1 /** @file
2 PCI Hot Plug support functions implementation for PCI Bus module..
3
4 Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
5 SPDX-License-Identifier: BSD-2-Clause-Patent
6
7 **/
8
9 #include "PciBus.h"
10
11 EFI_PCI_HOT_PLUG_INIT_PROTOCOL *gPciHotPlugInit = NULL;
12 EFI_HPC_LOCATION *gPciRootHpcPool = NULL;
13 UINTN gPciRootHpcCount = 0;
14 ROOT_HPC_DATA *gPciRootHpcData = NULL;
15
16
17 /**
18 Event notification function to set Hot Plug controller status.
19
20 @param Event The event that invoke this function.
21 @param Context The calling context, pointer to ROOT_HPC_DATA.
22
23 **/
24 VOID
25 EFIAPI
PciHPCInitialized(IN EFI_EVENT Event,IN VOID * Context)26 PciHPCInitialized (
27 IN EFI_EVENT Event,
28 IN VOID *Context
29 )
30 {
31 ROOT_HPC_DATA *HpcData;
32
33 HpcData = (ROOT_HPC_DATA *) Context;
34 HpcData->Initialized = TRUE;
35 }
36
37 /**
38 Compare two device paths to check if they are exactly same.
39
40 @param DevicePath1 A pointer to the first device path data structure.
41 @param DevicePath2 A pointer to the second device path data structure.
42
43 @retval TRUE They are same.
44 @retval FALSE They are not same.
45
46 **/
47 BOOLEAN
EfiCompareDevicePath(IN EFI_DEVICE_PATH_PROTOCOL * DevicePath1,IN EFI_DEVICE_PATH_PROTOCOL * DevicePath2)48 EfiCompareDevicePath (
49 IN EFI_DEVICE_PATH_PROTOCOL *DevicePath1,
50 IN EFI_DEVICE_PATH_PROTOCOL *DevicePath2
51 )
52 {
53 UINTN Size1;
54 UINTN Size2;
55
56 Size1 = GetDevicePathSize (DevicePath1);
57 Size2 = GetDevicePathSize (DevicePath2);
58
59 if (Size1 != Size2) {
60 return FALSE;
61 }
62
63 if (CompareMem (DevicePath1, DevicePath2, Size1) != 0) {
64 return FALSE;
65 }
66
67 return TRUE;
68 }
69
70 /**
71 Check hot plug support and initialize root hot plug private data.
72
73 If Hot Plug is supported by the platform, call PCI Hot Plug Init protocol
74 to get PCI Hot Plug controller's information and constructor the root hot plug
75 private data structure.
76
77 @retval EFI_SUCCESS They are same.
78 @retval EFI_UNSUPPORTED No PCI Hot Plug controller on the platform.
79 @retval EFI_OUT_OF_RESOURCES No memory to constructor root hot plug private
80 data structure.
81
82 **/
83 EFI_STATUS
InitializeHotPlugSupport(VOID)84 InitializeHotPlugSupport (
85 VOID
86 )
87 {
88 EFI_STATUS Status;
89 EFI_HPC_LOCATION *HpcList;
90 UINTN HpcCount;
91
92 //
93 // Locate the PciHotPlugInit Protocol
94 // If it doesn't exist, that means there is no
95 // hot plug controller supported on the platform
96 // the PCI Bus driver is running on. HotPlug Support
97 // is an optional feature, so absence of the protocol
98 // won't incur the penalty.
99 //
100 Status = gBS->LocateProtocol (
101 &gEfiPciHotPlugInitProtocolGuid,
102 NULL,
103 (VOID **) &gPciHotPlugInit
104 );
105
106 if (EFI_ERROR (Status)) {
107 return EFI_UNSUPPORTED;
108 }
109
110 Status = gPciHotPlugInit->GetRootHpcList (
111 gPciHotPlugInit,
112 &HpcCount,
113 &HpcList
114 );
115
116 if (!EFI_ERROR (Status)) {
117
118 gPciRootHpcPool = HpcList;
119 gPciRootHpcCount = HpcCount;
120 gPciRootHpcData = AllocateZeroPool (sizeof (ROOT_HPC_DATA) * gPciRootHpcCount);
121 if (gPciRootHpcData == NULL) {
122 return EFI_OUT_OF_RESOURCES;
123 }
124 }
125
126 return EFI_SUCCESS;
127 }
128
129 /**
130 Test whether device path is for root pci hot plug bus.
131
132 @param HpbDevicePath A pointer to device path data structure to be tested.
133 @param HpIndex If HpIndex is not NULL, return the index of root hot
134 plug in global array when TRUE is returned.
135
136 @retval TRUE The device path is for root pci hot plug bus.
137 @retval FALSE The device path is not for root pci hot plug bus.
138
139 **/
140 BOOLEAN
IsRootPciHotPlugBus(IN EFI_DEVICE_PATH_PROTOCOL * HpbDevicePath,OUT UINTN * HpIndex OPTIONAL)141 IsRootPciHotPlugBus (
142 IN EFI_DEVICE_PATH_PROTOCOL *HpbDevicePath,
143 OUT UINTN *HpIndex OPTIONAL
144 )
145 {
146 UINTN Index;
147
148 for (Index = 0; Index < gPciRootHpcCount; Index++) {
149
150 if (EfiCompareDevicePath (gPciRootHpcPool[Index].HpbDevicePath, HpbDevicePath)) {
151
152 if (HpIndex != NULL) {
153 *HpIndex = Index;
154 }
155
156 return TRUE;
157 }
158 }
159
160 return FALSE;
161 }
162
163 /**
164 Test whether device path is for root pci hot plug controller.
165
166 @param HpcDevicePath A pointer to device path data structure to be tested.
167 @param HpIndex If HpIndex is not NULL, return the index of root hot
168 plug in global array when TRUE is returned.
169
170 @retval TRUE The device path is for root pci hot plug controller.
171 @retval FALSE The device path is not for root pci hot plug controller.
172
173 **/
174 BOOLEAN
IsRootPciHotPlugController(IN EFI_DEVICE_PATH_PROTOCOL * HpcDevicePath,OUT UINTN * HpIndex)175 IsRootPciHotPlugController (
176 IN EFI_DEVICE_PATH_PROTOCOL *HpcDevicePath,
177 OUT UINTN *HpIndex
178 )
179 {
180 UINTN Index;
181
182 for (Index = 0; Index < gPciRootHpcCount; Index++) {
183
184 if (EfiCompareDevicePath (gPciRootHpcPool[Index].HpcDevicePath, HpcDevicePath)) {
185
186 if (HpIndex != NULL) {
187 *HpIndex = Index;
188 }
189
190 return TRUE;
191 }
192 }
193
194 return FALSE;
195 }
196
197 /**
198 Creating event object for PCI Hot Plug controller.
199
200 @param HpIndex Index of hot plug device in global array.
201 @param Event The returned event that invoke this function.
202
203 @return Status of create event.
204
205 **/
206 EFI_STATUS
CreateEventForHpc(IN UINTN HpIndex,OUT EFI_EVENT * Event)207 CreateEventForHpc (
208 IN UINTN HpIndex,
209 OUT EFI_EVENT *Event
210 )
211 {
212 EFI_STATUS Status;
213
214 Status = gBS->CreateEvent (
215 EVT_NOTIFY_SIGNAL,
216 TPL_CALLBACK,
217 PciHPCInitialized,
218 gPciRootHpcData + HpIndex,
219 &((gPciRootHpcData + HpIndex)->Event)
220 );
221
222 if (!EFI_ERROR (Status)) {
223 *Event = (gPciRootHpcData + HpIndex)->Event;
224 }
225
226 return Status;
227 }
228
229 /**
230 Wait for all root PCI Hot Plug controller finished initializing.
231
232 @param TimeoutInMicroSeconds Microseconds to wait for all root HPCs' initialization.
233
234 @retval EFI_SUCCESS All HPCs initialization finished.
235 @retval EFI_TIMEOUT Not ALL HPCs initialization finished in Microseconds.
236
237 **/
238 EFI_STATUS
AllRootHPCInitialized(IN UINTN TimeoutInMicroSeconds)239 AllRootHPCInitialized (
240 IN UINTN TimeoutInMicroSeconds
241 )
242 {
243 UINT32 Delay;
244 UINTN Index;
245
246 Delay = (UINT32) ((TimeoutInMicroSeconds / 30) + 1);
247
248 do {
249 for (Index = 0; Index < gPciRootHpcCount; Index++) {
250
251 if (gPciRootHpcData[Index].Found && !gPciRootHpcData[Index].Initialized) {
252 break;
253 }
254 }
255
256 if (Index == gPciRootHpcCount) {
257 return EFI_SUCCESS;
258 }
259
260 //
261 // Stall for 30 microseconds..
262 //
263 gBS->Stall (30);
264
265 Delay--;
266
267 } while (Delay > 0);
268
269 return EFI_TIMEOUT;
270 }
271
272 /**
273 Check whether PCI-PCI bridge has PCI Hot Plug capability register block.
274
275 @param PciIoDevice A Pointer to the PCI-PCI bridge.
276
277 @retval TRUE PCI device is HPC.
278 @retval FALSE PCI device is not HPC.
279
280 **/
281 BOOLEAN
IsSHPC(IN PCI_IO_DEVICE * PciIoDevice)282 IsSHPC (
283 IN PCI_IO_DEVICE *PciIoDevice
284 )
285 {
286
287 EFI_STATUS Status;
288 UINT8 Offset;
289
290 if (PciIoDevice == NULL) {
291 return FALSE;
292 }
293
294 Offset = 0;
295 Status = LocateCapabilityRegBlock (
296 PciIoDevice,
297 EFI_PCI_CAPABILITY_ID_SHPC,
298 &Offset,
299 NULL
300 );
301
302 //
303 // If the PCI-PCI bridge has the hot plug controller build-in,
304 // then return TRUE;
305 //
306 if (!EFI_ERROR (Status)) {
307 return TRUE;
308 }
309
310 return FALSE;
311 }
312
313 /**
314 Check whether PciIoDevice supports PCIe hotplug.
315
316 This is equivalent to the following condition:
317 - the device is either a PCIe switch downstream port or a root port,
318 - and the device has the SlotImplemented bit set in its PCIe capability
319 register,
320 - and the device has the HotPlugCapable bit set in its slot capabilities
321 register.
322
323 @param[in] PciIoDevice The device being checked.
324
325 @retval TRUE PciIoDevice is a PCIe port that accepts a hot-plugged device.
326 @retval FALSE Otherwise.
327
328 **/
329 BOOLEAN
SupportsPcieHotplug(IN PCI_IO_DEVICE * PciIoDevice)330 SupportsPcieHotplug (
331 IN PCI_IO_DEVICE *PciIoDevice
332 )
333 {
334 UINT32 Offset;
335 EFI_STATUS Status;
336 PCI_REG_PCIE_CAPABILITY Capability;
337 PCI_REG_PCIE_SLOT_CAPABILITY SlotCapability;
338
339 if (PciIoDevice == NULL) {
340 return FALSE;
341 }
342
343 //
344 // Read the PCI Express Capabilities Register
345 //
346 if (!PciIoDevice->IsPciExp) {
347 return FALSE;
348 }
349 Offset = PciIoDevice->PciExpressCapabilityOffset +
350 OFFSET_OF (PCI_CAPABILITY_PCIEXP, Capability);
351 Status = PciIoDevice->PciIo.Pci.Read (
352 &PciIoDevice->PciIo,
353 EfiPciIoWidthUint16,
354 Offset,
355 1,
356 &Capability
357 );
358 if (EFI_ERROR (Status)) {
359 return FALSE;
360 }
361
362 //
363 // Check the contents of the register
364 //
365 switch (Capability.Bits.DevicePortType) {
366 case PCIE_DEVICE_PORT_TYPE_ROOT_PORT:
367 case PCIE_DEVICE_PORT_TYPE_DOWNSTREAM_PORT:
368 break;
369 default:
370 return FALSE;
371 }
372 if (!Capability.Bits.SlotImplemented) {
373 return FALSE;
374 }
375
376 //
377 // Read the Slot Capabilities Register
378 //
379 Offset = PciIoDevice->PciExpressCapabilityOffset +
380 OFFSET_OF (PCI_CAPABILITY_PCIEXP, SlotCapability);
381 Status = PciIoDevice->PciIo.Pci.Read (
382 &PciIoDevice->PciIo,
383 EfiPciIoWidthUint32,
384 Offset,
385 1,
386 &SlotCapability
387 );
388 if (EFI_ERROR (Status)) {
389 return FALSE;
390 }
391
392 //
393 // Check the contents of the register
394 //
395 if (SlotCapability.Bits.HotPlugCapable) {
396 return TRUE;
397 }
398 return FALSE;
399 }
400
401 /**
402 Get resource padding if the specified PCI bridge is a hot plug bus.
403
404 @param PciIoDevice PCI bridge instance.
405
406 **/
407 VOID
GetResourcePaddingForHpb(IN PCI_IO_DEVICE * PciIoDevice)408 GetResourcePaddingForHpb (
409 IN PCI_IO_DEVICE *PciIoDevice
410 )
411 {
412 EFI_STATUS Status;
413 EFI_HPC_STATE State;
414 UINT64 PciAddress;
415 EFI_HPC_PADDING_ATTRIBUTES Attributes;
416 EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Descriptors;
417
418 if (IsPciHotPlugBus (PciIoDevice)) {
419 //
420 // If PCI-PCI bridge device is PCI Hot Plug bus.
421 //
422 PciAddress = EFI_PCI_ADDRESS (PciIoDevice->BusNumber, PciIoDevice->DeviceNumber, PciIoDevice->FunctionNumber, 0);
423 Status = gPciHotPlugInit->GetResourcePadding (
424 gPciHotPlugInit,
425 PciIoDevice->DevicePath,
426 PciAddress,
427 &State,
428 (VOID **) &Descriptors,
429 &Attributes
430 );
431
432 if (EFI_ERROR (Status)) {
433 return;
434 }
435
436 if ((State & EFI_HPC_STATE_ENABLED) != 0 && (State & EFI_HPC_STATE_INITIALIZED) != 0) {
437 PciIoDevice->ResourcePaddingDescriptors = Descriptors;
438 PciIoDevice->PaddingAttributes = Attributes;
439 }
440
441 return;
442 }
443 }
444
445 /**
446 Test whether PCI device is hot plug bus.
447
448 @param PciIoDevice PCI device instance.
449
450 @retval TRUE PCI device is a hot plug bus.
451 @retval FALSE PCI device is not a hot plug bus.
452
453 **/
454 BOOLEAN
IsPciHotPlugBus(PCI_IO_DEVICE * PciIoDevice)455 IsPciHotPlugBus (
456 PCI_IO_DEVICE *PciIoDevice
457 )
458 {
459 if (IsSHPC (PciIoDevice)) {
460 //
461 // If the PPB has the hot plug controller build-in,
462 // then return TRUE;
463 //
464 return TRUE;
465 }
466
467 if (SupportsPcieHotplug (PciIoDevice)) {
468 //
469 // If the PPB is a PCIe root complex port or a switch downstream port, and
470 // implements a hot-plug capable slot, then also return TRUE.
471 //
472 return TRUE;
473 }
474
475 //
476 // Otherwise, see if it is a Root HPC
477 //
478 if(IsRootPciHotPlugBus (PciIoDevice->DevicePath, NULL)) {
479 return TRUE;
480 }
481
482 return FALSE;
483 }
484
485