1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2015 Broadcom Corporation
4 */
5
6#include <linux/interrupt.h>
7#include <linux/irqchip/chained_irq.h>
8#include <linux/irqdomain.h>
9#include <linux/msi.h>
10#include <linux/of_irq.h>
11#include <linux/of_pci.h>
12#include <linux/pci.h>
13
14#include "pcie-iproc.h"
15
16#define IPROC_MSI_INTR_EN_SHIFT 11
17#define IPROC_MSI_INTR_EN BIT(IPROC_MSI_INTR_EN_SHIFT)
18#define IPROC_MSI_INT_N_EVENT_SHIFT 1
19#define IPROC_MSI_INT_N_EVENT BIT(IPROC_MSI_INT_N_EVENT_SHIFT)
20#define IPROC_MSI_EQ_EN_SHIFT 0
21#define IPROC_MSI_EQ_EN BIT(IPROC_MSI_EQ_EN_SHIFT)
22
23#define IPROC_MSI_EQ_MASK 0x3f
24
25/* Max number of GIC interrupts */
26#define NR_HW_IRQS 6
27
28/* Number of entries in each event queue */
29#define EQ_LEN 64
30
31/* Size of each event queue memory region */
32#define EQ_MEM_REGION_SIZE SZ_4K
33
34/* Size of each MSI address region */
35#define MSI_MEM_REGION_SIZE SZ_4K
36
37enum iproc_msi_reg {
38 IPROC_MSI_EQ_PAGE = 0,
39 IPROC_MSI_EQ_PAGE_UPPER,
40 IPROC_MSI_PAGE,
41 IPROC_MSI_PAGE_UPPER,
42 IPROC_MSI_CTRL,
43 IPROC_MSI_EQ_HEAD,
44 IPROC_MSI_EQ_TAIL,
45 IPROC_MSI_INTS_EN,
46 IPROC_MSI_REG_SIZE,
47};
48
49struct iproc_msi;
50
51/**
52 * struct iproc_msi_grp - iProc MSI group
53 *
54 * One MSI group is allocated per GIC interrupt, serviced by one iProc MSI
55 * event queue.
56 *
57 * @msi: pointer to iProc MSI data
58 * @gic_irq: GIC interrupt
59 * @eq: Event queue number
60 */
61struct iproc_msi_grp {
62 struct iproc_msi *msi;
63 int gic_irq;
64 unsigned int eq;
65};
66
67/**
68 * struct iproc_msi - iProc event queue based MSI
69 *
70 * Only meant to be used on platforms without MSI support integrated into the
71 * GIC.
72 *
73 * @pcie: pointer to iProc PCIe data
74 * @reg_offsets: MSI register offsets
75 * @grps: MSI groups
76 * @nr_irqs: number of total interrupts connected to GIC
77 * @nr_cpus: number of toal CPUs
78 * @has_inten_reg: indicates the MSI interrupt enable register needs to be
79 * set explicitly (required for some legacy platforms)
80 * @bitmap: MSI vector bitmap
81 * @bitmap_lock: lock to protect access to the MSI bitmap
82 * @nr_msi_vecs: total number of MSI vectors
83 * @inner_domain: inner IRQ domain
84 * @msi_domain: MSI IRQ domain
85 * @nr_eq_region: required number of 4K aligned memory region for MSI event
86 * queues
87 * @nr_msi_region: required number of 4K aligned address region for MSI posted
88 * writes
89 * @eq_cpu: pointer to allocated memory region for MSI event queues
90 * @eq_dma: DMA address of MSI event queues
91 * @msi_addr: MSI address
92 */
93struct iproc_msi {
94 struct iproc_pcie *pcie;
95 const u16 (*reg_offsets)[IPROC_MSI_REG_SIZE];
96 struct iproc_msi_grp *grps;
97 int nr_irqs;
98 int nr_cpus;
99 bool has_inten_reg;
100 unsigned long *bitmap;
101 struct mutex bitmap_lock;
102 unsigned int nr_msi_vecs;
103 struct irq_domain *inner_domain;
104 struct irq_domain *msi_domain;
105 unsigned int nr_eq_region;
106 unsigned int nr_msi_region;
107 void *eq_cpu;
108 dma_addr_t eq_dma;
109 phys_addr_t msi_addr;
110};
111
112static const u16 iproc_msi_reg_paxb[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = {
113 { 0x200, 0x2c0, 0x204, 0x2c4, 0x210, 0x250, 0x254, 0x208 },
114 { 0x200, 0x2c0, 0x204, 0x2c4, 0x214, 0x258, 0x25c, 0x208 },
115 { 0x200, 0x2c0, 0x204, 0x2c4, 0x218, 0x260, 0x264, 0x208 },
116 { 0x200, 0x2c0, 0x204, 0x2c4, 0x21c, 0x268, 0x26c, 0x208 },
117 { 0x200, 0x2c0, 0x204, 0x2c4, 0x220, 0x270, 0x274, 0x208 },
118 { 0x200, 0x2c0, 0x204, 0x2c4, 0x224, 0x278, 0x27c, 0x208 },
119};
120
121static const u16 iproc_msi_reg_paxc[NR_HW_IRQS][IPROC_MSI_REG_SIZE] = {
122 { 0xc00, 0xc04, 0xc08, 0xc0c, 0xc40, 0xc50, 0xc60 },
123 { 0xc10, 0xc14, 0xc18, 0xc1c, 0xc44, 0xc54, 0xc64 },
124 { 0xc20, 0xc24, 0xc28, 0xc2c, 0xc48, 0xc58, 0xc68 },
125 { 0xc30, 0xc34, 0xc38, 0xc3c, 0xc4c, 0xc5c, 0xc6c },
126};
127
128static inline u32 iproc_msi_read_reg(struct iproc_msi *msi,
129 enum iproc_msi_reg reg,
130 unsigned int eq)
131{
132 struct iproc_pcie *pcie = msi->pcie;
133
134 return readl_relaxed(pcie->base + msi->reg_offsets[eq][reg]);
135}
136
137static inline void iproc_msi_write_reg(struct iproc_msi *msi,
138 enum iproc_msi_reg reg,
139 int eq, u32 val)
140{
141 struct iproc_pcie *pcie = msi->pcie;
142
143 writel_relaxed(val, pcie->base + msi->reg_offsets[eq][reg]);
144}
145
146static inline u32 hwirq_to_group(struct iproc_msi *msi, unsigned long hwirq)
147{
148 return (hwirq % msi->nr_irqs);
149}
150
151static inline unsigned int iproc_msi_addr_offset(struct iproc_msi *msi,
152 unsigned long hwirq)
153{
154 if (msi->nr_msi_region > 1)
155 return hwirq_to_group(msi, hwirq) * MSI_MEM_REGION_SIZE;
156 else
157 return hwirq_to_group(msi, hwirq) * sizeof(u32);
158}
159
160static inline unsigned int iproc_msi_eq_offset(struct iproc_msi *msi, u32 eq)
161{
162 if (msi->nr_eq_region > 1)
163 return eq * EQ_MEM_REGION_SIZE;
164 else
165 return eq * EQ_LEN * sizeof(u32);
166}
167
168static struct irq_chip iproc_msi_irq_chip = {
169 .name = "iProc-MSI",
170};
171
172static struct msi_domain_info iproc_msi_domain_info = {
173 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
174 MSI_FLAG_PCI_MSIX,
175 .chip = &iproc_msi_irq_chip,
176};
177
178/*
179 * In iProc PCIe core, each MSI group is serviced by a GIC interrupt and a
180 * dedicated event queue. Each MSI group can support up to 64 MSI vectors.
181 *
182 * The number of MSI groups varies between different iProc SoCs. The total
183 * number of CPU cores also varies. To support MSI IRQ affinity, we
184 * distribute GIC interrupts across all available CPUs. MSI vector is moved
185 * from one GIC interrupt to another to steer to the target CPU.
186 *
187 * Assuming:
188 * - the number of MSI groups is M
189 * - the number of CPU cores is N
190 * - M is always a multiple of N
191 *
192 * Total number of raw MSI vectors = M * 64
193 * Total number of supported MSI vectors = (M * 64) / N
194 */
195static inline int hwirq_to_cpu(struct iproc_msi *msi, unsigned long hwirq)
196{
197 return (hwirq % msi->nr_cpus);
198}
199
200static inline unsigned long hwirq_to_canonical_hwirq(struct iproc_msi *msi,
201 unsigned long hwirq)
202{
203 return (hwirq - hwirq_to_cpu(msi, hwirq));
204}
205
206static int iproc_msi_irq_set_affinity(struct irq_data *data,
207 const struct cpumask *mask, bool force)
208{
209 struct iproc_msi *msi = irq_data_get_irq_chip_data(d: data);
210 int target_cpu = cpumask_first(srcp: mask);
211 int curr_cpu;
212 int ret;
213
214 curr_cpu = hwirq_to_cpu(msi, hwirq: data->hwirq);
215 if (curr_cpu == target_cpu)
216 ret = IRQ_SET_MASK_OK_DONE;
217 else {
218 /* steer MSI to the target CPU */
219 data->hwirq = hwirq_to_canonical_hwirq(msi, hwirq: data->hwirq) + target_cpu;
220 ret = IRQ_SET_MASK_OK;
221 }
222
223 irq_data_update_effective_affinity(d: data, cpumask_of(target_cpu));
224
225 return ret;
226}
227
228static void iproc_msi_irq_compose_msi_msg(struct irq_data *data,
229 struct msi_msg *msg)
230{
231 struct iproc_msi *msi = irq_data_get_irq_chip_data(d: data);
232 dma_addr_t addr;
233
234 addr = msi->msi_addr + iproc_msi_addr_offset(msi, hwirq: data->hwirq);
235 msg->address_lo = lower_32_bits(addr);
236 msg->address_hi = upper_32_bits(addr);
237 msg->data = data->hwirq << 5;
238}
239
240static struct irq_chip iproc_msi_bottom_irq_chip = {
241 .name = "MSI",
242 .irq_set_affinity = iproc_msi_irq_set_affinity,
243 .irq_compose_msi_msg = iproc_msi_irq_compose_msi_msg,
244};
245
246static int iproc_msi_irq_domain_alloc(struct irq_domain *domain,
247 unsigned int virq, unsigned int nr_irqs,
248 void *args)
249{
250 struct iproc_msi *msi = domain->host_data;
251 int hwirq, i;
252
253 if (msi->nr_cpus > 1 && nr_irqs > 1)
254 return -EINVAL;
255
256 mutex_lock(&msi->bitmap_lock);
257
258 /*
259 * Allocate 'nr_irqs' multiplied by 'nr_cpus' number of MSI vectors
260 * each time
261 */
262 hwirq = bitmap_find_free_region(bitmap: msi->bitmap, bits: msi->nr_msi_vecs,
263 order_base_2(msi->nr_cpus * nr_irqs));
264
265 mutex_unlock(lock: &msi->bitmap_lock);
266
267 if (hwirq < 0)
268 return -ENOSPC;
269
270 for (i = 0; i < nr_irqs; i++) {
271 irq_domain_set_info(domain, virq: virq + i, hwirq: hwirq + i,
272 chip: &iproc_msi_bottom_irq_chip,
273 chip_data: domain->host_data, handler: handle_simple_irq,
274 NULL, NULL);
275 }
276
277 return 0;
278}
279
280static void iproc_msi_irq_domain_free(struct irq_domain *domain,
281 unsigned int virq, unsigned int nr_irqs)
282{
283 struct irq_data *data = irq_domain_get_irq_data(domain, virq);
284 struct iproc_msi *msi = irq_data_get_irq_chip_data(d: data);
285 unsigned int hwirq;
286
287 mutex_lock(&msi->bitmap_lock);
288
289 hwirq = hwirq_to_canonical_hwirq(msi, hwirq: data->hwirq);
290 bitmap_release_region(bitmap: msi->bitmap, pos: hwirq,
291 order_base_2(msi->nr_cpus * nr_irqs));
292
293 mutex_unlock(lock: &msi->bitmap_lock);
294
295 irq_domain_free_irqs_parent(domain, irq_base: virq, nr_irqs);
296}
297
298static const struct irq_domain_ops msi_domain_ops = {
299 .alloc = iproc_msi_irq_domain_alloc,
300 .free = iproc_msi_irq_domain_free,
301};
302
303static inline u32 decode_msi_hwirq(struct iproc_msi *msi, u32 eq, u32 head)
304{
305 u32 __iomem *msg;
306 u32 hwirq;
307 unsigned int offs;
308
309 offs = iproc_msi_eq_offset(msi, eq) + head * sizeof(u32);
310 msg = (u32 __iomem *)(msi->eq_cpu + offs);
311 hwirq = readl(addr: msg);
312 hwirq = (hwirq >> 5) + (hwirq & 0x1f);
313
314 /*
315 * Since we have multiple hwirq mapped to a single MSI vector,
316 * now we need to derive the hwirq at CPU0. It can then be used to
317 * mapped back to virq.
318 */
319 return hwirq_to_canonical_hwirq(msi, hwirq);
320}
321
322static void iproc_msi_handler(struct irq_desc *desc)
323{
324 struct irq_chip *chip = irq_desc_get_chip(desc);
325 struct iproc_msi_grp *grp;
326 struct iproc_msi *msi;
327 u32 eq, head, tail, nr_events;
328 unsigned long hwirq;
329
330 chained_irq_enter(chip, desc);
331
332 grp = irq_desc_get_handler_data(desc);
333 msi = grp->msi;
334 eq = grp->eq;
335
336 /*
337 * iProc MSI event queue is tracked by head and tail pointers. Head
338 * pointer indicates the next entry (MSI data) to be consumed by SW in
339 * the queue and needs to be updated by SW. iProc MSI core uses the
340 * tail pointer as the next data insertion point.
341 *
342 * Entries between head and tail pointers contain valid MSI data. MSI
343 * data is guaranteed to be in the event queue memory before the tail
344 * pointer is updated by the iProc MSI core.
345 */
346 head = iproc_msi_read_reg(msi, reg: IPROC_MSI_EQ_HEAD,
347 eq) & IPROC_MSI_EQ_MASK;
348 do {
349 tail = iproc_msi_read_reg(msi, reg: IPROC_MSI_EQ_TAIL,
350 eq) & IPROC_MSI_EQ_MASK;
351
352 /*
353 * Figure out total number of events (MSI data) to be
354 * processed.
355 */
356 nr_events = (tail < head) ?
357 (EQ_LEN - (head - tail)) : (tail - head);
358 if (!nr_events)
359 break;
360
361 /* process all outstanding events */
362 while (nr_events--) {
363 hwirq = decode_msi_hwirq(msi, eq, head);
364 generic_handle_domain_irq(domain: msi->inner_domain, hwirq);
365
366 head++;
367 head %= EQ_LEN;
368 }
369
370 /*
371 * Now all outstanding events have been processed. Update the
372 * head pointer.
373 */
374 iproc_msi_write_reg(msi, reg: IPROC_MSI_EQ_HEAD, eq, val: head);
375
376 /*
377 * Now go read the tail pointer again to see if there are new
378 * outstanding events that came in during the above window.
379 */
380 } while (true);
381
382 chained_irq_exit(chip, desc);
383}
384
385static void iproc_msi_enable(struct iproc_msi *msi)
386{
387 int i, eq;
388 u32 val;
389
390 /* Program memory region for each event queue */
391 for (i = 0; i < msi->nr_eq_region; i++) {
392 dma_addr_t addr = msi->eq_dma + (i * EQ_MEM_REGION_SIZE);
393
394 iproc_msi_write_reg(msi, reg: IPROC_MSI_EQ_PAGE, eq: i,
395 lower_32_bits(addr));
396 iproc_msi_write_reg(msi, reg: IPROC_MSI_EQ_PAGE_UPPER, eq: i,
397 upper_32_bits(addr));
398 }
399
400 /* Program address region for MSI posted writes */
401 for (i = 0; i < msi->nr_msi_region; i++) {
402 phys_addr_t addr = msi->msi_addr + (i * MSI_MEM_REGION_SIZE);
403
404 iproc_msi_write_reg(msi, reg: IPROC_MSI_PAGE, eq: i,
405 lower_32_bits(addr));
406 iproc_msi_write_reg(msi, reg: IPROC_MSI_PAGE_UPPER, eq: i,
407 upper_32_bits(addr));
408 }
409
410 for (eq = 0; eq < msi->nr_irqs; eq++) {
411 /* Enable MSI event queue */
412 val = IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT |
413 IPROC_MSI_EQ_EN;
414 iproc_msi_write_reg(msi, reg: IPROC_MSI_CTRL, eq, val);
415
416 /*
417 * Some legacy platforms require the MSI interrupt enable
418 * register to be set explicitly.
419 */
420 if (msi->has_inten_reg) {
421 val = iproc_msi_read_reg(msi, reg: IPROC_MSI_INTS_EN, eq);
422 val |= BIT(eq);
423 iproc_msi_write_reg(msi, reg: IPROC_MSI_INTS_EN, eq, val);
424 }
425 }
426}
427
428static void iproc_msi_disable(struct iproc_msi *msi)
429{
430 u32 eq, val;
431
432 for (eq = 0; eq < msi->nr_irqs; eq++) {
433 if (msi->has_inten_reg) {
434 val = iproc_msi_read_reg(msi, reg: IPROC_MSI_INTS_EN, eq);
435 val &= ~BIT(eq);
436 iproc_msi_write_reg(msi, reg: IPROC_MSI_INTS_EN, eq, val);
437 }
438
439 val = iproc_msi_read_reg(msi, reg: IPROC_MSI_CTRL, eq);
440 val &= ~(IPROC_MSI_INTR_EN | IPROC_MSI_INT_N_EVENT |
441 IPROC_MSI_EQ_EN);
442 iproc_msi_write_reg(msi, reg: IPROC_MSI_CTRL, eq, val);
443 }
444}
445
446static int iproc_msi_alloc_domains(struct device_node *node,
447 struct iproc_msi *msi)
448{
449 msi->inner_domain = irq_domain_add_linear(NULL, size: msi->nr_msi_vecs,
450 ops: &msi_domain_ops, host_data: msi);
451 if (!msi->inner_domain)
452 return -ENOMEM;
453
454 msi->msi_domain = pci_msi_create_irq_domain(fwnode: of_node_to_fwnode(node),
455 info: &iproc_msi_domain_info,
456 parent: msi->inner_domain);
457 if (!msi->msi_domain) {
458 irq_domain_remove(host: msi->inner_domain);
459 return -ENOMEM;
460 }
461
462 return 0;
463}
464
465static void iproc_msi_free_domains(struct iproc_msi *msi)
466{
467 if (msi->msi_domain)
468 irq_domain_remove(host: msi->msi_domain);
469
470 if (msi->inner_domain)
471 irq_domain_remove(host: msi->inner_domain);
472}
473
474static void iproc_msi_irq_free(struct iproc_msi *msi, unsigned int cpu)
475{
476 int i;
477
478 for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) {
479 irq_set_chained_handler_and_data(irq: msi->grps[i].gic_irq,
480 NULL, NULL);
481 }
482}
483
484static int iproc_msi_irq_setup(struct iproc_msi *msi, unsigned int cpu)
485{
486 int i, ret;
487 cpumask_var_t mask;
488 struct iproc_pcie *pcie = msi->pcie;
489
490 for (i = cpu; i < msi->nr_irqs; i += msi->nr_cpus) {
491 irq_set_chained_handler_and_data(irq: msi->grps[i].gic_irq,
492 handle: iproc_msi_handler,
493 data: &msi->grps[i]);
494 /* Dedicate GIC interrupt to each CPU core */
495 if (alloc_cpumask_var(mask: &mask, GFP_KERNEL)) {
496 cpumask_clear(dstp: mask);
497 cpumask_set_cpu(cpu, dstp: mask);
498 ret = irq_set_affinity(irq: msi->grps[i].gic_irq, cpumask: mask);
499 if (ret)
500 dev_err(pcie->dev,
501 "failed to set affinity for IRQ%d\n",
502 msi->grps[i].gic_irq);
503 free_cpumask_var(mask);
504 } else {
505 dev_err(pcie->dev, "failed to alloc CPU mask\n");
506 ret = -EINVAL;
507 }
508
509 if (ret) {
510 /* Free all configured/unconfigured IRQs */
511 iproc_msi_irq_free(msi, cpu);
512 return ret;
513 }
514 }
515
516 return 0;
517}
518
519int iproc_msi_init(struct iproc_pcie *pcie, struct device_node *node)
520{
521 struct iproc_msi *msi;
522 int i, ret;
523 unsigned int cpu;
524
525 if (!of_device_is_compatible(device: node, "brcm,iproc-msi"))
526 return -ENODEV;
527
528 if (!of_property_read_bool(np: node, propname: "msi-controller"))
529 return -ENODEV;
530
531 if (pcie->msi)
532 return -EBUSY;
533
534 msi = devm_kzalloc(dev: pcie->dev, size: sizeof(*msi), GFP_KERNEL);
535 if (!msi)
536 return -ENOMEM;
537
538 msi->pcie = pcie;
539 pcie->msi = msi;
540 msi->msi_addr = pcie->base_addr;
541 mutex_init(&msi->bitmap_lock);
542 msi->nr_cpus = num_possible_cpus();
543
544 if (msi->nr_cpus == 1)
545 iproc_msi_domain_info.flags |= MSI_FLAG_MULTI_PCI_MSI;
546
547 msi->nr_irqs = of_irq_count(dev: node);
548 if (!msi->nr_irqs) {
549 dev_err(pcie->dev, "found no MSI GIC interrupt\n");
550 return -ENODEV;
551 }
552
553 if (msi->nr_irqs > NR_HW_IRQS) {
554 dev_warn(pcie->dev, "too many MSI GIC interrupts defined %d\n",
555 msi->nr_irqs);
556 msi->nr_irqs = NR_HW_IRQS;
557 }
558
559 if (msi->nr_irqs < msi->nr_cpus) {
560 dev_err(pcie->dev,
561 "not enough GIC interrupts for MSI affinity\n");
562 return -EINVAL;
563 }
564
565 if (msi->nr_irqs % msi->nr_cpus != 0) {
566 msi->nr_irqs -= msi->nr_irqs % msi->nr_cpus;
567 dev_warn(pcie->dev, "Reducing number of interrupts to %d\n",
568 msi->nr_irqs);
569 }
570
571 switch (pcie->type) {
572 case IPROC_PCIE_PAXB_BCMA:
573 case IPROC_PCIE_PAXB:
574 msi->reg_offsets = iproc_msi_reg_paxb;
575 msi->nr_eq_region = 1;
576 msi->nr_msi_region = 1;
577 break;
578 case IPROC_PCIE_PAXC:
579 msi->reg_offsets = iproc_msi_reg_paxc;
580 msi->nr_eq_region = msi->nr_irqs;
581 msi->nr_msi_region = msi->nr_irqs;
582 break;
583 default:
584 dev_err(pcie->dev, "incompatible iProc PCIe interface\n");
585 return -EINVAL;
586 }
587
588 msi->has_inten_reg = of_property_read_bool(np: node, propname: "brcm,pcie-msi-inten");
589
590 msi->nr_msi_vecs = msi->nr_irqs * EQ_LEN;
591 msi->bitmap = devm_bitmap_zalloc(dev: pcie->dev, nbits: msi->nr_msi_vecs,
592 GFP_KERNEL);
593 if (!msi->bitmap)
594 return -ENOMEM;
595
596 msi->grps = devm_kcalloc(dev: pcie->dev, n: msi->nr_irqs, size: sizeof(*msi->grps),
597 GFP_KERNEL);
598 if (!msi->grps)
599 return -ENOMEM;
600
601 for (i = 0; i < msi->nr_irqs; i++) {
602 unsigned int irq = irq_of_parse_and_map(node, index: i);
603
604 if (!irq) {
605 dev_err(pcie->dev, "unable to parse/map interrupt\n");
606 ret = -ENODEV;
607 goto free_irqs;
608 }
609 msi->grps[i].gic_irq = irq;
610 msi->grps[i].msi = msi;
611 msi->grps[i].eq = i;
612 }
613
614 /* Reserve memory for event queue and make sure memories are zeroed */
615 msi->eq_cpu = dma_alloc_coherent(dev: pcie->dev,
616 size: msi->nr_eq_region * EQ_MEM_REGION_SIZE,
617 dma_handle: &msi->eq_dma, GFP_KERNEL);
618 if (!msi->eq_cpu) {
619 ret = -ENOMEM;
620 goto free_irqs;
621 }
622
623 ret = iproc_msi_alloc_domains(node, msi);
624 if (ret) {
625 dev_err(pcie->dev, "failed to create MSI domains\n");
626 goto free_eq_dma;
627 }
628
629 for_each_online_cpu(cpu) {
630 ret = iproc_msi_irq_setup(msi, cpu);
631 if (ret)
632 goto free_msi_irq;
633 }
634
635 iproc_msi_enable(msi);
636
637 return 0;
638
639free_msi_irq:
640 for_each_online_cpu(cpu)
641 iproc_msi_irq_free(msi, cpu);
642 iproc_msi_free_domains(msi);
643
644free_eq_dma:
645 dma_free_coherent(dev: pcie->dev, size: msi->nr_eq_region * EQ_MEM_REGION_SIZE,
646 cpu_addr: msi->eq_cpu, dma_handle: msi->eq_dma);
647
648free_irqs:
649 for (i = 0; i < msi->nr_irqs; i++) {
650 if (msi->grps[i].gic_irq)
651 irq_dispose_mapping(virq: msi->grps[i].gic_irq);
652 }
653 pcie->msi = NULL;
654 return ret;
655}
656EXPORT_SYMBOL(iproc_msi_init);
657
658void iproc_msi_exit(struct iproc_pcie *pcie)
659{
660 struct iproc_msi *msi = pcie->msi;
661 unsigned int i, cpu;
662
663 if (!msi)
664 return;
665
666 iproc_msi_disable(msi);
667
668 for_each_online_cpu(cpu)
669 iproc_msi_irq_free(msi, cpu);
670
671 iproc_msi_free_domains(msi);
672
673 dma_free_coherent(dev: pcie->dev, size: msi->nr_eq_region * EQ_MEM_REGION_SIZE,
674 cpu_addr: msi->eq_cpu, dma_handle: msi->eq_dma);
675
676 for (i = 0; i < msi->nr_irqs; i++) {
677 if (msi->grps[i].gic_irq)
678 irq_dispose_mapping(virq: msi->grps[i].gic_irq);
679 }
680}
681EXPORT_SYMBOL(iproc_msi_exit);
682

source code of linux/drivers/pci/controller/pcie-iproc-msi.c