1 // SPDX-License-Identifier: GPL-2.0
3 * PCI Message Signaled Interrupt (MSI)
5 * Copyright (C) 2003-2004 Intel
6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
7 * Copyright (C) 2016 Christoph Hellwig.
10 #include <linux/err.h>
12 #include <linux/irq.h>
13 #include <linux/interrupt.h>
14 #include <linux/export.h>
15 #include <linux/ioport.h>
16 #include <linux/pci.h>
17 #include <linux/proc_fs.h>
18 #include <linux/msi.h>
19 #include <linux/smp.h>
20 #include <linux/errno.h>
22 #include <linux/acpi_iort.h>
23 #include <linux/slab.h>
24 #include <linux/irqdomain.h>
25 #include <linux/of_irq.h>
29 static int pci_msi_enable
= 1;
30 int pci_msi_ignore_mask
;
32 #define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1)
34 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
35 static int pci_msi_setup_msi_irqs(struct pci_dev
*dev
, int nvec
, int type
)
37 struct irq_domain
*domain
;
39 domain
= dev_get_msi_domain(&dev
->dev
);
40 if (domain
&& irq_domain_is_hierarchy(domain
))
41 return msi_domain_alloc_irqs(domain
, &dev
->dev
, nvec
);
43 return arch_setup_msi_irqs(dev
, nvec
, type
);
46 static void pci_msi_teardown_msi_irqs(struct pci_dev
*dev
)
48 struct irq_domain
*domain
;
50 domain
= dev_get_msi_domain(&dev
->dev
);
51 if (domain
&& irq_domain_is_hierarchy(domain
))
52 msi_domain_free_irqs(domain
, &dev
->dev
);
54 arch_teardown_msi_irqs(dev
);
57 #define pci_msi_setup_msi_irqs arch_setup_msi_irqs
58 #define pci_msi_teardown_msi_irqs arch_teardown_msi_irqs
63 int __weak
arch_setup_msi_irq(struct pci_dev
*dev
, struct msi_desc
*desc
)
65 struct msi_controller
*chip
= dev
->bus
->msi
;
68 if (!chip
|| !chip
->setup_irq
)
71 err
= chip
->setup_irq(chip
, dev
, desc
);
75 irq_set_chip_data(desc
->irq
, chip
);
80 void __weak
arch_teardown_msi_irq(unsigned int irq
)
82 struct msi_controller
*chip
= irq_get_chip_data(irq
);
84 if (!chip
|| !chip
->teardown_irq
)
87 chip
->teardown_irq(chip
, irq
);
90 int __weak
arch_setup_msi_irqs(struct pci_dev
*dev
, int nvec
, int type
)
92 struct msi_controller
*chip
= dev
->bus
->msi
;
93 struct msi_desc
*entry
;
96 if (chip
&& chip
->setup_irqs
)
97 return chip
->setup_irqs(chip
, dev
, nvec
, type
);
99 * If an architecture wants to support multiple MSI, it needs to
100 * override arch_setup_msi_irqs()
102 if (type
== PCI_CAP_ID_MSI
&& nvec
> 1)
105 for_each_pci_msi_entry(entry
, dev
) {
106 ret
= arch_setup_msi_irq(dev
, entry
);
117 * We have a default implementation available as a separate non-weak
118 * function, as it is used by the Xen x86 PCI code
120 void default_teardown_msi_irqs(struct pci_dev
*dev
)
123 struct msi_desc
*entry
;
125 for_each_pci_msi_entry(entry
, dev
)
127 for (i
= 0; i
< entry
->nvec_used
; i
++)
128 arch_teardown_msi_irq(entry
->irq
+ i
);
131 void __weak
arch_teardown_msi_irqs(struct pci_dev
*dev
)
133 return default_teardown_msi_irqs(dev
);
136 static void default_restore_msi_irq(struct pci_dev
*dev
, int irq
)
138 struct msi_desc
*entry
;
141 if (dev
->msix_enabled
) {
142 for_each_pci_msi_entry(entry
, dev
) {
143 if (irq
== entry
->irq
)
146 } else if (dev
->msi_enabled
) {
147 entry
= irq_get_msi_desc(irq
);
151 __pci_write_msi_msg(entry
, &entry
->msg
);
154 void __weak
arch_restore_msi_irqs(struct pci_dev
*dev
)
156 return default_restore_msi_irqs(dev
);
159 static inline __attribute_const__ u32
msi_mask(unsigned x
)
161 /* Don't shift by >= width of type */
164 return (1 << (1 << x
)) - 1;
168 * PCI 2.3 does not specify mask bits for each MSI interrupt. Attempting to
169 * mask all MSI interrupts by clearing the MSI enable bit does not work
170 * reliably as devices without an INTx disable bit will then generate a
171 * level IRQ which will never be cleared.
173 u32
__pci_msi_desc_mask_irq(struct msi_desc
*desc
, u32 mask
, u32 flag
)
175 u32 mask_bits
= desc
->masked
;
177 if (pci_msi_ignore_mask
|| !desc
->msi_attrib
.maskbit
)
182 pci_write_config_dword(msi_desc_to_pci_dev(desc
), desc
->mask_pos
,
188 static void msi_mask_irq(struct msi_desc
*desc
, u32 mask
, u32 flag
)
190 desc
->masked
= __pci_msi_desc_mask_irq(desc
, mask
, flag
);
193 static void __iomem
*pci_msix_desc_addr(struct msi_desc
*desc
)
195 if (desc
->msi_attrib
.is_virtual
)
198 return desc
->mask_base
+
199 desc
->msi_attrib
.entry_nr
* PCI_MSIX_ENTRY_SIZE
;
203 * This internal function does not flush PCI writes to the device.
204 * All users must ensure that they read from the device before either
205 * assuming that the device state is up to date, or returning out of this
206 * file. This saves a few milliseconds when initialising devices with lots
207 * of MSI-X interrupts.
209 u32
__pci_msix_desc_mask_irq(struct msi_desc
*desc
, u32 flag
)
211 u32 mask_bits
= desc
->masked
;
212 void __iomem
*desc_addr
;
214 if (pci_msi_ignore_mask
)
216 desc_addr
= pci_msix_desc_addr(desc
);
220 mask_bits
&= ~PCI_MSIX_ENTRY_CTRL_MASKBIT
;
222 mask_bits
|= PCI_MSIX_ENTRY_CTRL_MASKBIT
;
224 writel(mask_bits
, desc_addr
+ PCI_MSIX_ENTRY_VECTOR_CTRL
);
229 static void msix_mask_irq(struct msi_desc
*desc
, u32 flag
)
231 desc
->masked
= __pci_msix_desc_mask_irq(desc
, flag
);
234 static void msi_set_mask_bit(struct irq_data
*data
, u32 flag
)
236 struct msi_desc
*desc
= irq_data_get_msi_desc(data
);
238 if (desc
->msi_attrib
.is_msix
) {
239 msix_mask_irq(desc
, flag
);
240 readl(desc
->mask_base
); /* Flush write to device */
242 unsigned offset
= data
->irq
- desc
->irq
;
243 msi_mask_irq(desc
, 1 << offset
, flag
<< offset
);
248 * pci_msi_mask_irq - Generic IRQ chip callback to mask PCI/MSI interrupts
249 * @data: pointer to irqdata associated to that interrupt
251 void pci_msi_mask_irq(struct irq_data
*data
)
253 msi_set_mask_bit(data
, 1);
255 EXPORT_SYMBOL_GPL(pci_msi_mask_irq
);
258 * pci_msi_unmask_irq - Generic IRQ chip callback to unmask PCI/MSI interrupts
259 * @data: pointer to irqdata associated to that interrupt
261 void pci_msi_unmask_irq(struct irq_data
*data
)
263 msi_set_mask_bit(data
, 0);
265 EXPORT_SYMBOL_GPL(pci_msi_unmask_irq
);
267 void default_restore_msi_irqs(struct pci_dev
*dev
)
269 struct msi_desc
*entry
;
271 for_each_pci_msi_entry(entry
, dev
)
272 default_restore_msi_irq(dev
, entry
->irq
);
275 void __pci_read_msi_msg(struct msi_desc
*entry
, struct msi_msg
*msg
)
277 struct pci_dev
*dev
= msi_desc_to_pci_dev(entry
);
279 BUG_ON(dev
->current_state
!= PCI_D0
);
281 if (entry
->msi_attrib
.is_msix
) {
282 void __iomem
*base
= pci_msix_desc_addr(entry
);
289 msg
->address_lo
= readl(base
+ PCI_MSIX_ENTRY_LOWER_ADDR
);
290 msg
->address_hi
= readl(base
+ PCI_MSIX_ENTRY_UPPER_ADDR
);
291 msg
->data
= readl(base
+ PCI_MSIX_ENTRY_DATA
);
293 int pos
= dev
->msi_cap
;
296 pci_read_config_dword(dev
, pos
+ PCI_MSI_ADDRESS_LO
,
298 if (entry
->msi_attrib
.is_64
) {
299 pci_read_config_dword(dev
, pos
+ PCI_MSI_ADDRESS_HI
,
301 pci_read_config_word(dev
, pos
+ PCI_MSI_DATA_64
, &data
);
304 pci_read_config_word(dev
, pos
+ PCI_MSI_DATA_32
, &data
);
310 void __pci_write_msi_msg(struct msi_desc
*entry
, struct msi_msg
*msg
)
312 struct pci_dev
*dev
= msi_desc_to_pci_dev(entry
);
314 if (dev
->current_state
!= PCI_D0
|| pci_dev_is_disconnected(dev
)) {
315 /* Don't touch the hardware now */
316 } else if (entry
->msi_attrib
.is_msix
) {
317 void __iomem
*base
= pci_msix_desc_addr(entry
);
322 writel(msg
->address_lo
, base
+ PCI_MSIX_ENTRY_LOWER_ADDR
);
323 writel(msg
->address_hi
, base
+ PCI_MSIX_ENTRY_UPPER_ADDR
);
324 writel(msg
->data
, base
+ PCI_MSIX_ENTRY_DATA
);
326 int pos
= dev
->msi_cap
;
329 pci_read_config_word(dev
, pos
+ PCI_MSI_FLAGS
, &msgctl
);
330 msgctl
&= ~PCI_MSI_FLAGS_QSIZE
;
331 msgctl
|= entry
->msi_attrib
.multiple
<< 4;
332 pci_write_config_word(dev
, pos
+ PCI_MSI_FLAGS
, msgctl
);
334 pci_write_config_dword(dev
, pos
+ PCI_MSI_ADDRESS_LO
,
336 if (entry
->msi_attrib
.is_64
) {
337 pci_write_config_dword(dev
, pos
+ PCI_MSI_ADDRESS_HI
,
339 pci_write_config_word(dev
, pos
+ PCI_MSI_DATA_64
,
342 pci_write_config_word(dev
, pos
+ PCI_MSI_DATA_32
,
350 if (entry
->write_msi_msg
)
351 entry
->write_msi_msg(entry
, entry
->write_msi_msg_data
);
355 void pci_write_msi_msg(unsigned int irq
, struct msi_msg
*msg
)
357 struct msi_desc
*entry
= irq_get_msi_desc(irq
);
359 __pci_write_msi_msg(entry
, msg
);
361 EXPORT_SYMBOL_GPL(pci_write_msi_msg
);
363 static void free_msi_irqs(struct pci_dev
*dev
)
365 struct list_head
*msi_list
= dev_to_msi_list(&dev
->dev
);
366 struct msi_desc
*entry
, *tmp
;
367 struct attribute
**msi_attrs
;
368 struct device_attribute
*dev_attr
;
371 for_each_pci_msi_entry(entry
, dev
)
373 for (i
= 0; i
< entry
->nvec_used
; i
++)
374 BUG_ON(irq_has_action(entry
->irq
+ i
));
376 pci_msi_teardown_msi_irqs(dev
);
378 list_for_each_entry_safe(entry
, tmp
, msi_list
, list
) {
379 if (entry
->msi_attrib
.is_msix
) {
380 if (list_is_last(&entry
->list
, msi_list
))
381 iounmap(entry
->mask_base
);
384 list_del(&entry
->list
);
385 free_msi_entry(entry
);
388 if (dev
->msi_irq_groups
) {
389 sysfs_remove_groups(&dev
->dev
.kobj
, dev
->msi_irq_groups
);
390 msi_attrs
= dev
->msi_irq_groups
[0]->attrs
;
391 while (msi_attrs
[count
]) {
392 dev_attr
= container_of(msi_attrs
[count
],
393 struct device_attribute
, attr
);
394 kfree(dev_attr
->attr
.name
);
399 kfree(dev
->msi_irq_groups
[0]);
400 kfree(dev
->msi_irq_groups
);
401 dev
->msi_irq_groups
= NULL
;
405 static void pci_intx_for_msi(struct pci_dev
*dev
, int enable
)
407 if (!(dev
->dev_flags
& PCI_DEV_FLAGS_MSI_INTX_DISABLE_BUG
))
408 pci_intx(dev
, enable
);
411 static void __pci_restore_msi_state(struct pci_dev
*dev
)
414 struct msi_desc
*entry
;
416 if (!dev
->msi_enabled
)
419 entry
= irq_get_msi_desc(dev
->irq
);
421 pci_intx_for_msi(dev
, 0);
422 pci_msi_set_enable(dev
, 0);
423 arch_restore_msi_irqs(dev
);
425 pci_read_config_word(dev
, dev
->msi_cap
+ PCI_MSI_FLAGS
, &control
);
426 msi_mask_irq(entry
, msi_mask(entry
->msi_attrib
.multi_cap
),
428 control
&= ~PCI_MSI_FLAGS_QSIZE
;
429 control
|= (entry
->msi_attrib
.multiple
<< 4) | PCI_MSI_FLAGS_ENABLE
;
430 pci_write_config_word(dev
, dev
->msi_cap
+ PCI_MSI_FLAGS
, control
);
433 static void __pci_restore_msix_state(struct pci_dev
*dev
)
435 struct msi_desc
*entry
;
437 if (!dev
->msix_enabled
)
439 BUG_ON(list_empty(dev_to_msi_list(&dev
->dev
)));
441 /* route the table */
442 pci_intx_for_msi(dev
, 0);
443 pci_msix_clear_and_set_ctrl(dev
, 0,
444 PCI_MSIX_FLAGS_ENABLE
| PCI_MSIX_FLAGS_MASKALL
);
446 arch_restore_msi_irqs(dev
);
447 for_each_pci_msi_entry(entry
, dev
)
448 msix_mask_irq(entry
, entry
->masked
);
450 pci_msix_clear_and_set_ctrl(dev
, PCI_MSIX_FLAGS_MASKALL
, 0);
453 void pci_restore_msi_state(struct pci_dev
*dev
)
455 __pci_restore_msi_state(dev
);
456 __pci_restore_msix_state(dev
);
458 EXPORT_SYMBOL_GPL(pci_restore_msi_state
);
460 static ssize_t
msi_mode_show(struct device
*dev
, struct device_attribute
*attr
,
463 struct msi_desc
*entry
;
467 retval
= kstrtoul(attr
->attr
.name
, 10, &irq
);
471 entry
= irq_get_msi_desc(irq
);
473 return sprintf(buf
, "%s\n",
474 entry
->msi_attrib
.is_msix
? "msix" : "msi");
479 static int populate_msi_sysfs(struct pci_dev
*pdev
)
481 struct attribute
**msi_attrs
;
482 struct attribute
*msi_attr
;
483 struct device_attribute
*msi_dev_attr
;
484 struct attribute_group
*msi_irq_group
;
485 const struct attribute_group
**msi_irq_groups
;
486 struct msi_desc
*entry
;
492 /* Determine how many msi entries we have */
493 for_each_pci_msi_entry(entry
, pdev
)
494 num_msi
+= entry
->nvec_used
;
498 /* Dynamically create the MSI attributes for the PCI device */
499 msi_attrs
= kcalloc(num_msi
+ 1, sizeof(void *), GFP_KERNEL
);
502 for_each_pci_msi_entry(entry
, pdev
) {
503 for (i
= 0; i
< entry
->nvec_used
; i
++) {
504 msi_dev_attr
= kzalloc(sizeof(*msi_dev_attr
), GFP_KERNEL
);
507 msi_attrs
[count
] = &msi_dev_attr
->attr
;
509 sysfs_attr_init(&msi_dev_attr
->attr
);
510 msi_dev_attr
->attr
.name
= kasprintf(GFP_KERNEL
, "%d",
512 if (!msi_dev_attr
->attr
.name
)
514 msi_dev_attr
->attr
.mode
= S_IRUGO
;
515 msi_dev_attr
->show
= msi_mode_show
;
520 msi_irq_group
= kzalloc(sizeof(*msi_irq_group
), GFP_KERNEL
);
523 msi_irq_group
->name
= "msi_irqs";
524 msi_irq_group
->attrs
= msi_attrs
;
526 msi_irq_groups
= kcalloc(2, sizeof(void *), GFP_KERNEL
);
528 goto error_irq_group
;
529 msi_irq_groups
[0] = msi_irq_group
;
531 ret
= sysfs_create_groups(&pdev
->dev
.kobj
, msi_irq_groups
);
533 goto error_irq_groups
;
534 pdev
->msi_irq_groups
= msi_irq_groups
;
539 kfree(msi_irq_groups
);
541 kfree(msi_irq_group
);
544 msi_attr
= msi_attrs
[count
];
546 msi_dev_attr
= container_of(msi_attr
, struct device_attribute
, attr
);
547 kfree(msi_attr
->name
);
550 msi_attr
= msi_attrs
[count
];
556 static struct msi_desc
*
557 msi_setup_entry(struct pci_dev
*dev
, int nvec
, struct irq_affinity
*affd
)
559 struct irq_affinity_desc
*masks
= NULL
;
560 struct msi_desc
*entry
;
564 masks
= irq_create_affinity_masks(nvec
, affd
);
566 /* MSI Entry Initialization */
567 entry
= alloc_msi_entry(&dev
->dev
, nvec
, masks
);
571 pci_read_config_word(dev
, dev
->msi_cap
+ PCI_MSI_FLAGS
, &control
);
573 entry
->msi_attrib
.is_msix
= 0;
574 entry
->msi_attrib
.is_64
= !!(control
& PCI_MSI_FLAGS_64BIT
);
575 entry
->msi_attrib
.is_virtual
= 0;
576 entry
->msi_attrib
.entry_nr
= 0;
577 entry
->msi_attrib
.maskbit
= !!(control
& PCI_MSI_FLAGS_MASKBIT
);
578 entry
->msi_attrib
.default_irq
= dev
->irq
; /* Save IOAPIC IRQ */
579 entry
->msi_attrib
.multi_cap
= (control
& PCI_MSI_FLAGS_QMASK
) >> 1;
580 entry
->msi_attrib
.multiple
= ilog2(__roundup_pow_of_two(nvec
));
582 if (control
& PCI_MSI_FLAGS_64BIT
)
583 entry
->mask_pos
= dev
->msi_cap
+ PCI_MSI_MASK_64
;
585 entry
->mask_pos
= dev
->msi_cap
+ PCI_MSI_MASK_32
;
587 /* Save the initial mask status */
588 if (entry
->msi_attrib
.maskbit
)
589 pci_read_config_dword(dev
, entry
->mask_pos
, &entry
->masked
);
596 static int msi_verify_entries(struct pci_dev
*dev
)
598 struct msi_desc
*entry
;
600 for_each_pci_msi_entry(entry
, dev
) {
601 if (!dev
->no_64bit_msi
|| !entry
->msg
.address_hi
)
603 pci_err(dev
, "Device has broken 64-bit MSI but arch"
604 " tried to assign one above 4G\n");
611 * msi_capability_init - configure device's MSI capability structure
612 * @dev: pointer to the pci_dev data structure of MSI device function
613 * @nvec: number of interrupts to allocate
614 * @affd: description of automatic IRQ affinity assignments (may be %NULL)
616 * Setup the MSI capability structure of the device with the requested
617 * number of interrupts. A return value of zero indicates the successful
618 * setup of an entry with the new MSI IRQ. A negative return value indicates
619 * an error, and a positive return value indicates the number of interrupts
620 * which could have been allocated.
622 static int msi_capability_init(struct pci_dev
*dev
, int nvec
,
623 struct irq_affinity
*affd
)
625 struct msi_desc
*entry
;
629 pci_msi_set_enable(dev
, 0); /* Disable MSI during set up */
631 entry
= msi_setup_entry(dev
, nvec
, affd
);
635 /* All MSIs are unmasked by default; mask them all */
636 mask
= msi_mask(entry
->msi_attrib
.multi_cap
);
637 msi_mask_irq(entry
, mask
, mask
);
639 list_add_tail(&entry
->list
, dev_to_msi_list(&dev
->dev
));
641 /* Configure MSI capability structure */
642 ret
= pci_msi_setup_msi_irqs(dev
, nvec
, PCI_CAP_ID_MSI
);
644 msi_mask_irq(entry
, mask
, ~mask
);
649 ret
= msi_verify_entries(dev
);
651 msi_mask_irq(entry
, mask
, ~mask
);
656 ret
= populate_msi_sysfs(dev
);
658 msi_mask_irq(entry
, mask
, ~mask
);
663 /* Set MSI enabled bits */
664 pci_intx_for_msi(dev
, 0);
665 pci_msi_set_enable(dev
, 1);
666 dev
->msi_enabled
= 1;
668 pcibios_free_irq(dev
);
669 dev
->irq
= entry
->irq
;
673 static void __iomem
*msix_map_region(struct pci_dev
*dev
, unsigned nr_entries
)
675 resource_size_t phys_addr
;
680 pci_read_config_dword(dev
, dev
->msix_cap
+ PCI_MSIX_TABLE
,
682 bir
= (u8
)(table_offset
& PCI_MSIX_TABLE_BIR
);
683 flags
= pci_resource_flags(dev
, bir
);
684 if (!flags
|| (flags
& IORESOURCE_UNSET
))
687 table_offset
&= PCI_MSIX_TABLE_OFFSET
;
688 phys_addr
= pci_resource_start(dev
, bir
) + table_offset
;
690 return ioremap_nocache(phys_addr
, nr_entries
* PCI_MSIX_ENTRY_SIZE
);
693 static int msix_setup_entries(struct pci_dev
*dev
, void __iomem
*base
,
694 struct msix_entry
*entries
, int nvec
,
695 struct irq_affinity
*affd
)
697 struct irq_affinity_desc
*curmsk
, *masks
= NULL
;
698 struct msi_desc
*entry
;
700 int vec_count
= pci_msix_vec_count(dev
);
703 masks
= irq_create_affinity_masks(nvec
, affd
);
705 for (i
= 0, curmsk
= masks
; i
< nvec
; i
++) {
706 entry
= alloc_msi_entry(&dev
->dev
, 1, curmsk
);
712 /* No enough memory. Don't try again */
717 entry
->msi_attrib
.is_msix
= 1;
718 entry
->msi_attrib
.is_64
= 1;
720 entry
->msi_attrib
.entry_nr
= entries
[i
].entry
;
722 entry
->msi_attrib
.entry_nr
= i
;
724 entry
->msi_attrib
.is_virtual
=
725 entry
->msi_attrib
.entry_nr
>= vec_count
;
727 entry
->msi_attrib
.default_irq
= dev
->irq
;
728 entry
->mask_base
= base
;
730 list_add_tail(&entry
->list
, dev_to_msi_list(&dev
->dev
));
740 static void msix_program_entries(struct pci_dev
*dev
,
741 struct msix_entry
*entries
)
743 struct msi_desc
*entry
;
745 void __iomem
*desc_addr
;
747 for_each_pci_msi_entry(entry
, dev
) {
749 entries
[i
++].vector
= entry
->irq
;
751 desc_addr
= pci_msix_desc_addr(entry
);
753 entry
->masked
= readl(desc_addr
+
754 PCI_MSIX_ENTRY_VECTOR_CTRL
);
758 msix_mask_irq(entry
, 1);
763 * msix_capability_init - configure device's MSI-X capability
764 * @dev: pointer to the pci_dev data structure of MSI-X device function
765 * @entries: pointer to an array of struct msix_entry entries
766 * @nvec: number of @entries
767 * @affd: Optional pointer to enable automatic affinity assignment
769 * Setup the MSI-X capability structure of device function with a
770 * single MSI-X IRQ. A return of zero indicates the successful setup of
771 * requested MSI-X entries with allocated IRQs or non-zero for otherwise.
773 static int msix_capability_init(struct pci_dev
*dev
, struct msix_entry
*entries
,
774 int nvec
, struct irq_affinity
*affd
)
780 /* Ensure MSI-X is disabled while it is set up */
781 pci_msix_clear_and_set_ctrl(dev
, PCI_MSIX_FLAGS_ENABLE
, 0);
783 pci_read_config_word(dev
, dev
->msix_cap
+ PCI_MSIX_FLAGS
, &control
);
784 /* Request & Map MSI-X table region */
785 base
= msix_map_region(dev
, msix_table_size(control
));
789 ret
= msix_setup_entries(dev
, base
, entries
, nvec
, affd
);
793 ret
= pci_msi_setup_msi_irqs(dev
, nvec
, PCI_CAP_ID_MSIX
);
797 /* Check if all MSI entries honor device restrictions */
798 ret
= msi_verify_entries(dev
);
803 * Some devices require MSI-X to be enabled before we can touch the
804 * MSI-X registers. We need to mask all the vectors to prevent
805 * interrupts coming in before they're fully set up.
807 pci_msix_clear_and_set_ctrl(dev
, 0,
808 PCI_MSIX_FLAGS_MASKALL
| PCI_MSIX_FLAGS_ENABLE
);
810 msix_program_entries(dev
, entries
);
812 ret
= populate_msi_sysfs(dev
);
816 /* Set MSI-X enabled bits and unmask the function */
817 pci_intx_for_msi(dev
, 0);
818 dev
->msix_enabled
= 1;
819 pci_msix_clear_and_set_ctrl(dev
, PCI_MSIX_FLAGS_MASKALL
, 0);
821 pcibios_free_irq(dev
);
827 * If we had some success, report the number of IRQs
828 * we succeeded in setting up.
830 struct msi_desc
*entry
;
833 for_each_pci_msi_entry(entry
, dev
) {
848 * pci_msi_supported - check whether MSI may be enabled on a device
849 * @dev: pointer to the pci_dev data structure of MSI device function
850 * @nvec: how many MSIs have been requested?
852 * Look at global flags, the device itself, and its parent buses
853 * to determine if MSI/-X are supported for the device. If MSI/-X is
854 * supported return 1, else return 0.
856 static int pci_msi_supported(struct pci_dev
*dev
, int nvec
)
860 /* MSI must be globally enabled and supported by the device */
864 if (!dev
|| dev
->no_msi
|| dev
->current_state
!= PCI_D0
)
868 * You can't ask to have 0 or less MSIs configured.
870 * b) the list manipulation code assumes nvec >= 1.
876 * Any bridge which does NOT route MSI transactions from its
877 * secondary bus to its primary bus must set NO_MSI flag on
878 * the secondary pci_bus.
879 * We expect only arch-specific PCI host bus controller driver
880 * or quirks for specific PCI bridges to be setting NO_MSI.
882 for (bus
= dev
->bus
; bus
; bus
= bus
->parent
)
883 if (bus
->bus_flags
& PCI_BUS_FLAGS_NO_MSI
)
890 * pci_msi_vec_count - Return the number of MSI vectors a device can send
891 * @dev: device to report about
893 * This function returns the number of MSI vectors a device requested via
894 * Multiple Message Capable register. It returns a negative errno if the
895 * device is not capable sending MSI interrupts. Otherwise, the call succeeds
896 * and returns a power of two, up to a maximum of 2^5 (32), according to the
899 int pci_msi_vec_count(struct pci_dev
*dev
)
907 pci_read_config_word(dev
, dev
->msi_cap
+ PCI_MSI_FLAGS
, &msgctl
);
908 ret
= 1 << ((msgctl
& PCI_MSI_FLAGS_QMASK
) >> 1);
912 EXPORT_SYMBOL(pci_msi_vec_count
);
914 static void pci_msi_shutdown(struct pci_dev
*dev
)
916 struct msi_desc
*desc
;
919 if (!pci_msi_enable
|| !dev
|| !dev
->msi_enabled
)
922 BUG_ON(list_empty(dev_to_msi_list(&dev
->dev
)));
923 desc
= first_pci_msi_entry(dev
);
925 pci_msi_set_enable(dev
, 0);
926 pci_intx_for_msi(dev
, 1);
927 dev
->msi_enabled
= 0;
929 /* Return the device with MSI unmasked as initial states */
930 mask
= msi_mask(desc
->msi_attrib
.multi_cap
);
931 /* Keep cached state to be restored */
932 __pci_msi_desc_mask_irq(desc
, mask
, ~mask
);
934 /* Restore dev->irq to its default pin-assertion IRQ */
935 dev
->irq
= desc
->msi_attrib
.default_irq
;
936 pcibios_alloc_irq(dev
);
939 void pci_disable_msi(struct pci_dev
*dev
)
941 if (!pci_msi_enable
|| !dev
|| !dev
->msi_enabled
)
944 pci_msi_shutdown(dev
);
947 EXPORT_SYMBOL(pci_disable_msi
);
950 * pci_msix_vec_count - return the number of device's MSI-X table entries
951 * @dev: pointer to the pci_dev data structure of MSI-X device function
952 * This function returns the number of device's MSI-X table entries and
953 * therefore the number of MSI-X vectors device is capable of sending.
954 * It returns a negative errno if the device is not capable of sending MSI-X
957 int pci_msix_vec_count(struct pci_dev
*dev
)
964 pci_read_config_word(dev
, dev
->msix_cap
+ PCI_MSIX_FLAGS
, &control
);
965 return msix_table_size(control
);
967 EXPORT_SYMBOL(pci_msix_vec_count
);
969 static int __pci_enable_msix(struct pci_dev
*dev
, struct msix_entry
*entries
,
970 int nvec
, struct irq_affinity
*affd
, int flags
)
975 if (!pci_msi_supported(dev
, nvec
))
978 nr_entries
= pci_msix_vec_count(dev
);
981 if (nvec
> nr_entries
&& !(flags
& PCI_IRQ_VIRTUAL
))
985 /* Check for any invalid entries */
986 for (i
= 0; i
< nvec
; i
++) {
987 if (entries
[i
].entry
>= nr_entries
)
988 return -EINVAL
; /* invalid entry */
989 for (j
= i
+ 1; j
< nvec
; j
++) {
990 if (entries
[i
].entry
== entries
[j
].entry
)
991 return -EINVAL
; /* duplicate entry */
996 /* Check whether driver already requested for MSI IRQ */
997 if (dev
->msi_enabled
) {
998 pci_info(dev
, "can't enable MSI-X (MSI IRQ already assigned)\n");
1001 return msix_capability_init(dev
, entries
, nvec
, affd
);
1004 static void pci_msix_shutdown(struct pci_dev
*dev
)
1006 struct msi_desc
*entry
;
1008 if (!pci_msi_enable
|| !dev
|| !dev
->msix_enabled
)
1011 if (pci_dev_is_disconnected(dev
)) {
1012 dev
->msix_enabled
= 0;
1016 /* Return the device with MSI-X masked as initial states */
1017 for_each_pci_msi_entry(entry
, dev
) {
1018 /* Keep cached states to be restored */
1019 __pci_msix_desc_mask_irq(entry
, 1);
1022 pci_msix_clear_and_set_ctrl(dev
, PCI_MSIX_FLAGS_ENABLE
, 0);
1023 pci_intx_for_msi(dev
, 1);
1024 dev
->msix_enabled
= 0;
1025 pcibios_alloc_irq(dev
);
1028 void pci_disable_msix(struct pci_dev
*dev
)
1030 if (!pci_msi_enable
|| !dev
|| !dev
->msix_enabled
)
1033 pci_msix_shutdown(dev
);
1036 EXPORT_SYMBOL(pci_disable_msix
);
1038 void pci_no_msi(void)
1044 * pci_msi_enabled - is MSI enabled?
1046 * Returns true if MSI has not been disabled by the command-line option
1049 int pci_msi_enabled(void)
1051 return pci_msi_enable
;
1053 EXPORT_SYMBOL(pci_msi_enabled
);
1055 static int __pci_enable_msi_range(struct pci_dev
*dev
, int minvec
, int maxvec
,
1056 struct irq_affinity
*affd
)
1061 if (!pci_msi_supported(dev
, minvec
))
1064 /* Check whether driver already requested MSI-X IRQs */
1065 if (dev
->msix_enabled
) {
1066 pci_info(dev
, "can't enable MSI (MSI-X already enabled)\n");
1070 if (maxvec
< minvec
)
1073 if (WARN_ON_ONCE(dev
->msi_enabled
))
1076 nvec
= pci_msi_vec_count(dev
);
1087 nvec
= irq_calc_affinity_vectors(minvec
, nvec
, affd
);
1092 rc
= msi_capability_init(dev
, nvec
, affd
);
1105 /* deprecated, don't use */
1106 int pci_enable_msi(struct pci_dev
*dev
)
1108 int rc
= __pci_enable_msi_range(dev
, 1, 1, NULL
);
1113 EXPORT_SYMBOL(pci_enable_msi
);
1115 static int __pci_enable_msix_range(struct pci_dev
*dev
,
1116 struct msix_entry
*entries
, int minvec
,
1117 int maxvec
, struct irq_affinity
*affd
,
1120 int rc
, nvec
= maxvec
;
1122 if (maxvec
< minvec
)
1125 if (WARN_ON_ONCE(dev
->msix_enabled
))
1130 nvec
= irq_calc_affinity_vectors(minvec
, nvec
, affd
);
1135 rc
= __pci_enable_msix(dev
, entries
, nvec
, affd
, flags
);
1149 * pci_enable_msix_range - configure device's MSI-X capability structure
1150 * @dev: pointer to the pci_dev data structure of MSI-X device function
1151 * @entries: pointer to an array of MSI-X entries
1152 * @minvec: minimum number of MSI-X IRQs requested
1153 * @maxvec: maximum number of MSI-X IRQs requested
1155 * Setup the MSI-X capability structure of device function with a maximum
1156 * possible number of interrupts in the range between @minvec and @maxvec
1157 * upon its software driver call to request for MSI-X mode enabled on its
1158 * hardware device function. It returns a negative errno if an error occurs.
1159 * If it succeeds, it returns the actual number of interrupts allocated and
1160 * indicates the successful configuration of MSI-X capability structure
1161 * with new allocated MSI-X interrupts.
1163 int pci_enable_msix_range(struct pci_dev
*dev
, struct msix_entry
*entries
,
1164 int minvec
, int maxvec
)
1166 return __pci_enable_msix_range(dev
, entries
, minvec
, maxvec
, NULL
, 0);
1168 EXPORT_SYMBOL(pci_enable_msix_range
);
1171 * pci_alloc_irq_vectors_affinity - allocate multiple IRQs for a device
1172 * @dev: PCI device to operate on
1173 * @min_vecs: minimum number of vectors required (must be >= 1)
1174 * @max_vecs: maximum (desired) number of vectors
1175 * @flags: flags or quirks for the allocation
1176 * @affd: optional description of the affinity requirements
1178 * Allocate up to @max_vecs interrupt vectors for @dev, using MSI-X or MSI
1179 * vectors if available, and fall back to a single legacy vector
1180 * if neither is available. Return the number of vectors allocated,
1181 * (which might be smaller than @max_vecs) if successful, or a negative
1182 * error code on error. If less than @min_vecs interrupt vectors are
1183 * available for @dev the function will fail with -ENOSPC.
1185 * To get the Linux IRQ number used for a vector that can be passed to
1186 * request_irq() use the pci_irq_vector() helper.
1188 int pci_alloc_irq_vectors_affinity(struct pci_dev
*dev
, unsigned int min_vecs
,
1189 unsigned int max_vecs
, unsigned int flags
,
1190 struct irq_affinity
*affd
)
1192 struct irq_affinity msi_default_affd
= {0};
1193 int msix_vecs
= -ENOSPC
;
1194 int msi_vecs
= -ENOSPC
;
1196 if (flags
& PCI_IRQ_AFFINITY
) {
1198 affd
= &msi_default_affd
;
1204 if (flags
& PCI_IRQ_MSIX
) {
1205 msix_vecs
= __pci_enable_msix_range(dev
, NULL
, min_vecs
,
1206 max_vecs
, affd
, flags
);
1211 if (flags
& PCI_IRQ_MSI
) {
1212 msi_vecs
= __pci_enable_msi_range(dev
, min_vecs
, max_vecs
,
1218 /* use legacy IRQ if allowed */
1219 if (flags
& PCI_IRQ_LEGACY
) {
1220 if (min_vecs
== 1 && dev
->irq
) {
1222 * Invoke the affinity spreading logic to ensure that
1223 * the device driver can adjust queue configuration
1224 * for the single interrupt case.
1227 irq_create_affinity_masks(1, affd
);
1233 if (msix_vecs
== -ENOSPC
)
1237 EXPORT_SYMBOL(pci_alloc_irq_vectors_affinity
);
1240 * pci_free_irq_vectors - free previously allocated IRQs for a device
1241 * @dev: PCI device to operate on
1243 * Undoes the allocations and enabling in pci_alloc_irq_vectors().
1245 void pci_free_irq_vectors(struct pci_dev
*dev
)
1247 pci_disable_msix(dev
);
1248 pci_disable_msi(dev
);
1250 EXPORT_SYMBOL(pci_free_irq_vectors
);
1253 * pci_irq_vector - return Linux IRQ number of a device vector
1254 * @dev: PCI device to operate on
1255 * @nr: device-relative interrupt vector index (0-based).
1257 int pci_irq_vector(struct pci_dev
*dev
, unsigned int nr
)
1259 if (dev
->msix_enabled
) {
1260 struct msi_desc
*entry
;
1263 for_each_pci_msi_entry(entry
, dev
) {
1272 if (dev
->msi_enabled
) {
1273 struct msi_desc
*entry
= first_pci_msi_entry(dev
);
1275 if (WARN_ON_ONCE(nr
>= entry
->nvec_used
))
1278 if (WARN_ON_ONCE(nr
> 0))
1282 return dev
->irq
+ nr
;
1284 EXPORT_SYMBOL(pci_irq_vector
);
1287 * pci_irq_get_affinity - return the affinity of a particular MSI vector
1288 * @dev: PCI device to operate on
1289 * @nr: device-relative interrupt vector index (0-based).
1291 const struct cpumask
*pci_irq_get_affinity(struct pci_dev
*dev
, int nr
)
1293 if (dev
->msix_enabled
) {
1294 struct msi_desc
*entry
;
1297 for_each_pci_msi_entry(entry
, dev
) {
1299 return &entry
->affinity
->mask
;
1304 } else if (dev
->msi_enabled
) {
1305 struct msi_desc
*entry
= first_pci_msi_entry(dev
);
1307 if (WARN_ON_ONCE(!entry
|| !entry
->affinity
||
1308 nr
>= entry
->nvec_used
))
1311 return &entry
->affinity
[nr
].mask
;
1313 return cpu_possible_mask
;
1316 EXPORT_SYMBOL(pci_irq_get_affinity
);
1318 struct pci_dev
*msi_desc_to_pci_dev(struct msi_desc
*desc
)
1320 return to_pci_dev(desc
->dev
);
1322 EXPORT_SYMBOL(msi_desc_to_pci_dev
);
1324 void *msi_desc_to_pci_sysdata(struct msi_desc
*desc
)
1326 struct pci_dev
*dev
= msi_desc_to_pci_dev(desc
);
1328 return dev
->bus
->sysdata
;
1330 EXPORT_SYMBOL_GPL(msi_desc_to_pci_sysdata
);
1332 #ifdef CONFIG_PCI_MSI_IRQ_DOMAIN
1334 * pci_msi_domain_write_msg - Helper to write MSI message to PCI config space
1335 * @irq_data: Pointer to interrupt data of the MSI interrupt
1336 * @msg: Pointer to the message
1338 void pci_msi_domain_write_msg(struct irq_data
*irq_data
, struct msi_msg
*msg
)
1340 struct msi_desc
*desc
= irq_data_get_msi_desc(irq_data
);
1343 * For MSI-X desc->irq is always equal to irq_data->irq. For
1344 * MSI only the first interrupt of MULTI MSI passes the test.
1346 if (desc
->irq
== irq_data
->irq
)
1347 __pci_write_msi_msg(desc
, msg
);
1351 * pci_msi_domain_calc_hwirq - Generate a unique ID for an MSI source
1352 * @dev: Pointer to the PCI device
1353 * @desc: Pointer to the MSI descriptor
1355 * The ID number is only used within the irqdomain.
1357 irq_hw_number_t
pci_msi_domain_calc_hwirq(struct pci_dev
*dev
,
1358 struct msi_desc
*desc
)
1360 return (irq_hw_number_t
)desc
->msi_attrib
.entry_nr
|
1361 pci_dev_id(dev
) << 11 |
1362 (pci_domain_nr(dev
->bus
) & 0xFFFFFFFF) << 27;
1365 static inline bool pci_msi_desc_is_multi_msi(struct msi_desc
*desc
)
1367 return !desc
->msi_attrib
.is_msix
&& desc
->nvec_used
> 1;
1371 * pci_msi_domain_check_cap - Verify that @domain supports the capabilities
1373 * @domain: The interrupt domain to check
1374 * @info: The domain info for verification
1375 * @dev: The device to check
1378 * 0 if the functionality is supported
1379 * 1 if Multi MSI is requested, but the domain does not support it
1380 * -ENOTSUPP otherwise
1382 int pci_msi_domain_check_cap(struct irq_domain
*domain
,
1383 struct msi_domain_info
*info
, struct device
*dev
)
1385 struct msi_desc
*desc
= first_pci_msi_entry(to_pci_dev(dev
));
1387 /* Special handling to support __pci_enable_msi_range() */
1388 if (pci_msi_desc_is_multi_msi(desc
) &&
1389 !(info
->flags
& MSI_FLAG_MULTI_PCI_MSI
))
1391 else if (desc
->msi_attrib
.is_msix
&& !(info
->flags
& MSI_FLAG_PCI_MSIX
))
1397 static int pci_msi_domain_handle_error(struct irq_domain
*domain
,
1398 struct msi_desc
*desc
, int error
)
1400 /* Special handling to support __pci_enable_msi_range() */
1401 if (pci_msi_desc_is_multi_msi(desc
) && error
== -ENOSPC
)
1407 #ifdef GENERIC_MSI_DOMAIN_OPS
1408 static void pci_msi_domain_set_desc(msi_alloc_info_t
*arg
,
1409 struct msi_desc
*desc
)
1412 arg
->hwirq
= pci_msi_domain_calc_hwirq(msi_desc_to_pci_dev(desc
),
1416 #define pci_msi_domain_set_desc NULL
1419 static struct msi_domain_ops pci_msi_domain_ops_default
= {
1420 .set_desc
= pci_msi_domain_set_desc
,
1421 .msi_check
= pci_msi_domain_check_cap
,
1422 .handle_error
= pci_msi_domain_handle_error
,
1425 static void pci_msi_domain_update_dom_ops(struct msi_domain_info
*info
)
1427 struct msi_domain_ops
*ops
= info
->ops
;
1430 info
->ops
= &pci_msi_domain_ops_default
;
1432 if (ops
->set_desc
== NULL
)
1433 ops
->set_desc
= pci_msi_domain_set_desc
;
1434 if (ops
->msi_check
== NULL
)
1435 ops
->msi_check
= pci_msi_domain_check_cap
;
1436 if (ops
->handle_error
== NULL
)
1437 ops
->handle_error
= pci_msi_domain_handle_error
;
1441 static void pci_msi_domain_update_chip_ops(struct msi_domain_info
*info
)
1443 struct irq_chip
*chip
= info
->chip
;
1446 if (!chip
->irq_write_msi_msg
)
1447 chip
->irq_write_msi_msg
= pci_msi_domain_write_msg
;
1448 if (!chip
->irq_mask
)
1449 chip
->irq_mask
= pci_msi_mask_irq
;
1450 if (!chip
->irq_unmask
)
1451 chip
->irq_unmask
= pci_msi_unmask_irq
;
1455 * pci_msi_create_irq_domain - Create a MSI interrupt domain
1456 * @fwnode: Optional fwnode of the interrupt controller
1457 * @info: MSI domain info
1458 * @parent: Parent irq domain
1460 * Updates the domain and chip ops and creates a MSI interrupt domain.
1463 * A domain pointer or NULL in case of failure.
1465 struct irq_domain
*pci_msi_create_irq_domain(struct fwnode_handle
*fwnode
,
1466 struct msi_domain_info
*info
,
1467 struct irq_domain
*parent
)
1469 struct irq_domain
*domain
;
1471 if (WARN_ON(info
->flags
& MSI_FLAG_LEVEL_CAPABLE
))
1472 info
->flags
&= ~MSI_FLAG_LEVEL_CAPABLE
;
1474 if (info
->flags
& MSI_FLAG_USE_DEF_DOM_OPS
)
1475 pci_msi_domain_update_dom_ops(info
);
1476 if (info
->flags
& MSI_FLAG_USE_DEF_CHIP_OPS
)
1477 pci_msi_domain_update_chip_ops(info
);
1479 info
->flags
|= MSI_FLAG_ACTIVATE_EARLY
;
1480 if (IS_ENABLED(CONFIG_GENERIC_IRQ_RESERVATION_MODE
))
1481 info
->flags
|= MSI_FLAG_MUST_REACTIVATE
;
1483 /* PCI-MSI is oneshot-safe */
1484 info
->chip
->flags
|= IRQCHIP_ONESHOT_SAFE
;
1486 domain
= msi_create_irq_domain(fwnode
, info
, parent
);
1490 irq_domain_update_bus_token(domain
, DOMAIN_BUS_PCI_MSI
);
1493 EXPORT_SYMBOL_GPL(pci_msi_create_irq_domain
);
1496 * Users of the generic MSI infrastructure expect a device to have a single ID,
1497 * so with DMA aliases we have to pick the least-worst compromise. Devices with
1498 * DMA phantom functions tend to still emit MSIs from the real function number,
1499 * so we ignore those and only consider topological aliases where either the
1500 * alias device or RID appears on a different bus number. We also make the
1501 * reasonable assumption that bridges are walked in an upstream direction (so
1502 * the last one seen wins), and the much braver assumption that the most likely
1503 * case is that of PCI->PCIe so we should always use the alias RID. This echoes
1504 * the logic from intel_irq_remapping's set_msi_sid(), which presumably works
1505 * well enough in practice; in the face of the horrible PCIe<->PCI-X conditions
1506 * for taking ownership all we can really do is close our eyes and hope...
1508 static int get_msi_id_cb(struct pci_dev
*pdev
, u16 alias
, void *data
)
1511 u8 bus
= PCI_BUS_NUM(*pa
);
1513 if (pdev
->bus
->number
!= bus
|| PCI_BUS_NUM(alias
) != bus
)
1520 * pci_msi_domain_get_msi_rid - Get the MSI requester id (RID)
1521 * @domain: The interrupt domain
1522 * @pdev: The PCI device.
1524 * The RID for a device is formed from the alias, with a firmware
1525 * supplied mapping applied
1529 u32
pci_msi_domain_get_msi_rid(struct irq_domain
*domain
, struct pci_dev
*pdev
)
1531 struct device_node
*of_node
;
1532 u32 rid
= pci_dev_id(pdev
);
1534 pci_for_each_dma_alias(pdev
, get_msi_id_cb
, &rid
);
1536 of_node
= irq_domain_get_of_node(domain
);
1537 rid
= of_node
? of_msi_map_rid(&pdev
->dev
, of_node
, rid
) :
1538 iort_msi_map_rid(&pdev
->dev
, rid
);
1544 * pci_msi_get_device_domain - Get the MSI domain for a given PCI device
1545 * @pdev: The PCI device
1547 * Use the firmware data to find a device-specific MSI domain
1548 * (i.e. not one that is set as a default).
1550 * Returns: The corresponding MSI domain or NULL if none has been found.
1552 struct irq_domain
*pci_msi_get_device_domain(struct pci_dev
*pdev
)
1554 struct irq_domain
*dom
;
1555 u32 rid
= pci_dev_id(pdev
);
1557 pci_for_each_dma_alias(pdev
, get_msi_id_cb
, &rid
);
1558 dom
= of_msi_map_get_device_domain(&pdev
->dev
, rid
);
1560 dom
= iort_get_device_domain(&pdev
->dev
, rid
);
1563 #endif /* CONFIG_PCI_MSI_IRQ_DOMAIN */