1 /******************************************************************************
2  *
3  * Module Name: evhandler - Support for Address Space handlers
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 #include "acevents.h"
47 #include "acnamesp.h"
48 #include "acinterp.h"
49 
50 #define _COMPONENT          ACPI_EVENTS
51         ACPI_MODULE_NAME    ("evhandler")
52 
53 
54 /* Local prototypes */
55 
56 static ACPI_STATUS
57 AcpiEvInstallHandler (
58     ACPI_HANDLE             ObjHandle,
59     UINT32                  Level,
60     void                    *Context,
61     void                    **ReturnValue);
62 
63 
64 /* These are the address spaces that will get default handlers */
65 
66 UINT8        AcpiGbl_DefaultAddressSpaces[ACPI_NUM_DEFAULT_SPACES] =
67 {
68     ACPI_ADR_SPACE_SYSTEM_MEMORY,
69     ACPI_ADR_SPACE_SYSTEM_IO,
70     ACPI_ADR_SPACE_PCI_CONFIG,
71     ACPI_ADR_SPACE_DATA_TABLE
72 };
73 
74 
75 /*******************************************************************************
76  *
77  * FUNCTION:    AcpiEvInstallRegionHandlers
78  *
79  * PARAMETERS:  None
80  *
81  * RETURN:      Status
82  *
83  * DESCRIPTION: Installs the core subsystem default address space handlers.
84  *
85  ******************************************************************************/
86 
87 ACPI_STATUS
AcpiEvInstallRegionHandlers(void)88 AcpiEvInstallRegionHandlers (
89     void)
90 {
91     ACPI_STATUS             Status;
92     UINT32                  i;
93 
94 
95     ACPI_FUNCTION_TRACE (EvInstallRegionHandlers);
96 
97 
98     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
99     if (ACPI_FAILURE (Status))
100     {
101         return_ACPI_STATUS (Status);
102     }
103 
104     /*
105      * All address spaces (PCI Config, EC, SMBus) are scope dependent and
106      * registration must occur for a specific device.
107      *
108      * In the case of the system memory and IO address spaces there is
109      * currently no device associated with the address space. For these we
110      * use the root.
111      *
112      * We install the default PCI config space handler at the root so that
113      * this space is immediately available even though the we have not
114      * enumerated all the PCI Root Buses yet. This is to conform to the ACPI
115      * specification which states that the PCI config space must be always
116      * available -- even though we are nowhere near ready to find the PCI root
117      * buses at this point.
118      *
119      * NOTE: We ignore AE_ALREADY_EXISTS because this means that a handler
120      * has already been installed (via AcpiInstallAddressSpaceHandler).
121      * Similar for AE_SAME_HANDLER.
122      */
123     for (i = 0; i < ACPI_NUM_DEFAULT_SPACES; i++)
124     {
125         Status = AcpiEvInstallSpaceHandler (AcpiGbl_RootNode,
126             AcpiGbl_DefaultAddressSpaces[i],
127             ACPI_DEFAULT_HANDLER, NULL, NULL);
128         switch (Status)
129         {
130         case AE_OK:
131         case AE_SAME_HANDLER:
132         case AE_ALREADY_EXISTS:
133 
134             /* These exceptions are all OK */
135 
136             Status = AE_OK;
137             break;
138 
139         default:
140 
141             goto UnlockAndExit;
142         }
143     }
144 
145 UnlockAndExit:
146     (void) AcpiUtReleaseMutex (ACPI_MTX_NAMESPACE);
147     return_ACPI_STATUS (Status);
148 }
149 
150 
151 /*******************************************************************************
152  *
153  * FUNCTION:    AcpiEvHasDefaultHandler
154  *
155  * PARAMETERS:  Node                - Namespace node for the device
156  *              SpaceId             - The address space ID
157  *
158  * RETURN:      TRUE if default handler is installed, FALSE otherwise
159  *
160  * DESCRIPTION: Check if the default handler is installed for the requested
161  *              space ID.
162  *
163  ******************************************************************************/
164 
165 BOOLEAN
AcpiEvHasDefaultHandler(ACPI_NAMESPACE_NODE * Node,ACPI_ADR_SPACE_TYPE SpaceId)166 AcpiEvHasDefaultHandler (
167     ACPI_NAMESPACE_NODE     *Node,
168     ACPI_ADR_SPACE_TYPE     SpaceId)
169 {
170     ACPI_OPERAND_OBJECT     *ObjDesc;
171     ACPI_OPERAND_OBJECT     *HandlerObj;
172 
173 
174     /* Must have an existing internal object */
175 
176     ObjDesc = AcpiNsGetAttachedObject (Node);
177     if (ObjDesc)
178     {
179         HandlerObj = ObjDesc->CommonNotify.Handler;
180 
181         /* Walk the linked list of handlers for this object */
182 
183         while (HandlerObj)
184         {
185             if (HandlerObj->AddressSpace.SpaceId == SpaceId)
186             {
187                 if (HandlerObj->AddressSpace.HandlerFlags &
188                     ACPI_ADDR_HANDLER_DEFAULT_INSTALLED)
189                 {
190                     return (TRUE);
191                 }
192             }
193 
194             HandlerObj = HandlerObj->AddressSpace.Next;
195         }
196     }
197 
198     return (FALSE);
199 }
200 
201 
202 /*******************************************************************************
203  *
204  * FUNCTION:    AcpiEvInstallHandler
205  *
206  * PARAMETERS:  WalkNamespace callback
207  *
208  * DESCRIPTION: This routine installs an address handler into objects that are
209  *              of type Region or Device.
210  *
211  *              If the Object is a Device, and the device has a handler of
212  *              the same type then the search is terminated in that branch.
213  *
214  *              This is because the existing handler is closer in proximity
215  *              to any more regions than the one we are trying to install.
216  *
217  ******************************************************************************/
218 
219 static ACPI_STATUS
AcpiEvInstallHandler(ACPI_HANDLE ObjHandle,UINT32 Level,void * Context,void ** ReturnValue)220 AcpiEvInstallHandler (
221     ACPI_HANDLE             ObjHandle,
222     UINT32                  Level,
223     void                    *Context,
224     void                    **ReturnValue)
225 {
226     ACPI_OPERAND_OBJECT     *HandlerObj;
227     ACPI_OPERAND_OBJECT     *NextHandlerObj;
228     ACPI_OPERAND_OBJECT     *ObjDesc;
229     ACPI_NAMESPACE_NODE     *Node;
230     ACPI_STATUS             Status;
231 
232 
233     ACPI_FUNCTION_NAME (EvInstallHandler);
234 
235 
236     HandlerObj = (ACPI_OPERAND_OBJECT  *) Context;
237 
238     /* Parameter validation */
239 
240     if (!HandlerObj)
241     {
242         return (AE_OK);
243     }
244 
245     /* Convert and validate the device handle */
246 
247     Node = AcpiNsValidateHandle (ObjHandle);
248     if (!Node)
249     {
250         return (AE_BAD_PARAMETER);
251     }
252 
253     /*
254      * We only care about regions and objects that are allowed to have
255      * address space handlers
256      */
257     if ((Node->Type != ACPI_TYPE_DEVICE) &&
258         (Node->Type != ACPI_TYPE_REGION) &&
259         (Node != AcpiGbl_RootNode))
260     {
261         return (AE_OK);
262     }
263 
264     /* Check for an existing internal object */
265 
266     ObjDesc = AcpiNsGetAttachedObject (Node);
267     if (!ObjDesc)
268     {
269         /* No object, just exit */
270 
271         return (AE_OK);
272     }
273 
274     /* Devices are handled different than regions */
275 
276     if (ObjDesc->Common.Type == ACPI_TYPE_DEVICE)
277     {
278         /* Check if this Device already has a handler for this address space */
279 
280         NextHandlerObj = AcpiEvFindRegionHandler (
281             HandlerObj->AddressSpace.SpaceId, ObjDesc->CommonNotify.Handler);
282         if (NextHandlerObj)
283         {
284             /* Found a handler, is it for the same address space? */
285 
286             ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
287                 "Found handler for region [%s] in device %p(%p) handler %p\n",
288                 AcpiUtGetRegionName (HandlerObj->AddressSpace.SpaceId),
289                 ObjDesc, NextHandlerObj, HandlerObj));
290 
291             /*
292              * Since the object we found it on was a device, then it means
293              * that someone has already installed a handler for the branch
294              * of the namespace from this device on. Just bail out telling
295              * the walk routine to not traverse this branch. This preserves
296              * the scoping rule for handlers.
297              */
298             return (AE_CTRL_DEPTH);
299         }
300 
301         /*
302          * As long as the device didn't have a handler for this space we
303          * don't care about it. We just ignore it and proceed.
304          */
305         return (AE_OK);
306     }
307 
308     /* Object is a Region */
309 
310     if (ObjDesc->Region.SpaceId != HandlerObj->AddressSpace.SpaceId)
311     {
312         /* This region is for a different address space, just ignore it */
313 
314         return (AE_OK);
315     }
316 
317     /*
318      * Now we have a region and it is for the handler's address space type.
319      *
320      * First disconnect region for any previous handler (if any)
321      */
322     AcpiEvDetachRegion (ObjDesc, FALSE);
323 
324     /* Connect the region to the new handler */
325 
326     Status = AcpiEvAttachRegion (HandlerObj, ObjDesc, FALSE);
327     return (Status);
328 }
329 
330 
331 /*******************************************************************************
332  *
333  * FUNCTION:    AcpiEvFindRegionHandler
334  *
335  * PARAMETERS:  SpaceId         - The address space ID
336  *              HandlerObj      - Head of the handler object list
337  *
338  * RETURN:      Matching handler object. NULL if space ID not matched
339  *
340  * DESCRIPTION: Search a handler object list for a match on the address
341  *              space ID.
342  *
343  ******************************************************************************/
344 
345 ACPI_OPERAND_OBJECT *
AcpiEvFindRegionHandler(ACPI_ADR_SPACE_TYPE SpaceId,ACPI_OPERAND_OBJECT * HandlerObj)346 AcpiEvFindRegionHandler (
347     ACPI_ADR_SPACE_TYPE     SpaceId,
348     ACPI_OPERAND_OBJECT     *HandlerObj)
349 {
350 
351     /* Walk the handler list for this device */
352 
353     while (HandlerObj)
354     {
355         /* Same SpaceId indicates a handler is installed */
356 
357         if (HandlerObj->AddressSpace.SpaceId == SpaceId)
358         {
359             return (HandlerObj);
360         }
361 
362         /* Next handler object */
363 
364         HandlerObj = HandlerObj->AddressSpace.Next;
365     }
366 
367     return (NULL);
368 }
369 
370 
371 /*******************************************************************************
372  *
373  * FUNCTION:    AcpiEvInstallSpaceHandler
374  *
375  * PARAMETERS:  Node            - Namespace node for the device
376  *              SpaceId         - The address space ID
377  *              Handler         - Address of the handler
378  *              Setup           - Address of the setup function
379  *              Context         - Value passed to the handler on each access
380  *
381  * RETURN:      Status
382  *
383  * DESCRIPTION: Install a handler for all OpRegions of a given SpaceId.
384  *              Assumes namespace is locked
385  *
386  ******************************************************************************/
387 
388 ACPI_STATUS
AcpiEvInstallSpaceHandler(ACPI_NAMESPACE_NODE * Node,ACPI_ADR_SPACE_TYPE SpaceId,ACPI_ADR_SPACE_HANDLER Handler,ACPI_ADR_SPACE_SETUP Setup,void * Context)389 AcpiEvInstallSpaceHandler (
390     ACPI_NAMESPACE_NODE     *Node,
391     ACPI_ADR_SPACE_TYPE     SpaceId,
392     ACPI_ADR_SPACE_HANDLER  Handler,
393     ACPI_ADR_SPACE_SETUP    Setup,
394     void                    *Context)
395 {
396     ACPI_OPERAND_OBJECT     *ObjDesc;
397     ACPI_OPERAND_OBJECT     *HandlerObj;
398     ACPI_STATUS             Status = AE_OK;
399     ACPI_OBJECT_TYPE        Type;
400     UINT8                   Flags = 0;
401 
402 
403     ACPI_FUNCTION_TRACE (EvInstallSpaceHandler);
404 
405 
406     /*
407      * This registration is valid for only the types below and the root.
408      * The root node is where the default handlers get installed.
409      */
410     if ((Node->Type != ACPI_TYPE_DEVICE)     &&
411         (Node->Type != ACPI_TYPE_PROCESSOR)  &&
412         (Node->Type != ACPI_TYPE_THERMAL)    &&
413         (Node != AcpiGbl_RootNode))
414     {
415         Status = AE_BAD_PARAMETER;
416         goto UnlockAndExit;
417     }
418 
419     if (Handler == ACPI_DEFAULT_HANDLER)
420     {
421         Flags = ACPI_ADDR_HANDLER_DEFAULT_INSTALLED;
422 
423         switch (SpaceId)
424         {
425         case ACPI_ADR_SPACE_SYSTEM_MEMORY:
426 
427             Handler = AcpiExSystemMemorySpaceHandler;
428             Setup   = AcpiEvSystemMemoryRegionSetup;
429             break;
430 
431         case ACPI_ADR_SPACE_SYSTEM_IO:
432 
433             Handler = AcpiExSystemIoSpaceHandler;
434             Setup   = AcpiEvIoSpaceRegionSetup;
435             break;
436 
437         case ACPI_ADR_SPACE_PCI_CONFIG:
438 
439             Handler = AcpiExPciConfigSpaceHandler;
440             Setup   = AcpiEvPciConfigRegionSetup;
441             break;
442 
443         case ACPI_ADR_SPACE_CMOS:
444 
445             Handler = AcpiExCmosSpaceHandler;
446             Setup   = AcpiEvCmosRegionSetup;
447             break;
448 
449         case ACPI_ADR_SPACE_PCI_BAR_TARGET:
450 
451             Handler = AcpiExPciBarSpaceHandler;
452             Setup   = AcpiEvPciBarRegionSetup;
453             break;
454 
455         case ACPI_ADR_SPACE_DATA_TABLE:
456 
457             Handler = AcpiExDataTableSpaceHandler;
458             Setup   = AcpiEvDataTableRegionSetup;
459             break;
460 
461         default:
462 
463             Status = AE_BAD_PARAMETER;
464             goto UnlockAndExit;
465         }
466     }
467 
468     /* If the caller hasn't specified a setup routine, use the default */
469 
470     if (!Setup)
471     {
472         Setup = AcpiEvDefaultRegionSetup;
473     }
474 
475     /* Check for an existing internal object */
476 
477     ObjDesc = AcpiNsGetAttachedObject (Node);
478     if (ObjDesc)
479     {
480         /*
481          * The attached device object already exists. Now make sure
482          * the handler is not already installed.
483          */
484         HandlerObj = AcpiEvFindRegionHandler (SpaceId,
485             ObjDesc->CommonNotify.Handler);
486 
487         if (HandlerObj)
488         {
489             if (HandlerObj->AddressSpace.Handler == Handler)
490             {
491                 /*
492                  * It is (relatively) OK to attempt to install the SAME
493                  * handler twice. This can easily happen with the
494                  * PCI_Config space.
495                  */
496                 Status = AE_SAME_HANDLER;
497                 goto UnlockAndExit;
498             }
499             else
500             {
501                 /* A handler is already installed */
502 
503                 Status = AE_ALREADY_EXISTS;
504             }
505 
506             goto UnlockAndExit;
507         }
508     }
509     else
510     {
511         ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
512             "Creating object on Device %p while installing handler\n",
513             Node));
514 
515         /* ObjDesc does not exist, create one */
516 
517         if (Node->Type == ACPI_TYPE_ANY)
518         {
519             Type = ACPI_TYPE_DEVICE;
520         }
521         else
522         {
523             Type = Node->Type;
524         }
525 
526         ObjDesc = AcpiUtCreateInternalObject (Type);
527         if (!ObjDesc)
528         {
529             Status = AE_NO_MEMORY;
530             goto UnlockAndExit;
531         }
532 
533         /* Init new descriptor */
534 
535         ObjDesc->Common.Type = (UINT8) Type;
536 
537         /* Attach the new object to the Node */
538 
539         Status = AcpiNsAttachObject (Node, ObjDesc, Type);
540 
541         /* Remove local reference to the object */
542 
543         AcpiUtRemoveReference (ObjDesc);
544 
545         if (ACPI_FAILURE (Status))
546         {
547             goto UnlockAndExit;
548         }
549     }
550 
551     ACPI_DEBUG_PRINT ((ACPI_DB_OPREGION,
552         "Installing address handler for region %s(%X) "
553         "on Device %4.4s %p(%p)\n",
554         AcpiUtGetRegionName (SpaceId), SpaceId,
555         AcpiUtGetNodeName (Node), Node, ObjDesc));
556 
557     /*
558      * Install the handler
559      *
560      * At this point there is no existing handler. Just allocate the object
561      * for the handler and link it into the list.
562      */
563     HandlerObj = AcpiUtCreateInternalObject (ACPI_TYPE_LOCAL_ADDRESS_HANDLER);
564     if (!HandlerObj)
565     {
566         Status = AE_NO_MEMORY;
567         goto UnlockAndExit;
568     }
569 
570     /* Init handler obj */
571 
572     Status = AcpiOsCreateMutex (&HandlerObj->AddressSpace.ContextMutex);
573     if (ACPI_FAILURE (Status))
574     {
575         AcpiUtRemoveReference (HandlerObj);
576         goto UnlockAndExit;
577     }
578 
579     HandlerObj->AddressSpace.SpaceId = (UINT8) SpaceId;
580     HandlerObj->AddressSpace.HandlerFlags = Flags;
581     HandlerObj->AddressSpace.RegionList = NULL;
582     HandlerObj->AddressSpace.Node = Node;
583     HandlerObj->AddressSpace.Handler = Handler;
584     HandlerObj->AddressSpace.Context = Context;
585     HandlerObj->AddressSpace.Setup = Setup;
586 
587     /* Install at head of Device.AddressSpace list */
588 
589     HandlerObj->AddressSpace.Next = ObjDesc->CommonNotify.Handler;
590 
591     /*
592      * The Device object is the first reference on the HandlerObj.
593      * Each region that uses the handler adds a reference.
594      */
595     ObjDesc->CommonNotify.Handler = HandlerObj;
596 
597     /*
598      * Walk the namespace finding all of the regions this handler will
599      * manage.
600      *
601      * Start at the device and search the branch toward the leaf nodes
602      * until either the leaf is encountered or a device is detected that
603      * has an address handler of the same type.
604      *
605      * In either case, back up and search down the remainder of the branch
606      */
607     Status = AcpiNsWalkNamespace (ACPI_TYPE_ANY, Node,
608         ACPI_UINT32_MAX, ACPI_NS_WALK_UNLOCK,
609         AcpiEvInstallHandler, NULL, HandlerObj, NULL);
610 
611 UnlockAndExit:
612     return_ACPI_STATUS (Status);
613 }
614