acpica/rslist.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /*******************************************************************************
   3  *
   4  * Module Name: rslist - Linked list utilities
   5  *
   6  ******************************************************************************/
   7
   8 #include <acpi/acpi.h>
   9 #include "accommon.h"
  10 #include "acresrc.h"
  11
  12 #define _COMPONENT          ACPI_RESOURCES
  13 ACPI_MODULE_NAME("rslist")
  14
  15 /*******************************************************************************
  16  *
  17  * FUNCTION:    acpi_rs_convert_aml_to_resources
  18  *
  19  * PARAMETERS:  acpi_walk_aml_callback
  20  *              resource_ptr            - Pointer to the buffer that will
  21  *                                        contain the output structures
  22  *
  23  * RETURN:      Status
  24  *
  25  * DESCRIPTION: Convert an AML resource to an internal representation of the
  26  *              resource that is aligned and easier to access.
  27  *
  28  ******************************************************************************/
  29 acpi_status
  30 acpi_rs_convert_aml_to_resources(u8 * aml,
  31                                  u32 length,
  32                                  u32 offset, u8 resource_index, void **context)
  33 {
  34         struct acpi_resource **resource_ptr =
  35             ACPI_CAST_INDIRECT_PTR(struct acpi_resource, context);
  36         struct acpi_resource *resource;
  37         union aml_resource *aml_resource;
  38         struct acpi_rsconvert_info *conversion_table;
  39         acpi_status status;
  40
  41         ACPI_FUNCTION_TRACE(rs_convert_aml_to_resources);
  42
  43         /*
  44          * Check that the input buffer and all subsequent pointers into it
  45          * are aligned on a native word boundary. Most important on IA64
  46          */
  47         resource = *resource_ptr;
  48         if (ACPI_IS_MISALIGNED(resource)) {
  49                 ACPI_WARNING((AE_INFO,
  50                               "Misaligned resource pointer %p", resource));
  51         }
  52
  53         /* Get the appropriate conversion info table */
  54
  55         aml_resource = ACPI_CAST_PTR(union aml_resource, aml);
  56
  57         if (acpi_ut_get_resource_type(aml) == ACPI_RESOURCE_NAME_SERIAL_BUS) {
  58
  59                 /* Avoid undefined behavior: member access within misaligned address */
  60
  61                 struct aml_resource_common_serialbus common_serial_bus;
  62                 memcpy(&common_serial_bus, aml_resource,
  63                        sizeof(common_serial_bus));
  64
  65                 if (common_serial_bus.type > AML_RESOURCE_MAX_SERIALBUSTYPE) {
  66                         conversion_table = NULL;
  67                 } else {
  68                         /* This is an I2C, SPI, UART, or CSI2 serial_bus descriptor */
  69
  70                         conversion_table =
  71                             acpi_gbl_convert_resource_serial_bus_dispatch
  72                             [common_serial_bus.type];
  73                 }
  74         } else {
  75                 conversion_table =
  76                     acpi_gbl_get_resource_dispatch[resource_index];
  77         }
  78
  79         if (!conversion_table) {
  80                 ACPI_ERROR((AE_INFO,
  81                             "Invalid/unsupported resource descriptor: Type 0x%2.2X",
  82                             resource_index));
  83                 return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
  84         }
  85
  86         /* Convert the AML byte stream resource to a local resource struct */
  87
  88         status =
  89             acpi_rs_convert_aml_to_resource(resource, aml_resource,
  90                                             conversion_table);
  91         if (ACPI_FAILURE(status)) {
  92                 ACPI_EXCEPTION((AE_INFO, status,
  93                                 "Could not convert AML resource (Type 0x%X)",
  94                                 *aml));
  95                 return_ACPI_STATUS(status);
  96         }
  97
  98         if (!resource->length) {
  99                 ACPI_EXCEPTION((AE_INFO, status,
 100                                 "Zero-length resource returned from RsConvertAmlToResource"));
 101         }
 102
 103         ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
 104                           "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
 105                           acpi_ut_get_resource_type(aml), length,
 106                           resource->length));
 107
 108         /* Point to the next structure in the output buffer */
 109
 110         *resource_ptr = ACPI_NEXT_RESOURCE(resource);
 111         return_ACPI_STATUS(AE_OK);
 112 }
 113
 114 /*******************************************************************************
 115  *
 116  * FUNCTION:    acpi_rs_convert_resources_to_aml
 117  *
 118  * PARAMETERS:  resource            - Pointer to the resource linked list
 119  *              aml_size_needed     - Calculated size of the byte stream
 120  *                                    needed from calling acpi_rs_get_aml_length()
 121  *                                    The size of the output_buffer is
 122  *                                    guaranteed to be >= aml_size_needed
 123  *              output_buffer       - Pointer to the buffer that will
 124  *                                    contain the byte stream
 125  *
 126  * RETURN:      Status
 127  *
 128  * DESCRIPTION: Takes the resource linked list and parses it, creating a
 129  *              byte stream of resources in the caller's output buffer
 130  *
 131  ******************************************************************************/
 132
 133 acpi_status
 134 acpi_rs_convert_resources_to_aml(struct acpi_resource *resource,
 135                                  acpi_size aml_size_needed, u8 * output_buffer)
 136 {
 137         u8 *aml = output_buffer;
 138         u8 *end_aml = output_buffer + aml_size_needed;
 139         struct acpi_rsconvert_info *conversion_table;
 140         acpi_status status;
 141
 142         ACPI_FUNCTION_TRACE(rs_convert_resources_to_aml);
 143
 144         /* Walk the resource descriptor list, convert each descriptor */
 145
 146         while (aml < end_aml) {
 147
 148                 /* Validate the (internal) Resource Type */
 149
 150                 if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
 151                         ACPI_ERROR((AE_INFO,
 152                                     "Invalid descriptor type (0x%X) in resource list",
 153                                     resource->type));
 154                         return_ACPI_STATUS(AE_BAD_DATA);
 155                 }
 156
 157                 /* Sanity check the length. It must not be zero, or we loop forever */
 158
 159                 if (!resource->length) {
 160                         ACPI_ERROR((AE_INFO,
 161                                     "Invalid zero length descriptor in resource list\n"));
 162                         return_ACPI_STATUS(AE_AML_BAD_RESOURCE_LENGTH);
 163                 }
 164
 165                 /* Perform the conversion */
 166
 167                 if (resource->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
 168                         if (resource->data.common_serial_bus.type >
 169                             AML_RESOURCE_MAX_SERIALBUSTYPE) {
 170                                 conversion_table = NULL;
 171                         } else {
 172                                 /* This is an I2C, SPI, UART or CSI2 serial_bus descriptor */
 173
 174                                 conversion_table =
 175                                     acpi_gbl_convert_resource_serial_bus_dispatch
 176                                     [resource->data.common_serial_bus.type];
 177                         }
 178                 } else {
 179                         conversion_table =
 180                             acpi_gbl_set_resource_dispatch[resource->type];
 181                 }
 182
 183                 if (!conversion_table) {
 184                         ACPI_ERROR((AE_INFO,
 185                                     "Invalid/unsupported resource descriptor: Type 0x%2.2X",
 186                                     resource->type));
 187                         return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
 188                 }
 189
 190                 status = acpi_rs_convert_resource_to_aml(resource,
 191                                                          ACPI_CAST_PTR(union
 192                                                                        aml_resource,
 193                                                                        aml),
 194                                                          conversion_table);
 195                 if (ACPI_FAILURE(status)) {
 196                         ACPI_EXCEPTION((AE_INFO, status,
 197                                         "Could not convert resource (type 0x%X) to AML",
 198                                         resource->type));
 199                         return_ACPI_STATUS(status);
 200                 }
 201
 202                 /* Perform final sanity check on the new AML resource descriptor */
 203
 204                 status =
 205                     acpi_ut_validate_resource(NULL,
 206                                               ACPI_CAST_PTR(union aml_resource,
 207                                                             aml), NULL);
 208                 if (ACPI_FAILURE(status)) {
 209                         return_ACPI_STATUS(status);
 210                 }
 211
 212                 /* Check for end-of-list, normal exit */
 213
 214                 if (resource->type == ACPI_RESOURCE_TYPE_END_TAG) {
 215
 216                         /* An End Tag indicates the end of the input Resource Template */
 217
 218                         return_ACPI_STATUS(AE_OK);
 219                 }
 220
 221                 /*
 222                  * Extract the total length of the new descriptor and set the
 223                  * Aml to point to the next (output) resource descriptor
 224                  */
 225                 aml += acpi_ut_get_descriptor_length(aml);
 226
 227                 /* Point to the next input resource descriptor */
 228
 229                 resource = ACPI_NEXT_RESOURCE(resource);
 230         }
 231
 232         /* Completed buffer, but did not find an end_tag resource descriptor */
 233
 234         return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
 235 }