1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Support of MSI, HPET and DMAR interrupts.
4 *
5 * Copyright (C) 1997, 1998, 1999, 2000, 2009 Ingo Molnar, Hajnalka Szabo
6 * Moved from arch/x86/kernel/apic/io_apic.c.
7 * Jiang Liu <jiang.liu@linux.intel.com>
8 * Convert to hierarchical irqdomain
9 */
10 #include <linux/mm.h>
11 #include <linux/interrupt.h>
12 #include <linux/irq.h>
13 #include <linux/pci.h>
14 #include <linux/dmar.h>
15 #include <linux/hpet.h>
16 #include <linux/msi.h>
17 #include <asm/irqdomain.h>
18 #include <asm/msidef.h>
19 #include <asm/hpet.h>
20 #include <asm/hw_irq.h>
21 #include <asm/apic.h>
22 #include <asm/irq_remapping.h>
23
24 static struct irq_domain *msi_default_domain;
25
__irq_msi_compose_msg(struct irq_cfg * cfg,struct msi_msg * msg)26 static void __irq_msi_compose_msg(struct irq_cfg *cfg, struct msi_msg *msg)
27 {
28 msg->address_hi = MSI_ADDR_BASE_HI;
29
30 if (x2apic_enabled())
31 msg->address_hi |= MSI_ADDR_EXT_DEST_ID(cfg->dest_apicid);
32
33 msg->address_lo =
34 MSI_ADDR_BASE_LO |
35 ((apic->irq_dest_mode == 0) ?
36 MSI_ADDR_DEST_MODE_PHYSICAL :
37 MSI_ADDR_DEST_MODE_LOGICAL) |
38 MSI_ADDR_REDIRECTION_CPU |
39 MSI_ADDR_DEST_ID(cfg->dest_apicid);
40
41 msg->data =
42 MSI_DATA_TRIGGER_EDGE |
43 MSI_DATA_LEVEL_ASSERT |
44 MSI_DATA_DELIVERY_FIXED |
45 MSI_DATA_VECTOR(cfg->vector);
46 }
47
irq_msi_compose_msg(struct irq_data * data,struct msi_msg * msg)48 static void irq_msi_compose_msg(struct irq_data *data, struct msi_msg *msg)
49 {
50 __irq_msi_compose_msg(irqd_cfg(data), msg);
51 }
52
irq_msi_update_msg(struct irq_data * irqd,struct irq_cfg * cfg)53 static void irq_msi_update_msg(struct irq_data *irqd, struct irq_cfg *cfg)
54 {
55 struct msi_msg msg[2] = { [1] = { }, };
56
57 __irq_msi_compose_msg(cfg, msg);
58 irq_data_get_irq_chip(irqd)->irq_write_msi_msg(irqd, msg);
59 }
60
61 static int
msi_set_affinity(struct irq_data * irqd,const struct cpumask * mask,bool force)62 msi_set_affinity(struct irq_data *irqd, const struct cpumask *mask, bool force)
63 {
64 struct irq_cfg old_cfg, *cfg = irqd_cfg(irqd);
65 struct irq_data *parent = irqd->parent_data;
66 unsigned int cpu;
67 int ret;
68
69 /* Save the current configuration */
70 cpu = cpumask_first(irq_data_get_effective_affinity_mask(irqd));
71 old_cfg = *cfg;
72
73 /* Allocate a new target vector */
74 ret = parent->chip->irq_set_affinity(parent, mask, force);
75 if (ret < 0 || ret == IRQ_SET_MASK_OK_DONE)
76 return ret;
77
78 /*
79 * For non-maskable and non-remapped MSI interrupts the migration
80 * to a different destination CPU and a different vector has to be
81 * done careful to handle the possible stray interrupt which can be
82 * caused by the non-atomic update of the address/data pair.
83 *
84 * Direct update is possible when:
85 * - The MSI is maskable (remapped MSI does not use this code path)).
86 * The quirk bit is not set in this case.
87 * - The new vector is the same as the old vector
88 * - The old vector is MANAGED_IRQ_SHUTDOWN_VECTOR (interrupt starts up)
89 * - The interrupt is not yet started up
90 * - The new destination CPU is the same as the old destination CPU
91 */
92 if (!irqd_msi_nomask_quirk(irqd) ||
93 cfg->vector == old_cfg.vector ||
94 old_cfg.vector == MANAGED_IRQ_SHUTDOWN_VECTOR ||
95 !irqd_is_started(irqd) ||
96 cfg->dest_apicid == old_cfg.dest_apicid) {
97 irq_msi_update_msg(irqd, cfg);
98 return ret;
99 }
100
101 /*
102 * Paranoia: Validate that the interrupt target is the local
103 * CPU.
104 */
105 if (WARN_ON_ONCE(cpu != smp_processor_id())) {
106 irq_msi_update_msg(irqd, cfg);
107 return ret;
108 }
109
110 /*
111 * Redirect the interrupt to the new vector on the current CPU
112 * first. This might cause a spurious interrupt on this vector if
113 * the device raises an interrupt right between this update and the
114 * update to the final destination CPU.
115 *
116 * If the vector is in use then the installed device handler will
117 * denote it as spurious which is no harm as this is a rare event
118 * and interrupt handlers have to cope with spurious interrupts
119 * anyway. If the vector is unused, then it is marked so it won't
120 * trigger the 'No irq handler for vector' warning in do_IRQ().
121 *
122 * This requires to hold vector lock to prevent concurrent updates to
123 * the affected vector.
124 */
125 lock_vector_lock();
126
127 /*
128 * Mark the new target vector on the local CPU if it is currently
129 * unused. Reuse the VECTOR_RETRIGGERED state which is also used in
130 * the CPU hotplug path for a similar purpose. This cannot be
131 * undone here as the current CPU has interrupts disabled and
132 * cannot handle the interrupt before the whole set_affinity()
133 * section is done. In the CPU unplug case, the current CPU is
134 * about to vanish and will not handle any interrupts anymore. The
135 * vector is cleaned up when the CPU comes online again.
136 */
137 if (IS_ERR_OR_NULL(this_cpu_read(vector_irq[cfg->vector])))
138 this_cpu_write(vector_irq[cfg->vector], VECTOR_RETRIGGERED);
139
140 /* Redirect it to the new vector on the local CPU temporarily */
141 old_cfg.vector = cfg->vector;
142 irq_msi_update_msg(irqd, &old_cfg);
143
144 /* Now transition it to the target CPU */
145 irq_msi_update_msg(irqd, cfg);
146
147 /*
148 * All interrupts after this point are now targeted at the new
149 * vector/CPU.
150 *
151 * Drop vector lock before testing whether the temporary assignment
152 * to the local CPU was hit by an interrupt raised in the device,
153 * because the retrigger function acquires vector lock again.
154 */
155 unlock_vector_lock();
156
157 /*
158 * Check whether the transition raced with a device interrupt and
159 * is pending in the local APICs IRR. It is safe to do this outside
160 * of vector lock as the irq_desc::lock of this interrupt is still
161 * held and interrupts are disabled: The check is not accessing the
162 * underlying vector store. It's just checking the local APIC's
163 * IRR.
164 */
165 if (lapic_vector_set_in_irr(cfg->vector))
166 irq_data_get_irq_chip(irqd)->irq_retrigger(irqd);
167
168 return ret;
169 }
170
171 /*
172 * IRQ Chip for MSI PCI/PCI-X/PCI-Express Devices,
173 * which implement the MSI or MSI-X Capability Structure.
174 */
175 static struct irq_chip pci_msi_controller = {
176 .name = "PCI-MSI",
177 .irq_unmask = pci_msi_unmask_irq,
178 .irq_mask = pci_msi_mask_irq,
179 .irq_ack = irq_chip_ack_parent,
180 .irq_retrigger = irq_chip_retrigger_hierarchy,
181 .irq_compose_msi_msg = irq_msi_compose_msg,
182 .irq_set_affinity = msi_set_affinity,
183 .flags = IRQCHIP_SKIP_SET_WAKE |
184 IRQCHIP_AFFINITY_PRE_STARTUP,
185 };
186
native_setup_msi_irqs(struct pci_dev * dev,int nvec,int type)187 int native_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
188 {
189 struct irq_domain *domain;
190 struct irq_alloc_info info;
191
192 init_irq_alloc_info(&info, NULL);
193 info.type = X86_IRQ_ALLOC_TYPE_MSI;
194 info.msi_dev = dev;
195
196 domain = irq_remapping_get_irq_domain(&info);
197 if (domain == NULL)
198 domain = msi_default_domain;
199 if (domain == NULL)
200 return -ENOSYS;
201
202 return msi_domain_alloc_irqs(domain, &dev->dev, nvec);
203 }
204
native_teardown_msi_irq(unsigned int irq)205 void native_teardown_msi_irq(unsigned int irq)
206 {
207 irq_domain_free_irqs(irq, 1);
208 }
209
pci_msi_get_hwirq(struct msi_domain_info * info,msi_alloc_info_t * arg)210 static irq_hw_number_t pci_msi_get_hwirq(struct msi_domain_info *info,
211 msi_alloc_info_t *arg)
212 {
213 return arg->msi_hwirq;
214 }
215
pci_msi_prepare(struct irq_domain * domain,struct device * dev,int nvec,msi_alloc_info_t * arg)216 int pci_msi_prepare(struct irq_domain *domain, struct device *dev, int nvec,
217 msi_alloc_info_t *arg)
218 {
219 struct pci_dev *pdev = to_pci_dev(dev);
220 struct msi_desc *desc = first_pci_msi_entry(pdev);
221
222 init_irq_alloc_info(arg, NULL);
223 arg->msi_dev = pdev;
224 if (desc->msi_attrib.is_msix) {
225 arg->type = X86_IRQ_ALLOC_TYPE_MSIX;
226 } else {
227 arg->type = X86_IRQ_ALLOC_TYPE_MSI;
228 arg->flags |= X86_IRQ_ALLOC_CONTIGUOUS_VECTORS;
229 }
230
231 return 0;
232 }
233 EXPORT_SYMBOL_GPL(pci_msi_prepare);
234
pci_msi_set_desc(msi_alloc_info_t * arg,struct msi_desc * desc)235 void pci_msi_set_desc(msi_alloc_info_t *arg, struct msi_desc *desc)
236 {
237 arg->msi_hwirq = pci_msi_domain_calc_hwirq(arg->msi_dev, desc);
238 }
239 EXPORT_SYMBOL_GPL(pci_msi_set_desc);
240
241 static struct msi_domain_ops pci_msi_domain_ops = {
242 .get_hwirq = pci_msi_get_hwirq,
243 .msi_prepare = pci_msi_prepare,
244 .set_desc = pci_msi_set_desc,
245 };
246
247 static struct msi_domain_info pci_msi_domain_info = {
248 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
249 MSI_FLAG_PCI_MSIX,
250 .ops = &pci_msi_domain_ops,
251 .chip = &pci_msi_controller,
252 .handler = handle_edge_irq,
253 .handler_name = "edge",
254 };
255
arch_init_msi_domain(struct irq_domain * parent)256 void __init arch_init_msi_domain(struct irq_domain *parent)
257 {
258 struct fwnode_handle *fn;
259
260 if (disable_apic)
261 return;
262
263 fn = irq_domain_alloc_named_fwnode("PCI-MSI");
264 if (fn) {
265 msi_default_domain =
266 pci_msi_create_irq_domain(fn, &pci_msi_domain_info,
267 parent);
268 }
269 if (!msi_default_domain) {
270 irq_domain_free_fwnode(fn);
271 pr_warn("failed to initialize irqdomain for MSI/MSI-x.\n");
272 } else {
273 msi_default_domain->flags |= IRQ_DOMAIN_MSI_NOMASK_QUIRK;
274 }
275 }
276
277 #ifdef CONFIG_IRQ_REMAP
278 static struct irq_chip pci_msi_ir_controller = {
279 .name = "IR-PCI-MSI",
280 .irq_unmask = pci_msi_unmask_irq,
281 .irq_mask = pci_msi_mask_irq,
282 .irq_ack = irq_chip_ack_parent,
283 .irq_retrigger = irq_chip_retrigger_hierarchy,
284 .irq_set_vcpu_affinity = irq_chip_set_vcpu_affinity_parent,
285 .flags = IRQCHIP_SKIP_SET_WAKE |
286 IRQCHIP_AFFINITY_PRE_STARTUP,
287 };
288
289 static struct msi_domain_info pci_msi_ir_domain_info = {
290 .flags = MSI_FLAG_USE_DEF_DOM_OPS | MSI_FLAG_USE_DEF_CHIP_OPS |
291 MSI_FLAG_MULTI_PCI_MSI | MSI_FLAG_PCI_MSIX,
292 .ops = &pci_msi_domain_ops,
293 .chip = &pci_msi_ir_controller,
294 .handler = handle_edge_irq,
295 .handler_name = "edge",
296 };
297
arch_create_remap_msi_irq_domain(struct irq_domain * parent,const char * name,int id)298 struct irq_domain *arch_create_remap_msi_irq_domain(struct irq_domain *parent,
299 const char *name, int id)
300 {
301 struct fwnode_handle *fn;
302 struct irq_domain *d;
303
304 fn = irq_domain_alloc_named_id_fwnode(name, id);
305 if (!fn)
306 return NULL;
307 d = pci_msi_create_irq_domain(fn, &pci_msi_ir_domain_info, parent);
308 if (!d)
309 irq_domain_free_fwnode(fn);
310 return d;
311 }
312 #endif
313
314 #ifdef CONFIG_DMAR_TABLE
dmar_msi_write_msg(struct irq_data * data,struct msi_msg * msg)315 static void dmar_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
316 {
317 dmar_msi_write(data->irq, msg);
318 }
319
320 static struct irq_chip dmar_msi_controller = {
321 .name = "DMAR-MSI",
322 .irq_unmask = dmar_msi_unmask,
323 .irq_mask = dmar_msi_mask,
324 .irq_ack = irq_chip_ack_parent,
325 .irq_set_affinity = msi_domain_set_affinity,
326 .irq_retrigger = irq_chip_retrigger_hierarchy,
327 .irq_compose_msi_msg = irq_msi_compose_msg,
328 .irq_write_msi_msg = dmar_msi_write_msg,
329 .flags = IRQCHIP_SKIP_SET_WAKE |
330 IRQCHIP_AFFINITY_PRE_STARTUP,
331 };
332
dmar_msi_get_hwirq(struct msi_domain_info * info,msi_alloc_info_t * arg)333 static irq_hw_number_t dmar_msi_get_hwirq(struct msi_domain_info *info,
334 msi_alloc_info_t *arg)
335 {
336 return arg->dmar_id;
337 }
338
dmar_msi_init(struct irq_domain * domain,struct msi_domain_info * info,unsigned int virq,irq_hw_number_t hwirq,msi_alloc_info_t * arg)339 static int dmar_msi_init(struct irq_domain *domain,
340 struct msi_domain_info *info, unsigned int virq,
341 irq_hw_number_t hwirq, msi_alloc_info_t *arg)
342 {
343 irq_domain_set_info(domain, virq, arg->dmar_id, info->chip, NULL,
344 handle_edge_irq, arg->dmar_data, "edge");
345
346 return 0;
347 }
348
349 static struct msi_domain_ops dmar_msi_domain_ops = {
350 .get_hwirq = dmar_msi_get_hwirq,
351 .msi_init = dmar_msi_init,
352 };
353
354 static struct msi_domain_info dmar_msi_domain_info = {
355 .ops = &dmar_msi_domain_ops,
356 .chip = &dmar_msi_controller,
357 };
358
dmar_get_irq_domain(void)359 static struct irq_domain *dmar_get_irq_domain(void)
360 {
361 static struct irq_domain *dmar_domain;
362 static DEFINE_MUTEX(dmar_lock);
363 struct fwnode_handle *fn;
364
365 mutex_lock(&dmar_lock);
366 if (dmar_domain)
367 goto out;
368
369 fn = irq_domain_alloc_named_fwnode("DMAR-MSI");
370 if (fn) {
371 dmar_domain = msi_create_irq_domain(fn, &dmar_msi_domain_info,
372 x86_vector_domain);
373 if (!dmar_domain)
374 irq_domain_free_fwnode(fn);
375 }
376 out:
377 mutex_unlock(&dmar_lock);
378 return dmar_domain;
379 }
380
dmar_alloc_hwirq(int id,int node,void * arg)381 int dmar_alloc_hwirq(int id, int node, void *arg)
382 {
383 struct irq_domain *domain = dmar_get_irq_domain();
384 struct irq_alloc_info info;
385
386 if (!domain)
387 return -1;
388
389 init_irq_alloc_info(&info, NULL);
390 info.type = X86_IRQ_ALLOC_TYPE_DMAR;
391 info.dmar_id = id;
392 info.dmar_data = arg;
393
394 return irq_domain_alloc_irqs(domain, 1, node, &info);
395 }
396
dmar_free_hwirq(int irq)397 void dmar_free_hwirq(int irq)
398 {
399 irq_domain_free_irqs(irq, 1);
400 }
401 #endif
402
403 /*
404 * MSI message composition
405 */
406 #ifdef CONFIG_HPET_TIMER
hpet_dev_id(struct irq_domain * domain)407 static inline int hpet_dev_id(struct irq_domain *domain)
408 {
409 struct msi_domain_info *info = msi_get_domain_info(domain);
410
411 return (int)(long)info->data;
412 }
413
hpet_msi_write_msg(struct irq_data * data,struct msi_msg * msg)414 static void hpet_msi_write_msg(struct irq_data *data, struct msi_msg *msg)
415 {
416 hpet_msi_write(irq_data_get_irq_handler_data(data), msg);
417 }
418
419 static struct irq_chip hpet_msi_controller __ro_after_init = {
420 .name = "HPET-MSI",
421 .irq_unmask = hpet_msi_unmask,
422 .irq_mask = hpet_msi_mask,
423 .irq_ack = irq_chip_ack_parent,
424 .irq_set_affinity = msi_domain_set_affinity,
425 .irq_retrigger = irq_chip_retrigger_hierarchy,
426 .irq_compose_msi_msg = irq_msi_compose_msg,
427 .irq_write_msi_msg = hpet_msi_write_msg,
428 .flags = IRQCHIP_SKIP_SET_WAKE | IRQCHIP_AFFINITY_PRE_STARTUP,
429 };
430
hpet_msi_get_hwirq(struct msi_domain_info * info,msi_alloc_info_t * arg)431 static irq_hw_number_t hpet_msi_get_hwirq(struct msi_domain_info *info,
432 msi_alloc_info_t *arg)
433 {
434 return arg->hpet_index;
435 }
436
hpet_msi_init(struct irq_domain * domain,struct msi_domain_info * info,unsigned int virq,irq_hw_number_t hwirq,msi_alloc_info_t * arg)437 static int hpet_msi_init(struct irq_domain *domain,
438 struct msi_domain_info *info, unsigned int virq,
439 irq_hw_number_t hwirq, msi_alloc_info_t *arg)
440 {
441 irq_set_status_flags(virq, IRQ_MOVE_PCNTXT);
442 irq_domain_set_info(domain, virq, arg->hpet_index, info->chip, NULL,
443 handle_edge_irq, arg->hpet_data, "edge");
444
445 return 0;
446 }
447
hpet_msi_free(struct irq_domain * domain,struct msi_domain_info * info,unsigned int virq)448 static void hpet_msi_free(struct irq_domain *domain,
449 struct msi_domain_info *info, unsigned int virq)
450 {
451 irq_clear_status_flags(virq, IRQ_MOVE_PCNTXT);
452 }
453
454 static struct msi_domain_ops hpet_msi_domain_ops = {
455 .get_hwirq = hpet_msi_get_hwirq,
456 .msi_init = hpet_msi_init,
457 .msi_free = hpet_msi_free,
458 };
459
460 static struct msi_domain_info hpet_msi_domain_info = {
461 .ops = &hpet_msi_domain_ops,
462 .chip = &hpet_msi_controller,
463 };
464
hpet_create_irq_domain(int hpet_id)465 struct irq_domain *hpet_create_irq_domain(int hpet_id)
466 {
467 struct msi_domain_info *domain_info;
468 struct irq_domain *parent, *d;
469 struct irq_alloc_info info;
470 struct fwnode_handle *fn;
471
472 if (x86_vector_domain == NULL)
473 return NULL;
474
475 domain_info = kzalloc(sizeof(*domain_info), GFP_KERNEL);
476 if (!domain_info)
477 return NULL;
478
479 *domain_info = hpet_msi_domain_info;
480 domain_info->data = (void *)(long)hpet_id;
481
482 init_irq_alloc_info(&info, NULL);
483 info.type = X86_IRQ_ALLOC_TYPE_HPET;
484 info.hpet_id = hpet_id;
485 parent = irq_remapping_get_ir_irq_domain(&info);
486 if (parent == NULL)
487 parent = x86_vector_domain;
488 else
489 hpet_msi_controller.name = "IR-HPET-MSI";
490
491 fn = irq_domain_alloc_named_id_fwnode(hpet_msi_controller.name,
492 hpet_id);
493 if (!fn) {
494 kfree(domain_info);
495 return NULL;
496 }
497
498 d = msi_create_irq_domain(fn, domain_info, parent);
499 if (!d) {
500 irq_domain_free_fwnode(fn);
501 kfree(domain_info);
502 }
503 return d;
504 }
505
hpet_assign_irq(struct irq_domain * domain,struct hpet_channel * hc,int dev_num)506 int hpet_assign_irq(struct irq_domain *domain, struct hpet_channel *hc,
507 int dev_num)
508 {
509 struct irq_alloc_info info;
510
511 init_irq_alloc_info(&info, NULL);
512 info.type = X86_IRQ_ALLOC_TYPE_HPET;
513 info.hpet_data = hc;
514 info.hpet_id = hpet_dev_id(domain);
515 info.hpet_index = dev_num;
516
517 return irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, &info);
518 }
519 #endif
520