ReactOS 0.4.15-dev-5667-ged97270
tbxfroot.c
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1/******************************************************************************
2 *
3 * Module Name: tbxfroot - Find the root ACPI table (RSDT)
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 "actables.h"
47
48
49#define _COMPONENT ACPI_TABLES
50 ACPI_MODULE_NAME ("tbxfroot")
51
52
53/*******************************************************************************
54 *
55 * FUNCTION: AcpiTbGetRsdpLength
56 *
57 * PARAMETERS: Rsdp - Pointer to RSDP
58 *
59 * RETURN: Table length
60 *
61 * DESCRIPTION: Get the length of the RSDP
62 *
63 ******************************************************************************/
64
67 ACPI_TABLE_RSDP *Rsdp)
68{
69
70 if (!ACPI_VALIDATE_RSDP_SIG (Rsdp->Signature))
71 {
72 /* BAD Signature */
73
74 return (0);
75 }
76
77 /* "Length" field is available if table version >= 2 */
78
79 if (Rsdp->Revision >= 2)
80 {
81 return (Rsdp->Length);
82 }
83 else
84 {
86 }
87}
88
89
90/*******************************************************************************
91 *
92 * FUNCTION: AcpiTbValidateRsdp
93 *
94 * PARAMETERS: Rsdp - Pointer to unvalidated RSDP
95 *
96 * RETURN: Status
97 *
98 * DESCRIPTION: Validate the RSDP (ptr)
99 *
100 ******************************************************************************/
101
104 ACPI_TABLE_RSDP *Rsdp)
105{
106
107 /*
108 * The signature and checksum must both be correct
109 *
110 * Note: Sometimes there exists more than one RSDP in memory; the valid
111 * RSDP has a valid checksum, all others have an invalid checksum.
112 */
114 {
115 /* Nope, BAD Signature */
116
117 return (AE_BAD_SIGNATURE);
118 }
119
120 /* Check the standard checksum */
121
123 {
124 return (AE_BAD_CHECKSUM);
125 }
126
127 /* Check extended checksum if table version >= 2 */
128
129 if ((Rsdp->Revision >= 2) &&
131 {
132 return (AE_BAD_CHECKSUM);
133 }
134
135 return (AE_OK);
136}
137
138
139/*******************************************************************************
140 *
141 * FUNCTION: AcpiFindRootPointer
142 *
143 * PARAMETERS: TableAddress - Where the table pointer is returned
144 *
145 * RETURN: Status, RSDP physical address
146 *
147 * DESCRIPTION: Search lower 1Mbyte of memory for the root system descriptor
148 * pointer structure. If it is found, set *RSDP to point to it.
149 *
150 * NOTE1: The RSDP must be either in the first 1K of the Extended
151 * BIOS Data Area or between E0000 and FFFFF (From ACPI Spec.)
152 * Only a 32-bit physical address is necessary.
153 *
154 * NOTE2: This function is always available, regardless of the
155 * initialization state of the rest of ACPI.
156 *
157 ******************************************************************************/
158
161 ACPI_PHYSICAL_ADDRESS *TableAddress)
162{
163 UINT8 *TablePtr;
164 UINT8 *MemRover;
166 UINT32 EbdaWindowSize;
167
168
170
171
172 /* 1a) Get the location of the Extended BIOS Data Area (EBDA) */
173
174 TablePtr = AcpiOsMapMemory (
175 (ACPI_PHYSICAL_ADDRESS) ACPI_EBDA_PTR_LOCATION,
177 if (!TablePtr)
178 {
180 "Could not map memory at 0x%8.8X for length %u",
182
184 }
185
187
188 /* Convert segment part to physical address */
189
190 PhysicalAddress <<= 4;
192
193 /* EBDA present? */
194
195 /*
196 * Check that the EBDA pointer from memory is sane and does not point
197 * above valid low memory
198 */
199 if (PhysicalAddress > 0x400 &&
200 PhysicalAddress < 0xA0000)
201 {
202 /*
203 * Calculate the scan window size
204 * The EBDA is not guaranteed to be larger than a KiB and in case
205 * that it is smaller, the scanning function would leave the low
206 * memory and continue to the VGA range.
207 */
208 EbdaWindowSize = ACPI_MIN(ACPI_EBDA_WINDOW_SIZE,
209 0xA0000 - PhysicalAddress);
210
211 /*
212 * 1b) Search EBDA paragraphs
213 */
214 TablePtr = AcpiOsMapMemory (
215 (ACPI_PHYSICAL_ADDRESS) PhysicalAddress,
216 EbdaWindowSize);
217 if (!TablePtr)
218 {
220 "Could not map memory at 0x%8.8X for length %u",
221 PhysicalAddress, EbdaWindowSize));
222
224 }
225
226 MemRover = AcpiTbScanMemoryForRsdp (
227 TablePtr, EbdaWindowSize);
228 AcpiOsUnmapMemory (TablePtr, EbdaWindowSize);
229
230 if (MemRover)
231 {
232 /* Return the physical address */
233
235 (UINT32) ACPI_PTR_DIFF (MemRover, TablePtr);
236
237 *TableAddress = (ACPI_PHYSICAL_ADDRESS) PhysicalAddress;
239 }
240 }
241
242 /*
243 * 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
244 */
245 TablePtr = AcpiOsMapMemory (
246 (ACPI_PHYSICAL_ADDRESS) ACPI_HI_RSDP_WINDOW_BASE,
248
249 if (!TablePtr)
250 {
252 "Could not map memory at 0x%8.8X for length %u",
254
256 }
257
258 MemRover = AcpiTbScanMemoryForRsdp (
259 TablePtr, ACPI_HI_RSDP_WINDOW_SIZE);
261
262 if (MemRover)
263 {
264 /* Return the physical address */
265
267 (ACPI_HI_RSDP_WINDOW_BASE + ACPI_PTR_DIFF (MemRover, TablePtr));
268
269 *TableAddress = (ACPI_PHYSICAL_ADDRESS) PhysicalAddress;
271 }
272
273 /* A valid RSDP was not found */
274
275 ACPI_BIOS_ERROR ((AE_INFO, "A valid RSDP was not found"));
277}
278
280
281
282/*******************************************************************************
283 *
284 * FUNCTION: AcpiTbScanMemoryForRsdp
285 *
286 * PARAMETERS: StartAddress - Starting pointer for search
287 * Length - Maximum length to search
288 *
289 * RETURN: Pointer to the RSDP if found, otherwise NULL.
290 *
291 * DESCRIPTION: Search a block of memory for the RSDP signature
292 *
293 ******************************************************************************/
294
295UINT8 *
297 UINT8 *StartAddress,
299{
301 UINT8 *MemRover;
302 UINT8 *EndAddress;
303
304
305 ACPI_FUNCTION_TRACE (TbScanMemoryForRsdp);
306
307
308 EndAddress = StartAddress + Length;
309
310 /* Search from given start address for the requested length */
311
312 for (MemRover = StartAddress; MemRover < EndAddress;
313 MemRover += ACPI_RSDP_SCAN_STEP)
314 {
315 /* The RSDP signature and checksum must both be correct */
316
318 ACPI_CAST_PTR (ACPI_TABLE_RSDP, MemRover));
319 if (ACPI_SUCCESS (Status))
320 {
321 /* Sig and checksum valid, we have found a real RSDP */
322
324 "RSDP located at physical address %p\n", MemRover));
325 return_PTR (MemRover);
326 }
327
328 /* No sig match or bad checksum, keep searching */
329 }
330
331 /* Searched entire block, no RSDP was found */
332
334 "Searched entire block from %p, valid RSDP was not found\n",
335 StartAddress));
337}
unsigned char UINT8
unsigned int UINT32
#define ACPI_INIT_FUNCTION
Definition: acenv.h:410
#define AE_BAD_CHECKSUM
Definition: acexcep.h:169
#define AE_BAD_SIGNATURE
Definition: acexcep.h:167
#define AE_NOT_FOUND
Definition: acexcep.h:113
#define AE_NO_MEMORY
Definition: acexcep.h:112
#define ACPI_SUCCESS(a)
Definition: acexcep.h:94
#define AE_OK
Definition: acexcep.h:97
#define ACPI_MOVE_16_TO_32(d, s)
Definition: acmacros.h:142
#define ACPI_DEBUG_PRINT(pl)
Definition: acoutput.h:475
#define ACPI_MODULE_NAME(Name)
Definition: acoutput.h:216
#define return_PTR(s)
Definition: acoutput.h:497
#define return_ACPI_STATUS(s)
Definition: acoutput.h:496
#define ACPI_FUNCTION_TRACE(a)
Definition: acoutput.h:480
#define ACPI_BIOS_ERROR(plist)
Definition: acoutput.h:243
#define ACPI_ERROR(plist)
Definition: acoutput.h:240
#define AE_INFO
Definition: acoutput.h:230
#define ACPI_DB_INFO
Definition: acoutput.h:153
void * AcpiOsMapMemory(ACPI_PHYSICAL_ADDRESS Where, ACPI_SIZE Length)
Definition: osl.c:108
void AcpiOsUnmapMemory(void *LogicalAddress, ACPI_SIZE Size)
Definition: osl.c:128
#define ACPI_VALIDATE_RSDP_SIG(a)
Definition: actypes.h:573
UINT32 ACPI_STATUS
Definition: actypes.h:460
#define ACPI_CAST_PTR(t, p)
Definition: actypes.h:544
#define ACPI_MIN(a, b)
Definition: actypes.h:535
#define ACPI_PTR_DIFF(a, b)
Definition: actypes.h:548
#define ACPI_EXPORT_SYMBOL_INIT(Symbol)
Definition: actypes.h:339
UINT8 AcpiUtChecksum(UINT8 *Buffer, UINT32 Length)
Definition: utcksum.c:213
#define NULL
Definition: types.h:112
#define ACPI_EBDA_PTR_LOCATION
Definition: acconfig.h:188
#define ACPI_RSDP_XCHECKSUM_LENGTH
Definition: acconfig.h:211
#define ACPI_RSDP_CHECKSUM_LENGTH
Definition: acconfig.h:210
#define ACPI_HI_RSDP_WINDOW_SIZE
Definition: acconfig.h:192
#define ACPI_HI_RSDP_WINDOW_BASE
Definition: acconfig.h:191
#define ACPI_EBDA_WINDOW_SIZE
Definition: acconfig.h:190
#define ACPI_EBDA_PTR_LENGTH
Definition: acconfig.h:189
#define ACPI_RSDP_SCAN_STEP
Definition: acconfig.h:193
Status
Definition: gdiplustypes.h:25
_In_ ULONG _In_ ULONG _In_ ULONG Length
Definition: ntddpcm.h:102
UINT8 Revision
Definition: actbl.h:154
char Signature[8]
Definition: actbl.h:151
ACPI_STATUS ACPI_INIT_FUNCTION AcpiFindRootPointer(ACPI_PHYSICAL_ADDRESS *TableAddress)
Definition: tbxfroot.c:160
ACPI_STATUS AcpiTbValidateRsdp(ACPI_TABLE_RSDP *Rsdp)
Definition: tbxfroot.c:103
UINT32 AcpiTbGetRsdpLength(ACPI_TABLE_RSDP *Rsdp)
Definition: tbxfroot.c:66
UINT8 * AcpiTbScanMemoryForRsdp(UINT8 *StartAddress, UINT32 Length)
Definition: tbxfroot.c:296
_Must_inspect_result_ typedef _In_ PHYSICAL_ADDRESS PhysicalAddress
Definition: iotypes.h:1098