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Merge tag 'gvt-fixes-2018-11-07' of https://github.com/intel/gvt-linux into drm-intel...
[linux-2.6-block.git] / drivers / pci / hotplug / pnv_php.c
CommitLineData
736759ef 1// SPDX-License-Identifier: GPL-2.0+
66725152
GS		 2/*
3 * PCI Hotplug Driver for PowerPC PowerNV platform.
4 *
5 * Copyright Gavin Shan, IBM Corporation 2016.
66725152
GS		 6 */
7
8#include <linux/libfdt.h>
9#include <linux/module.h>
10#include <linux/pci.h>
11#include <linux/pci_hotplug.h>
12
13#include <asm/opal.h>
14#include <asm/pnv-pci.h>
15#include <asm/ppc-pci.h>
16
17#define DRIVER_VERSION "0.1"
18#define DRIVER_AUTHOR "Gavin Shan, IBM Corporation"
19#define DRIVER_DESC "PowerPC PowerNV PCI Hotplug Driver"
20
360aebd8
GS		 21struct pnv_php_event {
22 bool added;
23 struct pnv_php_slot *php_slot;
24 struct work_struct work;
25};
26
66725152
GS		 27static LIST_HEAD(pnv_php_slot_list);
28static DEFINE_SPINLOCK(pnv_php_lock);
29
30static void pnv_php_register(struct device_node *dn);
31static void pnv_php_unregister_one(struct device_node *dn);
32static void pnv_php_unregister(struct device_node *dn);
33
49f4b08e
GS		 34static void pnv_php_disable_irq(struct pnv_php_slot *php_slot,
35 bool disable_device)
360aebd8
GS		 36{
37 struct pci_dev *pdev = php_slot->pdev;
49f4b08e 38 int irq = php_slot->irq;
360aebd8
GS		 39 u16 ctrl;
40
41 if (php_slot->irq > 0) {
42 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl);
43 ctrl &= ~(PCI_EXP_SLTCTL_HPIE |
44 PCI_EXP_SLTCTL_PDCE |
45 PCI_EXP_SLTCTL_DLLSCE);
46 pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl);
47
48 free_irq(php_slot->irq, php_slot);
49 php_slot->irq = 0;
50 }
51
52 if (php_slot->wq) {
53 destroy_workqueue(php_slot->wq);
54 php_slot->wq = NULL;
55 }
56
49f4b08e
GS		 57 if (disable_device || irq > 0) {
58 if (pdev->msix_enabled)
59 pci_disable_msix(pdev);
60 else if (pdev->msi_enabled)
61 pci_disable_msi(pdev);
62
63 pci_disable_device(pdev);
64 }
360aebd8
GS		 65}
66
66725152
GS		 67static void pnv_php_free_slot(struct kref *kref)
68{
69 struct pnv_php_slot *php_slot = container_of(kref,
70 struct pnv_php_slot, kref);
71
72 WARN_ON(!list_empty(&php_slot->children));
49f4b08e 73 pnv_php_disable_irq(php_slot, false);
66725152
GS		 74 kfree(php_slot->name);
75 kfree(php_slot);
76}
77
78static inline void pnv_php_put_slot(struct pnv_php_slot *php_slot)
79{
80
36c7c9da 81 if (!php_slot)
66725152
GS		 82 return;
83
84 kref_put(&php_slot->kref, pnv_php_free_slot);
85}
86
87static struct pnv_php_slot *pnv_php_match(struct device_node *dn,
88 struct pnv_php_slot *php_slot)
89{
90 struct pnv_php_slot *target, *tmp;
91
92 if (php_slot->dn == dn) {
93 kref_get(&php_slot->kref);
94 return php_slot;
95 }
96
97 list_for_each_entry(tmp, &php_slot->children, link) {
98 target = pnv_php_match(dn, tmp);
99 if (target)
100 return target;
101 }
102
103 return NULL;
104}
105
89379f16 106struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn)
66725152
GS		 107{
108 struct pnv_php_slot *php_slot, *tmp;
109 unsigned long flags;
110
111 spin_lock_irqsave(&pnv_php_lock, flags);
112 list_for_each_entry(tmp, &pnv_php_slot_list, link) {
113 php_slot = pnv_php_match(dn, tmp);
114 if (php_slot) {
115 spin_unlock_irqrestore(&pnv_php_lock, flags);
116 return php_slot;
117 }
118 }
119 spin_unlock_irqrestore(&pnv_php_lock, flags);
120
121 return NULL;
122}
89379f16 123EXPORT_SYMBOL_GPL(pnv_php_find_slot);
66725152
GS		 124
125/*
126 * Remove pdn for all children of the indicated device node.
127 * The function should remove pdn in a depth-first manner.
128 */
129static void pnv_php_rmv_pdns(struct device_node *dn)
130{
131 struct device_node *child;
132
133 for_each_child_of_node(dn, child) {
134 pnv_php_rmv_pdns(child);
135
136 pci_remove_device_node_info(child);
137 }
138}
139
140/*
141 * Detach all child nodes of the indicated device nodes. The
142 * function should handle device nodes in depth-first manner.
143 *
144 * We should not invoke of_node_release() as the memory for
145 * individual device node is part of large memory block. The
146 * large block is allocated from memblock (system bootup) or
147 * kmalloc() when unflattening the device tree by OF changeset.
148 * We can not free the large block allocated from memblock. For
149 * later case, it should be released at once.
150 */
151static void pnv_php_detach_device_nodes(struct device_node *parent)
152{
153 struct device_node *dn;
154 int refcount;
155
156 for_each_child_of_node(parent, dn) {
157 pnv_php_detach_device_nodes(dn);
158
159 of_node_put(dn);
2c935bc5 160 refcount = kref_read(&dn->kobj.kref);
149ba66a 161 if (refcount != 1)
b63773a8
RH		 162 pr_warn("Invalid refcount %d on <%pOF>\n",
163 refcount, dn);
66725152
GS		 164
165 of_detach_node(dn);
166 }
167}
168
169static void pnv_php_rmv_devtree(struct pnv_php_slot *php_slot)
170{
171 pnv_php_rmv_pdns(php_slot->dn);
172
173 /*
174 * Decrease the refcount if the device nodes were created
175 * through OF changeset before detaching them.
176 */
177 if (php_slot->fdt)
178 of_changeset_destroy(&php_slot->ocs);
179 pnv_php_detach_device_nodes(php_slot->dn);
180
181 if (php_slot->fdt) {
182 kfree(php_slot->dt);
183 kfree(php_slot->fdt);
184 php_slot->dt = NULL;
185 php_slot->dn->child = NULL;
186 php_slot->fdt = NULL;
187 }
188}
189
190/*
191 * As the nodes in OF changeset are applied in reverse order, we
192 * need revert the nodes in advance so that we have correct node
193 * order after the changeset is applied.
194 */
195static void pnv_php_reverse_nodes(struct device_node *parent)
196{
197 struct device_node *child, *next;
198
199 /* In-depth first */
200 for_each_child_of_node(parent, child)
201 pnv_php_reverse_nodes(child);
202
203 /* Reverse the nodes in the child list */
204 child = parent->child;
205 parent->child = NULL;
206 while (child) {
207 next = child->sibling;
208
209 child->sibling = parent->child;
210 parent->child = child;
211 child = next;
212 }
213}
214
215static int pnv_php_populate_changeset(struct of_changeset *ocs,
216 struct device_node *dn)
217{
218 struct device_node *child;
219 int ret = 0;
220
221 for_each_child_of_node(dn, child) {
222 ret = of_changeset_attach_node(ocs, child);
5d9c6b8a
JL		 223 if (ret) {
224 of_node_put(child);
66725152 225 break;
5d9c6b8a 226 }
66725152
GS		 227
228 ret = pnv_php_populate_changeset(ocs, child);
5d9c6b8a
JL		 229 if (ret) {
230 of_node_put(child);
66725152 231 break;
5d9c6b8a 232 }
66725152
GS		 233 }
234
235 return ret;
236}
237
238static void *pnv_php_add_one_pdn(struct device_node *dn, void *data)
239{
240 struct pci_controller *hose = (struct pci_controller *)data;
241 struct pci_dn *pdn;
242
243 pdn = pci_add_device_node_info(hose, dn);
149ba66a 244 if (!pdn)
66725152
GS		 245 return ERR_PTR(-ENOMEM);
246
247 return NULL;
248}
249
250static void pnv_php_add_pdns(struct pnv_php_slot *slot)
251{
252 struct pci_controller *hose = pci_bus_to_host(slot->bus);
253
254 pci_traverse_device_nodes(slot->dn, pnv_php_add_one_pdn, hose);
255}
256
257static int pnv_php_add_devtree(struct pnv_php_slot *php_slot)
258{
259 void *fdt, *fdt1, *dt;
260 int ret;
261
262 /* We don't know the FDT blob size. We try to get it through
263 * maximal memory chunk and then copy it to another chunk that
264 * fits the real size.
265 */
266 fdt1 = kzalloc(0x10000, GFP_KERNEL);
149ba66a 267 if (!fdt1) {
66725152 268 ret = -ENOMEM;
66725152
GS		 269 goto out;
270 }
271
272 ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000);
149ba66a 273 if (ret) {
7506dc79 274 pci_warn(php_slot->pdev, "Error %d getting FDT blob\n", ret);
66725152
GS		 275 goto free_fdt1;
276 }
277
74171e9d 278 fdt = kmemdup(fdt1, fdt_totalsize(fdt1), GFP_KERNEL);
149ba66a 279 if (!fdt) {
66725152 280 ret = -ENOMEM;
66725152
GS		 281 goto free_fdt1;
282 }
283
284 /* Unflatten device tree blob */
66725152 285 dt = of_fdt_unflatten_tree(fdt, php_slot->dn, NULL);
149ba66a 286 if (!dt) {
66725152 287 ret = -EINVAL;
7506dc79 288 pci_warn(php_slot->pdev, "Cannot unflatten FDT\n");
66725152
GS		 289 goto free_fdt;
290 }
291
292 /* Initialize and apply the changeset */
293 of_changeset_init(&php_slot->ocs);
294 pnv_php_reverse_nodes(php_slot->dn);
295 ret = pnv_php_populate_changeset(&php_slot->ocs, php_slot->dn);
149ba66a 296 if (ret) {
66725152 297 pnv_php_reverse_nodes(php_slot->dn);
7506dc79 298 pci_warn(php_slot->pdev, "Error %d populating changeset\n",
66725152
GS		 299 ret);
300 goto free_dt;
301 }
302
303 php_slot->dn->child = NULL;
304 ret = of_changeset_apply(&php_slot->ocs);
149ba66a 305 if (ret) {
7506dc79 306 pci_warn(php_slot->pdev, "Error %d applying changeset\n", ret);
66725152
GS		 307 goto destroy_changeset;
308 }
309
310 /* Add device node firmware data */
311 pnv_php_add_pdns(php_slot);
312 php_slot->fdt = fdt;
313 php_slot->dt = dt;
314 kfree(fdt1);
315 goto out;
316
317destroy_changeset:
318 of_changeset_destroy(&php_slot->ocs);
319free_dt:
320 kfree(dt);
321 php_slot->dn->child = NULL;
322free_fdt:
323 kfree(fdt);
324free_fdt1:
325 kfree(fdt1);
326out:
327 return ret;
328}
329
a7da2161
LW		 330static inline struct pnv_php_slot *to_pnv_php_slot(struct hotplug_slot *slot)
331{
332 return container_of(slot, struct pnv_php_slot, slot);
333}
334
89379f16
AD		 335int pnv_php_set_slot_power_state(struct hotplug_slot *slot,
336 uint8_t state)
66725152 337{
125450f8 338 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
66725152
GS		 339 struct opal_msg msg;
340 int ret;
341
342 ret = pnv_pci_set_power_state(php_slot->id, state, &msg);
149ba66a 343 if (ret > 0) {
66725152
GS		 344 if (be64_to_cpu(msg.params[1]) != php_slot->dn->phandle ||
345 be64_to_cpu(msg.params[2]) != state ||
346 be64_to_cpu(msg.params[3]) != OPAL_SUCCESS) {
7506dc79 347 pci_warn(php_slot->pdev, "Wrong msg (%lld, %lld, %lld)\n",
66725152
GS		 348 be64_to_cpu(msg.params[1]),
349 be64_to_cpu(msg.params[2]),
350 be64_to_cpu(msg.params[3]));
351 return -ENOMSG;
352 }
149ba66a 353 } else if (ret < 0) {
7506dc79 354 pci_warn(php_slot->pdev, "Error %d powering %s\n",
66725152
GS		 355 ret, (state == OPAL_PCI_SLOT_POWER_ON) ? "on" : "off");
356 return ret;
357 }
358
5473a6bf 359 if (state == OPAL_PCI_SLOT_POWER_OFF || state == OPAL_PCI_SLOT_OFFLINE)
66725152
GS		 360 pnv_php_rmv_devtree(php_slot);
361 else
362 ret = pnv_php_add_devtree(php_slot);
363
364 return ret;
365}
89379f16 366EXPORT_SYMBOL_GPL(pnv_php_set_slot_power_state);
66725152
GS		 367
368static int pnv_php_get_power_state(struct hotplug_slot *slot, u8 *state)
369{
125450f8 370 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
66725152
GS		 371 uint8_t power_state = OPAL_PCI_SLOT_POWER_ON;
372 int ret;
373
374 /*
375 * Retrieve power status from firmware. If we fail
376 * getting that, the power status fails back to
377 * be on.
378 */
379 ret = pnv_pci_get_power_state(php_slot->id, &power_state);
149ba66a 380 if (ret) {
7506dc79 381 pci_warn(php_slot->pdev, "Error %d getting power status\n",
66725152
GS		 382 ret);
383 } else {
384 *state = power_state;
66725152
GS		 385 }
386
387 return 0;
388}
389
390static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state)
391{
125450f8 392 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
66725152
GS		 393 uint8_t presence = OPAL_PCI_SLOT_EMPTY;
394 int ret;
395
396 /*
397 * Retrieve presence status from firmware. If we can't
398 * get that, it will fail back to be empty.
399 */
400 ret = pnv_pci_get_presence_state(php_slot->id, &presence);
149ba66a 401 if (ret >= 0) {
66725152 402 *state = presence;
66725152
GS		 403 ret = 0;
404 } else {
7506dc79 405 pci_warn(php_slot->pdev, "Error %d getting presence\n", ret);
66725152
GS		 406 }
407
408 return ret;
409}
410
a7da2161
LW		 411static int pnv_php_get_attention_state(struct hotplug_slot *slot, u8 *state)
412{
413 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
414
415 *state = php_slot->attention_state;
416 return 0;
417}
418
66725152
GS		 419static int pnv_php_set_attention_state(struct hotplug_slot *slot, u8 state)
420{
a7da2161
LW		 421 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
422
66725152 423 /* FIXME: Make it real once firmware supports it */
a7da2161 424 php_slot->attention_state = state;
66725152
GS		 425
426 return 0;
427}
428
429static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan)
430{
431 struct hotplug_slot *slot = &php_slot->slot;
432 uint8_t presence = OPAL_PCI_SLOT_EMPTY;
433 uint8_t power_status = OPAL_PCI_SLOT_POWER_ON;
434 int ret;
435
436 /* Check if the slot has been configured */
437 if (php_slot->state != PNV_PHP_STATE_REGISTERED)
438 return 0;
439
440 /* Retrieve slot presence status */
441 ret = pnv_php_get_adapter_state(slot, &presence);
149ba66a 442 if (ret)
66725152
GS		 443 return ret;
444
d0c42497
GS		 445 /*
446 * Proceed if there have nothing behind the slot. However,
447 * we should leave the slot in registered state at the
448 * beginning. Otherwise, the PCI devices inserted afterwards
449 * won't be probed and populated.
450 */
451 if (presence == OPAL_PCI_SLOT_EMPTY) {
452 if (!php_slot->power_state_check) {
453 php_slot->power_state_check = true;
454
455 return 0;
456 }
457
66725152 458 goto scan;
d0c42497 459 }
66725152
GS		 460
461 /*
462 * If the power supply to the slot is off, we can't detect
463 * adapter presence state. That means we have to turn the
464 * slot on before going to probe slot's presence state.
465 *
466 * On the first time, we don't change the power status to
467 * boost system boot with assumption that the firmware
468 * supplies consistent slot power status: empty slot always
469 * has its power off and non-empty slot has its power on.
470 */
471 if (!php_slot->power_state_check) {
472 php_slot->power_state_check = true;
473
474 ret = pnv_php_get_power_state(slot, &power_status);
149ba66a 475 if (ret)
66725152
GS		 476 return ret;
477
478 if (power_status != OPAL_PCI_SLOT_POWER_ON)
479 return 0;
480 }
481
482 /* Check the power status. Scan the slot if it is already on */
483 ret = pnv_php_get_power_state(slot, &power_status);
149ba66a 484 if (ret)
66725152
GS		 485 return ret;
486
487 if (power_status == OPAL_PCI_SLOT_POWER_ON)
488 goto scan;
489
490 /* Power is off, turn it on and then scan the slot */
491 ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_ON);
149ba66a 492 if (ret)
66725152
GS		 493 return ret;
494
495scan:
496 if (presence == OPAL_PCI_SLOT_PRESENT) {
497 if (rescan) {
498 pci_lock_rescan_remove();
499 pci_hp_add_devices(php_slot->bus);
500 pci_unlock_rescan_remove();
501 }
502
503 /* Rescan for child hotpluggable slots */
504 php_slot->state = PNV_PHP_STATE_POPULATED;
505 if (rescan)
506 pnv_php_register(php_slot->dn);
507 } else {
508 php_slot->state = PNV_PHP_STATE_POPULATED;
509 }
510
511 return 0;
512}
513
514static int pnv_php_enable_slot(struct hotplug_slot *slot)
515{
a7da2161 516 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
66725152
GS		 517
518 return pnv_php_enable(php_slot, true);
519}
520
521static int pnv_php_disable_slot(struct hotplug_slot *slot)
522{
125450f8 523 struct pnv_php_slot *php_slot = to_pnv_php_slot(slot);
66725152
GS		 524 int ret;
525
526 if (php_slot->state != PNV_PHP_STATE_POPULATED)
527 return 0;
528
529 /* Remove all devices behind the slot */
530 pci_lock_rescan_remove();
531 pci_hp_remove_devices(php_slot->bus);
532 pci_unlock_rescan_remove();
533
534 /* Detach the child hotpluggable slots */
535 pnv_php_unregister(php_slot->dn);
536
537 /* Notify firmware and remove device nodes */
538 ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_OFF);
539
540 php_slot->state = PNV_PHP_STATE_REGISTERED;
541 return ret;
542}
543
81c4b5bf 544static const struct hotplug_slot_ops php_slot_ops = {
66725152
GS		 545 .get_power_status = pnv_php_get_power_state,
546 .get_adapter_status = pnv_php_get_adapter_state,
a7da2161 547 .get_attention_status = pnv_php_get_attention_state,
66725152
GS		 548 .set_attention_status = pnv_php_set_attention_state,
549 .enable_slot = pnv_php_enable_slot,
550 .disable_slot = pnv_php_disable_slot,
551};
552
51bbf9be 553static void pnv_php_release(struct pnv_php_slot *php_slot)
66725152 554{
66725152
GS		 555 unsigned long flags;
556
557 /* Remove from global or child list */
558 spin_lock_irqsave(&pnv_php_lock, flags);
559 list_del(&php_slot->link);
560 spin_unlock_irqrestore(&pnv_php_lock, flags);
561
562 /* Detach from parent */
563 pnv_php_put_slot(php_slot);
564 pnv_php_put_slot(php_slot->parent);
565}
566
567static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn)
568{
569 struct pnv_php_slot *php_slot;
570 struct pci_bus *bus;
571 const char *label;
572 uint64_t id;
39f0d6fb 573 int ret;
66725152 574
39f0d6fb
GS		 575 ret = of_property_read_string(dn, "ibm,slot-label", &label);
576 if (ret)
66725152
GS		 577 return NULL;
578
579 if (pnv_pci_get_slot_id(dn, &id))
580 return NULL;
581
582 bus = pci_find_bus_by_node(dn);
149ba66a 583 if (!bus)
66725152
GS		 584 return NULL;
585
586 php_slot = kzalloc(sizeof(*php_slot), GFP_KERNEL);
149ba66a 587 if (!php_slot)
66725152
GS		 588 return NULL;
589
590 php_slot->name = kstrdup(label, GFP_KERNEL);
149ba66a 591 if (!php_slot->name) {
66725152
GS		 592 kfree(php_slot);
593 return NULL;
594 }
595
149ba66a 596 if (dn->child && PCI_DN(dn->child))
66725152
GS		 597 php_slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn);
598 else
599 php_slot->slot_no = -1; /* Placeholder slot */
600
601 kref_init(&php_slot->kref);
602 php_slot->state = PNV_PHP_STATE_INITIALIZED;
603 php_slot->dn = dn;
604 php_slot->pdev = bus->self;
605 php_slot->bus = bus;
606 php_slot->id = id;
607 php_slot->power_state_check = false;
608 php_slot->slot.ops = &php_slot_ops;
66725152
GS		 609
610 INIT_LIST_HEAD(&php_slot->children);
611 INIT_LIST_HEAD(&php_slot->link);
612
613 return php_slot;
614}
615
616static int pnv_php_register_slot(struct pnv_php_slot *php_slot)
617{
618 struct pnv_php_slot *parent;
619 struct device_node *dn = php_slot->dn;
620 unsigned long flags;
621 int ret;
622
623 /* Check if the slot is registered or not */
624 parent = pnv_php_find_slot(php_slot->dn);
149ba66a 625 if (parent) {
66725152
GS		 626 pnv_php_put_slot(parent);
627 return -EEXIST;
628 }
629
630 /* Register PCI slot */
631 ret = pci_hp_register(&php_slot->slot, php_slot->bus,
632 php_slot->slot_no, php_slot->name);
149ba66a 633 if (ret) {
7506dc79 634 pci_warn(php_slot->pdev, "Error %d registering slot\n", ret);
66725152
GS		 635 return ret;
636 }
637
638 /* Attach to the parent's child list or global list */
639 while ((dn = of_get_parent(dn))) {
640 if (!PCI_DN(dn)) {
641 of_node_put(dn);
642 break;
643 }
644
645 parent = pnv_php_find_slot(dn);
646 if (parent) {
647 of_node_put(dn);
648 break;
649 }
650
651 of_node_put(dn);
652 }
653
654 spin_lock_irqsave(&pnv_php_lock, flags);
655 php_slot->parent = parent;
656 if (parent)
657 list_add_tail(&php_slot->link, &parent->children);
658 else
659 list_add_tail(&php_slot->link, &pnv_php_slot_list);
660 spin_unlock_irqrestore(&pnv_php_lock, flags);
661
662 php_slot->state = PNV_PHP_STATE_REGISTERED;
663 return 0;
664}
665
360aebd8
GS		 666static int pnv_php_enable_msix(struct pnv_php_slot *php_slot)
667{
668 struct pci_dev *pdev = php_slot->pdev;
669 struct msix_entry entry;
670 int nr_entries, ret;
671 u16 pcie_flag;
672
673 /* Get total number of MSIx entries */
674 nr_entries = pci_msix_vec_count(pdev);
675 if (nr_entries < 0)
676 return nr_entries;
677
678 /* Check hotplug MSIx entry is in range */
679 pcie_capability_read_word(pdev, PCI_EXP_FLAGS, &pcie_flag);
680 entry.entry = (pcie_flag & PCI_EXP_FLAGS_IRQ) >> 9;
681 if (entry.entry >= nr_entries)
682 return -ERANGE;
683
684 /* Enable MSIx */
685 ret = pci_enable_msix_exact(pdev, &entry, 1);
686 if (ret) {
7506dc79 687 pci_warn(pdev, "Error %d enabling MSIx\n", ret);
360aebd8
GS		 688 return ret;
689 }
690
691 return entry.vector;
692}
693
694static void pnv_php_event_handler(struct work_struct *work)
695{
696 struct pnv_php_event *event =
697 container_of(work, struct pnv_php_event, work);
698 struct pnv_php_slot *php_slot = event->php_slot;
699
700 if (event->added)
701 pnv_php_enable_slot(&php_slot->slot);
702 else
703 pnv_php_disable_slot(&php_slot->slot);
704
705 kfree(event);
706}
707
708static irqreturn_t pnv_php_interrupt(int irq, void *data)
709{
710 struct pnv_php_slot *php_slot = data;
711 struct pci_dev *pchild, *pdev = php_slot->pdev;
712 struct eeh_dev *edev;
713 struct eeh_pe *pe;
714 struct pnv_php_event *event;
715 u16 sts, lsts;
716 u8 presence;
717 bool added;
718 unsigned long flags;
719 int ret;
720
721 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts);
722 sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
723 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts);
724 if (sts & PCI_EXP_SLTSTA_DLLSC) {
725 pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lsts);
726 added = !!(lsts & PCI_EXP_LNKSTA_DLLLA);
454593e5
GS		 727 } else if (!(php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) &&
728 (sts & PCI_EXP_SLTSTA_PDC)) {
360aebd8 729 ret = pnv_pci_get_presence_state(php_slot->id, &presence);
d7d55536 730 if (ret) {
7506dc79 731 pci_warn(pdev, "PCI slot [%s] error %d getting presence (0x%04x), to retry the operation.\n",
d7d55536 732 php_slot->name, ret, sts);
360aebd8 733 return IRQ_HANDLED;
d7d55536
GS		 734 }
735
360aebd8
GS		 736 added = !!(presence == OPAL_PCI_SLOT_PRESENT);
737 } else {
738 return IRQ_NONE;
739 }
740
741 /* Freeze the removed PE to avoid unexpected error reporting */
742 if (!added) {
743 pchild = list_first_entry_or_null(&php_slot->bus->devices,
744 struct pci_dev, bus_list);
745 edev = pchild ? pci_dev_to_eeh_dev(pchild) : NULL;
746 pe = edev ? edev->pe : NULL;
747 if (pe) {
748 eeh_serialize_lock(&flags);
e762bb89 749 eeh_pe_mark_isolated(pe);
360aebd8
GS		 750 eeh_serialize_unlock(flags);
751 eeh_pe_set_option(pe, EEH_OPT_FREEZE_PE);
752 }
753 }
754
755 /*
756 * The PE is left in frozen state if the event is missed. It's
757 * fine as the PCI devices (PE) aren't functional any more.
758 */
759 event = kzalloc(sizeof(*event), GFP_ATOMIC);
760 if (!event) {
7506dc79 761 pci_warn(pdev, "PCI slot [%s] missed hotplug event 0x%04x\n",
360aebd8
GS		 762 php_slot->name, sts);
763 return IRQ_HANDLED;
764 }
765
7506dc79 766 pci_info(pdev, "PCI slot [%s] %s (IRQ: %d)\n",
360aebd8
GS		 767 php_slot->name, added ? "added" : "removed", irq);
768 INIT_WORK(&event->work, pnv_php_event_handler);
769 event->added = added;
770 event->php_slot = php_slot;
771 queue_work(php_slot->wq, &event->work);
772
773 return IRQ_HANDLED;
774}
775
776static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq)
777{
778 struct pci_dev *pdev = php_slot->pdev;
454593e5 779 u32 broken_pdc = 0;
360aebd8
GS		 780 u16 sts, ctrl;
781 int ret;
782
783 /* Allocate workqueue */
784 php_slot->wq = alloc_workqueue("pciehp-%s", 0, 0, php_slot->name);
785 if (!php_slot->wq) {
7506dc79 786 pci_warn(pdev, "Cannot alloc workqueue\n");
49f4b08e 787 pnv_php_disable_irq(php_slot, true);
360aebd8
GS		 788 return;
789 }
790
454593e5
GS		 791 /* Check PDC (Presence Detection Change) is broken or not */
792 ret = of_property_read_u32(php_slot->dn, "ibm,slot-broken-pdc",
793 &broken_pdc);
794 if (!ret && broken_pdc)
795 php_slot->flags |= PNV_PHP_FLAG_BROKEN_PDC;
796
360aebd8
GS		 797 /* Clear pending interrupts */
798 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts);
454593e5
GS		 799 if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC)
800 sts |= PCI_EXP_SLTSTA_DLLSC;
801 else
802 sts |= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
360aebd8
GS		 803 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts);
804
805 /* Request the interrupt */
806 ret = request_irq(irq, pnv_php_interrupt, IRQF_SHARED,
807 php_slot->name, php_slot);
808 if (ret) {
49f4b08e 809 pnv_php_disable_irq(php_slot, true);
7506dc79 810 pci_warn(pdev, "Error %d enabling IRQ %d\n", ret, irq);
360aebd8
GS		 811 return;
812 }
813
814 /* Enable the interrupts */
815 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl);
454593e5
GS		 816 if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) {
817 ctrl &= ~PCI_EXP_SLTCTL_PDCE;
818 ctrl |= (PCI_EXP_SLTCTL_HPIE |
819 PCI_EXP_SLTCTL_DLLSCE);
820 } else {
821 ctrl |= (PCI_EXP_SLTCTL_HPIE |
822 PCI_EXP_SLTCTL_PDCE |
823 PCI_EXP_SLTCTL_DLLSCE);
824 }
360aebd8
GS		 825 pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl);
826
827 /* The interrupt is initialized successfully when @irq is valid */
828 php_slot->irq = irq;
829}
830
831static void pnv_php_enable_irq(struct pnv_php_slot *php_slot)
832{
833 struct pci_dev *pdev = php_slot->pdev;
834 int irq, ret;
835
303529d6
GS		 836 /*
837 * The MSI/MSIx interrupt might have been occupied by other
838 * drivers. Don't populate the surprise hotplug capability
839 * in that case.
840 */
841 if (pci_dev_msi_enabled(pdev))
842 return;
843
360aebd8
GS		 844 ret = pci_enable_device(pdev);
845 if (ret) {
7506dc79 846 pci_warn(pdev, "Error %d enabling device\n", ret);
360aebd8
GS		 847 return;
848 }
849
850 pci_set_master(pdev);
851
852 /* Enable MSIx interrupt */
853 irq = pnv_php_enable_msix(php_slot);
854 if (irq > 0) {
855 pnv_php_init_irq(php_slot, irq);
856 return;
857 }
858
859 /*
860 * Use MSI if MSIx doesn't work. Fail back to legacy INTx
861 * if MSI doesn't work either
862 */
863 ret = pci_enable_msi(pdev);
864 if (!ret || pdev->irq) {
865 irq = pdev->irq;
866 pnv_php_init_irq(php_slot, irq);
867 }
868}
869
66725152
GS		 870static int pnv_php_register_one(struct device_node *dn)
871{
872 struct pnv_php_slot *php_slot;
39f0d6fb 873 u32 prop32;
66725152
GS		 874 int ret;
875
876 /* Check if it's hotpluggable slot */
39f0d6fb
GS		 877 ret = of_property_read_u32(dn, "ibm,slot-pluggable", &prop32);
878 if (ret || !prop32)
66725152
GS		 879 return -ENXIO;
880
39f0d6fb
GS		 881 ret = of_property_read_u32(dn, "ibm,reset-by-firmware", &prop32);
882 if (ret || !prop32)
66725152
GS		 883 return -ENXIO;
884
885 php_slot = pnv_php_alloc_slot(dn);
149ba66a 886 if (!php_slot)
66725152
GS		 887 return -ENODEV;
888
889 ret = pnv_php_register_slot(php_slot);
149ba66a 890 if (ret)
66725152
GS		 891 goto free_slot;
892
893 ret = pnv_php_enable(php_slot, false);
149ba66a 894 if (ret)
66725152
GS		 895 goto unregister_slot;
896
360aebd8 897 /* Enable interrupt if the slot supports surprise hotplug */
39f0d6fb
GS		 898 ret = of_property_read_u32(dn, "ibm,slot-surprise-pluggable", &prop32);
899 if (!ret && prop32)
360aebd8
GS		 900 pnv_php_enable_irq(php_slot);
901
66725152
GS		 902 return 0;
903
904unregister_slot:
905 pnv_php_unregister_one(php_slot->dn);
906free_slot:
907 pnv_php_put_slot(php_slot);
908 return ret;
909}
910
911static void pnv_php_register(struct device_node *dn)
912{
913 struct device_node *child;
914
915 /*
916 * The parent slots should be registered before their
917 * child slots.
918 */
919 for_each_child_of_node(dn, child) {
920 pnv_php_register_one(child);
921 pnv_php_register(child);
922 }
923}
924
925static void pnv_php_unregister_one(struct device_node *dn)
926{
927 struct pnv_php_slot *php_slot;
928
929 php_slot = pnv_php_find_slot(dn);
930 if (!php_slot)
931 return;
932
933 php_slot->state = PNV_PHP_STATE_OFFLINE;
66725152 934 pci_hp_deregister(&php_slot->slot);
51bbf9be 935 pnv_php_release(php_slot);
97c6f25d 936 pnv_php_put_slot(php_slot);
66725152
GS		 937}
938
939static void pnv_php_unregister(struct device_node *dn)
940{
941 struct device_node *child;
942
943 /* The child slots should go before their parent slots */
944 for_each_child_of_node(dn, child) {
945 pnv_php_unregister(child);
946 pnv_php_unregister_one(child);
947 }
948}
949
950static int __init pnv_php_init(void)
951{
952 struct device_node *dn;
953
954 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
955 for_each_compatible_node(dn, NULL, "ibm,ioda2-phb")
956 pnv_php_register(dn);
957
958 return 0;
959}
960
961static void __exit pnv_php_exit(void)
962{
963 struct device_node *dn;
964
965 for_each_compatible_node(dn, NULL, "ibm,ioda2-phb")
966 pnv_php_unregister(dn);
967}
968
969module_init(pnv_php_init);
970module_exit(pnv_php_exit);
971
972MODULE_VERSION(DRIVER_VERSION);
973MODULE_LICENSE("GPL v2");
974MODULE_AUTHOR(DRIVER_AUTHOR);
975MODULE_DESCRIPTION(DRIVER_DESC);
Linux 6.x block layer and io_uring tree(s)