git.oblomov.eu Git - linux-2.6/blob - drivers/acpi/resources/rslist.c

   1 /*******************************************************************************
   2  *
   3  * Module Name: rslist - Linked list utilities
   4  *
   5  ******************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2005, R. Byron Moore
   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 #include <acpi/acpi.h>
  45 #include <acpi/acresrc.h>
  46
  47 #define _COMPONENT          ACPI_RESOURCES
  48 ACPI_MODULE_NAME("rslist")
  49
  50 /* Local prototypes */
  51 static struct acpi_rsconvert_info *acpi_rs_get_conversion_info(u8
  52                                                                resource_type);
  53
  54 static acpi_status acpi_rs_validate_resource_length(union aml_resource *aml);
  55
  56 /*******************************************************************************
  57  *
  58  * FUNCTION:    acpi_rs_validate_resource_length
  59  *
  60  * PARAMETERS:  Aml                 - Pointer to the AML resource descriptor
  61  *
  62  * RETURN:      Status - AE_OK if the resource length appears valid
  63  *
  64  * DESCRIPTION: Validate the resource_length. Fixed-length descriptors must
  65  *              have the exact length; variable-length descriptors must be
  66  *              at least as long as the minimum. Certain Small descriptors
  67  *              can vary in size by at most one byte.
  68  *
  69  ******************************************************************************/
  70
  71 static acpi_status acpi_rs_validate_resource_length(union aml_resource *aml)
  72 {
  73         struct acpi_resource_info *resource_info;
  74         u16 minimum_aml_resource_length;
  75         u16 resource_length;
  76
  77         ACPI_FUNCTION_ENTRY();
  78
  79         /* Get the size and type info about this resource descriptor */
  80
  81         resource_info =
  82             acpi_rs_get_resource_info(aml->small_header.descriptor_type);
  83         if (!resource_info) {
  84                 return (AE_AML_INVALID_RESOURCE_TYPE);
  85         }
  86
  87         resource_length = acpi_ut_get_resource_length(aml);
  88         minimum_aml_resource_length =
  89             resource_info->minimum_aml_resource_length;
  90
  91         /* Validate based upon the type of resource, fixed length or variable */
  92
  93         if (resource_info->length_type == ACPI_FIXED_LENGTH) {
  94                 /* Fixed length resource, length must match exactly */
  95
  96                 if (resource_length != minimum_aml_resource_length) {
  97                         return (AE_AML_BAD_RESOURCE_LENGTH);
  98                 }
  99         } else if (resource_info->length_type == ACPI_VARIABLE_LENGTH) {
 100                 /* Variable length resource, must be at least the minimum */
 101
 102                 if (resource_length < minimum_aml_resource_length) {
 103                         return (AE_AML_BAD_RESOURCE_LENGTH);
 104                 }
 105         } else {
 106                 /* Small variable length resource, allowed to be (Min) or (Min-1) */
 107
 108                 if ((resource_length > minimum_aml_resource_length) ||
 109                     (resource_length < (minimum_aml_resource_length - 1))) {
 110                         return (AE_AML_BAD_RESOURCE_LENGTH);
 111                 }
 112         }
 113
 114         return (AE_OK);
 115 }
 116
 117 /*******************************************************************************
 118  *
 119  * FUNCTION:    acpi_rs_get_conversion_info
 120  *
 121  * PARAMETERS:  resource_type       - Byte 0 of a resource descriptor
 122  *
 123  * RETURN:      Pointer to the resource conversion info table
 124  *
 125  * DESCRIPTION: Get the conversion table associated with this resource type
 126  *
 127  ******************************************************************************/
 128
 129 static struct acpi_rsconvert_info *acpi_rs_get_conversion_info(u8 resource_type)
 130 {
 131         ACPI_FUNCTION_ENTRY();
 132
 133         /* Determine if this is a small or large resource */
 134
 135         if (resource_type & ACPI_RESOURCE_NAME_LARGE) {
 136                 /* Large Resource Type -- bits 6:0 contain the name */
 137
 138                 if (resource_type > ACPI_RESOURCE_NAME_LARGE_MAX) {
 139                         return (NULL);
 140                 }
 141
 142                 return (acpi_gbl_lg_get_resource_dispatch[(resource_type &
 143                                                            ACPI_RESOURCE_NAME_LARGE_MASK)]);
 144         } else {
 145                 /* Small Resource Type -- bits 6:3 contain the name */
 146
 147                 return (acpi_gbl_sm_get_resource_dispatch[((resource_type &
 148                                                             ACPI_RESOURCE_NAME_SMALL_MASK)
 149                                                            >> 3)]);
 150         }
 151 }
 152
 153 /*******************************************************************************
 154  *
 155  * FUNCTION:    acpi_rs_convert_aml_to_resources
 156  *
 157  * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
 158  *              aml_buffer_length   - Length of aml_buffer
 159  *              output_buffer       - Pointer to the buffer that will
 160  *                                    contain the output structures
 161  *
 162  * RETURN:      Status
 163  *
 164  * DESCRIPTION: Takes the resource byte stream and parses it, creating a
 165  *              linked list of resources in the caller's output buffer
 166  *
 167  ******************************************************************************/
 168
 169 acpi_status
 170 acpi_rs_convert_aml_to_resources(u8 * aml_buffer,
 171                                  u32 aml_buffer_length, u8 * output_buffer)
 172 {
 173         u8 *buffer = output_buffer;
 174         acpi_status status;
 175         acpi_size bytes_parsed = 0;
 176         struct acpi_resource *resource;
 177         acpi_rsdesc_size descriptor_length;
 178         struct acpi_rsconvert_info *info;
 179
 180         ACPI_FUNCTION_TRACE("rs_convert_aml_to_resources");
 181
 182         /* Loop until end-of-buffer or an end_tag is found */
 183
 184         while (bytes_parsed < aml_buffer_length) {
 185                 /* Get the conversion table associated with this Descriptor Type */
 186
 187                 info = acpi_rs_get_conversion_info(*aml_buffer);
 188                 if (!info) {
 189                         /* No table indicates an invalid resource type */
 190
 191                         return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
 192                 }
 193
 194                 descriptor_length = acpi_ut_get_descriptor_length(aml_buffer);
 195
 196                 /*
 197                  * Perform limited validation of the resource length, based upon
 198                  * what we know about the resource type
 199                  */
 200                 status =
 201                     acpi_rs_validate_resource_length(ACPI_CAST_PTR
 202                                                      (union aml_resource,
 203                                                       aml_buffer));
 204                 if (ACPI_FAILURE(status)) {
 205                         return_ACPI_STATUS(status);
 206                 }
 207
 208                 /* Convert the AML byte stream resource to a local resource struct */
 209
 210                 status =
 211                     acpi_rs_convert_aml_to_resource(ACPI_CAST_PTR
 212                                                     (struct acpi_resource,
 213                                                      buffer),
 214                                                     ACPI_CAST_PTR(union
 215                                                                   aml_resource,
 216                                                                   aml_buffer),
 217                                                     info);
 218                 if (ACPI_FAILURE(status)) {
 219                         ACPI_REPORT_ERROR(("Could not convert AML resource (type %X) to resource, %s\n", *aml_buffer, acpi_format_exception(status)));
 220                         return_ACPI_STATUS(status);
 221                 }
 222
 223                 /* Set the aligned length of the new resource descriptor */
 224
 225                 resource = ACPI_CAST_PTR(struct acpi_resource, buffer);
 226                 resource->length =
 227                     (u32) ACPI_ALIGN_RESOURCE_SIZE(resource->length);
 228
 229                 /* Normal exit on completion of an end_tag resource descriptor */
 230
 231                 if (acpi_ut_get_resource_type(aml_buffer) ==
 232                     ACPI_RESOURCE_NAME_END_TAG) {
 233                         return_ACPI_STATUS(AE_OK);
 234                 }
 235
 236                 /* Update counter and point to the next input resource */
 237
 238                 bytes_parsed += descriptor_length;
 239                 aml_buffer += descriptor_length;
 240
 241                 /* Point to the next structure in the output buffer */
 242
 243                 buffer += resource->length;
 244         }
 245
 246         /* Completed buffer, but did not find an end_tag resource descriptor */
 247
 248         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 249 }
 250
 251 /*******************************************************************************
 252  *
 253  * FUNCTION:    acpi_rs_convert_resources_to_aml
 254  *
 255  * PARAMETERS:  Resource            - Pointer to the resource linked list
 256  *              aml_size_needed     - Calculated size of the byte stream
 257  *                                    needed from calling acpi_rs_get_aml_length()
 258  *                                    The size of the output_buffer is
 259  *                                    guaranteed to be >= aml_size_needed
 260  *              output_buffer       - Pointer to the buffer that will
 261  *                                    contain the byte stream
 262  *
 263  * RETURN:      Status
 264  *
 265  * DESCRIPTION: Takes the resource linked list and parses it, creating a
 266  *              byte stream of resources in the caller's output buffer
 267  *
 268  ******************************************************************************/
 269
 270 acpi_status
 271 acpi_rs_convert_resources_to_aml(struct acpi_resource *resource,
 272                                  acpi_size aml_size_needed, u8 * output_buffer)
 273 {
 274         u8 *aml_buffer = output_buffer;
 275         u8 *end_aml_buffer = output_buffer + aml_size_needed;
 276         acpi_status status;
 277
 278         ACPI_FUNCTION_TRACE("rs_convert_resources_to_aml");
 279
 280         /* Walk the resource descriptor list, convert each descriptor */
 281
 282         while (aml_buffer < end_aml_buffer) {
 283                 /* Validate the Resource Type */
 284
 285                 if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
 286                         ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
 287                                           "Invalid descriptor type (%X) in resource list\n",
 288                                           resource->type));
 289                         return_ACPI_STATUS(AE_BAD_DATA);
 290                 }
 291
 292                 /* Perform the conversion */
 293
 294                 status = acpi_rs_convert_resource_to_aml(resource,
 295                                                          ACPI_CAST_PTR(union
 296                                                                        aml_resource,
 297                                                                        aml_buffer),
 298                                                          acpi_gbl_set_resource_dispatch
 299                                                          [resource->type]);
 300                 if (ACPI_FAILURE(status)) {
 301                         ACPI_REPORT_ERROR(("Could not convert resource (type %X) to AML, %s\n", resource->type, acpi_format_exception(status)));
 302                         return_ACPI_STATUS(status);
 303                 }
 304
 305                 /* Perform final sanity check on the new AML resource descriptor */
 306
 307                 status =
 308                     acpi_rs_validate_resource_length(ACPI_CAST_PTR
 309                                                      (union aml_resource,
 310                                                       aml_buffer));
 311                 if (ACPI_FAILURE(status)) {
 312                         return_ACPI_STATUS(status);
 313                 }
 314
 315                 /* Check for end-of-list, normal exit */
 316
 317                 if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {
 318                         /* An End Tag indicates the end of the input Resource Template */
 319
 320                         return_ACPI_STATUS(AE_OK);
 321                 }
 322
 323                 /*
 324                  * Extract the total length of the new descriptor and set the
 325                  * aml_buffer to point to the next (output) resource descriptor
 326                  */
 327                 aml_buffer += acpi_ut_get_descriptor_length(aml_buffer);
 328
 329                 /* Point to the next input resource descriptor */
 330
 331                 resource =
 332                     ACPI_PTR_ADD(struct acpi_resource, resource,
 333                                  resource->length);
 334
 335                 /* Check for end-of-list, normal exit */
 336
 337         }
 338
 339         /* Completed buffer, but did not find an end_tag resource descriptor */
 340
 341         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 342 }