static void
101 dmar_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 
108 static void
109 dmar_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 
143 static void
144 dmar_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 
162 static void
163 dmar_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 
176 static void
177 dmar_qi_emit_wait_seq(struct dmar_unit *unit, struct iommu_qi_genseq *pseq,
178     bool emit_wait)
179 {
180 	struct iommu_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 
205 static void
206 dmar_qi_wait_for_seq(struct dmar_unit *unit, const struct iommu_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->iommu.lock, 0,
217 			    "dmarse", hz);
218 		}
219 	}
220 	unit->inv_seq_waiters--;
221 }
222 
223 void
224 dmar_qi_invalidate_locked(struct dmar_domain *domain, iommu_gaddr_t base,
225     iommu_gaddr_t size, struct iommu_qi_genseq *pseq, bool emit_wait)
226 {
227 	struct dmar_unit *unit;
228 	iommu_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 
246 void
247 dmar_qi_invalidate_ctx_glob_locked(struct dmar_unit *unit)
248 {
249 	struct iommu_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 
259 void
260 dmar_qi_invalidate_iotlb_glob_locked(struct dmar_unit *unit)
261 {
262 	struct iommu_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 
273 void
274 dmar_qi_invalidate_iec_glob(struct dmar_unit *unit)
275 {
276 	struct iommu_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 
286 void
287 dmar_qi_invalidate_iec(struct dmar_unit *unit, u_int start, u_int cnt)
288 {
289 	struct iommu_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 
326 int
327 dmar_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",
333 	    unit->iommu.unit));
334 	taskqueue_enqueue(unit->qi_taskqueue, &unit->qi_task);
335 	return (FILTER_HANDLED);
336 }
337 
338 static void
339 dmar_qi_task(void *arg, int pending __unused)
340 {
341 	struct dmar_unit *unit;
342 	struct iommu_map_entry *entry;
343 	uint32_t ics;
344 
345 	unit = arg;
346 
347 	DMAR_LOCK(unit);
348 	for (;;) {
349 		entry = TAILQ_FIRST(&unit->tlb_flush_entries);
350 		if (entry == NULL)
351 			break;
352 		if (!dmar_qi_seq_processed(unit, &entry->gseq))
353 			break;
354 		TAILQ_REMOVE(&unit->tlb_flush_entries, entry, dmamap_link);
355 		DMAR_UNLOCK(unit);
356 		dmar_domain_free_entry(entry, (entry->flags &
357 		    IOMMU_MAP_ENTRY_QI_NF) == 0);
358 		DMAR_LOCK(unit);
359 	}
360 	ics = dmar_read4(unit, DMAR_ICS_REG);
361 	if ((ics & DMAR_ICS_IWC) != 0) {
362 		ics = DMAR_ICS_IWC;
363 		dmar_write4(unit, DMAR_ICS_REG, ics);
364 	}
365 	if (unit->inv_seq_waiters > 0)
366 		wakeup(&unit->inv_seq_waiters);
367 	DMAR_UNLOCK(unit);
368 }
369 
370 int
371 dmar_init_qi(struct dmar_unit *unit)
372 {
373 	uint64_t iqa;
374 	uint32_t ics;
375 	int qi_sz;
376 
377 	if (!DMAR_HAS_QI(unit) || (unit->hw_cap & DMAR_CAP_CM) != 0)
378 		return (0);
379 	unit->qi_enabled = 1;
380 	TUNABLE_INT_FETCH("hw.dmar.qi", &unit->qi_enabled);
381 	if (!unit->qi_enabled)
382 		return (0);
383 
384 	TAILQ_INIT(&unit->tlb_flush_entries);
385 	TASK_INIT(&unit->qi_task, 0, dmar_qi_task, unit);
386 	unit->qi_taskqueue = taskqueue_create_fast("dmarqf", M_WAITOK,
387 	    taskqueue_thread_enqueue, &unit->qi_taskqueue);
388 	taskqueue_start_threads(&unit->qi_taskqueue, 1, PI_AV,
389 	    "dmar%d qi taskq", unit->iommu.unit);
390 
391 	unit->inv_waitd_gen = 0;
392 	unit->inv_waitd_seq = 1;
393 
394 	qi_sz = DMAR_IQA_QS_DEF;
395 	TUNABLE_INT_FETCH("hw.dmar.qi_size", &qi_sz);
396 	if (qi_sz > DMAR_IQA_QS_MAX)
397 		qi_sz = DMAR_IQA_QS_MAX;
398 	unit->inv_queue_size = (1ULL << qi_sz) * PAGE_SIZE;
399 	/* Reserve one descriptor to prevent wraparound. */
400 	unit->inv_queue_avail = unit->inv_queue_size - DMAR_IQ_DESCR_SZ;
401 
402 	/* The invalidation queue reads by DMARs are always coherent. */
403 	unit->inv_queue = kmem_alloc_contig(unit->inv_queue_size, M_WAITOK |
404 	    M_ZERO, 0, dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
405 	unit->inv_waitd_seq_hw_phys = pmap_kextract(
406 	    (vm_offset_t)&unit->inv_waitd_seq_hw);
407 
408 	DMAR_LOCK(unit);
409 	dmar_write8(unit, DMAR_IQT_REG, 0);
410 	iqa = pmap_kextract(unit->inv_queue);
411 	iqa |= qi_sz;
412 	dmar_write8(unit, DMAR_IQA_REG, iqa);
413 	dmar_enable_qi(unit);
414 	ics = dmar_read4(unit, DMAR_ICS_REG);
415 	if ((ics & DMAR_ICS_IWC) != 0) {
416 		ics = DMAR_ICS_IWC;
417 		dmar_write4(unit, DMAR_ICS_REG, ics);
418 	}
419 	dmar_enable_qi_intr(unit);
420 	DMAR_UNLOCK(unit);
421 
422 	return (0);
423 }
424 
425 void
426 dmar_fini_qi(struct dmar_unit *unit)
427 {
428 	struct iommu_qi_genseq gseq;
429 
430 	if (!unit->qi_enabled)
431 		return;
432 	taskqueue_drain(unit->qi_taskqueue, &unit->qi_task);
433 	taskqueue_free(unit->qi_taskqueue);
434 	unit->qi_taskqueue = NULL;
435 
436 	DMAR_LOCK(unit);
437 	/* quisce */
438 	dmar_qi_ensure(unit, 1);
439 	dmar_qi_emit_wait_seq(unit, &gseq, true);
440 	dmar_qi_advance_tail(unit);
441 	dmar_qi_wait_for_seq(unit, &gseq, false);
442 	/* only after the quisce, disable queue */
443 	dmar_disable_qi_intr(unit);
444 	dmar_disable_qi(unit);
445 	KASSERT(unit->inv_seq_waiters == 0,
446 	    ("dmar%d: waiters on disabled queue", unit->iommu.unit));
447 	DMAR_UNLOCK(unit);
448 
449 	kmem_free(unit->inv_queue, unit->inv_queue_size);
450 	unit->inv_queue = 0;
451 	unit->inv_queue_size = 0;
452 	unit->qi_enabled = 0;
453 }
454 
455 void
456 dmar_enable_qi_intr(struct dmar_unit *unit)
457 {
458 	uint32_t iectl;
459 
460 	DMAR_ASSERT_LOCKED(unit);
461 	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported",
462 	    unit->iommu.unit));
463 	iectl = dmar_read4(unit, DMAR_IECTL_REG);
464 	iectl &= ~DMAR_IECTL_IM;
465 	dmar_write4(unit, DMAR_IECTL_REG, iectl);
466 }
467 
468 void
469 dmar_disable_qi_intr(struct dmar_unit *unit)
470 {
471 	uint32_t iectl;
472 
473 	DMAR_ASSERT_LOCKED(unit);
474 	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported",
475 	    unit->iommu.unit));
476 	iectl = dmar_read4(unit, DMAR_IECTL_REG);
477 	dmar_write4(unit, DMAR_IECTL_REG, iectl | DMAR_IECTL_IM);
478 }
479