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-rw-r--r--drivers/pci/msi.c1151
1 files changed, 1151 insertions, 0 deletions
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
new file mode 100644
index 000000000000..22ecd3b058be
--- /dev/null
+++ b/drivers/pci/msi.c
@@ -0,0 +1,1151 @@
1/*
2 * File: msi.c
3 * Purpose: PCI Message Signaled Interrupt (MSI)
4 *
5 * Copyright (C) 2003-2004 Intel
6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
7 */
8
9#include <linux/mm.h>
10#include <linux/irq.h>
11#include <linux/interrupt.h>
12#include <linux/init.h>
13#include <linux/config.h>
14#include <linux/ioport.h>
15#include <linux/smp_lock.h>
16#include <linux/pci.h>
17#include <linux/proc_fs.h>
18
19#include <asm/errno.h>
20#include <asm/io.h>
21#include <asm/smp.h>
22
23#include "pci.h"
24#include "msi.h"
25
26static DEFINE_SPINLOCK(msi_lock);
27static struct msi_desc* msi_desc[NR_IRQS] = { [0 ... NR_IRQS-1] = NULL };
28static kmem_cache_t* msi_cachep;
29
30static int pci_msi_enable = 1;
31static int last_alloc_vector = 0;
32static int nr_released_vectors = 0;
33static int nr_reserved_vectors = NR_HP_RESERVED_VECTORS;
34static int nr_msix_devices = 0;
35
36#ifndef CONFIG_X86_IO_APIC
37int vector_irq[NR_VECTORS] = { [0 ... NR_VECTORS - 1] = -1};
38u8 irq_vector[NR_IRQ_VECTORS] = { FIRST_DEVICE_VECTOR , 0 };
39#endif
40
41static void msi_cache_ctor(void *p, kmem_cache_t *cache, unsigned long flags)
42{
43 memset(p, 0, NR_IRQS * sizeof(struct msi_desc));
44}
45
46static int msi_cache_init(void)
47{
48 msi_cachep = kmem_cache_create("msi_cache",
49 NR_IRQS * sizeof(struct msi_desc),
50 0, SLAB_HWCACHE_ALIGN, msi_cache_ctor, NULL);
51 if (!msi_cachep)
52 return -ENOMEM;
53
54 return 0;
55}
56
57static void msi_set_mask_bit(unsigned int vector, int flag)
58{
59 struct msi_desc *entry;
60
61 entry = (struct msi_desc *)msi_desc[vector];
62 if (!entry || !entry->dev || !entry->mask_base)
63 return;
64 switch (entry->msi_attrib.type) {
65 case PCI_CAP_ID_MSI:
66 {
67 int pos;
68 u32 mask_bits;
69
70 pos = (long)entry->mask_base;
71 pci_read_config_dword(entry->dev, pos, &mask_bits);
72 mask_bits &= ~(1);
73 mask_bits |= flag;
74 pci_write_config_dword(entry->dev, pos, mask_bits);
75 break;
76 }
77 case PCI_CAP_ID_MSIX:
78 {
79 int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
80 PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET;
81 writel(flag, entry->mask_base + offset);
82 break;
83 }
84 default:
85 break;
86 }
87}
88
89#ifdef CONFIG_SMP
90static void set_msi_affinity(unsigned int vector, cpumask_t cpu_mask)
91{
92 struct msi_desc *entry;
93 struct msg_address address;
94
95 entry = (struct msi_desc *)msi_desc[vector];
96 if (!entry || !entry->dev)
97 return;
98
99 switch (entry->msi_attrib.type) {
100 case PCI_CAP_ID_MSI:
101 {
102 int pos;
103
104 if (!(pos = pci_find_capability(entry->dev, PCI_CAP_ID_MSI)))
105 return;
106
107 pci_read_config_dword(entry->dev, msi_lower_address_reg(pos),
108 &address.lo_address.value);
109 address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
110 address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
111 MSI_TARGET_CPU_SHIFT);
112 entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
113 pci_write_config_dword(entry->dev, msi_lower_address_reg(pos),
114 address.lo_address.value);
115 break;
116 }
117 case PCI_CAP_ID_MSIX:
118 {
119 int offset = entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE +
120 PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET;
121
122 address.lo_address.value = readl(entry->mask_base + offset);
123 address.lo_address.value &= MSI_ADDRESS_DEST_ID_MASK;
124 address.lo_address.value |= (cpu_mask_to_apicid(cpu_mask) <<
125 MSI_TARGET_CPU_SHIFT);
126 entry->msi_attrib.current_cpu = cpu_mask_to_apicid(cpu_mask);
127 writel(address.lo_address.value, entry->mask_base + offset);
128 break;
129 }
130 default:
131 break;
132 }
133}
134
135#ifdef CONFIG_IRQBALANCE
136static inline void move_msi(int vector)
137{
138 if (!cpus_empty(pending_irq_balance_cpumask[vector])) {
139 set_msi_affinity(vector, pending_irq_balance_cpumask[vector]);
140 cpus_clear(pending_irq_balance_cpumask[vector]);
141 }
142}
143#endif /* CONFIG_IRQBALANCE */
144#endif /* CONFIG_SMP */
145
146static void mask_MSI_irq(unsigned int vector)
147{
148 msi_set_mask_bit(vector, 1);
149}
150
151static void unmask_MSI_irq(unsigned int vector)
152{
153 msi_set_mask_bit(vector, 0);
154}
155
156static unsigned int startup_msi_irq_wo_maskbit(unsigned int vector)
157{
158 struct msi_desc *entry;
159 unsigned long flags;
160
161 spin_lock_irqsave(&msi_lock, flags);
162 entry = msi_desc[vector];
163 if (!entry || !entry->dev) {
164 spin_unlock_irqrestore(&msi_lock, flags);
165 return 0;
166 }
167 entry->msi_attrib.state = 1; /* Mark it active */
168 spin_unlock_irqrestore(&msi_lock, flags);
169
170 return 0; /* never anything pending */
171}
172
173static void release_msi(unsigned int vector);
174static void shutdown_msi_irq(unsigned int vector)
175{
176 release_msi(vector);
177}
178
179#define shutdown_msi_irq_wo_maskbit shutdown_msi_irq
180static void enable_msi_irq_wo_maskbit(unsigned int vector) {}
181static void disable_msi_irq_wo_maskbit(unsigned int vector) {}
182static void ack_msi_irq_wo_maskbit(unsigned int vector) {}
183static void end_msi_irq_wo_maskbit(unsigned int vector)
184{
185 move_msi(vector);
186 ack_APIC_irq();
187}
188
189static unsigned int startup_msi_irq_w_maskbit(unsigned int vector)
190{
191 struct msi_desc *entry;
192 unsigned long flags;
193
194 spin_lock_irqsave(&msi_lock, flags);
195 entry = msi_desc[vector];
196 if (!entry || !entry->dev) {
197 spin_unlock_irqrestore(&msi_lock, flags);
198 return 0;
199 }
200 entry->msi_attrib.state = 1; /* Mark it active */
201 spin_unlock_irqrestore(&msi_lock, flags);
202
203 unmask_MSI_irq(vector);
204 return 0; /* never anything pending */
205}
206
207#define shutdown_msi_irq_w_maskbit shutdown_msi_irq
208#define enable_msi_irq_w_maskbit unmask_MSI_irq
209#define disable_msi_irq_w_maskbit mask_MSI_irq
210#define ack_msi_irq_w_maskbit mask_MSI_irq
211
212static void end_msi_irq_w_maskbit(unsigned int vector)
213{
214 move_msi(vector);
215 unmask_MSI_irq(vector);
216 ack_APIC_irq();
217}
218
219/*
220 * Interrupt Type for MSI-X PCI/PCI-X/PCI-Express Devices,
221 * which implement the MSI-X Capability Structure.
222 */
223static struct hw_interrupt_type msix_irq_type = {
224 .typename = "PCI-MSI-X",
225 .startup = startup_msi_irq_w_maskbit,
226 .shutdown = shutdown_msi_irq_w_maskbit,
227 .enable = enable_msi_irq_w_maskbit,
228 .disable = disable_msi_irq_w_maskbit,
229 .ack = ack_msi_irq_w_maskbit,
230 .end = end_msi_irq_w_maskbit,
231 .set_affinity = set_msi_irq_affinity
232};
233
234/*
235 * Interrupt Type for MSI PCI/PCI-X/PCI-Express Devices,
236 * which implement the MSI Capability Structure with
237 * Mask-and-Pending Bits.
238 */
239static struct hw_interrupt_type msi_irq_w_maskbit_type = {
240 .typename = "PCI-MSI",
241 .startup = startup_msi_irq_w_maskbit,
242 .shutdown = shutdown_msi_irq_w_maskbit,
243 .enable = enable_msi_irq_w_maskbit,
244 .disable = disable_msi_irq_w_maskbit,
245 .ack = ack_msi_irq_w_maskbit,
246 .end = end_msi_irq_w_maskbit,
247 .set_affinity = set_msi_irq_affinity
248};
249
250/*
251 * Interrupt Type for MSI PCI/PCI-X/PCI-Express Devices,
252 * which implement the MSI Capability Structure without
253 * Mask-and-Pending Bits.
254 */
255static struct hw_interrupt_type msi_irq_wo_maskbit_type = {
256 .typename = "PCI-MSI",
257 .startup = startup_msi_irq_wo_maskbit,
258 .shutdown = shutdown_msi_irq_wo_maskbit,
259 .enable = enable_msi_irq_wo_maskbit,
260 .disable = disable_msi_irq_wo_maskbit,
261 .ack = ack_msi_irq_wo_maskbit,
262 .end = end_msi_irq_wo_maskbit,
263 .set_affinity = set_msi_irq_affinity
264};
265
266static void msi_data_init(struct msg_data *msi_data,
267 unsigned int vector)
268{
269 memset(msi_data, 0, sizeof(struct msg_data));
270 msi_data->vector = (u8)vector;
271 msi_data->delivery_mode = MSI_DELIVERY_MODE;
272 msi_data->level = MSI_LEVEL_MODE;
273 msi_data->trigger = MSI_TRIGGER_MODE;
274}
275
276static void msi_address_init(struct msg_address *msi_address)
277{
278 unsigned int dest_id;
279
280 memset(msi_address, 0, sizeof(struct msg_address));
281 msi_address->hi_address = (u32)0;
282 dest_id = (MSI_ADDRESS_HEADER << MSI_ADDRESS_HEADER_SHIFT);
283 msi_address->lo_address.u.dest_mode = MSI_DEST_MODE;
284 msi_address->lo_address.u.redirection_hint = MSI_REDIRECTION_HINT_MODE;
285 msi_address->lo_address.u.dest_id = dest_id;
286 msi_address->lo_address.value |= (MSI_TARGET_CPU << MSI_TARGET_CPU_SHIFT);
287}
288
289static int msi_free_vector(struct pci_dev* dev, int vector, int reassign);
290static int assign_msi_vector(void)
291{
292 static int new_vector_avail = 1;
293 int vector;
294 unsigned long flags;
295
296 /*
297 * msi_lock is provided to ensure that successful allocation of MSI
298 * vector is assigned unique among drivers.
299 */
300 spin_lock_irqsave(&msi_lock, flags);
301
302 if (!new_vector_avail) {
303 int free_vector = 0;
304
305 /*
306 * vector_irq[] = -1 indicates that this specific vector is:
307 * - assigned for MSI (since MSI have no associated IRQ) or
308 * - assigned for legacy if less than 16, or
309 * - having no corresponding 1:1 vector-to-IOxAPIC IRQ mapping
310 * vector_irq[] = 0 indicates that this vector, previously
311 * assigned for MSI, is freed by hotplug removed operations.
312 * This vector will be reused for any subsequent hotplug added
313 * operations.
314 * vector_irq[] > 0 indicates that this vector is assigned for
315 * IOxAPIC IRQs. This vector and its value provides a 1-to-1
316 * vector-to-IOxAPIC IRQ mapping.
317 */
318 for (vector = FIRST_DEVICE_VECTOR; vector < NR_IRQS; vector++) {
319 if (vector_irq[vector] != 0)
320 continue;
321 free_vector = vector;
322 if (!msi_desc[vector])
323 break;
324 else
325 continue;
326 }
327 if (!free_vector) {
328 spin_unlock_irqrestore(&msi_lock, flags);
329 return -EBUSY;
330 }
331 vector_irq[free_vector] = -1;
332 nr_released_vectors--;
333 spin_unlock_irqrestore(&msi_lock, flags);
334 if (msi_desc[free_vector] != NULL) {
335 struct pci_dev *dev;
336 int tail;
337
338 /* free all linked vectors before re-assign */
339 do {
340 spin_lock_irqsave(&msi_lock, flags);
341 dev = msi_desc[free_vector]->dev;
342 tail = msi_desc[free_vector]->link.tail;
343 spin_unlock_irqrestore(&msi_lock, flags);
344 msi_free_vector(dev, tail, 1);
345 } while (free_vector != tail);
346 }
347
348 return free_vector;
349 }
350 vector = assign_irq_vector(AUTO_ASSIGN);
351 last_alloc_vector = vector;
352 if (vector == LAST_DEVICE_VECTOR)
353 new_vector_avail = 0;
354
355 spin_unlock_irqrestore(&msi_lock, flags);
356 return vector;
357}
358
359static int get_new_vector(void)
360{
361 int vector;
362
363 if ((vector = assign_msi_vector()) > 0)
364 set_intr_gate(vector, interrupt[vector]);
365
366 return vector;
367}
368
369static int msi_init(void)
370{
371 static int status = -ENOMEM;
372
373 if (!status)
374 return status;
375
376 if (pci_msi_quirk) {
377 pci_msi_enable = 0;
378 printk(KERN_WARNING "PCI: MSI quirk detected. MSI disabled.\n");
379 status = -EINVAL;
380 return status;
381 }
382
383 if ((status = msi_cache_init()) < 0) {
384 pci_msi_enable = 0;
385 printk(KERN_WARNING "PCI: MSI cache init failed\n");
386 return status;
387 }
388 last_alloc_vector = assign_irq_vector(AUTO_ASSIGN);
389 if (last_alloc_vector < 0) {
390 pci_msi_enable = 0;
391 printk(KERN_WARNING "PCI: No interrupt vectors available for MSI\n");
392 status = -EBUSY;
393 return status;
394 }
395 vector_irq[last_alloc_vector] = 0;
396 nr_released_vectors++;
397
398 return status;
399}
400
401static int get_msi_vector(struct pci_dev *dev)
402{
403 return get_new_vector();
404}
405
406static struct msi_desc* alloc_msi_entry(void)
407{
408 struct msi_desc *entry;
409
410 entry = (struct msi_desc*) kmem_cache_alloc(msi_cachep, SLAB_KERNEL);
411 if (!entry)
412 return NULL;
413
414 memset(entry, 0, sizeof(struct msi_desc));
415 entry->link.tail = entry->link.head = 0; /* single message */
416 entry->dev = NULL;
417
418 return entry;
419}
420
421static void attach_msi_entry(struct msi_desc *entry, int vector)
422{
423 unsigned long flags;
424
425 spin_lock_irqsave(&msi_lock, flags);
426 msi_desc[vector] = entry;
427 spin_unlock_irqrestore(&msi_lock, flags);
428}
429
430static void irq_handler_init(int cap_id, int pos, int mask)
431{
432 spin_lock(&irq_desc[pos].lock);
433 if (cap_id == PCI_CAP_ID_MSIX)
434 irq_desc[pos].handler = &msix_irq_type;
435 else {
436 if (!mask)
437 irq_desc[pos].handler = &msi_irq_wo_maskbit_type;
438 else
439 irq_desc[pos].handler = &msi_irq_w_maskbit_type;
440 }
441 spin_unlock(&irq_desc[pos].lock);
442}
443
444static void enable_msi_mode(struct pci_dev *dev, int pos, int type)
445{
446 u16 control;
447
448 pci_read_config_word(dev, msi_control_reg(pos), &control);
449 if (type == PCI_CAP_ID_MSI) {
450 /* Set enabled bits to single MSI & enable MSI_enable bit */
451 msi_enable(control, 1);
452 pci_write_config_word(dev, msi_control_reg(pos), control);
453 } else {
454 msix_enable(control);
455 pci_write_config_word(dev, msi_control_reg(pos), control);
456 }
457 if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
458 /* PCI Express Endpoint device detected */
459 u16 cmd;
460 pci_read_config_word(dev, PCI_COMMAND, &cmd);
461 cmd |= PCI_COMMAND_INTX_DISABLE;
462 pci_write_config_word(dev, PCI_COMMAND, cmd);
463 }
464}
465
466static void disable_msi_mode(struct pci_dev *dev, int pos, int type)
467{
468 u16 control;
469
470 pci_read_config_word(dev, msi_control_reg(pos), &control);
471 if (type == PCI_CAP_ID_MSI) {
472 /* Set enabled bits to single MSI & enable MSI_enable bit */
473 msi_disable(control);
474 pci_write_config_word(dev, msi_control_reg(pos), control);
475 } else {
476 msix_disable(control);
477 pci_write_config_word(dev, msi_control_reg(pos), control);
478 }
479 if (pci_find_capability(dev, PCI_CAP_ID_EXP)) {
480 /* PCI Express Endpoint device detected */
481 u16 cmd;
482 pci_read_config_word(dev, PCI_COMMAND, &cmd);
483 cmd &= ~PCI_COMMAND_INTX_DISABLE;
484 pci_write_config_word(dev, PCI_COMMAND, cmd);
485 }
486}
487
488static int msi_lookup_vector(struct pci_dev *dev, int type)
489{
490 int vector;
491 unsigned long flags;
492
493 spin_lock_irqsave(&msi_lock, flags);
494 for (vector = FIRST_DEVICE_VECTOR; vector < NR_IRQS; vector++) {
495 if (!msi_desc[vector] || msi_desc[vector]->dev != dev ||
496 msi_desc[vector]->msi_attrib.type != type ||
497 msi_desc[vector]->msi_attrib.default_vector != dev->irq)
498 continue;
499 spin_unlock_irqrestore(&msi_lock, flags);
500 /* This pre-assigned MSI vector for this device
501 already exits. Override dev->irq with this vector */
502 dev->irq = vector;
503 return 0;
504 }
505 spin_unlock_irqrestore(&msi_lock, flags);
506
507 return -EACCES;
508}
509
510void pci_scan_msi_device(struct pci_dev *dev)
511{
512 if (!dev)
513 return;
514
515 if (pci_find_capability(dev, PCI_CAP_ID_MSIX) > 0)
516 nr_msix_devices++;
517 else if (pci_find_capability(dev, PCI_CAP_ID_MSI) > 0)
518 nr_reserved_vectors++;
519}
520
521/**
522 * msi_capability_init - configure device's MSI capability structure
523 * @dev: pointer to the pci_dev data structure of MSI device function
524 *
525 * Setup the MSI capability structure of device funtion with a single
526 * MSI vector, regardless of device function is capable of handling
527 * multiple messages. A return of zero indicates the successful setup
528 * of an entry zero with the new MSI vector or non-zero for otherwise.
529 **/
530static int msi_capability_init(struct pci_dev *dev)
531{
532 struct msi_desc *entry;
533 struct msg_address address;
534 struct msg_data data;
535 int pos, vector;
536 u16 control;
537
538 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
539 pci_read_config_word(dev, msi_control_reg(pos), &control);
540 /* MSI Entry Initialization */
541 if (!(entry = alloc_msi_entry()))
542 return -ENOMEM;
543
544 if ((vector = get_msi_vector(dev)) < 0) {
545 kmem_cache_free(msi_cachep, entry);
546 return -EBUSY;
547 }
548 entry->link.head = vector;
549 entry->link.tail = vector;
550 entry->msi_attrib.type = PCI_CAP_ID_MSI;
551 entry->msi_attrib.state = 0; /* Mark it not active */
552 entry->msi_attrib.entry_nr = 0;
553 entry->msi_attrib.maskbit = is_mask_bit_support(control);
554 entry->msi_attrib.default_vector = dev->irq; /* Save IOAPIC IRQ */
555 dev->irq = vector;
556 entry->dev = dev;
557 if (is_mask_bit_support(control)) {
558 entry->mask_base = (void __iomem *)(long)msi_mask_bits_reg(pos,
559 is_64bit_address(control));
560 }
561 /* Replace with MSI handler */
562 irq_handler_init(PCI_CAP_ID_MSI, vector, entry->msi_attrib.maskbit);
563 /* Configure MSI capability structure */
564 msi_address_init(&address);
565 msi_data_init(&data, vector);
566 entry->msi_attrib.current_cpu = ((address.lo_address.u.dest_id >>
567 MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
568 pci_write_config_dword(dev, msi_lower_address_reg(pos),
569 address.lo_address.value);
570 if (is_64bit_address(control)) {
571 pci_write_config_dword(dev,
572 msi_upper_address_reg(pos), address.hi_address);
573 pci_write_config_word(dev,
574 msi_data_reg(pos, 1), *((u32*)&data));
575 } else
576 pci_write_config_word(dev,
577 msi_data_reg(pos, 0), *((u32*)&data));
578 if (entry->msi_attrib.maskbit) {
579 unsigned int maskbits, temp;
580 /* All MSIs are unmasked by default, Mask them all */
581 pci_read_config_dword(dev,
582 msi_mask_bits_reg(pos, is_64bit_address(control)),
583 &maskbits);
584 temp = (1 << multi_msi_capable(control));
585 temp = ((temp - 1) & ~temp);
586 maskbits |= temp;
587 pci_write_config_dword(dev,
588 msi_mask_bits_reg(pos, is_64bit_address(control)),
589 maskbits);
590 }
591 attach_msi_entry(entry, vector);
592 /* Set MSI enabled bits */
593 enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
594
595 return 0;
596}
597
598/**
599 * msix_capability_init - configure device's MSI-X capability
600 * @dev: pointer to the pci_dev data structure of MSI-X device function
601 *
602 * Setup the MSI-X capability structure of device funtion with a
603 * single MSI-X vector. A return of zero indicates the successful setup of
604 * requested MSI-X entries with allocated vectors or non-zero for otherwise.
605 **/
606static int msix_capability_init(struct pci_dev *dev,
607 struct msix_entry *entries, int nvec)
608{
609 struct msi_desc *head = NULL, *tail = NULL, *entry = NULL;
610 struct msg_address address;
611 struct msg_data data;
612 int vector, pos, i, j, nr_entries, temp = 0;
613 u32 phys_addr, table_offset;
614 u16 control;
615 u8 bir;
616 void __iomem *base;
617
618 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
619 /* Request & Map MSI-X table region */
620 pci_read_config_word(dev, msi_control_reg(pos), &control);
621 nr_entries = multi_msix_capable(control);
622 pci_read_config_dword(dev, msix_table_offset_reg(pos),
623 &table_offset);
624 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
625 phys_addr = pci_resource_start (dev, bir);
626 phys_addr += (u32)(table_offset & ~PCI_MSIX_FLAGS_BIRMASK);
627 base = ioremap_nocache(phys_addr, nr_entries * PCI_MSIX_ENTRY_SIZE);
628 if (base == NULL)
629 return -ENOMEM;
630
631 /* MSI-X Table Initialization */
632 for (i = 0; i < nvec; i++) {
633 entry = alloc_msi_entry();
634 if (!entry)
635 break;
636 if ((vector = get_msi_vector(dev)) < 0)
637 break;
638
639 j = entries[i].entry;
640 entries[i].vector = vector;
641 entry->msi_attrib.type = PCI_CAP_ID_MSIX;
642 entry->msi_attrib.state = 0; /* Mark it not active */
643 entry->msi_attrib.entry_nr = j;
644 entry->msi_attrib.maskbit = 1;
645 entry->msi_attrib.default_vector = dev->irq;
646 entry->dev = dev;
647 entry->mask_base = base;
648 if (!head) {
649 entry->link.head = vector;
650 entry->link.tail = vector;
651 head = entry;
652 } else {
653 entry->link.head = temp;
654 entry->link.tail = tail->link.tail;
655 tail->link.tail = vector;
656 head->link.head = vector;
657 }
658 temp = vector;
659 tail = entry;
660 /* Replace with MSI-X handler */
661 irq_handler_init(PCI_CAP_ID_MSIX, vector, 1);
662 /* Configure MSI-X capability structure */
663 msi_address_init(&address);
664 msi_data_init(&data, vector);
665 entry->msi_attrib.current_cpu =
666 ((address.lo_address.u.dest_id >>
667 MSI_TARGET_CPU_SHIFT) & MSI_TARGET_CPU_MASK);
668 writel(address.lo_address.value,
669 base + j * PCI_MSIX_ENTRY_SIZE +
670 PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
671 writel(address.hi_address,
672 base + j * PCI_MSIX_ENTRY_SIZE +
673 PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
674 writel(*(u32*)&data,
675 base + j * PCI_MSIX_ENTRY_SIZE +
676 PCI_MSIX_ENTRY_DATA_OFFSET);
677 attach_msi_entry(entry, vector);
678 }
679 if (i != nvec) {
680 i--;
681 for (; i >= 0; i--) {
682 vector = (entries + i)->vector;
683 msi_free_vector(dev, vector, 0);
684 (entries + i)->vector = 0;
685 }
686 return -EBUSY;
687 }
688 /* Set MSI-X enabled bits */
689 enable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
690
691 return 0;
692}
693
694/**
695 * pci_enable_msi - configure device's MSI capability structure
696 * @dev: pointer to the pci_dev data structure of MSI device function
697 *
698 * Setup the MSI capability structure of device function with
699 * a single MSI vector upon its software driver call to request for
700 * MSI mode enabled on its hardware device function. A return of zero
701 * indicates the successful setup of an entry zero with the new MSI
702 * vector or non-zero for otherwise.
703 **/
704int pci_enable_msi(struct pci_dev* dev)
705{
706 int pos, temp, status = -EINVAL;
707 u16 control;
708
709 if (!pci_msi_enable || !dev)
710 return status;
711
712 temp = dev->irq;
713
714 if ((status = msi_init()) < 0)
715 return status;
716
717 if (!(pos = pci_find_capability(dev, PCI_CAP_ID_MSI)))
718 return -EINVAL;
719
720 pci_read_config_word(dev, msi_control_reg(pos), &control);
721 if (control & PCI_MSI_FLAGS_ENABLE)
722 return 0; /* Already in MSI mode */
723
724 if (!msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
725 /* Lookup Sucess */
726 unsigned long flags;
727
728 spin_lock_irqsave(&msi_lock, flags);
729 if (!vector_irq[dev->irq]) {
730 msi_desc[dev->irq]->msi_attrib.state = 0;
731 vector_irq[dev->irq] = -1;
732 nr_released_vectors--;
733 spin_unlock_irqrestore(&msi_lock, flags);
734 enable_msi_mode(dev, pos, PCI_CAP_ID_MSI);
735 return 0;
736 }
737 spin_unlock_irqrestore(&msi_lock, flags);
738 dev->irq = temp;
739 }
740 /* Check whether driver already requested for MSI-X vectors */
741 if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) > 0 &&
742 !msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
743 printk(KERN_INFO "PCI: %s: Can't enable MSI. "
744 "Device already has MSI-X vectors assigned\n",
745 pci_name(dev));
746 dev->irq = temp;
747 return -EINVAL;
748 }
749 status = msi_capability_init(dev);
750 if (!status) {
751 if (!pos)
752 nr_reserved_vectors--; /* Only MSI capable */
753 else if (nr_msix_devices > 0)
754 nr_msix_devices--; /* Both MSI and MSI-X capable,
755 but choose enabling MSI */
756 }
757
758 return status;
759}
760
761void pci_disable_msi(struct pci_dev* dev)
762{
763 struct msi_desc *entry;
764 int pos, default_vector;
765 u16 control;
766 unsigned long flags;
767
768 if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSI)))
769 return;
770
771 pci_read_config_word(dev, msi_control_reg(pos), &control);
772 if (!(control & PCI_MSI_FLAGS_ENABLE))
773 return;
774
775 spin_lock_irqsave(&msi_lock, flags);
776 entry = msi_desc[dev->irq];
777 if (!entry || !entry->dev || entry->msi_attrib.type != PCI_CAP_ID_MSI) {
778 spin_unlock_irqrestore(&msi_lock, flags);
779 return;
780 }
781 if (entry->msi_attrib.state) {
782 spin_unlock_irqrestore(&msi_lock, flags);
783 printk(KERN_WARNING "PCI: %s: pci_disable_msi() called without "
784 "free_irq() on MSI vector %d\n",
785 pci_name(dev), dev->irq);
786 BUG_ON(entry->msi_attrib.state > 0);
787 } else {
788 vector_irq[dev->irq] = 0; /* free it */
789 nr_released_vectors++;
790 default_vector = entry->msi_attrib.default_vector;
791 spin_unlock_irqrestore(&msi_lock, flags);
792 /* Restore dev->irq to its default pin-assertion vector */
793 dev->irq = default_vector;
794 disable_msi_mode(dev, pci_find_capability(dev, PCI_CAP_ID_MSI),
795 PCI_CAP_ID_MSI);
796 }
797}
798
799static void release_msi(unsigned int vector)
800{
801 struct msi_desc *entry;
802 unsigned long flags;
803
804 spin_lock_irqsave(&msi_lock, flags);
805 entry = msi_desc[vector];
806 if (entry && entry->dev)
807 entry->msi_attrib.state = 0; /* Mark it not active */
808 spin_unlock_irqrestore(&msi_lock, flags);
809}
810
811static int msi_free_vector(struct pci_dev* dev, int vector, int reassign)
812{
813 struct msi_desc *entry;
814 int head, entry_nr, type;
815 void __iomem *base;
816 unsigned long flags;
817
818 spin_lock_irqsave(&msi_lock, flags);
819 entry = msi_desc[vector];
820 if (!entry || entry->dev != dev) {
821 spin_unlock_irqrestore(&msi_lock, flags);
822 return -EINVAL;
823 }
824 type = entry->msi_attrib.type;
825 entry_nr = entry->msi_attrib.entry_nr;
826 head = entry->link.head;
827 base = entry->mask_base;
828 msi_desc[entry->link.head]->link.tail = entry->link.tail;
829 msi_desc[entry->link.tail]->link.head = entry->link.head;
830 entry->dev = NULL;
831 if (!reassign) {
832 vector_irq[vector] = 0;
833 nr_released_vectors++;
834 }
835 msi_desc[vector] = NULL;
836 spin_unlock_irqrestore(&msi_lock, flags);
837
838 kmem_cache_free(msi_cachep, entry);
839
840 if (type == PCI_CAP_ID_MSIX) {
841 if (!reassign)
842 writel(1, base +
843 entry_nr * PCI_MSIX_ENTRY_SIZE +
844 PCI_MSIX_ENTRY_VECTOR_CTRL_OFFSET);
845
846 if (head == vector) {
847 /*
848 * Detect last MSI-X vector to be released.
849 * Release the MSI-X memory-mapped table.
850 */
851 int pos, nr_entries;
852 u32 phys_addr, table_offset;
853 u16 control;
854 u8 bir;
855
856 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
857 pci_read_config_word(dev, msi_control_reg(pos),
858 &control);
859 nr_entries = multi_msix_capable(control);
860 pci_read_config_dword(dev, msix_table_offset_reg(pos),
861 &table_offset);
862 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
863 phys_addr = pci_resource_start (dev, bir);
864 phys_addr += (u32)(table_offset &
865 ~PCI_MSIX_FLAGS_BIRMASK);
866 iounmap(base);
867 }
868 }
869
870 return 0;
871}
872
873static int reroute_msix_table(int head, struct msix_entry *entries, int *nvec)
874{
875 int vector = head, tail = 0;
876 int i, j = 0, nr_entries = 0;
877 void __iomem *base;
878 unsigned long flags;
879
880 spin_lock_irqsave(&msi_lock, flags);
881 while (head != tail) {
882 nr_entries++;
883 tail = msi_desc[vector]->link.tail;
884 if (entries[0].entry == msi_desc[vector]->msi_attrib.entry_nr)
885 j = vector;
886 vector = tail;
887 }
888 if (*nvec > nr_entries) {
889 spin_unlock_irqrestore(&msi_lock, flags);
890 *nvec = nr_entries;
891 return -EINVAL;
892 }
893 vector = ((j > 0) ? j : head);
894 for (i = 0; i < *nvec; i++) {
895 j = msi_desc[vector]->msi_attrib.entry_nr;
896 msi_desc[vector]->msi_attrib.state = 0; /* Mark it not active */
897 vector_irq[vector] = -1; /* Mark it busy */
898 nr_released_vectors--;
899 entries[i].vector = vector;
900 if (j != (entries + i)->entry) {
901 base = msi_desc[vector]->mask_base;
902 msi_desc[vector]->msi_attrib.entry_nr =
903 (entries + i)->entry;
904 writel( readl(base + j * PCI_MSIX_ENTRY_SIZE +
905 PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET), base +
906 (entries + i)->entry * PCI_MSIX_ENTRY_SIZE +
907 PCI_MSIX_ENTRY_LOWER_ADDR_OFFSET);
908 writel( readl(base + j * PCI_MSIX_ENTRY_SIZE +
909 PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET), base +
910 (entries + i)->entry * PCI_MSIX_ENTRY_SIZE +
911 PCI_MSIX_ENTRY_UPPER_ADDR_OFFSET);
912 writel( (readl(base + j * PCI_MSIX_ENTRY_SIZE +
913 PCI_MSIX_ENTRY_DATA_OFFSET) & 0xff00) | vector,
914 base + (entries+i)->entry*PCI_MSIX_ENTRY_SIZE +
915 PCI_MSIX_ENTRY_DATA_OFFSET);
916 }
917 vector = msi_desc[vector]->link.tail;
918 }
919 spin_unlock_irqrestore(&msi_lock, flags);
920
921 return 0;
922}
923
924/**
925 * pci_enable_msix - configure device's MSI-X capability structure
926 * @dev: pointer to the pci_dev data structure of MSI-X device function
927 * @data: pointer to an array of MSI-X entries
928 * @nvec: number of MSI-X vectors requested for allocation by device driver
929 *
930 * Setup the MSI-X capability structure of device function with the number
931 * of requested vectors upon its software driver call to request for
932 * MSI-X mode enabled on its hardware device function. A return of zero
933 * indicates the successful configuration of MSI-X capability structure
934 * with new allocated MSI-X vectors. A return of < 0 indicates a failure.
935 * Or a return of > 0 indicates that driver request is exceeding the number
936 * of vectors available. Driver should use the returned value to re-send
937 * its request.
938 **/
939int pci_enable_msix(struct pci_dev* dev, struct msix_entry *entries, int nvec)
940{
941 int status, pos, nr_entries, free_vectors;
942 int i, j, temp;
943 u16 control;
944 unsigned long flags;
945
946 if (!pci_msi_enable || !dev || !entries)
947 return -EINVAL;
948
949 if ((status = msi_init()) < 0)
950 return status;
951
952 if (!(pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)))
953 return -EINVAL;
954
955 pci_read_config_word(dev, msi_control_reg(pos), &control);
956 if (control & PCI_MSIX_FLAGS_ENABLE)
957 return -EINVAL; /* Already in MSI-X mode */
958
959 nr_entries = multi_msix_capable(control);
960 if (nvec > nr_entries)
961 return -EINVAL;
962
963 /* Check for any invalid entries */
964 for (i = 0; i < nvec; i++) {
965 if (entries[i].entry >= nr_entries)
966 return -EINVAL; /* invalid entry */
967 for (j = i + 1; j < nvec; j++) {
968 if (entries[i].entry == entries[j].entry)
969 return -EINVAL; /* duplicate entry */
970 }
971 }
972 temp = dev->irq;
973 if (!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
974 /* Lookup Sucess */
975 nr_entries = nvec;
976 /* Reroute MSI-X table */
977 if (reroute_msix_table(dev->irq, entries, &nr_entries)) {
978 /* #requested > #previous-assigned */
979 dev->irq = temp;
980 return nr_entries;
981 }
982 dev->irq = temp;
983 enable_msi_mode(dev, pos, PCI_CAP_ID_MSIX);
984 return 0;
985 }
986 /* Check whether driver already requested for MSI vector */
987 if (pci_find_capability(dev, PCI_CAP_ID_MSI) > 0 &&
988 !msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
989 printk(KERN_INFO "PCI: %s: Can't enable MSI-X. "
990 "Device already has an MSI vector assigned\n",
991 pci_name(dev));
992 dev->irq = temp;
993 return -EINVAL;
994 }
995
996 spin_lock_irqsave(&msi_lock, flags);
997 /*
998 * msi_lock is provided to ensure that enough vectors resources are
999 * available before granting.
1000 */
1001 free_vectors = pci_vector_resources(last_alloc_vector,
1002 nr_released_vectors);
1003 /* Ensure that each MSI/MSI-X device has one vector reserved by
1004 default to avoid any MSI-X driver to take all available
1005 resources */
1006 free_vectors -= nr_reserved_vectors;
1007 /* Find the average of free vectors among MSI-X devices */
1008 if (nr_msix_devices > 0)
1009 free_vectors /= nr_msix_devices;
1010 spin_unlock_irqrestore(&msi_lock, flags);
1011
1012 if (nvec > free_vectors) {
1013 if (free_vectors > 0)
1014 return free_vectors;
1015 else
1016 return -EBUSY;
1017 }
1018
1019 status = msix_capability_init(dev, entries, nvec);
1020 if (!status && nr_msix_devices > 0)
1021 nr_msix_devices--;
1022
1023 return status;
1024}
1025
1026void pci_disable_msix(struct pci_dev* dev)
1027{
1028 int pos, temp;
1029 u16 control;
1030
1031 if (!dev || !(pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)))
1032 return;
1033
1034 pci_read_config_word(dev, msi_control_reg(pos), &control);
1035 if (!(control & PCI_MSIX_FLAGS_ENABLE))
1036 return;
1037
1038 temp = dev->irq;
1039 if (!msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
1040 int state, vector, head, tail = 0, warning = 0;
1041 unsigned long flags;
1042
1043 vector = head = dev->irq;
1044 spin_lock_irqsave(&msi_lock, flags);
1045 while (head != tail) {
1046 state = msi_desc[vector]->msi_attrib.state;
1047 if (state)
1048 warning = 1;
1049 else {
1050 vector_irq[vector] = 0; /* free it */
1051 nr_released_vectors++;
1052 }
1053 tail = msi_desc[vector]->link.tail;
1054 vector = tail;
1055 }
1056 spin_unlock_irqrestore(&msi_lock, flags);
1057 if (warning) {
1058 dev->irq = temp;
1059 printk(KERN_WARNING "PCI: %s: pci_disable_msix() called without "
1060 "free_irq() on all MSI-X vectors\n",
1061 pci_name(dev));
1062 BUG_ON(warning > 0);
1063 } else {
1064 dev->irq = temp;
1065 disable_msi_mode(dev,
1066 pci_find_capability(dev, PCI_CAP_ID_MSIX),
1067 PCI_CAP_ID_MSIX);
1068
1069 }
1070 }
1071}
1072
1073/**
1074 * msi_remove_pci_irq_vectors - reclaim MSI(X) vectors to unused state
1075 * @dev: pointer to the pci_dev data structure of MSI(X) device function
1076 *
1077 * Being called during hotplug remove, from which the device funciton
1078 * is hot-removed. All previous assigned MSI/MSI-X vectors, if
1079 * allocated for this device function, are reclaimed to unused state,
1080 * which may be used later on.
1081 **/
1082void msi_remove_pci_irq_vectors(struct pci_dev* dev)
1083{
1084 int state, pos, temp;
1085 unsigned long flags;
1086
1087 if (!pci_msi_enable || !dev)
1088 return;
1089
1090 temp = dev->irq; /* Save IOAPIC IRQ */
1091 if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSI)) > 0 &&
1092 !msi_lookup_vector(dev, PCI_CAP_ID_MSI)) {
1093 spin_lock_irqsave(&msi_lock, flags);
1094 state = msi_desc[dev->irq]->msi_attrib.state;
1095 spin_unlock_irqrestore(&msi_lock, flags);
1096 if (state) {
1097 printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
1098 "called without free_irq() on MSI vector %d\n",
1099 pci_name(dev), dev->irq);
1100 BUG_ON(state > 0);
1101 } else /* Release MSI vector assigned to this device */
1102 msi_free_vector(dev, dev->irq, 0);
1103 dev->irq = temp; /* Restore IOAPIC IRQ */
1104 }
1105 if ((pos = pci_find_capability(dev, PCI_CAP_ID_MSIX)) > 0 &&
1106 !msi_lookup_vector(dev, PCI_CAP_ID_MSIX)) {
1107 int vector, head, tail = 0, warning = 0;
1108 void __iomem *base = NULL;
1109
1110 vector = head = dev->irq;
1111 while (head != tail) {
1112 spin_lock_irqsave(&msi_lock, flags);
1113 state = msi_desc[vector]->msi_attrib.state;
1114 tail = msi_desc[vector]->link.tail;
1115 base = msi_desc[vector]->mask_base;
1116 spin_unlock_irqrestore(&msi_lock, flags);
1117 if (state)
1118 warning = 1;
1119 else if (vector != head) /* Release MSI-X vector */
1120 msi_free_vector(dev, vector, 0);
1121 vector = tail;
1122 }
1123 msi_free_vector(dev, vector, 0);
1124 if (warning) {
1125 /* Force to release the MSI-X memory-mapped table */
1126 u32 phys_addr, table_offset;
1127 u16 control;
1128 u8 bir;
1129
1130 pci_read_config_word(dev, msi_control_reg(pos),
1131 &control);
1132 pci_read_config_dword(dev, msix_table_offset_reg(pos),
1133 &table_offset);
1134 bir = (u8)(table_offset & PCI_MSIX_FLAGS_BIRMASK);
1135 phys_addr = pci_resource_start (dev, bir);
1136 phys_addr += (u32)(table_offset &
1137 ~PCI_MSIX_FLAGS_BIRMASK);
1138 iounmap(base);
1139 printk(KERN_WARNING "PCI: %s: msi_remove_pci_irq_vectors() "
1140 "called without free_irq() on all MSI-X vectors\n",
1141 pci_name(dev));
1142 BUG_ON(warning > 0);
1143 }
1144 dev->irq = temp; /* Restore IOAPIC IRQ */
1145 }
1146}
1147
1148EXPORT_SYMBOL(pci_enable_msi);
1149EXPORT_SYMBOL(pci_disable_msi);
1150EXPORT_SYMBOL(pci_enable_msix);
1151EXPORT_SYMBOL(pci_disable_msix);
generated by cgit v1.2.2 (git 2.25.0) at 2024-11-19 03:08:34 -0500