1 /*
2 * File: portdrv_core.c
3 * Purpose: PCI Express Port Bus Driver's Core Functions
4 *
5 * Copyright (C) 2004 Intel
6 * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com)
7 */
8
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/kernel.h>
12 #include <linux/errno.h>
13 #include <linux/pm.h>
14 #include <linux/string.h>
15 #include <linux/slab.h>
16 #include <linux/pcieport_if.h>
17
18 #include "portdrv.h"
19
20 extern int pcie_mch_quirk; /* MSI-quirk Indicator */
21
22 /**
23 * release_pcie_device - free PCI Express port service device structure
24 * @dev: Port service device to release
25 *
26 * Invoked automatically when device is being removed in response to
27 * device_unregister(dev). Release all resources being claimed.
28 */
release_pcie_device(struct device * dev)29 static void release_pcie_device(struct device *dev)
30 {
31 kfree(to_pcie_device(dev));
32 }
33
is_msi_quirked(struct pci_dev * dev)34 static int is_msi_quirked(struct pci_dev *dev)
35 {
36 int port_type, quirk = 0;
37 u16 reg16;
38
39 pci_read_config_word(dev,
40 pci_find_capability(dev, PCI_CAP_ID_EXP) +
41 PCIE_CAPABILITIES_REG, ®16);
42 port_type = (reg16 >> 4) & PORT_TYPE_MASK;
43 switch(port_type) {
44 case PCIE_RC_PORT:
45 if (pcie_mch_quirk == 1)
46 quirk = 1;
47 break;
48 case PCIE_SW_UPSTREAM_PORT:
49 case PCIE_SW_DOWNSTREAM_PORT:
50 default:
51 break;
52 }
53 return quirk;
54 }
55
56 /**
57 * assign_interrupt_mode - choose interrupt mode for PCI Express port services
58 * (INTx, MSI-X, MSI) and set up vectors
59 * @dev: PCI Express port to handle
60 * @vectors: Array of interrupt vectors to populate
61 * @mask: Bitmask of port capabilities returned by get_port_device_capability()
62 *
63 * Return value: Interrupt mode associated with the port
64 */
assign_interrupt_mode(struct pci_dev * dev,int * vectors,int mask)65 static int assign_interrupt_mode(struct pci_dev *dev, int *vectors, int mask)
66 {
67 int i, pos, nvec, status = -EINVAL;
68 int interrupt_mode = PCIE_PORT_INTx_MODE;
69
70 /* Set INTx as default */
71 for (i = 0, nvec = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
72 if (mask & (1 << i))
73 nvec++;
74 vectors[i] = dev->irq;
75 }
76
77 /* Check MSI quirk */
78 if (is_msi_quirked(dev))
79 return interrupt_mode;
80
81 /* Select MSI-X over MSI if supported */
82 pos = pci_find_capability(dev, PCI_CAP_ID_MSIX);
83 if (pos) {
84 struct msix_entry msix_entries[PCIE_PORT_DEVICE_MAXSERVICES] =
85 {{0, 0}, {0, 1}, {0, 2}, {0, 3}};
86 status = pci_enable_msix(dev, msix_entries, nvec);
87 if (!status) {
88 int j = 0;
89
90 interrupt_mode = PCIE_PORT_MSIX_MODE;
91 for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
92 if (mask & (1 << i))
93 vectors[i] = msix_entries[j++].vector;
94 }
95 }
96 }
97 if (status) {
98 pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
99 if (pos) {
100 status = pci_enable_msi(dev);
101 if (!status) {
102 interrupt_mode = PCIE_PORT_MSI_MODE;
103 for (i = 0;i < PCIE_PORT_DEVICE_MAXSERVICES;i++)
104 vectors[i] = dev->irq;
105 }
106 }
107 }
108 return interrupt_mode;
109 }
110
111 /**
112 * get_port_device_capability - discover capabilities of a PCI Express port
113 * @dev: PCI Express port to examine
114 *
115 * The capabilities are read from the port's PCI Express configuration registers
116 * as described in PCI Express Base Specification 1.0a sections 7.8.2, 7.8.9 and
117 * 7.9 - 7.11.
118 *
119 * Return value: Bitmask of discovered port capabilities
120 */
get_port_device_capability(struct pci_dev * dev)121 static int get_port_device_capability(struct pci_dev *dev)
122 {
123 int services = 0, pos;
124 u16 reg16;
125 u32 reg32;
126
127 pos = pci_find_capability(dev, PCI_CAP_ID_EXP);
128 pci_read_config_word(dev, pos + PCIE_CAPABILITIES_REG, ®16);
129 /* Hot-Plug Capable */
130 if (reg16 & PORT_TO_SLOT_MASK) {
131 pci_read_config_dword(dev,
132 pos + PCIE_SLOT_CAPABILITIES_REG, ®32);
133 if (reg32 & SLOT_HP_CAPABLE_MASK)
134 services |= PCIE_PORT_SERVICE_HP;
135 }
136 /* PME Capable - root port capability */
137 if (((reg16 >> 4) & PORT_TYPE_MASK) == PCIE_RC_PORT)
138 services |= PCIE_PORT_SERVICE_PME;
139
140 if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR))
141 services |= PCIE_PORT_SERVICE_AER;
142 if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_VC))
143 services |= PCIE_PORT_SERVICE_VC;
144
145 return services;
146 }
147
148 /**
149 * pcie_device_init - initialize PCI Express port service device
150 * @dev: Port service device to initialize
151 * @parent: PCI Express port to associate the service device with
152 * @port_type: Type of the port
153 * @service_type: Type of service to associate with the service device
154 * @irq: Interrupt vector to associate with the service device
155 * @irq_mode: Interrupt mode of the service (INTx, MSI-X, MSI)
156 */
pcie_device_init(struct pci_dev * parent,struct pcie_device * dev,int port_type,int service_type,int irq,int irq_mode)157 static void pcie_device_init(struct pci_dev *parent, struct pcie_device *dev,
158 int port_type, int service_type, int irq, int irq_mode)
159 {
160 struct device *device;
161
162 dev->port = parent;
163 dev->interrupt_mode = irq_mode;
164 dev->irq = irq;
165 dev->id.vendor = parent->vendor;
166 dev->id.device = parent->device;
167 dev->id.port_type = port_type;
168 dev->id.service_type = (1 << service_type);
169
170 /* Initialize generic device interface */
171 device = &dev->device;
172 memset(device, 0, sizeof(struct device));
173 device->bus = &pcie_port_bus_type;
174 device->driver = NULL;
175 device->driver_data = NULL;
176 device->release = release_pcie_device; /* callback to free pcie dev */
177 dev_set_name(device, "%s:pcie%02x",
178 pci_name(parent), get_descriptor_id(port_type, service_type));
179 device->parent = &parent->dev;
180 }
181
182 /**
183 * alloc_pcie_device - allocate PCI Express port service device structure
184 * @parent: PCI Express port to associate the service device with
185 * @port_type: Type of the port
186 * @service_type: Type of service to associate with the service device
187 * @irq: Interrupt vector to associate with the service device
188 * @irq_mode: Interrupt mode of the service (INTx, MSI-X, MSI)
189 */
alloc_pcie_device(struct pci_dev * parent,int port_type,int service_type,int irq,int irq_mode)190 static struct pcie_device* alloc_pcie_device(struct pci_dev *parent,
191 int port_type, int service_type, int irq, int irq_mode)
192 {
193 struct pcie_device *device;
194
195 device = kzalloc(sizeof(struct pcie_device), GFP_KERNEL);
196 if (!device)
197 return NULL;
198
199 pcie_device_init(parent, device, port_type, service_type, irq,irq_mode);
200 return device;
201 }
202
203 /**
204 * pcie_port_device_probe - check if device is a PCI Express port
205 * @dev: Device to check
206 */
pcie_port_device_probe(struct pci_dev * dev)207 int pcie_port_device_probe(struct pci_dev *dev)
208 {
209 int pos, type;
210 u16 reg;
211
212 if (!(pos = pci_find_capability(dev, PCI_CAP_ID_EXP)))
213 return -ENODEV;
214
215 pci_read_config_word(dev, pos + PCIE_CAPABILITIES_REG, ®);
216 type = (reg >> 4) & PORT_TYPE_MASK;
217 if ( type == PCIE_RC_PORT || type == PCIE_SW_UPSTREAM_PORT ||
218 type == PCIE_SW_DOWNSTREAM_PORT )
219 return 0;
220
221 return -ENODEV;
222 }
223
224 /**
225 * pcie_port_device_register - register PCI Express port
226 * @dev: PCI Express port to register
227 *
228 * Allocate the port extension structure and register services associated with
229 * the port.
230 */
pcie_port_device_register(struct pci_dev * dev)231 int pcie_port_device_register(struct pci_dev *dev)
232 {
233 struct pcie_port_device_ext *p_ext;
234 int status, type, capabilities, irq_mode, i;
235 int vectors[PCIE_PORT_DEVICE_MAXSERVICES];
236 u16 reg16;
237
238 /* Allocate port device extension */
239 if (!(p_ext = kmalloc(sizeof(struct pcie_port_device_ext), GFP_KERNEL)))
240 return -ENOMEM;
241
242 pci_set_drvdata(dev, p_ext);
243
244 /* Get port type */
245 pci_read_config_word(dev,
246 pci_find_capability(dev, PCI_CAP_ID_EXP) +
247 PCIE_CAPABILITIES_REG, ®16);
248 type = (reg16 >> 4) & PORT_TYPE_MASK;
249
250 /* Now get port services */
251 capabilities = get_port_device_capability(dev);
252 irq_mode = assign_interrupt_mode(dev, vectors, capabilities);
253 p_ext->interrupt_mode = irq_mode;
254
255 /* Allocate child services if any */
256 for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) {
257 struct pcie_device *child;
258
259 if (capabilities & (1 << i)) {
260 child = alloc_pcie_device(
261 dev, /* parent */
262 type, /* port type */
263 i, /* service type */
264 vectors[i], /* irq */
265 irq_mode /* interrupt mode */);
266 if (child) {
267 status = device_register(&child->device);
268 if (status) {
269 kfree(child);
270 continue;
271 }
272 get_device(&child->device);
273 }
274 }
275 }
276 return 0;
277 }
278
279 #ifdef CONFIG_PM
suspend_iter(struct device * dev,void * data)280 static int suspend_iter(struct device *dev, void *data)
281 {
282 struct pcie_port_service_driver *service_driver;
283 pm_message_t state = * (pm_message_t *) data;
284
285 if ((dev->bus == &pcie_port_bus_type) &&
286 (dev->driver)) {
287 service_driver = to_service_driver(dev->driver);
288 if (service_driver->suspend)
289 service_driver->suspend(to_pcie_device(dev), state);
290 }
291 return 0;
292 }
293
294 /**
295 * pcie_port_device_suspend - suspend port services associated with a PCIe port
296 * @dev: PCI Express port to handle
297 * @state: Representation of system power management transition in progress
298 */
pcie_port_device_suspend(struct pci_dev * dev,pm_message_t state)299 int pcie_port_device_suspend(struct pci_dev *dev, pm_message_t state)
300 {
301 return device_for_each_child(&dev->dev, &state, suspend_iter);
302 }
303
resume_iter(struct device * dev,void * data)304 static int resume_iter(struct device *dev, void *data)
305 {
306 struct pcie_port_service_driver *service_driver;
307
308 if ((dev->bus == &pcie_port_bus_type) &&
309 (dev->driver)) {
310 service_driver = to_service_driver(dev->driver);
311 if (service_driver->resume)
312 service_driver->resume(to_pcie_device(dev));
313 }
314 return 0;
315 }
316
317 /**
318 * pcie_port_device_suspend - resume port services associated with a PCIe port
319 * @dev: PCI Express port to handle
320 */
pcie_port_device_resume(struct pci_dev * dev)321 int pcie_port_device_resume(struct pci_dev *dev)
322 {
323 return device_for_each_child(&dev->dev, NULL, resume_iter);
324 }
325 #endif
326
remove_iter(struct device * dev,void * data)327 static int remove_iter(struct device *dev, void *data)
328 {
329 struct pcie_port_service_driver *service_driver;
330
331 if (dev->bus == &pcie_port_bus_type) {
332 if (dev->driver) {
333 service_driver = to_service_driver(dev->driver);
334 if (service_driver->remove)
335 service_driver->remove(to_pcie_device(dev));
336 }
337 *(unsigned long*)data = (unsigned long)dev;
338 return 1;
339 }
340 return 0;
341 }
342
343 /**
344 * pcie_port_device_remove - unregister PCI Express port service devices
345 * @dev: PCI Express port the service devices to unregister are associated with
346 *
347 * Remove PCI Express port service devices associated with given port and
348 * disable MSI-X or MSI for the port.
349 */
pcie_port_device_remove(struct pci_dev * dev)350 void pcie_port_device_remove(struct pci_dev *dev)
351 {
352 struct device *device;
353 unsigned long device_addr;
354 int interrupt_mode = PCIE_PORT_INTx_MODE;
355 int status;
356
357 do {
358 status = device_for_each_child(&dev->dev, &device_addr, remove_iter);
359 if (status) {
360 device = (struct device*)device_addr;
361 interrupt_mode = (to_pcie_device(device))->interrupt_mode;
362 put_device(device);
363 device_unregister(device);
364 }
365 } while (status);
366 /* Switch to INTx by default if MSI enabled */
367 if (interrupt_mode == PCIE_PORT_MSIX_MODE)
368 pci_disable_msix(dev);
369 else if (interrupt_mode == PCIE_PORT_MSI_MODE)
370 pci_disable_msi(dev);
371 }
372
373 /**
374 * pcie_port_probe_service - probe driver for given PCI Express port service
375 * @dev: PCI Express port service device to probe against
376 *
377 * If PCI Express port service driver is registered with
378 * pcie_port_service_register(), this function will be called by the driver core
379 * whenever match is found between the driver and a port service device.
380 */
pcie_port_probe_service(struct device * dev)381 static int pcie_port_probe_service(struct device *dev)
382 {
383 struct pcie_device *pciedev;
384 struct pcie_port_service_driver *driver;
385 int status;
386
387 if (!dev || !dev->driver)
388 return -ENODEV;
389
390 driver = to_service_driver(dev->driver);
391 if (!driver || !driver->probe)
392 return -ENODEV;
393
394 pciedev = to_pcie_device(dev);
395 status = driver->probe(pciedev, driver->id_table);
396 if (!status) {
397 dev_printk(KERN_DEBUG, dev, "service driver %s loaded\n",
398 driver->name);
399 get_device(dev);
400 }
401 return status;
402 }
403
404 /**
405 * pcie_port_remove_service - detach driver from given PCI Express port service
406 * @dev: PCI Express port service device to handle
407 *
408 * If PCI Express port service driver is registered with
409 * pcie_port_service_register(), this function will be called by the driver core
410 * when device_unregister() is called for the port service device associated
411 * with the driver.
412 */
pcie_port_remove_service(struct device * dev)413 static int pcie_port_remove_service(struct device *dev)
414 {
415 struct pcie_device *pciedev;
416 struct pcie_port_service_driver *driver;
417
418 if (!dev || !dev->driver)
419 return 0;
420
421 pciedev = to_pcie_device(dev);
422 driver = to_service_driver(dev->driver);
423 if (driver && driver->remove) {
424 dev_printk(KERN_DEBUG, dev, "unloading service driver %s\n",
425 driver->name);
426 driver->remove(pciedev);
427 put_device(dev);
428 }
429 return 0;
430 }
431
432 /**
433 * pcie_port_shutdown_service - shut down given PCI Express port service
434 * @dev: PCI Express port service device to handle
435 *
436 * If PCI Express port service driver is registered with
437 * pcie_port_service_register(), this function will be called by the driver core
438 * when device_shutdown() is called for the port service device associated
439 * with the driver.
440 */
pcie_port_shutdown_service(struct device * dev)441 static void pcie_port_shutdown_service(struct device *dev) {}
442
443 /**
444 * pcie_port_service_register - register PCI Express port service driver
445 * @new: PCI Express port service driver to register
446 */
pcie_port_service_register(struct pcie_port_service_driver * new)447 int pcie_port_service_register(struct pcie_port_service_driver *new)
448 {
449 new->driver.name = (char *)new->name;
450 new->driver.bus = &pcie_port_bus_type;
451 new->driver.probe = pcie_port_probe_service;
452 new->driver.remove = pcie_port_remove_service;
453 new->driver.shutdown = pcie_port_shutdown_service;
454
455 return driver_register(&new->driver);
456 }
457
458 /**
459 * pcie_port_service_unregister - unregister PCI Express port service driver
460 * @drv: PCI Express port service driver to unregister
461 */
pcie_port_service_unregister(struct pcie_port_service_driver * drv)462 void pcie_port_service_unregister(struct pcie_port_service_driver *drv)
463 {
464 driver_unregister(&drv->driver);
465 }
466
467 EXPORT_SYMBOL(pcie_port_service_register);
468 EXPORT_SYMBOL(pcie_port_service_unregister);
469