1 /*******************************************************************************
2 *
3 * Module Name: hwpci - Obtain PCI bus, device, and function numbers
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2022, Intel Corp.
9 * All rights reserved.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions, and the following disclaimer,
16 * without modification.
17 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18 * substantially similar to the "NO WARRANTY" disclaimer below
19 * ("Disclaimer") and any redistribution must be conditioned upon
20 * including a substantially similar Disclaimer requirement for further
21 * binary redistribution.
22 * 3. Neither the names of the above-listed copyright holders nor the names
23 * of any contributors may be used to endorse or promote products derived
24 * from this software without specific prior written permission.
25 *
26 * Alternatively, this software may be distributed under the terms of the
27 * GNU General Public License ("GPL") version 2 as published by the Free
28 * Software Foundation.
29 *
30 * NO WARRANTY
31 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
34 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41 * POSSIBILITY OF SUCH DAMAGES.
42 */
43
44 #include "acpi.h"
45 #include "accommon.h"
46
47
48 #define _COMPONENT ACPI_NAMESPACE
49 ACPI_MODULE_NAME ("hwpci")
50
51
52 /* PCI configuration space values */
53
54 #define PCI_CFG_HEADER_TYPE_REG 0x0E
55 #define PCI_CFG_PRIMARY_BUS_NUMBER_REG 0x18
56 #define PCI_CFG_SECONDARY_BUS_NUMBER_REG 0x19
57
58 /* PCI header values */
59
60 #define PCI_HEADER_TYPE_MASK 0x7F
61 #define PCI_TYPE_BRIDGE 0x01
62 #define PCI_TYPE_CARDBUS_BRIDGE 0x02
63
64 typedef struct acpi_pci_device
65 {
66 ACPI_HANDLE Device;
67 struct acpi_pci_device *Next;
68
69 } ACPI_PCI_DEVICE;
70
71
72 /* Local prototypes */
73
74 static ACPI_STATUS
75 AcpiHwBuildPciList (
76 ACPI_HANDLE RootPciDevice,
77 ACPI_HANDLE PciRegion,
78 ACPI_PCI_DEVICE **ReturnListHead);
79
80 static ACPI_STATUS
81 AcpiHwProcessPciList (
82 ACPI_PCI_ID *PciId,
83 ACPI_PCI_DEVICE *ListHead);
84
85 static void
86 AcpiHwDeletePciList (
87 ACPI_PCI_DEVICE *ListHead);
88
89 static ACPI_STATUS
90 AcpiHwGetPciDeviceInfo (
91 ACPI_PCI_ID *PciId,
92 ACPI_HANDLE PciDevice,
93 UINT16 *BusNumber,
94 BOOLEAN *IsBridge);
95
96
97 /*******************************************************************************
98 *
99 * FUNCTION: AcpiHwDerivePciId
100 *
101 * PARAMETERS: PciId - Initial values for the PCI ID. May be
102 * modified by this function.
103 * RootPciDevice - A handle to a PCI device object. This
104 * object must be a PCI Root Bridge having a
105 * _HID value of either PNP0A03 or PNP0A08
106 * PciRegion - A handle to a PCI configuration space
107 * Operation Region being initialized
108 *
109 * RETURN: Status
110 *
111 * DESCRIPTION: This function derives a full PCI ID for a PCI device,
112 * consisting of a Segment number, Bus number, Device number,
113 * and function code.
114 *
115 * The PCI hardware dynamically configures PCI bus numbers
116 * depending on the bus topology discovered during system
117 * initialization. This function is invoked during configuration
118 * of a PCI_Config Operation Region in order to (possibly) update
119 * the Bus/Device/Function numbers in the PciId with the actual
120 * values as determined by the hardware and operating system
121 * configuration.
122 *
123 * The PciId parameter is initially populated during the Operation
124 * Region initialization. This function is then called, and is
125 * will make any necessary modifications to the Bus, Device, or
126 * Function number PCI ID subfields as appropriate for the
127 * current hardware and OS configuration.
128 *
129 * NOTE: Created 08/2010. Replaces the previous OSL AcpiOsDerivePciId
130 * interface since this feature is OS-independent. This module
131 * specifically avoids any use of recursion by building a local
132 * temporary device list.
133 *
134 ******************************************************************************/
135
136 ACPI_STATUS
AcpiHwDerivePciId(ACPI_PCI_ID * PciId,ACPI_HANDLE RootPciDevice,ACPI_HANDLE PciRegion)137 AcpiHwDerivePciId (
138 ACPI_PCI_ID *PciId,
139 ACPI_HANDLE RootPciDevice,
140 ACPI_HANDLE PciRegion)
141 {
142 ACPI_STATUS Status;
143 ACPI_PCI_DEVICE *ListHead;
144
145
146 ACPI_FUNCTION_TRACE (HwDerivePciId);
147
148
149 if (!PciId)
150 {
151 return_ACPI_STATUS (AE_BAD_PARAMETER);
152 }
153
154 /* Build a list of PCI devices, from PciRegion up to RootPciDevice */
155
156 Status = AcpiHwBuildPciList (RootPciDevice, PciRegion, &ListHead);
157 if (ACPI_SUCCESS (Status))
158 {
159 /* Walk the list, updating the PCI device/function/bus numbers */
160
161 Status = AcpiHwProcessPciList (PciId, ListHead);
162
163 /* Delete the list */
164
165 AcpiHwDeletePciList (ListHead);
166 }
167
168 return_ACPI_STATUS (Status);
169 }
170
171
172 /*******************************************************************************
173 *
174 * FUNCTION: AcpiHwBuildPciList
175 *
176 * PARAMETERS: RootPciDevice - A handle to a PCI device object. This
177 * object is guaranteed to be a PCI Root
178 * Bridge having a _HID value of either
179 * PNP0A03 or PNP0A08
180 * PciRegion - A handle to the PCI configuration space
181 * Operation Region
182 * ReturnListHead - Where the PCI device list is returned
183 *
184 * RETURN: Status
185 *
186 * DESCRIPTION: Builds a list of devices from the input PCI region up to the
187 * Root PCI device for this namespace subtree.
188 *
189 ******************************************************************************/
190
191 static ACPI_STATUS
AcpiHwBuildPciList(ACPI_HANDLE RootPciDevice,ACPI_HANDLE PciRegion,ACPI_PCI_DEVICE ** ReturnListHead)192 AcpiHwBuildPciList (
193 ACPI_HANDLE RootPciDevice,
194 ACPI_HANDLE PciRegion,
195 ACPI_PCI_DEVICE **ReturnListHead)
196 {
197 ACPI_HANDLE CurrentDevice;
198 ACPI_HANDLE ParentDevice;
199 ACPI_STATUS Status;
200 ACPI_PCI_DEVICE *ListElement;
201
202
203 /*
204 * Ascend namespace branch until the RootPciDevice is reached, building
205 * a list of device nodes. Loop will exit when either the PCI device is
206 * found, or the root of the namespace is reached.
207 */
208 *ReturnListHead = NULL;
209 CurrentDevice = PciRegion;
210 while (1)
211 {
212 Status = AcpiGetParent (CurrentDevice, &ParentDevice);
213 if (ACPI_FAILURE (Status))
214 {
215 /* Must delete the list before exit */
216
217 AcpiHwDeletePciList (*ReturnListHead);
218 return (Status);
219 }
220
221 /* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */
222
223 if (ParentDevice == RootPciDevice)
224 {
225 return (AE_OK);
226 }
227
228 ListElement = ACPI_ALLOCATE (sizeof (ACPI_PCI_DEVICE));
229 if (!ListElement)
230 {
231 /* Must delete the list before exit */
232
233 AcpiHwDeletePciList (*ReturnListHead);
234 return (AE_NO_MEMORY);
235 }
236
237 /* Put new element at the head of the list */
238
239 ListElement->Next = *ReturnListHead;
240 ListElement->Device = ParentDevice;
241 *ReturnListHead = ListElement;
242
243 CurrentDevice = ParentDevice;
244 }
245 }
246
247
248 /*******************************************************************************
249 *
250 * FUNCTION: AcpiHwProcessPciList
251 *
252 * PARAMETERS: PciId - Initial values for the PCI ID. May be
253 * modified by this function.
254 * ListHead - Device list created by
255 * AcpiHwBuildPciList
256 *
257 * RETURN: Status
258 *
259 * DESCRIPTION: Walk downward through the PCI device list, getting the device
260 * info for each, via the PCI configuration space and updating
261 * the PCI ID as necessary. Deletes the list during traversal.
262 *
263 ******************************************************************************/
264
265 static ACPI_STATUS
AcpiHwProcessPciList(ACPI_PCI_ID * PciId,ACPI_PCI_DEVICE * ListHead)266 AcpiHwProcessPciList (
267 ACPI_PCI_ID *PciId,
268 ACPI_PCI_DEVICE *ListHead)
269 {
270 ACPI_STATUS Status = AE_OK;
271 ACPI_PCI_DEVICE *Info;
272 UINT16 BusNumber;
273 BOOLEAN IsBridge = TRUE;
274
275
276 ACPI_FUNCTION_NAME (HwProcessPciList);
277
278
279 ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
280 "Input PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X\n",
281 PciId->Segment, PciId->Bus, PciId->Device, PciId->Function));
282
283 BusNumber = PciId->Bus;
284
285 /*
286 * Descend down the namespace tree, collecting PCI device, function,
287 * and bus numbers. BusNumber is only important for PCI bridges.
288 * Algorithm: As we descend the tree, use the last valid PCI device,
289 * function, and bus numbers that are discovered, and assign them
290 * to the PCI ID for the target device.
291 */
292 Info = ListHead;
293 while (Info)
294 {
295 Status = AcpiHwGetPciDeviceInfo (PciId, Info->Device,
296 &BusNumber, &IsBridge);
297 if (ACPI_FAILURE (Status))
298 {
299 return (Status);
300 }
301
302 Info = Info->Next;
303 }
304
305 ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
306 "Output PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X "
307 "Status %X BusNumber %X IsBridge %X\n",
308 PciId->Segment, PciId->Bus, PciId->Device, PciId->Function,
309 Status, BusNumber, IsBridge));
310
311 return (AE_OK);
312 }
313
314
315 /*******************************************************************************
316 *
317 * FUNCTION: AcpiHwDeletePciList
318 *
319 * PARAMETERS: ListHead - Device list created by
320 * AcpiHwBuildPciList
321 *
322 * RETURN: None
323 *
324 * DESCRIPTION: Free the entire PCI list.
325 *
326 ******************************************************************************/
327
328 static void
AcpiHwDeletePciList(ACPI_PCI_DEVICE * ListHead)329 AcpiHwDeletePciList (
330 ACPI_PCI_DEVICE *ListHead)
331 {
332 ACPI_PCI_DEVICE *Next;
333 ACPI_PCI_DEVICE *Previous;
334
335
336 Next = ListHead;
337 while (Next)
338 {
339 Previous = Next;
340 Next = Previous->Next;
341 ACPI_FREE (Previous);
342 }
343 }
344
345
346 /*******************************************************************************
347 *
348 * FUNCTION: AcpiHwGetPciDeviceInfo
349 *
350 * PARAMETERS: PciId - Initial values for the PCI ID. May be
351 * modified by this function.
352 * PciDevice - Handle for the PCI device object
353 * BusNumber - Where a PCI bridge bus number is returned
354 * IsBridge - Return value, indicates if this PCI
355 * device is a PCI bridge
356 *
357 * RETURN: Status
358 *
359 * DESCRIPTION: Get the device info for a single PCI device object. Get the
360 * _ADR (contains PCI device and function numbers), and for PCI
361 * bridge devices, get the bus number from PCI configuration
362 * space.
363 *
364 ******************************************************************************/
365
366 static ACPI_STATUS
AcpiHwGetPciDeviceInfo(ACPI_PCI_ID * PciId,ACPI_HANDLE PciDevice,UINT16 * BusNumber,BOOLEAN * IsBridge)367 AcpiHwGetPciDeviceInfo (
368 ACPI_PCI_ID *PciId,
369 ACPI_HANDLE PciDevice,
370 UINT16 *BusNumber,
371 BOOLEAN *IsBridge)
372 {
373 ACPI_STATUS Status;
374 ACPI_OBJECT_TYPE ObjectType;
375 UINT64 ReturnValue;
376 UINT64 PciValue;
377
378
379 /* We only care about objects of type Device */
380
381 Status = AcpiGetType (PciDevice, &ObjectType);
382 if (ACPI_FAILURE (Status))
383 {
384 return (Status);
385 }
386
387 if (ObjectType != ACPI_TYPE_DEVICE)
388 {
389 return (AE_OK);
390 }
391
392 /* We need an _ADR. Ignore device if not present */
393
394 Status = AcpiUtEvaluateNumericObject (METHOD_NAME__ADR,
395 PciDevice, &ReturnValue);
396 if (ACPI_FAILURE (Status))
397 {
398 return (AE_OK);
399 }
400
401 /*
402 * From _ADR, get the PCI Device and Function and
403 * update the PCI ID.
404 */
405 PciId->Device = ACPI_HIWORD (ACPI_LODWORD (ReturnValue));
406 PciId->Function = ACPI_LOWORD (ACPI_LODWORD (ReturnValue));
407
408 /*
409 * If the previous device was a bridge, use the previous
410 * device bus number
411 */
412 if (*IsBridge)
413 {
414 PciId->Bus = *BusNumber;
415 }
416
417 /*
418 * Get the bus numbers from PCI Config space:
419 *
420 * First, get the PCI HeaderType
421 */
422 *IsBridge = FALSE;
423 Status = AcpiOsReadPciConfiguration (PciId,
424 PCI_CFG_HEADER_TYPE_REG, &PciValue, 8);
425 if (ACPI_FAILURE (Status))
426 {
427 return (Status);
428 }
429
430 /* We only care about bridges (1=PciBridge, 2=CardBusBridge) */
431
432 PciValue &= PCI_HEADER_TYPE_MASK;
433
434 if ((PciValue != PCI_TYPE_BRIDGE) &&
435 (PciValue != PCI_TYPE_CARDBUS_BRIDGE))
436 {
437 return (AE_OK);
438 }
439
440 /* Bridge: Get the Primary BusNumber */
441
442 Status = AcpiOsReadPciConfiguration (PciId,
443 PCI_CFG_PRIMARY_BUS_NUMBER_REG, &PciValue, 8);
444 if (ACPI_FAILURE (Status))
445 {
446 return (Status);
447 }
448
449 *IsBridge = TRUE;
450 PciId->Bus = (UINT16) PciValue;
451
452 /* Bridge: Get the Secondary BusNumber */
453
454 Status = AcpiOsReadPciConfiguration (PciId,
455 PCI_CFG_SECONDARY_BUS_NUMBER_REG, &PciValue, 8);
456 if (ACPI_FAILURE (Status))
457 {
458 return (Status);
459 }
460
461 *BusNumber = (UINT16) PciValue;
462 return (AE_OK);
463 }
464