1 // SPDX-License-Identifier: GPL-2.0+
3 * CompactPCI Hot Plug Driver
5 * Copyright (C) 2002,2005 SOMA Networks, Inc.
6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
7 * Copyright (C) 2001 IBM Corp.
11 * Send feedback to <scottm@somanetworks.com>
14 #include <linux/module.h>
15 #include <linux/kernel.h>
16 #include <linux/sched/signal.h>
17 #include <linux/slab.h>
18 #include <linux/pci.h>
19 #include <linux/pci_hotplug.h>
20 #include <linux/init.h>
21 #include <linux/interrupt.h>
22 #include <linux/atomic.h>
23 #include <linux/delay.h>
24 #include <linux/kthread.h>
25 #include "cpci_hotplug.h"
27 #define DRIVER_AUTHOR "Scott Murray <scottm@somanetworks.com>"
28 #define DRIVER_DESC "CompactPCI Hot Plug Core"
30 #define MY_NAME "cpci_hotplug"
32 #define dbg(format, arg...) \
35 printk(KERN_DEBUG "%s: " format "\n", \
38 #define err(format, arg...) printk(KERN_ERR "%s: " format "\n", MY_NAME, ## arg)
39 #define info(format, arg...) printk(KERN_INFO "%s: " format "\n", MY_NAME, ## arg)
40 #define warn(format, arg...) printk(KERN_WARNING "%s: " format "\n", MY_NAME, ## arg)
43 static DECLARE_RWSEM(list_rwsem);
44 static LIST_HEAD(slot_list);
46 static atomic_t extracting;
48 static struct cpci_hp_controller *controller;
49 static struct task_struct *cpci_thread;
50 static int thread_finished;
52 static int enable_slot(struct hotplug_slot *slot);
53 static int disable_slot(struct hotplug_slot *slot);
54 static int set_attention_status(struct hotplug_slot *slot, u8 value);
55 static int get_power_status(struct hotplug_slot *slot, u8 *value);
56 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
57 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
58 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
60 static struct hotplug_slot_ops cpci_hotplug_slot_ops = {
61 .enable_slot = enable_slot,
62 .disable_slot = disable_slot,
63 .set_attention_status = set_attention_status,
64 .get_power_status = get_power_status,
65 .get_attention_status = get_attention_status,
66 .get_adapter_status = get_adapter_status,
67 .get_latch_status = get_latch_status,
71 update_latch_status(struct hotplug_slot *hotplug_slot, u8 value)
73 struct hotplug_slot_info info;
75 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
76 info.latch_status = value;
77 return pci_hp_change_slot_info(hotplug_slot, &info);
81 update_adapter_status(struct hotplug_slot *hotplug_slot, u8 value)
83 struct hotplug_slot_info info;
85 memcpy(&info, hotplug_slot->info, sizeof(struct hotplug_slot_info));
86 info.adapter_status = value;
87 return pci_hp_change_slot_info(hotplug_slot, &info);
91 enable_slot(struct hotplug_slot *hotplug_slot)
93 struct slot *slot = hotplug_slot->private;
96 dbg("%s - physical_slot = %s", __func__, slot_name(slot));
98 if (controller->ops->set_power)
99 retval = controller->ops->set_power(slot, 1);
104 disable_slot(struct hotplug_slot *hotplug_slot)
106 struct slot *slot = hotplug_slot->private;
109 dbg("%s - physical_slot = %s", __func__, slot_name(slot));
111 down_write(&list_rwsem);
113 /* Unconfigure device */
114 dbg("%s - unconfiguring slot %s", __func__, slot_name(slot));
115 retval = cpci_unconfigure_slot(slot);
117 err("%s - could not unconfigure slot %s",
118 __func__, slot_name(slot));
121 dbg("%s - finished unconfiguring slot %s", __func__, slot_name(slot));
123 /* Clear EXT (by setting it) */
124 if (cpci_clear_ext(slot)) {
125 err("%s - could not clear EXT for slot %s",
126 __func__, slot_name(slot));
132 if (controller->ops->set_power) {
133 retval = controller->ops->set_power(slot, 0);
138 if (update_adapter_status(slot->hotplug_slot, 0))
139 warn("failure to update adapter file");
141 if (slot->extracting) {
142 slot->extracting = 0;
143 atomic_dec(&extracting);
146 up_write(&list_rwsem);
151 cpci_get_power_status(struct slot *slot)
155 if (controller->ops->get_power)
156 power = controller->ops->get_power(slot);
161 get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
163 struct slot *slot = hotplug_slot->private;
165 *value = cpci_get_power_status(slot);
170 get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
172 struct slot *slot = hotplug_slot->private;
174 *value = cpci_get_attention_status(slot);
179 set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
181 return cpci_set_attention_status(hotplug_slot->private, status);
185 get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
187 *value = hotplug_slot->info->adapter_status;
192 get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
194 *value = hotplug_slot->info->latch_status;
198 static void release_slot(struct hotplug_slot *hotplug_slot)
200 struct slot *slot = hotplug_slot->private;
202 kfree(slot->hotplug_slot->info);
203 kfree(slot->hotplug_slot);
204 pci_dev_put(slot->dev);
208 #define SLOT_NAME_SIZE 6
211 cpci_hp_register_bus(struct pci_bus *bus, u8 first, u8 last)
214 struct hotplug_slot *hotplug_slot;
215 struct hotplug_slot_info *info;
216 char name[SLOT_NAME_SIZE];
220 if (!(controller && bus))
224 * Create a structure for each slot, and register that slot
225 * with the pci_hotplug subsystem.
227 for (i = first; i <= last; ++i) {
228 slot = kzalloc(sizeof(struct slot), GFP_KERNEL);
235 kzalloc(sizeof(struct hotplug_slot), GFP_KERNEL);
240 slot->hotplug_slot = hotplug_slot;
242 info = kzalloc(sizeof(struct hotplug_slot_info), GFP_KERNEL);
247 hotplug_slot->info = info;
251 slot->devfn = PCI_DEVFN(i, 0);
253 snprintf(name, SLOT_NAME_SIZE, "%02x:%02x", bus->number, i);
255 hotplug_slot->private = slot;
256 hotplug_slot->release = &release_slot;
257 hotplug_slot->ops = &cpci_hotplug_slot_ops;
260 * Initialize the slot info structure with some known
263 dbg("initializing slot %s", name);
264 info->power_status = cpci_get_power_status(slot);
265 info->attention_status = cpci_get_attention_status(slot);
267 dbg("registering slot %s", name);
268 status = pci_hp_register(slot->hotplug_slot, bus, i, name);
270 err("pci_hp_register failed with error %d", status);
273 dbg("slot registered with name: %s", slot_name(slot));
275 /* Add slot to our internal list */
276 down_write(&list_rwsem);
277 list_add(&slot->slot_list, &slot_list);
279 up_write(&list_rwsem);
291 EXPORT_SYMBOL_GPL(cpci_hp_register_bus);
294 cpci_hp_unregister_bus(struct pci_bus *bus)
300 down_write(&list_rwsem);
302 up_write(&list_rwsem);
305 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
306 if (slot->bus == bus) {
307 list_del(&slot->slot_list);
310 dbg("deregistering slot %s", slot_name(slot));
311 status = pci_hp_deregister(slot->hotplug_slot);
313 err("pci_hp_deregister failed with error %d",
319 up_write(&list_rwsem);
322 EXPORT_SYMBOL_GPL(cpci_hp_unregister_bus);
324 /* This is the interrupt mode interrupt handler */
326 cpci_hp_intr(int irq, void *data)
328 dbg("entered cpci_hp_intr");
330 /* Check to see if it was our interrupt */
331 if ((controller->irq_flags & IRQF_SHARED) &&
332 !controller->ops->check_irq(controller->dev_id)) {
333 dbg("exited cpci_hp_intr, not our interrupt");
337 /* Disable ENUM interrupt */
338 controller->ops->disable_irq();
340 /* Trigger processing by the event thread */
341 wake_up_process(cpci_thread);
346 * According to PICMG 2.1 R2.0, section 6.3.2, upon
347 * initialization, the system driver shall clear the
348 * INS bits of the cold-inserted devices.
351 init_slots(int clear_ins)
356 dbg("%s - enter", __func__);
357 down_read(&list_rwsem);
359 up_read(&list_rwsem);
362 list_for_each_entry(slot, &slot_list, slot_list) {
363 dbg("%s - looking at slot %s", __func__, slot_name(slot));
364 if (clear_ins && cpci_check_and_clear_ins(slot))
365 dbg("%s - cleared INS for slot %s",
366 __func__, slot_name(slot));
367 dev = pci_get_slot(slot->bus, PCI_DEVFN(slot->number, 0));
369 if (update_adapter_status(slot->hotplug_slot, 1))
370 warn("failure to update adapter file");
371 if (update_latch_status(slot->hotplug_slot, 1))
372 warn("failure to update latch file");
376 up_read(&list_rwsem);
377 dbg("%s - exit", __func__);
389 down_read(&list_rwsem);
391 up_read(&list_rwsem);
392 err("no slots registered, shutting down");
395 extracted = inserted = 0;
396 list_for_each_entry(slot, &slot_list, slot_list) {
397 dbg("%s - looking at slot %s", __func__, slot_name(slot));
398 if (cpci_check_and_clear_ins(slot)) {
400 * Some broken hardware (e.g. PLX 9054AB) asserts
404 warn("slot %s already inserted",
410 /* Process insertion */
411 dbg("%s - slot %s inserted", __func__, slot_name(slot));
414 hs_csr = cpci_get_hs_csr(slot);
415 dbg("%s - slot %s HS_CSR (1) = %04x",
416 __func__, slot_name(slot), hs_csr);
418 /* Configure device */
419 dbg("%s - configuring slot %s",
420 __func__, slot_name(slot));
421 if (cpci_configure_slot(slot)) {
422 err("%s - could not configure slot %s",
423 __func__, slot_name(slot));
426 dbg("%s - finished configuring slot %s",
427 __func__, slot_name(slot));
430 hs_csr = cpci_get_hs_csr(slot);
431 dbg("%s - slot %s HS_CSR (2) = %04x",
432 __func__, slot_name(slot), hs_csr);
434 if (update_latch_status(slot->hotplug_slot, 1))
435 warn("failure to update latch file");
437 if (update_adapter_status(slot->hotplug_slot, 1))
438 warn("failure to update adapter file");
443 hs_csr = cpci_get_hs_csr(slot);
444 dbg("%s - slot %s HS_CSR (3) = %04x",
445 __func__, slot_name(slot), hs_csr);
448 } else if (cpci_check_ext(slot)) {
449 /* Process extraction request */
450 dbg("%s - slot %s extracted",
451 __func__, slot_name(slot));
454 hs_csr = cpci_get_hs_csr(slot);
455 dbg("%s - slot %s HS_CSR = %04x",
456 __func__, slot_name(slot), hs_csr);
458 if (!slot->extracting) {
459 if (update_latch_status(slot->hotplug_slot, 0))
460 warn("failure to update latch file");
462 slot->extracting = 1;
463 atomic_inc(&extracting);
466 } else if (slot->extracting) {
467 hs_csr = cpci_get_hs_csr(slot);
468 if (hs_csr == 0xffff) {
470 * Hmmm, we're likely hosed at this point, should we
471 * bother trying to tell the driver or not?
473 err("card in slot %s was improperly removed",
475 if (update_adapter_status(slot->hotplug_slot, 0))
476 warn("failure to update adapter file");
477 slot->extracting = 0;
478 atomic_dec(&extracting);
482 up_read(&list_rwsem);
483 dbg("inserted=%d, extracted=%d, extracting=%d",
484 inserted, extracted, atomic_read(&extracting));
485 if (inserted || extracted)
487 else if (!atomic_read(&extracting)) {
488 err("cannot find ENUM# source, shutting down");
494 /* This is the interrupt mode worker thread body */
496 event_thread(void *data)
500 dbg("%s - event thread started", __func__);
502 dbg("event thread sleeping");
503 set_current_state(TASK_INTERRUPTIBLE);
505 if (kthread_should_stop())
510 /* Give userspace a chance to handle extraction */
513 dbg("%s - error checking slots", __func__);
517 } while (atomic_read(&extracting) && !kthread_should_stop());
518 if (kthread_should_stop())
521 /* Re-enable ENUM# interrupt */
522 dbg("%s - re-enabling irq", __func__);
523 controller->ops->enable_irq();
529 /* This is the polling mode worker thread body */
531 poll_thread(void *data)
536 if (kthread_should_stop() || signal_pending(current))
538 if (controller->ops->query_enum()) {
542 /* Give userspace a chance to handle extraction */
545 dbg("%s - error checking slots", __func__);
549 } while (atomic_read(&extracting) && !kthread_should_stop());
558 cpci_start_thread(void)
561 cpci_thread = kthread_run(event_thread, NULL, "cpci_hp_eventd");
563 cpci_thread = kthread_run(poll_thread, NULL, "cpci_hp_polld");
564 if (IS_ERR(cpci_thread)) {
565 err("Can't start up our thread");
566 return PTR_ERR(cpci_thread);
573 cpci_stop_thread(void)
575 kthread_stop(cpci_thread);
580 cpci_hp_register_controller(struct cpci_hp_controller *new_controller)
586 if (!(new_controller && new_controller->ops))
588 if (new_controller->irq) {
589 if (!(new_controller->ops->enable_irq &&
590 new_controller->ops->disable_irq))
592 if (request_irq(new_controller->irq,
594 new_controller->irq_flags,
596 new_controller->dev_id)) {
597 err("Can't get irq %d for the hotplug cPCI controller",
598 new_controller->irq);
601 dbg("%s - acquired controller irq %d",
602 __func__, new_controller->irq);
605 controller = new_controller;
608 EXPORT_SYMBOL_GPL(cpci_hp_register_controller);
617 * Unregister all of our slots with the pci_hotplug subsystem,
618 * and free up all memory that we had allocated.
620 down_write(&list_rwsem);
623 list_for_each_entry_safe(slot, tmp, &slot_list, slot_list) {
624 list_del(&slot->slot_list);
625 pci_hp_deregister(slot->hotplug_slot);
628 up_write(&list_rwsem);
633 cpci_hp_unregister_controller(struct cpci_hp_controller *old_controller)
638 if (!thread_finished)
641 free_irq(controller->irq, controller->dev_id);
648 EXPORT_SYMBOL_GPL(cpci_hp_unregister_controller);
653 static int first = 1;
656 dbg("%s - enter", __func__);
660 down_read(&list_rwsem);
661 if (list_empty(&slot_list)) {
662 up_read(&list_rwsem);
665 up_read(&list_rwsem);
667 status = init_slots(first);
673 status = cpci_start_thread();
676 dbg("%s - thread started", __func__);
678 if (controller->irq) {
679 /* Start enum interrupt processing */
680 dbg("%s - enabling irq", __func__);
681 controller->ops->enable_irq();
683 dbg("%s - exit", __func__);
686 EXPORT_SYMBOL_GPL(cpci_hp_start);
693 if (controller->irq) {
694 /* Stop enum interrupt processing */
695 dbg("%s - disabling irq", __func__);
696 controller->ops->disable_irq();
701 EXPORT_SYMBOL_GPL(cpci_hp_stop);
704 cpci_hotplug_init(int debug)