xref: /freebsd/sys/contrib/dev/acpica/components/tables/tbxfroot.c (revision 3e8eb5c7f4909209c042403ddee340b2ee7003a5)
1 /******************************************************************************
2  *
3  * Module Name: tbxfroot - Find the root ACPI table (RSDT)
4  *
5  *****************************************************************************/
6 
7 /******************************************************************************
8  *
9  * 1. Copyright Notice
10  *
11  * Some or all of this work - Copyright (c) 1999 - 2022, Intel Corp.
12  * All rights reserved.
13  *
14  * 2. License
15  *
16  * 2.1. This is your license from Intel Corp. under its intellectual property
17  * rights. You may have additional license terms from the party that provided
18  * you this software, covering your right to use that party's intellectual
19  * property rights.
20  *
21  * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a
22  * copy of the source code appearing in this file ("Covered Code") an
23  * irrevocable, perpetual, worldwide license under Intel's copyrights in the
24  * base code distributed originally by Intel ("Original Intel Code") to copy,
25  * make derivatives, distribute, use and display any portion of the Covered
26  * Code in any form, with the right to sublicense such rights; and
27  *
28  * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent
29  * license (with the right to sublicense), under only those claims of Intel
30  * patents that are infringed by the Original Intel Code, to make, use, sell,
31  * offer to sell, and import the Covered Code and derivative works thereof
32  * solely to the minimum extent necessary to exercise the above copyright
33  * license, and in no event shall the patent license extend to any additions
34  * to or modifications of the Original Intel Code. No other license or right
35  * is granted directly or by implication, estoppel or otherwise;
36  *
37  * The above copyright and patent license is granted only if the following
38  * conditions are met:
39  *
40  * 3. Conditions
41  *
42  * 3.1. Redistribution of Source with Rights to Further Distribute Source.
43  * Redistribution of source code of any substantial portion of the Covered
44  * Code or modification with rights to further distribute source must include
45  * the above Copyright Notice, the above License, this list of Conditions,
46  * and the following Disclaimer and Export Compliance provision. In addition,
47  * Licensee must cause all Covered Code to which Licensee contributes to
48  * contain a file documenting the changes Licensee made to create that Covered
49  * Code and the date of any change. Licensee must include in that file the
50  * documentation of any changes made by any predecessor Licensee. Licensee
51  * must include a prominent statement that the modification is derived,
52  * directly or indirectly, from Original Intel Code.
53  *
54  * 3.2. Redistribution of Source with no Rights to Further Distribute Source.
55  * Redistribution of source code of any substantial portion of the Covered
56  * Code or modification without rights to further distribute source must
57  * include the following Disclaimer and Export Compliance provision in the
58  * documentation and/or other materials provided with distribution. In
59  * addition, Licensee may not authorize further sublicense of source of any
60  * portion of the Covered Code, and must include terms to the effect that the
61  * license from Licensee to its licensee is limited to the intellectual
62  * property embodied in the software Licensee provides to its licensee, and
63  * not to intellectual property embodied in modifications its licensee may
64  * make.
65  *
66  * 3.3. Redistribution of Executable. Redistribution in executable form of any
67  * substantial portion of the Covered Code or modification must reproduce the
68  * above Copyright Notice, and the following Disclaimer and Export Compliance
69  * provision in the documentation and/or other materials provided with the
70  * distribution.
71  *
72  * 3.4. Intel retains all right, title, and interest in and to the Original
73  * Intel Code.
74  *
75  * 3.5. Neither the name Intel nor any other trademark owned or controlled by
76  * Intel shall be used in advertising or otherwise to promote the sale, use or
77  * other dealings in products derived from or relating to the Covered Code
78  * without prior written authorization from Intel.
79  *
80  * 4. Disclaimer and Export Compliance
81  *
82  * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED
83  * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE
84  * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE,
85  * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY
86  * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY
87  * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A
88  * PARTICULAR PURPOSE.
89  *
90  * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES
91  * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR
92  * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT,
93  * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY
94  * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL
95  * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS
96  * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY
97  * LIMITED REMEDY.
98  *
99  * 4.3. Licensee shall not export, either directly or indirectly, any of this
100  * software or system incorporating such software without first obtaining any
101  * required license or other approval from the U. S. Department of Commerce or
102  * any other agency or department of the United States Government. In the
103  * event Licensee exports any such software from the United States or
104  * re-exports any such software from a foreign destination, Licensee shall
105  * ensure that the distribution and export/re-export of the software is in
106  * compliance with all laws, regulations, orders, or other restrictions of the
107  * U.S. Export Administration Regulations. Licensee agrees that neither it nor
108  * any of its subsidiaries will export/re-export any technical data, process,
109  * software, or service, directly or indirectly, to any country for which the
110  * United States government or any agency thereof requires an export license,
111  * other governmental approval, or letter of assurance, without first obtaining
112  * such license, approval or letter.
113  *
114  *****************************************************************************
115  *
116  * Alternatively, you may choose to be licensed under the terms of the
117  * following license:
118  *
119  * Redistribution and use in source and binary forms, with or without
120  * modification, are permitted provided that the following conditions
121  * are met:
122  * 1. Redistributions of source code must retain the above copyright
123  *    notice, this list of conditions, and the following disclaimer,
124  *    without modification.
125  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
126  *    substantially similar to the "NO WARRANTY" disclaimer below
127  *    ("Disclaimer") and any redistribution must be conditioned upon
128  *    including a substantially similar Disclaimer requirement for further
129  *    binary redistribution.
130  * 3. Neither the names of the above-listed copyright holders nor the names
131  *    of any contributors may be used to endorse or promote products derived
132  *    from this software without specific prior written permission.
133  *
134  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
135  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
136  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
137  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
138  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
139  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
140  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
141  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
142  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
143  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
144  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
145  *
146  * Alternatively, you may choose to be licensed under the terms of the
147  * GNU General Public License ("GPL") version 2 as published by the Free
148  * Software Foundation.
149  *
150  *****************************************************************************/
151 
152 #include <contrib/dev/acpica/include/acpi.h>
153 #include <contrib/dev/acpica/include/accommon.h>
154 #include <contrib/dev/acpica/include/actables.h>
155 
156 
157 #define _COMPONENT          ACPI_TABLES
158         ACPI_MODULE_NAME    ("tbxfroot")
159 
160 
161 /*******************************************************************************
162  *
163  * FUNCTION:    AcpiTbGetRsdpLength
164  *
165  * PARAMETERS:  Rsdp                - Pointer to RSDP
166  *
167  * RETURN:      Table length
168  *
169  * DESCRIPTION: Get the length of the RSDP
170  *
171  ******************************************************************************/
172 
173 UINT32
174 AcpiTbGetRsdpLength (
175     ACPI_TABLE_RSDP         *Rsdp)
176 {
177 
178     if (!ACPI_VALIDATE_RSDP_SIG (Rsdp->Signature))
179     {
180         /* BAD Signature */
181 
182         return (0);
183     }
184 
185     /* "Length" field is available if table version >= 2 */
186 
187     if (Rsdp->Revision >= 2)
188     {
189         return (Rsdp->Length);
190     }
191     else
192     {
193         return (ACPI_RSDP_CHECKSUM_LENGTH);
194     }
195 }
196 
197 
198 /*******************************************************************************
199  *
200  * FUNCTION:    AcpiTbValidateRsdp
201  *
202  * PARAMETERS:  Rsdp                - Pointer to unvalidated RSDP
203  *
204  * RETURN:      Status
205  *
206  * DESCRIPTION: Validate the RSDP (ptr)
207  *
208  ******************************************************************************/
209 
210 ACPI_STATUS
211 AcpiTbValidateRsdp (
212     ACPI_TABLE_RSDP         *Rsdp)
213 {
214 
215     /*
216      * The signature and checksum must both be correct
217      *
218      * Note: Sometimes there exists more than one RSDP in memory; the valid
219      * RSDP has a valid checksum, all others have an invalid checksum.
220      */
221     if (!ACPI_VALIDATE_RSDP_SIG (Rsdp->Signature))
222     {
223         /* Nope, BAD Signature */
224 
225         return (AE_BAD_SIGNATURE);
226     }
227 
228     /* Check the standard checksum */
229 
230     if (AcpiTbChecksum ((UINT8 *) Rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0)
231     {
232         return (AE_BAD_CHECKSUM);
233     }
234 
235     /* Check extended checksum if table version >= 2 */
236 
237     if ((Rsdp->Revision >= 2) &&
238         (AcpiTbChecksum ((UINT8 *) Rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0))
239     {
240         return (AE_BAD_CHECKSUM);
241     }
242 
243     return (AE_OK);
244 }
245 
246 
247 /*******************************************************************************
248  *
249  * FUNCTION:    AcpiFindRootPointer
250  *
251  * PARAMETERS:  TableAddress            - Where the table pointer is returned
252  *
253  * RETURN:      Status, RSDP physical address
254  *
255  * DESCRIPTION: Search lower 1Mbyte of memory for the root system descriptor
256  *              pointer structure. If it is found, set *RSDP to point to it.
257  *
258  * NOTE1:       The RSDP must be either in the first 1K of the Extended
259  *              BIOS Data Area or between E0000 and FFFFF (From ACPI Spec.)
260  *              Only a 32-bit physical address is necessary.
261  *
262  * NOTE2:       This function is always available, regardless of the
263  *              initialization state of the rest of ACPI.
264  *
265  ******************************************************************************/
266 
267 ACPI_STATUS ACPI_INIT_FUNCTION
268 AcpiFindRootPointer (
269     ACPI_PHYSICAL_ADDRESS   *TableAddress)
270 {
271     UINT8                   *TablePtr;
272     UINT8                   *MemRover;
273     UINT32                  PhysicalAddress;
274 
275 
276     ACPI_FUNCTION_TRACE (AcpiFindRootPointer);
277 
278 
279     /* 1a) Get the location of the Extended BIOS Data Area (EBDA) */
280 
281     TablePtr = AcpiOsMapMemory (
282         (ACPI_PHYSICAL_ADDRESS) ACPI_EBDA_PTR_LOCATION,
283         ACPI_EBDA_PTR_LENGTH);
284     if (!TablePtr)
285     {
286         ACPI_ERROR ((AE_INFO,
287             "Could not map memory at 0x%8.8X for length %u",
288             ACPI_EBDA_PTR_LOCATION, ACPI_EBDA_PTR_LENGTH));
289 
290         return_ACPI_STATUS (AE_NO_MEMORY);
291     }
292 
293     ACPI_MOVE_16_TO_32 (&PhysicalAddress, TablePtr);
294 
295     /* Convert segment part to physical address */
296 
297     PhysicalAddress <<= 4;
298     AcpiOsUnmapMemory (TablePtr, ACPI_EBDA_PTR_LENGTH);
299 
300     /* EBDA present? */
301 
302     if (PhysicalAddress > 0x400)
303     {
304         /*
305          * 1b) Search EBDA paragraphs (EBDA is required to be a
306          *     minimum of 1K length)
307          */
308         TablePtr = AcpiOsMapMemory (
309             (ACPI_PHYSICAL_ADDRESS) PhysicalAddress,
310             ACPI_EBDA_WINDOW_SIZE);
311         if (!TablePtr)
312         {
313             ACPI_ERROR ((AE_INFO,
314                 "Could not map memory at 0x%8.8X for length %u",
315                 PhysicalAddress, ACPI_EBDA_WINDOW_SIZE));
316 
317             return_ACPI_STATUS (AE_NO_MEMORY);
318         }
319 
320         MemRover = AcpiTbScanMemoryForRsdp (
321             TablePtr, ACPI_EBDA_WINDOW_SIZE);
322         AcpiOsUnmapMemory (TablePtr, ACPI_EBDA_WINDOW_SIZE);
323 
324         if (MemRover)
325         {
326             /* Return the physical address */
327 
328             PhysicalAddress +=
329                 (UINT32) ACPI_PTR_DIFF (MemRover, TablePtr);
330 
331             *TableAddress = (ACPI_PHYSICAL_ADDRESS) PhysicalAddress;
332             return_ACPI_STATUS (AE_OK);
333         }
334     }
335 
336     /*
337      * 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
338      */
339     TablePtr = AcpiOsMapMemory (
340         (ACPI_PHYSICAL_ADDRESS) ACPI_HI_RSDP_WINDOW_BASE,
341         ACPI_HI_RSDP_WINDOW_SIZE);
342 
343     if (!TablePtr)
344     {
345         ACPI_ERROR ((AE_INFO,
346             "Could not map memory at 0x%8.8X for length %u",
347             ACPI_HI_RSDP_WINDOW_BASE, ACPI_HI_RSDP_WINDOW_SIZE));
348 
349         return_ACPI_STATUS (AE_NO_MEMORY);
350     }
351 
352     MemRover = AcpiTbScanMemoryForRsdp (
353         TablePtr, ACPI_HI_RSDP_WINDOW_SIZE);
354     AcpiOsUnmapMemory (TablePtr, ACPI_HI_RSDP_WINDOW_SIZE);
355 
356     if (MemRover)
357     {
358         /* Return the physical address */
359 
360         PhysicalAddress = (UINT32)
361             (ACPI_HI_RSDP_WINDOW_BASE + ACPI_PTR_DIFF (MemRover, TablePtr));
362 
363         *TableAddress = (ACPI_PHYSICAL_ADDRESS) PhysicalAddress;
364         return_ACPI_STATUS (AE_OK);
365     }
366 
367     /* A valid RSDP was not found */
368 
369     ACPI_BIOS_ERROR ((AE_INFO, "A valid RSDP was not found"));
370     return_ACPI_STATUS (AE_NOT_FOUND);
371 }
372 
373 ACPI_EXPORT_SYMBOL_INIT (AcpiFindRootPointer)
374 
375 
376 /*******************************************************************************
377  *
378  * FUNCTION:    AcpiTbScanMemoryForRsdp
379  *
380  * PARAMETERS:  StartAddress        - Starting pointer for search
381  *              Length              - Maximum length to search
382  *
383  * RETURN:      Pointer to the RSDP if found, otherwise NULL.
384  *
385  * DESCRIPTION: Search a block of memory for the RSDP signature
386  *
387  ******************************************************************************/
388 
389 UINT8 *
390 AcpiTbScanMemoryForRsdp (
391     UINT8                   *StartAddress,
392     UINT32                  Length)
393 {
394     ACPI_STATUS             Status;
395     UINT8                   *MemRover;
396     UINT8                   *EndAddress;
397 
398 
399     ACPI_FUNCTION_TRACE (TbScanMemoryForRsdp);
400 
401 
402     EndAddress = StartAddress + Length;
403 
404     /* Search from given start address for the requested length */
405 
406     for (MemRover = StartAddress; MemRover < EndAddress;
407          MemRover += ACPI_RSDP_SCAN_STEP)
408     {
409         /* The RSDP signature and checksum must both be correct */
410 
411         Status = AcpiTbValidateRsdp (
412             ACPI_CAST_PTR (ACPI_TABLE_RSDP, MemRover));
413         if (ACPI_SUCCESS (Status))
414         {
415             /* Sig and checksum valid, we have found a real RSDP */
416 
417             ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
418                 "RSDP located at physical address %p\n", MemRover));
419             return_PTR (MemRover);
420         }
421 
422         /* No sig match or bad checksum, keep searching */
423     }
424 
425     /* Searched entire block, no RSDP was found */
426 
427     ACPI_DEBUG_PRINT ((ACPI_DB_INFO,
428         "Searched entire block from %p, valid RSDP was not found\n",
429         StartAddress));
430     return_PTR (NULL);
431 }
432