xref: /freebsd/sys/x86/iommu/intel_qi.c (revision ec65e4f8d0654361df5e97d4de3518edebf76b46)
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("$FreeBSD$");
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/tree.h>
44 #include <sys/vmem.h>
45 #include <machine/bus.h>
46 #include <contrib/dev/acpica/include/acpi.h>
47 #include <contrib/dev/acpica/include/accommon.h>
48 #include <dev/acpica/acpivar.h>
49 #include <vm/vm.h>
50 #include <vm/vm_extern.h>
51 #include <vm/vm_kern.h>
52 #include <vm/vm_page.h>
53 #include <vm/vm_map.h>
54 #include <machine/cpu.h>
55 #include <x86/include/busdma_impl.h>
56 #include <x86/iommu/intel_reg.h>
57 #include <x86/iommu/busdma_dmar.h>
58 #include <x86/iommu/intel_dmar.h>
59 
60 static bool
61 dmar_qi_seq_processed(const struct dmar_unit *unit,
62     const struct dmar_qi_genseq *pseq)
63 {
64 
65 	return (pseq->gen < unit->inv_waitd_gen ||
66 	    (pseq->gen == unit->inv_waitd_gen &&
67 	     pseq->seq <= unit->inv_waitd_seq_hw));
68 }
69 
70 static int
71 dmar_enable_qi(struct dmar_unit *unit)
72 {
73 
74 	DMAR_ASSERT_LOCKED(unit);
75 	unit->hw_gcmd |= DMAR_GCMD_QIE;
76 	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
77 	/* XXXKIB should have a timeout */
78 	while ((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES) == 0)
79 		cpu_spinwait();
80 	return (0);
81 }
82 
83 static int
84 dmar_disable_qi(struct dmar_unit *unit)
85 {
86 
87 	DMAR_ASSERT_LOCKED(unit);
88 	unit->hw_gcmd &= ~DMAR_GCMD_QIE;
89 	dmar_write4(unit, DMAR_GCMD_REG, unit->hw_gcmd);
90 	/* XXXKIB should have a timeout */
91 	while ((dmar_read4(unit, DMAR_GSTS_REG) & DMAR_GSTS_QIES) != 0)
92 		cpu_spinwait();
93 	return (0);
94 }
95 
96 static void
97 dmar_qi_advance_tail(struct dmar_unit *unit)
98 {
99 
100 	DMAR_ASSERT_LOCKED(unit);
101 	dmar_write4(unit, DMAR_IQT_REG, unit->inv_queue_tail);
102 }
103 
104 static void
105 dmar_qi_ensure(struct dmar_unit *unit, int descr_count)
106 {
107 	uint32_t head;
108 	int bytes;
109 
110 	DMAR_ASSERT_LOCKED(unit);
111 	bytes = descr_count << DMAR_IQ_DESCR_SZ_SHIFT;
112 	for (;;) {
113 		if (bytes <= unit->inv_queue_avail)
114 			break;
115 		/* refill */
116 		head = dmar_read4(unit, DMAR_IQH_REG);
117 		head &= DMAR_IQH_MASK;
118 		unit->inv_queue_avail = head - unit->inv_queue_tail -
119 		    DMAR_IQ_DESCR_SZ;
120 		if (head <= unit->inv_queue_tail)
121 			unit->inv_queue_avail += unit->inv_queue_size;
122 		if (bytes <= unit->inv_queue_avail)
123 			break;
124 
125 		/*
126 		 * No space in the queue, do busy wait.  Hardware must
127 		 * make a progress.  But first advance the tail to
128 		 * inform the descriptor streamer about entries we
129 		 * might have already filled, otherwise they could
130 		 * clog the whole queue..
131 		 */
132 		dmar_qi_advance_tail(unit);
133 		unit->inv_queue_full++;
134 		cpu_spinwait();
135 	}
136 	unit->inv_queue_avail -= bytes;
137 }
138 
139 static void
140 dmar_qi_emit(struct dmar_unit *unit, uint64_t data1, uint64_t data2)
141 {
142 
143 	DMAR_ASSERT_LOCKED(unit);
144 	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data1;
145 	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
146 	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
147 	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
148 	    (uintmax_t)unit->inv_queue_size));
149 	unit->inv_queue_tail &= unit->inv_queue_size - 1;
150 	*(volatile uint64_t *)(unit->inv_queue + unit->inv_queue_tail) = data2;
151 	unit->inv_queue_tail += DMAR_IQ_DESCR_SZ / 2;
152 	KASSERT(unit->inv_queue_tail <= unit->inv_queue_size,
153 	    ("tail overflow 0x%x 0x%jx", unit->inv_queue_tail,
154 	    (uintmax_t)unit->inv_queue_size));
155 	unit->inv_queue_tail &= unit->inv_queue_size - 1;
156 }
157 
158 static void
159 dmar_qi_emit_wait_descr(struct dmar_unit *unit, uint32_t seq, bool intr,
160     bool memw, bool fence)
161 {
162 
163 	DMAR_ASSERT_LOCKED(unit);
164 	dmar_qi_emit(unit, DMAR_IQ_DESCR_WAIT_ID |
165 	    (intr ? DMAR_IQ_DESCR_WAIT_IF : 0) |
166 	    (memw ? DMAR_IQ_DESCR_WAIT_SW : 0) |
167 	    (fence ? DMAR_IQ_DESCR_WAIT_FN : 0) |
168 	    (memw ? DMAR_IQ_DESCR_WAIT_SD(seq) : 0),
169 	    memw ? unit->inv_waitd_seq_hw_phys : 0);
170 }
171 
172 static void
173 dmar_qi_emit_wait_seq(struct dmar_unit *unit, struct dmar_qi_genseq *pseq)
174 {
175 	struct dmar_qi_genseq gsec;
176 	uint32_t seq;
177 
178 	KASSERT(pseq != NULL, ("wait descriptor with no place for seq"));
179 	DMAR_ASSERT_LOCKED(unit);
180 	if (unit->inv_waitd_seq == 0xffffffff) {
181 		gsec.gen = unit->inv_waitd_gen;
182 		gsec.seq = unit->inv_waitd_seq;
183 		dmar_qi_ensure(unit, 1);
184 		dmar_qi_emit_wait_descr(unit, gsec.seq, false, true, false);
185 		dmar_qi_advance_tail(unit);
186 		while (!dmar_qi_seq_processed(unit, &gsec))
187 			cpu_spinwait();
188 		unit->inv_waitd_gen++;
189 		unit->inv_waitd_seq = 1;
190 	}
191 	seq = unit->inv_waitd_seq++;
192 	pseq->gen = unit->inv_waitd_gen;
193 	pseq->seq = seq;
194 	dmar_qi_emit_wait_descr(unit, seq, true, true, false);
195 }
196 
197 static void
198 dmar_qi_wait_for_seq(struct dmar_unit *unit, const struct dmar_qi_genseq *gseq,
199     bool nowait)
200 {
201 
202 	DMAR_ASSERT_LOCKED(unit);
203 	unit->inv_seq_waiters++;
204 	while (!dmar_qi_seq_processed(unit, gseq)) {
205 		if (cold || nowait) {
206 			cpu_spinwait();
207 		} else {
208 			msleep(&unit->inv_seq_waiters, &unit->lock, 0,
209 			    "dmarse", hz);
210 		}
211 	}
212 	unit->inv_seq_waiters--;
213 }
214 
215 void
216 dmar_qi_invalidate_locked(struct dmar_domain *domain, dmar_gaddr_t base,
217     dmar_gaddr_t size, struct dmar_qi_genseq *pseq)
218 {
219 	struct dmar_unit *unit;
220 	dmar_gaddr_t isize;
221 	int am;
222 
223 	unit = domain->dmar;
224 	DMAR_ASSERT_LOCKED(unit);
225 	for (; size > 0; base += isize, size -= isize) {
226 		am = calc_am(unit, base, size, &isize);
227 		dmar_qi_ensure(unit, 1);
228 		dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV |
229 		    DMAR_IQ_DESCR_IOTLB_PAGE | DMAR_IQ_DESCR_IOTLB_DW |
230 		    DMAR_IQ_DESCR_IOTLB_DR |
231 		    DMAR_IQ_DESCR_IOTLB_DID(domain->domain),
232 		    base | am);
233 	}
234 	if (pseq != NULL) {
235 		dmar_qi_ensure(unit, 1);
236 		dmar_qi_emit_wait_seq(unit, pseq);
237 	}
238 	dmar_qi_advance_tail(unit);
239 }
240 
241 void
242 dmar_qi_invalidate_ctx_glob_locked(struct dmar_unit *unit)
243 {
244 	struct dmar_qi_genseq gseq;
245 
246 	DMAR_ASSERT_LOCKED(unit);
247 	dmar_qi_ensure(unit, 2);
248 	dmar_qi_emit(unit, DMAR_IQ_DESCR_CTX_INV | DMAR_IQ_DESCR_CTX_GLOB, 0);
249 	dmar_qi_emit_wait_seq(unit, &gseq);
250 	dmar_qi_advance_tail(unit);
251 	dmar_qi_wait_for_seq(unit, &gseq, false);
252 }
253 
254 void
255 dmar_qi_invalidate_iotlb_glob_locked(struct dmar_unit *unit)
256 {
257 	struct dmar_qi_genseq gseq;
258 
259 	DMAR_ASSERT_LOCKED(unit);
260 	dmar_qi_ensure(unit, 2);
261 	dmar_qi_emit(unit, DMAR_IQ_DESCR_IOTLB_INV | DMAR_IQ_DESCR_IOTLB_GLOB |
262 	    DMAR_IQ_DESCR_IOTLB_DW | DMAR_IQ_DESCR_IOTLB_DR, 0);
263 	dmar_qi_emit_wait_seq(unit, &gseq);
264 	dmar_qi_advance_tail(unit);
265 	dmar_qi_wait_for_seq(unit, &gseq, false);
266 }
267 
268 void
269 dmar_qi_invalidate_iec_glob(struct dmar_unit *unit)
270 {
271 	struct dmar_qi_genseq gseq;
272 
273 	DMAR_ASSERT_LOCKED(unit);
274 	dmar_qi_ensure(unit, 2);
275 	dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV, 0);
276 	dmar_qi_emit_wait_seq(unit, &gseq);
277 	dmar_qi_advance_tail(unit);
278 	dmar_qi_wait_for_seq(unit, &gseq, false);
279 }
280 
281 void
282 dmar_qi_invalidate_iec(struct dmar_unit *unit, u_int start, u_int cnt)
283 {
284 	struct dmar_qi_genseq gseq;
285 	u_int c, l;
286 
287 	DMAR_ASSERT_LOCKED(unit);
288 	KASSERT(start < unit->irte_cnt && start < start + cnt &&
289 	    start + cnt <= unit->irte_cnt,
290 	    ("inv iec overflow %d %d %d", unit->irte_cnt, start, cnt));
291 	for (; cnt > 0; cnt -= c, start += c) {
292 		l = ffs(start | cnt) - 1;
293 		c = 1 << l;
294 		dmar_qi_ensure(unit, 1);
295 		dmar_qi_emit(unit, DMAR_IQ_DESCR_IEC_INV |
296 		    DMAR_IQ_DESCR_IEC_IDX | DMAR_IQ_DESCR_IEC_IIDX(start) |
297 		    DMAR_IQ_DESCR_IEC_IM(l), 0);
298 	}
299 	dmar_qi_ensure(unit, 1);
300 	dmar_qi_emit_wait_seq(unit, &gseq);
301 	dmar_qi_advance_tail(unit);
302 
303 	/*
304 	 * The caller of the function, in particular,
305 	 * dmar_ir_program_irte(), may be called from the context
306 	 * where the sleeping is forbidden (in fact, the
307 	 * intr_table_lock mutex may be held, locked from
308 	 * intr_shuffle_irqs()).  Wait for the invalidation completion
309 	 * using the busy wait.
310 	 *
311 	 * The impact on the interrupt input setup code is small, the
312 	 * expected overhead is comparable with the chipset register
313 	 * read.  It is more harmful for the parallel DMA operations,
314 	 * since we own the dmar unit lock until whole invalidation
315 	 * queue is processed, which includes requests possibly issued
316 	 * before our request.
317 	 */
318 	dmar_qi_wait_for_seq(unit, &gseq, true);
319 }
320 
321 int
322 dmar_qi_intr(void *arg)
323 {
324 	struct dmar_unit *unit;
325 
326 	unit = arg;
327 	KASSERT(unit->qi_enabled, ("dmar%d: QI is not enabled", unit->unit));
328 	taskqueue_enqueue(unit->qi_taskqueue, &unit->qi_task);
329 	return (FILTER_HANDLED);
330 }
331 
332 static void
333 dmar_qi_task(void *arg, int pending __unused)
334 {
335 	struct dmar_unit *unit;
336 	struct dmar_map_entry *entry;
337 	uint32_t ics;
338 
339 	unit = arg;
340 
341 	DMAR_LOCK(unit);
342 	for (;;) {
343 		entry = TAILQ_FIRST(&unit->tlb_flush_entries);
344 		if (entry == NULL)
345 			break;
346 		if ((entry->gseq.gen == 0 && entry->gseq.seq == 0) ||
347 		    !dmar_qi_seq_processed(unit, &entry->gseq))
348 			break;
349 		TAILQ_REMOVE(&unit->tlb_flush_entries, entry, dmamap_link);
350 		DMAR_UNLOCK(unit);
351 		dmar_domain_free_entry(entry, (entry->flags &
352 		    DMAR_MAP_ENTRY_QI_NF) == 0);
353 		DMAR_LOCK(unit);
354 	}
355 	ics = dmar_read4(unit, DMAR_ICS_REG);
356 	if ((ics & DMAR_ICS_IWC) != 0) {
357 		ics = DMAR_ICS_IWC;
358 		dmar_write4(unit, DMAR_ICS_REG, ics);
359 	}
360 	if (unit->inv_seq_waiters > 0)
361 		wakeup(&unit->inv_seq_waiters);
362 	DMAR_UNLOCK(unit);
363 }
364 
365 int
366 dmar_init_qi(struct dmar_unit *unit)
367 {
368 	uint64_t iqa;
369 	uint32_t ics;
370 	int qi_sz;
371 
372 	if (!DMAR_HAS_QI(unit) || (unit->hw_cap & DMAR_CAP_CM) != 0)
373 		return (0);
374 	unit->qi_enabled = 1;
375 	TUNABLE_INT_FETCH("hw.dmar.qi", &unit->qi_enabled);
376 	if (!unit->qi_enabled)
377 		return (0);
378 
379 	TAILQ_INIT(&unit->tlb_flush_entries);
380 	TASK_INIT(&unit->qi_task, 0, dmar_qi_task, unit);
381 	unit->qi_taskqueue = taskqueue_create_fast("dmar", M_WAITOK,
382 	    taskqueue_thread_enqueue, &unit->qi_taskqueue);
383 	taskqueue_start_threads(&unit->qi_taskqueue, 1, PI_AV,
384 	    "dmar%d qi taskq", unit->unit);
385 
386 	unit->inv_waitd_gen = 0;
387 	unit->inv_waitd_seq = 1;
388 
389 	qi_sz = DMAR_IQA_QS_DEF;
390 	TUNABLE_INT_FETCH("hw.dmar.qi_size", &qi_sz);
391 	if (qi_sz > DMAR_IQA_QS_MAX)
392 		qi_sz = DMAR_IQA_QS_MAX;
393 	unit->inv_queue_size = (1ULL << qi_sz) * PAGE_SIZE;
394 	/* Reserve one descriptor to prevent wraparound. */
395 	unit->inv_queue_avail = unit->inv_queue_size - DMAR_IQ_DESCR_SZ;
396 
397 	/* The invalidation queue reads by DMARs are always coherent. */
398 	unit->inv_queue = kmem_alloc_contig(kernel_arena, unit->inv_queue_size,
399 	    M_WAITOK | M_ZERO, 0, dmar_high, PAGE_SIZE, 0, VM_MEMATTR_DEFAULT);
400 	unit->inv_waitd_seq_hw_phys = pmap_kextract(
401 	    (vm_offset_t)&unit->inv_waitd_seq_hw);
402 
403 	DMAR_LOCK(unit);
404 	dmar_write8(unit, DMAR_IQT_REG, 0);
405 	iqa = pmap_kextract(unit->inv_queue);
406 	iqa |= qi_sz;
407 	dmar_write8(unit, DMAR_IQA_REG, iqa);
408 	dmar_enable_qi(unit);
409 	ics = dmar_read4(unit, DMAR_ICS_REG);
410 	if ((ics & DMAR_ICS_IWC) != 0) {
411 		ics = DMAR_ICS_IWC;
412 		dmar_write4(unit, DMAR_ICS_REG, ics);
413 	}
414 	dmar_enable_qi_intr(unit);
415 	DMAR_UNLOCK(unit);
416 
417 	return (0);
418 }
419 
420 void
421 dmar_fini_qi(struct dmar_unit *unit)
422 {
423 	struct dmar_qi_genseq gseq;
424 
425 	if (unit->qi_enabled)
426 		return;
427 	taskqueue_drain(unit->qi_taskqueue, &unit->qi_task);
428 	taskqueue_free(unit->qi_taskqueue);
429 	unit->qi_taskqueue = NULL;
430 
431 	DMAR_LOCK(unit);
432 	/* quisce */
433 	dmar_qi_ensure(unit, 1);
434 	dmar_qi_emit_wait_seq(unit, &gseq);
435 	dmar_qi_advance_tail(unit);
436 	dmar_qi_wait_for_seq(unit, &gseq, false);
437 	/* only after the quisce, disable queue */
438 	dmar_disable_qi_intr(unit);
439 	dmar_disable_qi(unit);
440 	KASSERT(unit->inv_seq_waiters == 0,
441 	    ("dmar%d: waiters on disabled queue", unit->unit));
442 	DMAR_UNLOCK(unit);
443 
444 	kmem_free(kernel_arena, unit->inv_queue, unit->inv_queue_size);
445 	unit->inv_queue = 0;
446 	unit->inv_queue_size = 0;
447 	unit->qi_enabled = 0;
448 }
449 
450 void
451 dmar_enable_qi_intr(struct dmar_unit *unit)
452 {
453 	uint32_t iectl;
454 
455 	DMAR_ASSERT_LOCKED(unit);
456 	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
457 	iectl = dmar_read4(unit, DMAR_IECTL_REG);
458 	iectl &= ~DMAR_IECTL_IM;
459 	dmar_write4(unit, DMAR_IECTL_REG, iectl);
460 }
461 
462 void
463 dmar_disable_qi_intr(struct dmar_unit *unit)
464 {
465 	uint32_t iectl;
466 
467 	DMAR_ASSERT_LOCKED(unit);
468 	KASSERT(DMAR_HAS_QI(unit), ("dmar%d: QI is not supported", unit->unit));
469 	iectl = dmar_read4(unit, DMAR_IECTL_REG);
470 	dmar_write4(unit, DMAR_IECTL_REG, iectl | DMAR_IECTL_IM);
471 }
472