xref: /freebsd/sys/x86/x86/msi.c (revision cb38499303621553c977fd7dd7f18d12731fcd9c)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2006 Yahoo!, Inc.
5  * All rights reserved.
6  * Written by: John Baldwin <jhb@FreeBSD.org>
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  * 3. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 /*
34  * Support for PCI Message Signalled Interrupts (MSI).  MSI interrupts on
35  * x86 are basically APIC messages that the northbridge delivers directly
36  * to the local APICs as if they had come from an I/O APIC.
37  */
38 
39 #include <sys/cdefs.h>
40 #include "opt_acpi.h"
41 #include "opt_iommu.h"
42 
43 #include <sys/param.h>
44 #include <sys/bus.h>
45 #include <sys/kernel.h>
46 #include <sys/limits.h>
47 #include <sys/lock.h>
48 #include <sys/malloc.h>
49 #include <sys/mutex.h>
50 #include <sys/sx.h>
51 #include <sys/sysctl.h>
52 #include <sys/systm.h>
53 #include <x86/apicreg.h>
54 #include <machine/cputypes.h>
55 #include <machine/md_var.h>
56 #include <machine/frame.h>
57 #include <machine/intr_machdep.h>
58 #include <x86/apicvar.h>
59 #include <x86/iommu/iommu_intrmap.h>
60 #include <machine/specialreg.h>
61 #include <dev/pci/pcivar.h>
62 
63 /* Fields in address for Intel MSI messages. */
64 #define	MSI_INTEL_ADDR_DEST		0x000ff000
65 #define	MSI_INTEL_ADDR_RH		0x00000008
66 # define MSI_INTEL_ADDR_RH_ON		0x00000008
67 # define MSI_INTEL_ADDR_RH_OFF		0x00000000
68 #define	MSI_INTEL_ADDR_DM		0x00000004
69 # define MSI_INTEL_ADDR_DM_PHYSICAL	0x00000000
70 # define MSI_INTEL_ADDR_DM_LOGICAL	0x00000004
71 
72 /* Fields in data for Intel MSI messages. */
73 #define	MSI_INTEL_DATA_TRGRMOD		IOART_TRGRMOD	/* Trigger mode. */
74 # define MSI_INTEL_DATA_TRGREDG		IOART_TRGREDG
75 # define MSI_INTEL_DATA_TRGRLVL		IOART_TRGRLVL
76 #define	MSI_INTEL_DATA_LEVEL		0x00004000	/* Polarity. */
77 # define MSI_INTEL_DATA_DEASSERT	0x00000000
78 # define MSI_INTEL_DATA_ASSERT		0x00004000
79 #define	MSI_INTEL_DATA_DELMOD		IOART_DELMOD	/* Delivery mode. */
80 # define MSI_INTEL_DATA_DELFIXED	IOART_DELFIXED
81 # define MSI_INTEL_DATA_DELLOPRI	IOART_DELLOPRI
82 # define MSI_INTEL_DATA_DELSMI		IOART_DELSMI
83 # define MSI_INTEL_DATA_DELNMI		IOART_DELNMI
84 # define MSI_INTEL_DATA_DELINIT		IOART_DELINIT
85 # define MSI_INTEL_DATA_DELEXINT	IOART_DELEXINT
86 #define	MSI_INTEL_DATA_INTVEC		IOART_INTVEC	/* Interrupt vector. */
87 
88 /*
89  * Build Intel MSI message and data values from a source.  AMD64 systems
90  * seem to be compatible, so we use the same function for both.
91  */
92 #define	INTEL_ADDR(msi)							\
93 	(MSI_INTEL_ADDR_BASE | (msi)->msi_cpu << 12 |			\
94 	    MSI_INTEL_ADDR_RH_OFF | MSI_INTEL_ADDR_DM_PHYSICAL)
95 #define	INTEL_DATA(msi)							\
96 	(MSI_INTEL_DATA_TRGREDG | MSI_INTEL_DATA_DELFIXED | (msi)->msi_vector)
97 
98 static MALLOC_DEFINE(M_MSI, "msi", "PCI MSI");
99 
100 /*
101  * MSI sources are bunched into groups.  This is because MSI forces
102  * all of the messages to share the address and data registers and
103  * thus certain properties (such as the local APIC ID target on x86).
104  * Each group has a 'first' source that contains information global to
105  * the group.  These fields are marked with (g) below.
106  *
107  * Note that local APIC ID is kind of special.  Each message will be
108  * assigned an ID by the system; however, a group will use the ID from
109  * the first message.
110  *
111  * For MSI-X, each message is isolated.
112  */
113 struct msi_intsrc {
114 	struct intsrc msi_intsrc;
115 	device_t msi_dev;		/* Owning device. (g) */
116 	struct msi_intsrc *msi_first;	/* First source in group. */
117 	u_int *msi_irqs;		/* Group's IRQ list. (g) */
118 	u_int msi_irq;			/* IRQ cookie. */
119 	u_int msi_cpu;			/* Local APIC ID. (g) */
120 	u_int msi_remap_cookie;		/* IOMMU cookie. */
121 	u_int msi_vector:8;		/* IDT vector. */
122 	u_int msi_count:8;		/* Messages in this group. (g) */
123 	u_int msi_maxcount:8;		/* Alignment for this group. (g) */
124 	u_int msi_enabled:8;		/* Enabled messages in this group. (g) */
125 	bool msi_msix;			/* MSI-X message. */
126 };
127 
128 static void	msi_create_source(void);
129 static void	msi_enable_source(struct intsrc *isrc);
130 static void	msi_disable_source(struct intsrc *isrc, int eoi);
131 static void	msi_eoi_source(struct intsrc *isrc);
132 static void	msi_enable_intr(struct intsrc *isrc);
133 static void	msi_disable_intr(struct intsrc *isrc);
134 static int	msi_vector(struct intsrc *isrc);
135 static int	msi_source_pending(struct intsrc *isrc);
136 static int	msi_config_intr(struct intsrc *isrc, enum intr_trigger trig,
137 		    enum intr_polarity pol);
138 static int	msi_assign_cpu(struct intsrc *isrc, u_int apic_id);
139 
140 struct pic msi_pic = {
141 	.pic_enable_source = msi_enable_source,
142 	.pic_disable_source = msi_disable_source,
143 	.pic_eoi_source = msi_eoi_source,
144 	.pic_enable_intr = msi_enable_intr,
145 	.pic_disable_intr = msi_disable_intr,
146 	.pic_vector = msi_vector,
147 	.pic_source_pending = msi_source_pending,
148 	.pic_suspend = NULL,
149 	.pic_resume = NULL,
150 	.pic_config_intr = msi_config_intr,
151 	.pic_assign_cpu = msi_assign_cpu,
152 	.pic_reprogram_pin = NULL,
153 };
154 
155 u_int first_msi_irq;
156 SYSCTL_UINT(_machdep, OID_AUTO, first_msi_irq, CTLFLAG_RD, &first_msi_irq, 0,
157     "Number of first IRQ reserved for MSI and MSI-X interrupts");
158 
159 u_int num_msi_irqs = 2048;
160 SYSCTL_UINT(_machdep, OID_AUTO, num_msi_irqs, CTLFLAG_RDTUN, &num_msi_irqs, 0,
161     "Number of IRQs reserved for MSI and MSI-X interrupts");
162 
163 #ifdef SMP
164 /**
165  * Xen hypervisors prior to 4.6.0 do not properly handle updates to
166  * enabled MSI-X table entries.  Allow migration of MSI-X interrupts
167  * to be disabled via a tunable. Values have the following meaning:
168  *
169  * -1: automatic detection by FreeBSD
170  *  0: enable migration
171  *  1: disable migration
172  */
173 int msix_disable_migration = -1;
174 SYSCTL_INT(_machdep, OID_AUTO, disable_msix_migration, CTLFLAG_RDTUN,
175     &msix_disable_migration, 0,
176     "Disable migration of MSI-X interrupts between CPUs");
177 #endif
178 
179 static int msi_enabled;
180 static u_int msi_last_irq;
181 static struct mtx msi_lock;
182 
183 static void
msi_enable_source(struct intsrc * isrc)184 msi_enable_source(struct intsrc *isrc)
185 {
186 }
187 
188 static void
msi_disable_source(struct intsrc * isrc,int eoi)189 msi_disable_source(struct intsrc *isrc, int eoi)
190 {
191 
192 	if (eoi == PIC_EOI)
193 		lapic_eoi();
194 }
195 
196 static void
msi_eoi_source(struct intsrc * isrc)197 msi_eoi_source(struct intsrc *isrc)
198 {
199 
200 	lapic_eoi();
201 }
202 
203 static void
msi_enable_intr(struct intsrc * isrc)204 msi_enable_intr(struct intsrc *isrc)
205 {
206 	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
207 
208 	msi = msi->msi_first;
209 	if (msi->msi_enabled == 0) {
210 		for (u_int i = 0; i < msi->msi_count; i++)
211 			apic_enable_vector(msi->msi_cpu, msi->msi_vector + i);
212 	}
213 	msi->msi_enabled++;
214 }
215 
216 static void
msi_disable_intr(struct intsrc * isrc)217 msi_disable_intr(struct intsrc *isrc)
218 {
219 	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
220 
221 	msi = msi->msi_first;
222 
223 	/*
224 	 * Interrupt sources are always registered, but never unregistered.
225 	 * Handle the case where MSIs have all been unregistered.
226 	 */
227 	if (msi == NULL)
228 		return;
229 
230 	msi->msi_enabled--;
231 	if (msi->msi_enabled == 0) {
232 		for (u_int i = 0; i < msi->msi_count; i++)
233 			apic_disable_vector(msi->msi_cpu, msi->msi_vector + i);
234 	}
235 }
236 
237 static int
msi_vector(struct intsrc * isrc)238 msi_vector(struct intsrc *isrc)
239 {
240 	struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
241 
242 	return (msi->msi_irq);
243 }
244 
245 static int
msi_source_pending(struct intsrc * isrc)246 msi_source_pending(struct intsrc *isrc)
247 {
248 
249 	return (0);
250 }
251 
252 static int
msi_config_intr(struct intsrc * isrc,enum intr_trigger trig,enum intr_polarity pol)253 msi_config_intr(struct intsrc *isrc, enum intr_trigger trig,
254     enum intr_polarity pol)
255 {
256 
257 	return (ENODEV);
258 }
259 
260 static int
msi_assign_cpu(struct intsrc * isrc,u_int apic_id)261 msi_assign_cpu(struct intsrc *isrc, u_int apic_id)
262 {
263 	struct msi_intsrc *sib, *msi = (struct msi_intsrc *)isrc;
264 	int old_vector;
265 	u_int old_id;
266 	int error, i, vector;
267 
268 	/*
269 	 * Only allow CPUs to be assigned to the first message for an
270 	 * MSI group.
271 	 */
272 	if (msi->msi_first != msi)
273 		return (EINVAL);
274 
275 #ifdef SMP
276 	if (msix_disable_migration && msi->msi_msix)
277 		return (EINVAL);
278 #endif
279 
280 	/* Store information to free existing irq. */
281 	old_vector = msi->msi_vector;
282 	old_id = msi->msi_cpu;
283 	if (old_id == apic_id)
284 		return (0);
285 
286 	/* Allocate IDT vectors on this cpu. */
287 	if (msi->msi_count > 1) {
288 		KASSERT(!msi->msi_msix, ("MSI-X message group"));
289 		vector = apic_alloc_vectors(apic_id, msi->msi_irqs,
290 		    msi->msi_count, msi->msi_maxcount);
291 	} else
292 		vector = apic_alloc_vector(apic_id, msi->msi_irq);
293 	if (vector == 0)
294 		return (ENOSPC);
295 
296 	/* Must be set before BUS_REMAP_INTR as it may call back into MSI. */
297 	msi->msi_cpu = apic_id;
298 	msi->msi_vector = vector;
299 	if (msi->msi_enabled > 0) {
300 		for (i = 0; i < msi->msi_count; i++)
301 			apic_enable_vector(apic_id, vector + i);
302 	}
303 	error = BUS_REMAP_INTR(device_get_parent(msi->msi_dev), msi->msi_dev,
304 	    msi->msi_irq);
305 	if (error == 0) {
306 		if (bootverbose) {
307 			printf("msi: Assigning %s IRQ %d to local APIC %u vector %u\n",
308 			    msi->msi_msix ? "MSI-X" : "MSI", msi->msi_irq,
309 			    msi->msi_cpu, msi->msi_vector);
310 		}
311 		for (i = 1; i < msi->msi_count; i++) {
312 			sib = (struct msi_intsrc *)intr_lookup_source(
313 			    msi->msi_irqs[i]);
314 			sib->msi_cpu = apic_id;
315 			sib->msi_vector = vector + i;
316 			if (bootverbose)
317 				printf("msi: Assigning MSI IRQ %d to local APIC %u vector %u\n",
318 				    sib->msi_irq, sib->msi_cpu,
319 				    sib->msi_vector);
320 		}
321 	} else {
322 		device_printf(msi->msi_dev,
323 		    "remap irq %u to APIC ID %u failed (error %d)\n",
324 		    msi->msi_irq, apic_id, error);
325 		msi->msi_cpu = old_id;
326 		msi->msi_vector = old_vector;
327 		old_id = apic_id;
328 		old_vector = vector;
329 	}
330 
331 	/*
332 	 * Free the old vector after the new one is established.  This is done
333 	 * to prevent races where we could miss an interrupt.  If BUS_REMAP_INTR
334 	 * failed then we disable and free the new, unused vector(s).
335 	 */
336 	if (msi->msi_enabled > 0) {
337 		for (i = 0; i < msi->msi_count; i++)
338 			apic_disable_vector(old_id, old_vector + i);
339 	}
340 	apic_free_vector(old_id, old_vector, msi->msi_irq);
341 	for (i = 1; i < msi->msi_count; i++)
342 		apic_free_vector(old_id, old_vector + i, msi->msi_irqs[i]);
343 	return (error);
344 }
345 
346 void
msi_init(void)347 msi_init(void)
348 {
349 
350 	/* Check if we have a supported CPU. */
351 	switch (cpu_vendor_id) {
352 	case CPU_VENDOR_INTEL:
353 	case CPU_VENDOR_AMD:
354 	case CPU_VENDOR_HYGON:
355 		break;
356 	case CPU_VENDOR_CENTAUR:
357 		if (CPUID_TO_FAMILY(cpu_id) == 0x6 &&
358 		    CPUID_TO_MODEL(cpu_id) >= 0xf)
359 			break;
360 		/* FALLTHROUGH */
361 	default:
362 		return;
363 	}
364 
365 #ifdef SMP
366 	if (msix_disable_migration == -1) {
367 		/* The default is to allow migration of MSI-X interrupts. */
368 		msix_disable_migration = 0;
369 	}
370 #endif
371 
372 	if (num_msi_irqs == 0)
373 		return;
374 
375 	first_msi_irq = num_io_irqs;
376 	if (num_msi_irqs > UINT_MAX - first_msi_irq)
377 		panic("num_msi_irqs too high");
378 	num_io_irqs = first_msi_irq + num_msi_irqs;
379 
380 	msi_enabled = 1;
381 	intr_register_pic(&msi_pic);
382 	mtx_init(&msi_lock, "msi", NULL, MTX_DEF);
383 }
384 
385 static void
msi_create_source(void)386 msi_create_source(void)
387 {
388 	struct msi_intsrc *msi;
389 	u_int irq;
390 
391 	mtx_lock(&msi_lock);
392 	if (msi_last_irq >= num_msi_irqs) {
393 		mtx_unlock(&msi_lock);
394 		return;
395 	}
396 	irq = msi_last_irq + first_msi_irq;
397 	msi_last_irq++;
398 	mtx_unlock(&msi_lock);
399 
400 	msi = malloc(sizeof(struct msi_intsrc), M_MSI, M_WAITOK | M_ZERO);
401 	msi->msi_intsrc.is_pic = &msi_pic;
402 	msi->msi_irq = irq;
403 	intr_register_source(&msi->msi_intsrc);
404 	nexus_add_irq(irq);
405 }
406 
407 /*
408  * Try to allocate 'count' interrupt sources with contiguous IDT values.
409  */
410 int
msi_alloc(device_t dev,int count,int maxcount,int * irqs)411 msi_alloc(device_t dev, int count, int maxcount, int *irqs)
412 {
413 	struct msi_intsrc *msi, *fsrc;
414 	u_int cpu, domain, *mirqs;
415 	int cnt, i, vector;
416 #ifdef IOMMU
417 	u_int cookies[count];
418 	int error;
419 #endif
420 
421 	if (!msi_enabled)
422 		return (ENXIO);
423 
424 	if (bus_get_domain(dev, &domain) != 0)
425 		domain = 0;
426 
427 	if (count > 1)
428 		mirqs = malloc(count * sizeof(*mirqs), M_MSI, M_WAITOK);
429 	else
430 		mirqs = NULL;
431 again:
432 	mtx_lock(&msi_lock);
433 
434 	/* Try to find 'count' free IRQs. */
435 	cnt = 0;
436 	for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) {
437 		msi = (struct msi_intsrc *)intr_lookup_source(i);
438 
439 		/* End of allocated sources, so break. */
440 		if (msi == NULL)
441 			break;
442 
443 		/* If this is a free one, save its IRQ in the array. */
444 		if (msi->msi_dev == NULL) {
445 			irqs[cnt] = i;
446 			cnt++;
447 			if (cnt == count)
448 				break;
449 		}
450 	}
451 
452 	/* Do we need to create some new sources? */
453 	if (cnt < count) {
454 		/* If we would exceed the max, give up. */
455 		if (i + (count - cnt) > first_msi_irq + num_msi_irqs) {
456 			mtx_unlock(&msi_lock);
457 			free(mirqs, M_MSI);
458 			return (ENXIO);
459 		}
460 		mtx_unlock(&msi_lock);
461 
462 		/* We need count - cnt more sources. */
463 		while (cnt < count) {
464 			msi_create_source();
465 			cnt++;
466 		}
467 		goto again;
468 	}
469 
470 	/* Ok, we now have the IRQs allocated. */
471 	KASSERT(cnt == count, ("count mismatch"));
472 
473 	/* Allocate 'count' IDT vectors. */
474 	cpu = intr_next_cpu(domain);
475 	vector = apic_alloc_vectors(cpu, irqs, count, maxcount);
476 	if (vector == 0) {
477 		mtx_unlock(&msi_lock);
478 		free(mirqs, M_MSI);
479 		return (ENOSPC);
480 	}
481 
482 #ifdef IOMMU
483 	mtx_unlock(&msi_lock);
484 	error = iommu_alloc_msi_intr(dev, cookies, count);
485 	mtx_lock(&msi_lock);
486 	if (error == EOPNOTSUPP)
487 		error = 0;
488 	if (error != 0) {
489 		for (i = 0; i < count; i++)
490 			apic_free_vector(cpu, vector + i, irqs[i]);
491 		mtx_unlock(&msi_lock);
492 		free(mirqs, M_MSI);
493 		return (error);
494 	}
495 	for (i = 0; i < count; i++) {
496 		msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
497 		msi->msi_remap_cookie = cookies[i];
498 	}
499 #endif
500 
501 	/* Assign IDT vectors and make these messages owned by 'dev'. */
502 	fsrc = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
503 	for (i = 0; i < count; i++) {
504 		msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
505 		msi->msi_cpu = cpu;
506 		msi->msi_dev = dev;
507 		msi->msi_vector = vector + i;
508 		if (bootverbose)
509 			printf(
510 		    "msi: routing MSI IRQ %d to local APIC %u vector %u\n",
511 			    msi->msi_irq, msi->msi_cpu, msi->msi_vector);
512 		msi->msi_first = fsrc;
513 		KASSERT(msi->msi_intsrc.is_handlers == 0,
514 		    ("dead MSI has handlers"));
515 	}
516 	fsrc->msi_count = count;
517 	fsrc->msi_maxcount = maxcount;
518 	if (count > 1)
519 		bcopy(irqs, mirqs, count * sizeof(*mirqs));
520 	fsrc->msi_irqs = mirqs;
521 	mtx_unlock(&msi_lock);
522 	return (0);
523 }
524 
525 int
msi_release(int * irqs,int count)526 msi_release(int *irqs, int count)
527 {
528 	struct msi_intsrc *msi, *first;
529 	int i;
530 
531 	mtx_lock(&msi_lock);
532 	first = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
533 	if (first == NULL) {
534 		mtx_unlock(&msi_lock);
535 		return (ENOENT);
536 	}
537 
538 	/* Make sure this isn't an MSI-X message. */
539 	if (first->msi_msix) {
540 		mtx_unlock(&msi_lock);
541 		return (EINVAL);
542 	}
543 
544 	/* Make sure this message is allocated to a group. */
545 	if (first->msi_first == NULL) {
546 		mtx_unlock(&msi_lock);
547 		return (ENXIO);
548 	}
549 
550 	/*
551 	 * Make sure this is the start of a group and that we are releasing
552 	 * the entire group.
553 	 */
554 	if (first->msi_first != first || first->msi_count != count) {
555 		mtx_unlock(&msi_lock);
556 		return (EINVAL);
557 	}
558 	KASSERT(first->msi_dev != NULL, ("unowned group"));
559 
560 	/* Clear all the extra messages in the group. */
561 	for (i = 1; i < count; i++) {
562 		msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
563 		KASSERT(msi->msi_first == first, ("message not in group"));
564 		KASSERT(msi->msi_dev == first->msi_dev, ("owner mismatch"));
565 #ifdef IOMMU
566 		mtx_unlock(&msi_lock);
567 		iommu_unmap_msi_intr(first->msi_dev, msi->msi_remap_cookie);
568 		mtx_lock(&msi_lock);
569 #endif
570 		msi->msi_first = NULL;
571 		msi->msi_dev = NULL;
572 		apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
573 		msi->msi_vector = 0;
574 	}
575 
576 	/* Clear out the first message. */
577 #ifdef IOMMU
578 	mtx_unlock(&msi_lock);
579 	iommu_unmap_msi_intr(first->msi_dev, first->msi_remap_cookie);
580 	mtx_lock(&msi_lock);
581 #endif
582 	first->msi_first = NULL;
583 	first->msi_dev = NULL;
584 	apic_free_vector(first->msi_cpu, first->msi_vector, first->msi_irq);
585 	first->msi_vector = 0;
586 	first->msi_count = 0;
587 	first->msi_maxcount = 0;
588 	free(first->msi_irqs, M_MSI);
589 	first->msi_irqs = NULL;
590 
591 	mtx_unlock(&msi_lock);
592 	return (0);
593 }
594 
595 int
msi_map(int irq,uint64_t * addr,uint32_t * data)596 msi_map(int irq, uint64_t *addr, uint32_t *data)
597 {
598 	struct msi_intsrc *msi;
599 	int error;
600 #ifdef IOMMU
601 	struct msi_intsrc *msi1;
602 	int i, k;
603 #endif
604 
605 	mtx_lock(&msi_lock);
606 	msi = (struct msi_intsrc *)intr_lookup_source(irq);
607 	if (msi == NULL) {
608 		mtx_unlock(&msi_lock);
609 		return (ENOENT);
610 	}
611 
612 	/* Make sure this message is allocated to a device. */
613 	if (msi->msi_dev == NULL) {
614 		mtx_unlock(&msi_lock);
615 		return (ENXIO);
616 	}
617 
618 	/*
619 	 * If this message isn't an MSI-X message, make sure it's part
620 	 * of a group, and switch to the first message in the
621 	 * group.
622 	 */
623 	if (!msi->msi_msix) {
624 		if (msi->msi_first == NULL) {
625 			mtx_unlock(&msi_lock);
626 			return (ENXIO);
627 		}
628 		msi = msi->msi_first;
629 	}
630 
631 #ifdef IOMMU
632 	if (!msi->msi_msix) {
633 		for (k = msi->msi_count - 1, i = first_msi_irq; k > 0 &&
634 		    i < first_msi_irq + num_msi_irqs; i++) {
635 			if (i == msi->msi_irq)
636 				continue;
637 			msi1 = (struct msi_intsrc *)intr_lookup_source(i);
638 			if (!msi1->msi_msix && msi1->msi_first == msi) {
639 				mtx_unlock(&msi_lock);
640 				iommu_map_msi_intr(msi1->msi_dev,
641 				    msi1->msi_cpu, msi1->msi_vector,
642 				    msi1->msi_remap_cookie, NULL, NULL);
643 				k--;
644 				mtx_lock(&msi_lock);
645 			}
646 		}
647 	}
648 	mtx_unlock(&msi_lock);
649 	error = iommu_map_msi_intr(msi->msi_dev, msi->msi_cpu,
650 	    msi->msi_vector, msi->msi_remap_cookie, addr, data);
651 #else
652 	mtx_unlock(&msi_lock);
653 	error = EOPNOTSUPP;
654 #endif
655 	if (error == EOPNOTSUPP && msi->msi_cpu > 0xff) {
656 		printf("%s: unsupported destination APIC ID %u\n", __func__,
657 		    msi->msi_cpu);
658 		error = EINVAL;
659 	}
660 	if (error == EOPNOTSUPP) {
661 		*addr = INTEL_ADDR(msi);
662 		*data = INTEL_DATA(msi);
663 		error = 0;
664 	}
665 	return (error);
666 }
667 
668 int
msix_alloc(device_t dev,int * irq)669 msix_alloc(device_t dev, int *irq)
670 {
671 	struct msi_intsrc *msi;
672 	u_int cpu, domain;
673 	int i, vector;
674 #ifdef IOMMU
675 	u_int cookie;
676 	int error;
677 #endif
678 
679 	if (!msi_enabled)
680 		return (ENXIO);
681 
682 	if (bus_get_domain(dev, &domain) != 0)
683 		domain = 0;
684 
685 again:
686 	mtx_lock(&msi_lock);
687 
688 	/* Find a free IRQ. */
689 	for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) {
690 		msi = (struct msi_intsrc *)intr_lookup_source(i);
691 
692 		/* End of allocated sources, so break. */
693 		if (msi == NULL)
694 			break;
695 
696 		/* Stop at the first free source. */
697 		if (msi->msi_dev == NULL)
698 			break;
699 	}
700 
701 	/* Are all IRQs in use? */
702 	if (i == first_msi_irq + num_msi_irqs) {
703 		mtx_unlock(&msi_lock);
704 		return (ENXIO);
705 	}
706 
707 	/* Do we need to create a new source? */
708 	if (msi == NULL) {
709 		mtx_unlock(&msi_lock);
710 
711 		/* Create a new source. */
712 		msi_create_source();
713 		goto again;
714 	}
715 
716 	/* Allocate an IDT vector. */
717 	cpu = intr_next_cpu(domain);
718 	vector = apic_alloc_vector(cpu, i);
719 	if (vector == 0) {
720 		mtx_unlock(&msi_lock);
721 		return (ENOSPC);
722 	}
723 
724 	msi->msi_dev = dev;
725 #ifdef IOMMU
726 	mtx_unlock(&msi_lock);
727 	error = iommu_alloc_msi_intr(dev, &cookie, 1);
728 	mtx_lock(&msi_lock);
729 	if (error == EOPNOTSUPP)
730 		error = 0;
731 	if (error != 0) {
732 		msi->msi_dev = NULL;
733 		apic_free_vector(cpu, vector, i);
734 		mtx_unlock(&msi_lock);
735 		return (error);
736 	}
737 	msi->msi_remap_cookie = cookie;
738 #endif
739 
740 	if (bootverbose)
741 		printf("msi: routing MSI-X IRQ %d to local APIC %u vector %u\n",
742 		    msi->msi_irq, cpu, vector);
743 
744 	/* Setup source. */
745 	msi->msi_cpu = cpu;
746 	msi->msi_first = msi;
747 	msi->msi_vector = vector;
748 	msi->msi_msix = true;
749 	msi->msi_count = 1;
750 	msi->msi_maxcount = 1;
751 	msi->msi_irqs = NULL;
752 
753 	KASSERT(msi->msi_intsrc.is_handlers == 0, ("dead MSI-X has handlers"));
754 	mtx_unlock(&msi_lock);
755 
756 	*irq = i;
757 	return (0);
758 }
759 
760 int
msix_release(int irq)761 msix_release(int irq)
762 {
763 	struct msi_intsrc *msi;
764 
765 	mtx_lock(&msi_lock);
766 	msi = (struct msi_intsrc *)intr_lookup_source(irq);
767 	if (msi == NULL) {
768 		mtx_unlock(&msi_lock);
769 		return (ENOENT);
770 	}
771 
772 	/* Make sure this is an MSI-X message. */
773 	if (!msi->msi_msix) {
774 		mtx_unlock(&msi_lock);
775 		return (EINVAL);
776 	}
777 
778 	KASSERT(msi->msi_dev != NULL, ("unowned message"));
779 
780 	/* Clear out the message. */
781 #ifdef IOMMU
782 	mtx_unlock(&msi_lock);
783 	iommu_unmap_msi_intr(msi->msi_dev, msi->msi_remap_cookie);
784 	mtx_lock(&msi_lock);
785 #endif
786 	msi->msi_first = NULL;
787 	msi->msi_dev = NULL;
788 	apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
789 	msi->msi_vector = 0;
790 	msi->msi_msix = false;
791 	msi->msi_count = 0;
792 	msi->msi_maxcount = 0;
793 
794 	mtx_unlock(&msi_lock);
795 	return (0);
796 }
797