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
13ACPI_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 ******************************************************************************/
29acpi_status
30acpi_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: aml_resource,
90 info: 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
133acpi_status
134acpi_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 info: 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}
236

source code of linux/drivers/acpi/acpica/rslist.c