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13#include <linux/module.h>
14#include <linux/pci.h>
15#include <linux/kernel.h>
16#include <linux/errno.h>
17#include <linux/slab.h>
18#include <linux/init.h>
19#include <linux/interrupt.h>
20#include <linux/device.h>
21#include <linux/pcieport_if.h>
22#include <linux/acpi.h>
23#include <linux/pci-acpi.h>
24#include <linux/pm_runtime.h>
25
26#include "../pci.h"
27#include "portdrv.h"
28
29
30
31
32
33
34
35bool pcie_pme_msi_disabled;
36
37static int __init pcie_pme_setup(char *str)
38{
39 if (!strncmp(str, "nomsi", 5))
40 pcie_pme_msi_disabled = true;
41
42 return 1;
43}
44__setup("pcie_pme=", pcie_pme_setup);
45
46struct pcie_pme_service_data {
47 spinlock_t lock;
48 struct pcie_device *srv;
49 struct work_struct work;
50 bool noirq;
51};
52
53
54
55
56
57
58void pcie_pme_interrupt_enable(struct pci_dev *dev, bool enable)
59{
60 if (enable)
61 pcie_capability_set_word(dev, PCI_EXP_RTCTL,
62 PCI_EXP_RTCTL_PMEIE);
63 else
64 pcie_capability_clear_word(dev, PCI_EXP_RTCTL,
65 PCI_EXP_RTCTL_PMEIE);
66}
67
68
69
70
71
72
73
74static bool pcie_pme_walk_bus(struct pci_bus *bus)
75{
76 struct pci_dev *dev;
77 bool ret = false;
78
79 list_for_each_entry(dev, &bus->devices, bus_list) {
80
81 if (!pci_is_pcie(dev) && pci_check_pme_status(dev)) {
82 if (dev->pme_poll)
83 dev->pme_poll = false;
84
85 pci_wakeup_event(dev);
86 pm_request_resume(&dev->dev);
87 ret = true;
88 }
89
90 if (dev->subordinate && pcie_pme_walk_bus(dev->subordinate))
91 ret = true;
92 }
93
94 return ret;
95}
96
97
98
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100
101
102
103
104
105
106static bool pcie_pme_from_pci_bridge(struct pci_bus *bus, u8 devfn)
107{
108 struct pci_dev *dev;
109 bool found = false;
110
111 if (devfn)
112 return false;
113
114 dev = pci_dev_get(bus->self);
115 if (!dev)
116 return false;
117
118 if (pci_is_pcie(dev) && pci_pcie_type(dev) == PCI_EXP_TYPE_PCI_BRIDGE) {
119 down_read(&pci_bus_sem);
120 if (pcie_pme_walk_bus(bus))
121 found = true;
122 up_read(&pci_bus_sem);
123 }
124
125 pci_dev_put(dev);
126 return found;
127}
128
129
130
131
132
133
134static void pcie_pme_handle_request(struct pci_dev *port, u16 req_id)
135{
136 u8 busnr = req_id >> 8, devfn = req_id & 0xff;
137 struct pci_bus *bus;
138 struct pci_dev *dev;
139 bool found = false;
140
141
142 if (port->devfn == devfn && port->bus->number == busnr) {
143 if (port->pme_poll)
144 port->pme_poll = false;
145
146 if (pci_check_pme_status(port)) {
147 pm_request_resume(&port->dev);
148 found = true;
149 } else {
150
151
152
153
154
155
156
157
158 down_read(&pci_bus_sem);
159 found = pcie_pme_walk_bus(port->subordinate);
160 up_read(&pci_bus_sem);
161 }
162 goto out;
163 }
164
165
166 bus = pci_find_bus(pci_domain_nr(port->bus), busnr);
167 if (!bus)
168 goto out;
169
170
171 found = pcie_pme_from_pci_bridge(bus, devfn);
172 if (found)
173 goto out;
174
175
176 down_read(&pci_bus_sem);
177 list_for_each_entry(dev, &bus->devices, bus_list) {
178 pci_dev_get(dev);
179 if (dev->devfn == devfn) {
180 found = true;
181 break;
182 }
183 pci_dev_put(dev);
184 }
185 up_read(&pci_bus_sem);
186
187 if (found) {
188
189 found = pci_check_pme_status(dev);
190 if (found) {
191 if (dev->pme_poll)
192 dev->pme_poll = false;
193
194 pci_wakeup_event(dev);
195 pm_request_resume(&dev->dev);
196 }
197 pci_dev_put(dev);
198 } else if (devfn) {
199
200
201
202
203
204 dev_dbg(&port->dev, "PME interrupt generated for "
205 "non-existent device %02x:%02x.%d\n",
206 busnr, PCI_SLOT(devfn), PCI_FUNC(devfn));
207 found = pcie_pme_from_pci_bridge(bus, 0);
208 }
209
210 out:
211 if (!found)
212 dev_dbg(&port->dev, "Spurious native PME interrupt!\n");
213}
214
215
216
217
218
219static void pcie_pme_work_fn(struct work_struct *work)
220{
221 struct pcie_pme_service_data *data =
222 container_of(work, struct pcie_pme_service_data, work);
223 struct pci_dev *port = data->srv->port;
224 u32 rtsta;
225
226 spin_lock_irq(&data->lock);
227
228 for (;;) {
229 if (data->noirq)
230 break;
231
232 pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta);
233 if (rtsta & PCI_EXP_RTSTA_PME) {
234
235
236
237
238 pcie_clear_root_pme_status(port);
239
240 spin_unlock_irq(&data->lock);
241 pcie_pme_handle_request(port, rtsta & 0xffff);
242 spin_lock_irq(&data->lock);
243
244 continue;
245 }
246
247
248 if (!(rtsta & PCI_EXP_RTSTA_PENDING))
249 break;
250
251 spin_unlock_irq(&data->lock);
252 cpu_relax();
253 spin_lock_irq(&data->lock);
254 }
255
256 if (!data->noirq)
257 pcie_pme_interrupt_enable(port, true);
258
259 spin_unlock_irq(&data->lock);
260}
261
262
263
264
265
266
267static irqreturn_t pcie_pme_irq(int irq, void *context)
268{
269 struct pci_dev *port;
270 struct pcie_pme_service_data *data;
271 u32 rtsta;
272 unsigned long flags;
273
274 port = ((struct pcie_device *)context)->port;
275 data = get_service_data((struct pcie_device *)context);
276
277 spin_lock_irqsave(&data->lock, flags);
278 pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta);
279
280 if (!(rtsta & PCI_EXP_RTSTA_PME)) {
281 spin_unlock_irqrestore(&data->lock, flags);
282 return IRQ_NONE;
283 }
284
285 pcie_pme_interrupt_enable(port, false);
286 spin_unlock_irqrestore(&data->lock, flags);
287
288
289 schedule_work(&data->work);
290
291 return IRQ_HANDLED;
292}
293
294
295
296
297
298
299static int pcie_pme_set_native(struct pci_dev *dev, void *ign)
300{
301 dev_info(&dev->dev, "Signaling PME through PCIe PME interrupt\n");
302
303 device_set_run_wake(&dev->dev, true);
304 dev->pme_interrupt = true;
305 return 0;
306}
307
308
309
310
311
312
313
314
315
316
317static void pcie_pme_mark_devices(struct pci_dev *port)
318{
319 pcie_pme_set_native(port, NULL);
320 if (port->subordinate) {
321 pci_walk_bus(port->subordinate, pcie_pme_set_native, NULL);
322 } else {
323 struct pci_bus *bus = port->bus;
324 struct pci_dev *dev;
325
326
327 if (pci_pcie_type(port) != PCI_EXP_TYPE_RC_EC || !bus)
328 return;
329
330 down_read(&pci_bus_sem);
331 list_for_each_entry(dev, &bus->devices, bus_list)
332 if (pci_is_pcie(dev)
333 && pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END)
334 pcie_pme_set_native(dev, NULL);
335 up_read(&pci_bus_sem);
336 }
337}
338
339
340
341
342
343static int pcie_pme_probe(struct pcie_device *srv)
344{
345 struct pci_dev *port;
346 struct pcie_pme_service_data *data;
347 int ret;
348
349 data = kzalloc(sizeof(*data), GFP_KERNEL);
350 if (!data)
351 return -ENOMEM;
352
353 spin_lock_init(&data->lock);
354 INIT_WORK(&data->work, pcie_pme_work_fn);
355 data->srv = srv;
356 set_service_data(srv, data);
357
358 port = srv->port;
359 pcie_pme_interrupt_enable(port, false);
360 pcie_clear_root_pme_status(port);
361
362 ret = request_irq(srv->irq, pcie_pme_irq, IRQF_SHARED, "PCIe PME", srv);
363 if (ret) {
364 kfree(data);
365 } else {
366 pcie_pme_mark_devices(port);
367 pcie_pme_interrupt_enable(port, true);
368 }
369
370 return ret;
371}
372
373
374
375
376
377static int pcie_pme_suspend(struct pcie_device *srv)
378{
379 struct pcie_pme_service_data *data = get_service_data(srv);
380 struct pci_dev *port = srv->port;
381
382 spin_lock_irq(&data->lock);
383 pcie_pme_interrupt_enable(port, false);
384 pcie_clear_root_pme_status(port);
385 data->noirq = true;
386 spin_unlock_irq(&data->lock);
387
388 synchronize_irq(srv->irq);
389
390 return 0;
391}
392
393
394
395
396
397static int pcie_pme_resume(struct pcie_device *srv)
398{
399 struct pcie_pme_service_data *data = get_service_data(srv);
400 struct pci_dev *port = srv->port;
401
402 spin_lock_irq(&data->lock);
403 data->noirq = false;
404 pcie_clear_root_pme_status(port);
405 pcie_pme_interrupt_enable(port, true);
406 spin_unlock_irq(&data->lock);
407
408 return 0;
409}
410
411
412
413
414
415static void pcie_pme_remove(struct pcie_device *srv)
416{
417 pcie_pme_suspend(srv);
418 free_irq(srv->irq, srv);
419 kfree(get_service_data(srv));
420}
421
422static struct pcie_port_service_driver pcie_pme_driver = {
423 .name = "pcie_pme",
424 .port_type = PCI_EXP_TYPE_ROOT_PORT,
425 .service = PCIE_PORT_SERVICE_PME,
426
427 .probe = pcie_pme_probe,
428 .suspend = pcie_pme_suspend,
429 .resume = pcie_pme_resume,
430 .remove = pcie_pme_remove,
431};
432
433
434
435
436static int __init pcie_pme_service_init(void)
437{
438 return pcie_port_service_register(&pcie_pme_driver);
439}
440
441module_init(pcie_pme_service_init);
442