ia64/xen-unstable

view xen/drivers/acpi/tables/tbxfroot.c @ 18896:f7f8f44b9292

tools: Fix a few error-path memory leaks.

Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Dec 09 12:53:19 2008 +0000 (2008-12-09)
parents ae29cd95ba7d
children
line source
1 /******************************************************************************
2 *
3 * Module Name: tbxfroot - Find the root ACPI table (RSDT)
4 *
5 *****************************************************************************/
7 /*
8 * Copyright (C) 2000 - 2008, 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 */
44 #include <xen/config.h>
45 #include <xen/init.h>
46 #include <acpi/acpi.h>
47 #include <acpi/actables.h>
49 #define _COMPONENT ACPI_TABLES
50 ACPI_MODULE_NAME("tbxfroot")
52 /* Local prototypes */
53 static u8 *acpi_tb_scan_memory_for_rsdp(u8 * start_address, u32 length);
55 static acpi_status acpi_tb_validate_rsdp(struct acpi_table_rsdp *rsdp);
57 /*******************************************************************************
58 *
59 * FUNCTION: acpi_tb_validate_rsdp
60 *
61 * PARAMETERS: Rsdp - Pointer to unvalidated RSDP
62 *
63 * RETURN: Status
64 *
65 * DESCRIPTION: Validate the RSDP (ptr)
66 *
67 ******************************************************************************/
69 static acpi_status acpi_tb_validate_rsdp(struct acpi_table_rsdp *rsdp)
70 {
71 ACPI_FUNCTION_ENTRY();
73 /*
74 * The signature and checksum must both be correct
75 *
76 * Note: Sometimes there exists more than one RSDP in memory; the valid
77 * RSDP has a valid checksum, all others have an invalid checksum.
78 */
79 if (ACPI_STRNCMP((char *)rsdp, ACPI_SIG_RSDP, sizeof(ACPI_SIG_RSDP) - 1)
80 != 0) {
82 /* Nope, BAD Signature */
84 return (AE_BAD_SIGNATURE);
85 }
87 /* Check the standard checksum */
89 if (acpi_tb_checksum((u8 *) rsdp, ACPI_RSDP_CHECKSUM_LENGTH) != 0) {
90 return (AE_BAD_CHECKSUM);
91 }
93 /* Check extended checksum if table version >= 2 */
95 if ((rsdp->revision >= 2) &&
96 (acpi_tb_checksum((u8 *) rsdp, ACPI_RSDP_XCHECKSUM_LENGTH) != 0)) {
97 return (AE_BAD_CHECKSUM);
98 }
100 return (AE_OK);
101 }
103 /*******************************************************************************
104 *
105 * FUNCTION: acpi_find_root_pointer
106 *
107 * PARAMETERS: table_address - Where the table pointer is returned
108 *
109 * RETURN: Status, RSDP physical address
110 *
111 * DESCRIPTION: Search lower 1_mbyte of memory for the root system descriptor
112 * pointer structure. If it is found, set *RSDP to point to it.
113 *
114 * NOTE1: The RSDP must be either in the first 1_k of the Extended
115 * BIOS Data Area or between E0000 and FFFFF (From ACPI Spec.)
116 * Only a 32-bit physical address is necessary.
117 *
118 * NOTE2: This function is always available, regardless of the
119 * initialization state of the rest of ACPI.
120 *
121 ******************************************************************************/
123 acpi_status __init acpi_find_root_pointer(acpi_native_uint * table_address)
124 {
125 u8 *table_ptr;
126 u8 *mem_rover;
127 u32 physical_address;
129 ACPI_FUNCTION_TRACE(acpi_find_root_pointer);
131 /* 1a) Get the location of the Extended BIOS Data Area (EBDA) */
133 table_ptr = acpi_os_map_memory((acpi_physical_address)
134 ACPI_EBDA_PTR_LOCATION,
135 ACPI_EBDA_PTR_LENGTH);
136 if (!table_ptr) {
137 ACPI_ERROR((AE_INFO,
138 "Could not map memory at %8.8X for length %X",
139 ACPI_EBDA_PTR_LOCATION, ACPI_EBDA_PTR_LENGTH));
141 return_ACPI_STATUS(AE_NO_MEMORY);
142 }
144 ACPI_MOVE_16_TO_32(&physical_address, table_ptr);
146 /* Convert segment part to physical address */
148 physical_address <<= 4;
149 acpi_os_unmap_memory(table_ptr, ACPI_EBDA_PTR_LENGTH);
151 /* EBDA present? */
153 if (physical_address > 0x400) {
154 /*
155 * 1b) Search EBDA paragraphs (EBDA is required to be a
156 * minimum of 1_k length)
157 */
158 table_ptr = acpi_os_map_memory((acpi_native_uint)
159 physical_address,
160 ACPI_EBDA_WINDOW_SIZE);
161 if (!table_ptr) {
162 ACPI_ERROR((AE_INFO,
163 "Could not map memory at %8.8X for length %X",
164 physical_address, ACPI_EBDA_WINDOW_SIZE));
166 return_ACPI_STATUS(AE_NO_MEMORY);
167 }
169 mem_rover =
170 acpi_tb_scan_memory_for_rsdp(table_ptr,
171 ACPI_EBDA_WINDOW_SIZE);
172 acpi_os_unmap_memory(table_ptr, ACPI_EBDA_WINDOW_SIZE);
174 if (mem_rover) {
176 /* Return the physical address */
178 physical_address +=
179 (u32) ACPI_PTR_DIFF(mem_rover, table_ptr);
181 *table_address = physical_address;
182 return_ACPI_STATUS(AE_OK);
183 }
184 }
186 /*
187 * 2) Search upper memory: 16-byte boundaries in E0000h-FFFFFh
188 */
189 table_ptr = acpi_os_map_memory((acpi_physical_address)
190 ACPI_HI_RSDP_WINDOW_BASE,
191 ACPI_HI_RSDP_WINDOW_SIZE);
193 if (!table_ptr) {
194 ACPI_ERROR((AE_INFO,
195 "Could not map memory at %8.8X for length %X",
196 ACPI_HI_RSDP_WINDOW_BASE,
197 ACPI_HI_RSDP_WINDOW_SIZE));
199 return_ACPI_STATUS(AE_NO_MEMORY);
200 }
202 mem_rover =
203 acpi_tb_scan_memory_for_rsdp(table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
204 acpi_os_unmap_memory(table_ptr, ACPI_HI_RSDP_WINDOW_SIZE);
206 if (mem_rover) {
208 /* Return the physical address */
210 physical_address = (u32)
211 (ACPI_HI_RSDP_WINDOW_BASE +
212 ACPI_PTR_DIFF(mem_rover, table_ptr));
214 *table_address = physical_address;
215 return_ACPI_STATUS(AE_OK);
216 }
218 /* A valid RSDP was not found */
220 ACPI_ERROR((AE_INFO, "A valid RSDP was not found"));
221 return_ACPI_STATUS(AE_NOT_FOUND);
222 }
224 /*******************************************************************************
225 *
226 * FUNCTION: acpi_tb_scan_memory_for_rsdp
227 *
228 * PARAMETERS: start_address - Starting pointer for search
229 * Length - Maximum length to search
230 *
231 * RETURN: Pointer to the RSDP if found, otherwise NULL.
232 *
233 * DESCRIPTION: Search a block of memory for the RSDP signature
234 *
235 ******************************************************************************/
236 static u8 *__init acpi_tb_scan_memory_for_rsdp(u8 * start_address, u32 length)
237 {
238 acpi_status status;
239 u8 *mem_rover;
240 u8 *end_address;
242 ACPI_FUNCTION_TRACE(tb_scan_memory_for_rsdp);
244 end_address = start_address + length;
246 /* Search from given start address for the requested length */
248 for (mem_rover = start_address; mem_rover < end_address;
249 mem_rover += ACPI_RSDP_SCAN_STEP) {
251 /* The RSDP signature and checksum must both be correct */
253 status =
254 acpi_tb_validate_rsdp(ACPI_CAST_PTR
255 (struct acpi_table_rsdp, mem_rover));
256 if (ACPI_SUCCESS(status)) {
258 /* Sig and checksum valid, we have found a real RSDP */
260 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
261 "RSDP located at physical address %p\n",
262 mem_rover));
263 return_PTR(mem_rover);
264 }
266 /* No sig match or bad checksum, keep searching */
267 }
269 /* Searched entire block, no RSDP was found */
271 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
272 "Searched entire block from %p, valid RSDP was not found\n",
273 start_address));
274 return_PTR(NULL);
275 }