2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 2006 Yahoo!, Inc.
6 * Written by: John Baldwin <jhb@FreeBSD.org>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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.
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
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.
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
44 #include <sys/param.h>
46 #include <sys/kernel.h>
47 #include <sys/limits.h>
49 #include <sys/malloc.h>
50 #include <sys/mutex.h>
52 #include <sys/sysctl.h>
53 #include <sys/systm.h>
54 #include <x86/apicreg.h>
55 #include <machine/cputypes.h>
56 #include <machine/md_var.h>
57 #include <machine/frame.h>
58 #include <machine/intr_machdep.h>
59 #include <x86/apicvar.h>
60 #include <x86/iommu/iommu_intrmap.h>
61 #include <machine/specialreg.h>
62 #include <dev/pci/pcivar.h>
64 /* Fields in address for Intel MSI messages. */
65 #define MSI_INTEL_ADDR_DEST 0x000ff000
66 #define MSI_INTEL_ADDR_RH 0x00000008
67 # define MSI_INTEL_ADDR_RH_ON 0x00000008
68 # define MSI_INTEL_ADDR_RH_OFF 0x00000000
69 #define MSI_INTEL_ADDR_DM 0x00000004
70 # define MSI_INTEL_ADDR_DM_PHYSICAL 0x00000000
71 # define MSI_INTEL_ADDR_DM_LOGICAL 0x00000004
73 /* Fields in data for Intel MSI messages. */
74 #define MSI_INTEL_DATA_TRGRMOD IOART_TRGRMOD /* Trigger mode. */
75 # define MSI_INTEL_DATA_TRGREDG IOART_TRGREDG
76 # define MSI_INTEL_DATA_TRGRLVL IOART_TRGRLVL
77 #define MSI_INTEL_DATA_LEVEL 0x00004000 /* Polarity. */
78 # define MSI_INTEL_DATA_DEASSERT 0x00000000
79 # define MSI_INTEL_DATA_ASSERT 0x00004000
80 #define MSI_INTEL_DATA_DELMOD IOART_DELMOD /* Delivery mode. */
81 # define MSI_INTEL_DATA_DELFIXED IOART_DELFIXED
82 # define MSI_INTEL_DATA_DELLOPRI IOART_DELLOPRI
83 # define MSI_INTEL_DATA_DELSMI IOART_DELSMI
84 # define MSI_INTEL_DATA_DELNMI IOART_DELNMI
85 # define MSI_INTEL_DATA_DELINIT IOART_DELINIT
86 # define MSI_INTEL_DATA_DELEXINT IOART_DELEXINT
87 #define MSI_INTEL_DATA_INTVEC IOART_INTVEC /* Interrupt vector. */
90 * Build Intel MSI message and data values from a source. AMD64 systems
91 * seem to be compatible, so we use the same function for both.
93 #define INTEL_ADDR(msi) \
94 (MSI_INTEL_ADDR_BASE | (msi)->msi_cpu << 12 | \
95 MSI_INTEL_ADDR_RH_OFF | MSI_INTEL_ADDR_DM_PHYSICAL)
96 #define INTEL_DATA(msi) \
97 (MSI_INTEL_DATA_TRGREDG | MSI_INTEL_DATA_DELFIXED | (msi)->msi_vector)
99 static MALLOC_DEFINE(M_MSI, "msi", "PCI MSI");
102 * MSI sources are bunched into groups. This is because MSI forces
103 * all of the messages to share the address and data registers and
104 * thus certain properties (such as the local APIC ID target on x86).
105 * Each group has a 'first' source that contains information global to
106 * the group. These fields are marked with (g) below.
108 * Note that local APIC ID is kind of special. Each message will be
109 * assigned an ID by the system; however, a group will use the ID from
112 * For MSI-X, each message is isolated.
115 struct intsrc msi_intsrc;
116 device_t msi_dev; /* Owning device. (g) */
117 struct msi_intsrc *msi_first; /* First source in group. */
118 u_int msi_irq; /* IRQ cookie. */
119 u_int msi_msix; /* MSI-X message. */
120 u_int msi_vector:8; /* IDT vector. */
121 u_int msi_cpu; /* Local APIC ID. (g) */
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_irqs; /* Group's IRQ list. (g) */
125 u_int msi_remap_cookie;
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);
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,
150 .pic_config_intr = msi_config_intr,
151 .pic_assign_cpu = msi_assign_cpu,
152 .pic_reprogram_pin = NULL,
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");
159 u_int num_msi_irqs = 512;
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");
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:
169 * -1: automatic detection by FreeBSD
170 * 0: enable migration
171 * 1: disable migration
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");
179 static int msi_enabled;
180 static u_int msi_last_irq;
181 static struct mtx msi_lock;
184 msi_enable_source(struct intsrc *isrc)
189 msi_disable_source(struct intsrc *isrc, int eoi)
197 msi_eoi_source(struct intsrc *isrc)
204 msi_enable_intr(struct intsrc *isrc)
206 struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
208 apic_enable_vector(msi->msi_cpu, msi->msi_vector);
212 msi_disable_intr(struct intsrc *isrc)
214 struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
216 apic_disable_vector(msi->msi_cpu, msi->msi_vector);
220 msi_vector(struct intsrc *isrc)
222 struct msi_intsrc *msi = (struct msi_intsrc *)isrc;
224 return (msi->msi_irq);
228 msi_source_pending(struct intsrc *isrc)
235 msi_config_intr(struct intsrc *isrc, enum intr_trigger trig,
236 enum intr_polarity pol)
243 msi_assign_cpu(struct intsrc *isrc, u_int apic_id)
245 struct msi_intsrc *sib, *msi = (struct msi_intsrc *)isrc;
251 * Only allow CPUs to be assigned to the first message for an
254 if (msi->msi_first != msi)
258 if (msix_disable_migration && msi->msi_msix)
262 /* Store information to free existing irq. */
263 old_vector = msi->msi_vector;
264 old_id = msi->msi_cpu;
265 if (old_id == apic_id)
268 /* Allocate IDT vectors on this cpu. */
269 if (msi->msi_count > 1) {
270 KASSERT(msi->msi_msix == 0, ("MSI-X message group"));
271 vector = apic_alloc_vectors(apic_id, msi->msi_irqs,
272 msi->msi_count, msi->msi_maxcount);
274 vector = apic_alloc_vector(apic_id, msi->msi_irq);
278 msi->msi_cpu = apic_id;
279 msi->msi_vector = vector;
280 if (msi->msi_intsrc.is_handlers > 0)
281 apic_enable_vector(msi->msi_cpu, msi->msi_vector);
283 printf("msi: Assigning %s IRQ %d to local APIC %u vector %u\n",
284 msi->msi_msix ? "MSI-X" : "MSI", msi->msi_irq,
285 msi->msi_cpu, msi->msi_vector);
286 for (i = 1; i < msi->msi_count; i++) {
287 sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]);
288 sib->msi_cpu = apic_id;
289 sib->msi_vector = vector + i;
290 if (sib->msi_intsrc.is_handlers > 0)
291 apic_enable_vector(sib->msi_cpu, sib->msi_vector);
294 "msi: Assigning MSI IRQ %d to local APIC %u vector %u\n",
295 sib->msi_irq, sib->msi_cpu, sib->msi_vector);
297 BUS_REMAP_INTR(device_get_parent(msi->msi_dev), msi->msi_dev,
301 * Free the old vector after the new one is established. This is done
302 * to prevent races where we could miss an interrupt.
304 if (msi->msi_intsrc.is_handlers > 0)
305 apic_disable_vector(old_id, old_vector);
306 apic_free_vector(old_id, old_vector, msi->msi_irq);
307 for (i = 1; i < msi->msi_count; i++) {
308 sib = (struct msi_intsrc *)intr_lookup_source(msi->msi_irqs[i]);
309 if (sib->msi_intsrc.is_handlers > 0)
310 apic_disable_vector(old_id, old_vector + i);
311 apic_free_vector(old_id, old_vector + i, msi->msi_irqs[i]);
320 /* Check if we have a supported CPU. */
321 switch (cpu_vendor_id) {
322 case CPU_VENDOR_INTEL:
325 case CPU_VENDOR_CENTAUR:
326 if (CPUID_TO_FAMILY(cpu_id) == 0x6 &&
327 CPUID_TO_MODEL(cpu_id) >= 0xf)
335 if (msix_disable_migration == -1) {
336 /* The default is to allow migration of MSI-X interrupts. */
337 msix_disable_migration = 0;
341 if (num_msi_irqs == 0)
344 first_msi_irq = num_io_irqs;
345 if (num_msi_irqs > UINT_MAX - first_msi_irq)
346 panic("num_msi_irqs too high");
347 num_io_irqs = first_msi_irq + num_msi_irqs;
350 intr_register_pic(&msi_pic);
351 mtx_init(&msi_lock, "msi", NULL, MTX_DEF);
355 msi_create_source(void)
357 struct msi_intsrc *msi;
361 if (msi_last_irq >= num_msi_irqs) {
362 mtx_unlock(&msi_lock);
365 irq = msi_last_irq + first_msi_irq;
367 mtx_unlock(&msi_lock);
369 msi = malloc(sizeof(struct msi_intsrc), M_MSI, M_WAITOK | M_ZERO);
370 msi->msi_intsrc.is_pic = &msi_pic;
372 intr_register_source(&msi->msi_intsrc);
377 * Try to allocate 'count' interrupt sources with contiguous IDT values.
380 msi_alloc(device_t dev, int count, int maxcount, int *irqs)
382 struct msi_intsrc *msi, *fsrc;
383 u_int cpu, domain, *mirqs;
386 u_int cookies[count];
393 if (bus_get_domain(dev, &domain) != 0)
397 mirqs = malloc(count * sizeof(*mirqs), M_MSI, M_WAITOK);
403 /* Try to find 'count' free IRQs. */
405 for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) {
406 msi = (struct msi_intsrc *)intr_lookup_source(i);
408 /* End of allocated sources, so break. */
412 /* If this is a free one, save its IRQ in the array. */
413 if (msi->msi_dev == NULL) {
421 /* Do we need to create some new sources? */
423 /* If we would exceed the max, give up. */
424 if (i + (count - cnt) > first_msi_irq + num_msi_irqs) {
425 mtx_unlock(&msi_lock);
429 mtx_unlock(&msi_lock);
431 /* We need count - cnt more sources. */
432 while (cnt < count) {
439 /* Ok, we now have the IRQs allocated. */
440 KASSERT(cnt == count, ("count mismatch"));
442 /* Allocate 'count' IDT vectors. */
443 cpu = intr_next_cpu(domain);
444 vector = apic_alloc_vectors(cpu, irqs, count, maxcount);
446 mtx_unlock(&msi_lock);
452 mtx_unlock(&msi_lock);
453 error = iommu_alloc_msi_intr(dev, cookies, count);
455 if (error == EOPNOTSUPP)
458 for (i = 0; i < count; i++)
459 apic_free_vector(cpu, vector + i, irqs[i]);
463 for (i = 0; i < count; i++) {
464 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
465 msi->msi_remap_cookie = cookies[i];
469 /* Assign IDT vectors and make these messages owned by 'dev'. */
470 fsrc = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
471 for (i = 0; i < count; i++) {
472 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
475 msi->msi_vector = vector + i;
478 "msi: routing MSI IRQ %d to local APIC %u vector %u\n",
479 msi->msi_irq, msi->msi_cpu, msi->msi_vector);
480 msi->msi_first = fsrc;
481 KASSERT(msi->msi_intsrc.is_handlers == 0,
482 ("dead MSI has handlers"));
484 fsrc->msi_count = count;
485 fsrc->msi_maxcount = maxcount;
487 bcopy(irqs, mirqs, count * sizeof(*mirqs));
488 fsrc->msi_irqs = mirqs;
489 mtx_unlock(&msi_lock);
494 msi_release(int *irqs, int count)
496 struct msi_intsrc *msi, *first;
500 first = (struct msi_intsrc *)intr_lookup_source(irqs[0]);
502 mtx_unlock(&msi_lock);
506 /* Make sure this isn't an MSI-X message. */
507 if (first->msi_msix) {
508 mtx_unlock(&msi_lock);
512 /* Make sure this message is allocated to a group. */
513 if (first->msi_first == NULL) {
514 mtx_unlock(&msi_lock);
519 * Make sure this is the start of a group and that we are releasing
522 if (first->msi_first != first || first->msi_count != count) {
523 mtx_unlock(&msi_lock);
526 KASSERT(first->msi_dev != NULL, ("unowned group"));
528 /* Clear all the extra messages in the group. */
529 for (i = 1; i < count; i++) {
530 msi = (struct msi_intsrc *)intr_lookup_source(irqs[i]);
531 KASSERT(msi->msi_first == first, ("message not in group"));
532 KASSERT(msi->msi_dev == first->msi_dev, ("owner mismatch"));
534 iommu_unmap_msi_intr(first->msi_dev, msi->msi_remap_cookie);
536 msi->msi_first = NULL;
538 apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
542 /* Clear out the first message. */
544 mtx_unlock(&msi_lock);
545 iommu_unmap_msi_intr(first->msi_dev, first->msi_remap_cookie);
548 first->msi_first = NULL;
549 first->msi_dev = NULL;
550 apic_free_vector(first->msi_cpu, first->msi_vector, first->msi_irq);
551 first->msi_vector = 0;
552 first->msi_count = 0;
553 first->msi_maxcount = 0;
554 free(first->msi_irqs, M_MSI);
555 first->msi_irqs = NULL;
557 mtx_unlock(&msi_lock);
562 msi_map(int irq, uint64_t *addr, uint32_t *data)
564 struct msi_intsrc *msi;
567 struct msi_intsrc *msi1;
572 msi = (struct msi_intsrc *)intr_lookup_source(irq);
574 mtx_unlock(&msi_lock);
578 /* Make sure this message is allocated to a device. */
579 if (msi->msi_dev == NULL) {
580 mtx_unlock(&msi_lock);
585 * If this message isn't an MSI-X message, make sure it's part
586 * of a group, and switch to the first message in the
589 if (!msi->msi_msix) {
590 if (msi->msi_first == NULL) {
591 mtx_unlock(&msi_lock);
594 msi = msi->msi_first;
598 if (!msi->msi_msix) {
599 for (k = msi->msi_count - 1, i = first_msi_irq; k > 0 &&
600 i < first_msi_irq + num_msi_irqs; i++) {
601 if (i == msi->msi_irq)
603 msi1 = (struct msi_intsrc *)intr_lookup_source(i);
604 if (!msi1->msi_msix && msi1->msi_first == msi) {
605 mtx_unlock(&msi_lock);
606 iommu_map_msi_intr(msi1->msi_dev,
607 msi1->msi_cpu, msi1->msi_vector,
608 msi1->msi_remap_cookie, NULL, NULL);
614 mtx_unlock(&msi_lock);
615 error = iommu_map_msi_intr(msi->msi_dev, msi->msi_cpu,
616 msi->msi_vector, msi->msi_remap_cookie, addr, data);
618 mtx_unlock(&msi_lock);
621 if (error == EOPNOTSUPP) {
622 *addr = INTEL_ADDR(msi);
623 *data = INTEL_DATA(msi);
630 msix_alloc(device_t dev, int *irq)
632 struct msi_intsrc *msi;
643 if (bus_get_domain(dev, &domain) != 0)
649 /* Find a free IRQ. */
650 for (i = first_msi_irq; i < first_msi_irq + num_msi_irqs; i++) {
651 msi = (struct msi_intsrc *)intr_lookup_source(i);
653 /* End of allocated sources, so break. */
657 /* Stop at the first free source. */
658 if (msi->msi_dev == NULL)
662 /* Are all IRQs in use? */
663 if (i == first_msi_irq + num_msi_irqs) {
664 mtx_unlock(&msi_lock);
668 /* Do we need to create a new source? */
670 mtx_unlock(&msi_lock);
672 /* Create a new source. */
677 /* Allocate an IDT vector. */
678 cpu = intr_next_cpu(domain);
679 vector = apic_alloc_vector(cpu, i);
681 mtx_unlock(&msi_lock);
687 mtx_unlock(&msi_lock);
688 error = iommu_alloc_msi_intr(dev, &cookie, 1);
690 if (error == EOPNOTSUPP)
694 apic_free_vector(cpu, vector, i);
697 msi->msi_remap_cookie = cookie;
701 printf("msi: routing MSI-X IRQ %d to local APIC %u vector %u\n",
702 msi->msi_irq, cpu, vector);
706 msi->msi_first = msi;
707 msi->msi_vector = vector;
710 msi->msi_maxcount = 1;
711 msi->msi_irqs = NULL;
713 KASSERT(msi->msi_intsrc.is_handlers == 0, ("dead MSI-X has handlers"));
714 mtx_unlock(&msi_lock);
721 msix_release(int irq)
723 struct msi_intsrc *msi;
726 msi = (struct msi_intsrc *)intr_lookup_source(irq);
728 mtx_unlock(&msi_lock);
732 /* Make sure this is an MSI-X message. */
733 if (!msi->msi_msix) {
734 mtx_unlock(&msi_lock);
738 KASSERT(msi->msi_dev != NULL, ("unowned message"));
740 /* Clear out the message. */
742 mtx_unlock(&msi_lock);
743 iommu_unmap_msi_intr(msi->msi_dev, msi->msi_remap_cookie);
746 msi->msi_first = NULL;
748 apic_free_vector(msi->msi_cpu, msi->msi_vector, msi->msi_irq);
752 msi->msi_maxcount = 0;
754 mtx_unlock(&msi_lock);