1 /*******************************************************************************
2 *
3 * Module Name: hwpci - Obtain PCI bus, device, and function numbers
4 *
5 ******************************************************************************/
6
7 /*
8 * Copyright (C) 2000 - 2013, 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 MERCHANTIBILITY 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 #define __HWPCI_C__
45
46 #include "acpi.h"
47 #include "accommon.h"
48
49
50 #define _COMPONENT ACPI_NAMESPACE
51 ACPI_MODULE_NAME ("hwpci")
52
53
54 /* PCI configuration space values */
55
56 #define PCI_CFG_HEADER_TYPE_REG 0x0E
57 #define PCI_CFG_PRIMARY_BUS_NUMBER_REG 0x18
58 #define PCI_CFG_SECONDARY_BUS_NUMBER_REG 0x19
59
60 /* PCI header values */
61
62 #define PCI_HEADER_TYPE_MASK 0x7F
63 #define PCI_TYPE_BRIDGE 0x01
64 #define PCI_TYPE_CARDBUS_BRIDGE 0x02
65
66 typedef struct acpi_pci_device
67 {
68 ACPI_HANDLE Device;
69 struct acpi_pci_device *Next;
70
71 } ACPI_PCI_DEVICE;
72
73
74 /* Local prototypes */
75
76 static ACPI_STATUS
77 AcpiHwBuildPciList (
78 ACPI_HANDLE RootPciDevice,
79 ACPI_HANDLE PciRegion,
80 ACPI_PCI_DEVICE **ReturnListHead);
81
82 static ACPI_STATUS
83 AcpiHwProcessPciList (
84 ACPI_PCI_ID *PciId,
85 ACPI_PCI_DEVICE *ListHead);
86
87 static void
88 AcpiHwDeletePciList (
89 ACPI_PCI_DEVICE *ListHead);
90
91 static ACPI_STATUS
92 AcpiHwGetPciDeviceInfo (
93 ACPI_PCI_ID *PciId,
94 ACPI_HANDLE PciDevice,
95 UINT16 *BusNumber,
96 BOOLEAN *IsBridge);
97
98
99 /*******************************************************************************
100 *
101 * FUNCTION: AcpiHwDerivePciId
102 *
103 * PARAMETERS: PciId - Initial values for the PCI ID. May be
104 * modified by this function.
105 * RootPciDevice - A handle to a PCI device object. This
106 * object must be a PCI Root Bridge having a
107 * _HID value of either PNP0A03 or PNP0A08
108 * PciRegion - A handle to a PCI configuration space
109 * Operation Region being initialized
110 *
111 * RETURN: Status
112 *
113 * DESCRIPTION: This function derives a full PCI ID for a PCI device,
114 * consisting of a Segment number, Bus number, Device number,
115 * and function code.
116 *
117 * The PCI hardware dynamically configures PCI bus numbers
118 * depending on the bus topology discovered during system
119 * initialization. This function is invoked during configuration
120 * of a PCI_Config Operation Region in order to (possibly) update
121 * the Bus/Device/Function numbers in the PciId with the actual
122 * values as determined by the hardware and operating system
123 * configuration.
124 *
125 * The PciId parameter is initially populated during the Operation
126 * Region initialization. This function is then called, and is
127 * will make any necessary modifications to the Bus, Device, or
128 * Function number PCI ID subfields as appropriate for the
129 * current hardware and OS configuration.
130 *
131 * NOTE: Created 08/2010. Replaces the previous OSL AcpiOsDerivePciId
132 * interface since this feature is OS-independent. This module
133 * specifically avoids any use of recursion by building a local
134 * temporary device list.
135 *
136 ******************************************************************************/
137
138 ACPI_STATUS
139 AcpiHwDerivePciId (
140 ACPI_PCI_ID *PciId,
141 ACPI_HANDLE RootPciDevice,
142 ACPI_HANDLE PciRegion)
143 {
144 ACPI_STATUS Status;
145 ACPI_PCI_DEVICE *ListHead = NULL;
146
147
148 ACPI_FUNCTION_TRACE (HwDerivePciId);
149
150
151 if (!PciId)
152 {
153 return_ACPI_STATUS (AE_BAD_PARAMETER);
154 }
155
156 /* Build a list of PCI devices, from PciRegion up to RootPciDevice */
157
158 Status = AcpiHwBuildPciList (RootPciDevice, PciRegion, &ListHead);
159 if (ACPI_SUCCESS (Status))
160 {
161 /* Walk the list, updating the PCI device/function/bus numbers */
162
163 Status = AcpiHwProcessPciList (PciId, ListHead);
164 }
165
166 /* Always delete the list */
167
168 AcpiHwDeletePciList (ListHead);
169 return_ACPI_STATUS (Status);
170 }
171
172
173 /*******************************************************************************
174 *
175 * FUNCTION: AcpiHwBuildPciList
176 *
177 * PARAMETERS: RootPciDevice - A handle to a PCI device object. This
178 * object is guaranteed to be a PCI Root
179 * Bridge having a _HID value of either
180 * PNP0A03 or PNP0A08
181 * PciRegion - A handle to the PCI configuration space
182 * Operation Region
183 * ReturnListHead - Where the PCI device list is returned
184 *
185 * RETURN: Status
186 *
187 * DESCRIPTION: Builds a list of devices from the input PCI region up to the
188 * Root PCI device for this namespace subtree.
189 *
190 ******************************************************************************/
191
192 static ACPI_STATUS
193 AcpiHwBuildPciList (
194 ACPI_HANDLE RootPciDevice,
195 ACPI_HANDLE PciRegion,
196 ACPI_PCI_DEVICE **ReturnListHead)
197 {
198 ACPI_HANDLE CurrentDevice;
199 ACPI_HANDLE ParentDevice;
200 ACPI_STATUS Status;
201 ACPI_PCI_DEVICE *ListElement;
202 ACPI_PCI_DEVICE *ListHead = NULL;
203
204
205 /*
206 * Ascend namespace branch until the RootPciDevice is reached, building
207 * a list of device nodes. Loop will exit when either the PCI device is
208 * found, or the root of the namespace is reached.
209 */
210 CurrentDevice = PciRegion;
211 while (1)
212 {
213 Status = AcpiGetParent (CurrentDevice, &ParentDevice);
214 if (ACPI_FAILURE (Status))
215 {
216 return (Status);
217 }
218
219 /* Finished when we reach the PCI root device (PNP0A03 or PNP0A08) */
220
221 if (ParentDevice == RootPciDevice)
222 {
223 *ReturnListHead = ListHead;
224 return (AE_OK);
225 }
226
227 ListElement = ACPI_ALLOCATE (sizeof (ACPI_PCI_DEVICE));
228 if (!ListElement)
229 {
230 return (AE_NO_MEMORY);
231 }
232
233 /* Put new element at the head of the list */
234
235 ListElement->Next = ListHead;
236 ListElement->Device = ParentDevice;
237 ListHead = ListElement;
238
239 CurrentDevice = ParentDevice;
240 }
241 }
242
243
244 /*******************************************************************************
245 *
246 * FUNCTION: AcpiHwProcessPciList
247 *
248 * PARAMETERS: PciId - Initial values for the PCI ID. May be
249 * modified by this function.
250 * ListHead - Device list created by
251 * AcpiHwBuildPciList
252 *
253 * RETURN: Status
254 *
255 * DESCRIPTION: Walk downward through the PCI device list, getting the device
256 * info for each, via the PCI configuration space and updating
257 * the PCI ID as necessary. Deletes the list during traversal.
258 *
259 ******************************************************************************/
260
261 static ACPI_STATUS
262 AcpiHwProcessPciList (
263 ACPI_PCI_ID *PciId,
264 ACPI_PCI_DEVICE *ListHead)
265 {
266 ACPI_STATUS Status = AE_OK;
267 ACPI_PCI_DEVICE *Info;
268 UINT16 BusNumber;
269 BOOLEAN IsBridge = TRUE;
270
271
272 ACPI_FUNCTION_NAME (HwProcessPciList);
273
274
275 ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
276 "Input PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X\n",
277 PciId->Segment, PciId->Bus, PciId->Device, PciId->Function));
278
279 BusNumber = PciId->Bus;
280
281 /*
282 * Descend down the namespace tree, collecting PCI device, function,
283 * and bus numbers. BusNumber is only important for PCI bridges.
284 * Algorithm: As we descend the tree, use the last valid PCI device,
285 * function, and bus numbers that are discovered, and assign them
286 * to the PCI ID for the target device.
287 */
288 Info = ListHead;
289 while (Info)
290 {
291 Status = AcpiHwGetPciDeviceInfo (PciId, Info->Device,
292 &BusNumber, &IsBridge);
293 if (ACPI_FAILURE (Status))
294 {
295 return (Status);
296 }
297
298 Info = Info->Next;
299 }
300
301 ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
302 "Output PciId: Seg %4.4X Bus %4.4X Dev %4.4X Func %4.4X "
303 "Status %X BusNumber %X IsBridge %X\n",
304 PciId->Segment, PciId->Bus, PciId->Device, PciId->Function,
305 Status, BusNumber, IsBridge));
306
307 return (AE_OK);
308 }
309
310
311 /*******************************************************************************
312 *
313 * FUNCTION: AcpiHwDeletePciList
314 *
315 * PARAMETERS: ListHead - Device list created by
316 * AcpiHwBuildPciList
317 *
318 * RETURN: None
319 *
320 * DESCRIPTION: Free the entire PCI list.
321 *
322 ******************************************************************************/
323
324 static void
325 AcpiHwDeletePciList (
326 ACPI_PCI_DEVICE *ListHead)
327 {
328 ACPI_PCI_DEVICE *Next;
329 ACPI_PCI_DEVICE *Previous;
330
331
332 Next = ListHead;
333 while (Next)
334 {
335 Previous = Next;
336 Next = Previous->Next;
337 ACPI_FREE (Previous);
338 }
339 }
340
341
342 /*******************************************************************************
343 *
344 * FUNCTION: AcpiHwGetPciDeviceInfo
345 *
346 * PARAMETERS: PciId - Initial values for the PCI ID. May be
347 * modified by this function.
348 * PciDevice - Handle for the PCI device object
349 * BusNumber - Where a PCI bridge bus number is returned
350 * IsBridge - Return value, indicates if this PCI
351 * device is a PCI bridge
352 *
353 * RETURN: Status
354 *
355 * DESCRIPTION: Get the device info for a single PCI device object. Get the
356 * _ADR (contains PCI device and function numbers), and for PCI
357 * bridge devices, get the bus number from PCI configuration
358 * space.
359 *
360 ******************************************************************************/
361
362 static ACPI_STATUS
363 AcpiHwGetPciDeviceInfo (
364 ACPI_PCI_ID *PciId,
365 ACPI_HANDLE PciDevice,
366 UINT16 *BusNumber,
367 BOOLEAN *IsBridge)
368 {
369 ACPI_STATUS Status;
370 ACPI_OBJECT_TYPE ObjectType;
371 UINT64 ReturnValue;
372 UINT64 PciValue;
373
374
375 /* We only care about objects of type Device */
376
377 Status = AcpiGetType (PciDevice, &ObjectType);
378 if (ACPI_FAILURE (Status))
379 {
380 return (Status);
381 }
382
383 if (ObjectType != ACPI_TYPE_DEVICE)
384 {
385 return (AE_OK);
386 }
387
388 /* We need an _ADR. Ignore device if not present */
389
390 Status = AcpiUtEvaluateNumericObject (METHOD_NAME__ADR,
391 PciDevice, &ReturnValue);
392 if (ACPI_FAILURE (Status))
393 {
394 return (AE_OK);
395 }
396
397 /*
398 * From _ADR, get the PCI Device and Function and
399 * update the PCI ID.
400 */
401 PciId->Device = ACPI_HIWORD (ACPI_LODWORD (ReturnValue));
402 PciId->Function = ACPI_LOWORD (ACPI_LODWORD (ReturnValue));
403
404 /*
405 * If the previous device was a bridge, use the previous
406 * device bus number
407 */
408 if (*IsBridge)
409 {
410 PciId->Bus = *BusNumber;
411 }
412
413 /*
414 * Get the bus numbers from PCI Config space:
415 *
416 * First, get the PCI HeaderType
417 */
418 *IsBridge = FALSE;
419 Status = AcpiOsReadPciConfiguration (PciId,
420 PCI_CFG_HEADER_TYPE_REG, &PciValue, 8);
421 if (ACPI_FAILURE (Status))
422 {
423 return (Status);
424 }
425
426 /* We only care about bridges (1=PciBridge, 2=CardBusBridge) */
427
428 PciValue &= PCI_HEADER_TYPE_MASK;
429
430 if ((PciValue != PCI_TYPE_BRIDGE) &&
431 (PciValue != PCI_TYPE_CARDBUS_BRIDGE))
432 {
433 return (AE_OK);
434 }
435
436 /* Bridge: Get the Primary BusNumber */
437
438 Status = AcpiOsReadPciConfiguration (PciId,
439 PCI_CFG_PRIMARY_BUS_NUMBER_REG, &PciValue, 8);
440 if (ACPI_FAILURE (Status))
441 {
442 return (Status);
443 }
444
445 *IsBridge = TRUE;
446 PciId->Bus = (UINT16) PciValue;
447
448 /* Bridge: Get the Secondary BusNumber */
449
450 Status = AcpiOsReadPciConfiguration (PciId,
451 PCI_CFG_SECONDARY_BUS_NUMBER_REG, &PciValue, 8);
452 if (ACPI_FAILURE (Status))
453 {
454 return (Status);
455 }
456
457 *BusNumber = (UINT16) PciValue;
458 return (AE_OK);
459 }