xref: /openbmc/linux/drivers/acpi/acpica/tbprint.c (revision 5d331b7f)
1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
2 /******************************************************************************
3  *
4  * Module Name: tbprint - Table output utilities
5  *
6  * Copyright (C) 2000 - 2018, Intel Corp.
7  *
8  *****************************************************************************/
9 
10 #include <acpi/acpi.h>
11 #include "accommon.h"
12 #include "actables.h"
13 
14 #define _COMPONENT          ACPI_TABLES
15 ACPI_MODULE_NAME("tbprint")
16 
17 /* Local prototypes */
18 static void acpi_tb_fix_string(char *string, acpi_size length);
19 
20 static void
21 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header,
22 			     struct acpi_table_header *header);
23 
24 /*******************************************************************************
25  *
26  * FUNCTION:    acpi_tb_fix_string
27  *
28  * PARAMETERS:  string              - String to be repaired
29  *              length              - Maximum length
30  *
31  * RETURN:      None
32  *
33  * DESCRIPTION: Replace every non-printable or non-ascii byte in the string
34  *              with a question mark '?'.
35  *
36  ******************************************************************************/
37 
38 static void acpi_tb_fix_string(char *string, acpi_size length)
39 {
40 
41 	while (length && *string) {
42 		if (!isprint((int)*string)) {
43 			*string = '?';
44 		}
45 
46 		string++;
47 		length--;
48 	}
49 }
50 
51 /*******************************************************************************
52  *
53  * FUNCTION:    acpi_tb_cleanup_table_header
54  *
55  * PARAMETERS:  out_header          - Where the cleaned header is returned
56  *              header              - Input ACPI table header
57  *
58  * RETURN:      Returns the cleaned header in out_header
59  *
60  * DESCRIPTION: Copy the table header and ensure that all "string" fields in
61  *              the header consist of printable characters.
62  *
63  ******************************************************************************/
64 
65 static void
66 acpi_tb_cleanup_table_header(struct acpi_table_header *out_header,
67 			     struct acpi_table_header *header)
68 {
69 
70 	memcpy(out_header, header, sizeof(struct acpi_table_header));
71 
72 	acpi_tb_fix_string(out_header->signature, ACPI_NAME_SIZE);
73 	acpi_tb_fix_string(out_header->oem_id, ACPI_OEM_ID_SIZE);
74 	acpi_tb_fix_string(out_header->oem_table_id, ACPI_OEM_TABLE_ID_SIZE);
75 	acpi_tb_fix_string(out_header->asl_compiler_id, ACPI_NAME_SIZE);
76 }
77 
78 /*******************************************************************************
79  *
80  * FUNCTION:    acpi_tb_print_table_header
81  *
82  * PARAMETERS:  address             - Table physical address
83  *              header              - Table header
84  *
85  * RETURN:      None
86  *
87  * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
88  *
89  ******************************************************************************/
90 
91 void
92 acpi_tb_print_table_header(acpi_physical_address address,
93 			   struct acpi_table_header *header)
94 {
95 	struct acpi_table_header local_header;
96 
97 	if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
98 
99 		/* FACS only has signature and length fields */
100 
101 		ACPI_INFO(("%-4.4s 0x%8.8X%8.8X %06X",
102 			   header->signature, ACPI_FORMAT_UINT64(address),
103 			   header->length));
104 	} else if (ACPI_VALIDATE_RSDP_SIG(header->signature)) {
105 
106 		/* RSDP has no common fields */
107 
108 		memcpy(local_header.oem_id,
109 		       ACPI_CAST_PTR(struct acpi_table_rsdp, header)->oem_id,
110 		       ACPI_OEM_ID_SIZE);
111 		acpi_tb_fix_string(local_header.oem_id, ACPI_OEM_ID_SIZE);
112 
113 		ACPI_INFO(("RSDP 0x%8.8X%8.8X %06X (v%.2d %-6.6s)",
114 			   ACPI_FORMAT_UINT64(address),
115 			   (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
116 			    revision >
117 			    0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
118 					       header)->length : 20,
119 			   ACPI_CAST_PTR(struct acpi_table_rsdp,
120 					 header)->revision,
121 			   local_header.oem_id));
122 	} else {
123 		/* Standard ACPI table with full common header */
124 
125 		acpi_tb_cleanup_table_header(&local_header, header);
126 
127 		ACPI_INFO(("%-4.4s 0x%8.8X%8.8X"
128 			   " %06X (v%.2d %-6.6s %-8.8s %08X %-4.4s %08X)",
129 			   local_header.signature, ACPI_FORMAT_UINT64(address),
130 			   local_header.length, local_header.revision,
131 			   local_header.oem_id, local_header.oem_table_id,
132 			   local_header.oem_revision,
133 			   local_header.asl_compiler_id,
134 			   local_header.asl_compiler_revision));
135 	}
136 }
137 
138 /*******************************************************************************
139  *
140  * FUNCTION:    acpi_tb_validate_checksum
141  *
142  * PARAMETERS:  table               - ACPI table to verify
143  *              length              - Length of entire table
144  *
145  * RETURN:      Status
146  *
147  * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
148  *              exception on bad checksum.
149  *
150  ******************************************************************************/
151 
152 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
153 {
154 	u8 checksum;
155 
156 	/*
157 	 * FACS/S3PT:
158 	 * They are the odd tables, have no standard ACPI header and no checksum
159 	 */
160 
161 	if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_S3PT) ||
162 	    ACPI_COMPARE_NAME(table->signature, ACPI_SIG_FACS)) {
163 		return (AE_OK);
164 	}
165 
166 	/* Compute the checksum on the table */
167 
168 	checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
169 
170 	/* Checksum ok? (should be zero) */
171 
172 	if (checksum) {
173 		ACPI_BIOS_WARNING((AE_INFO,
174 				   "Incorrect checksum in table [%4.4s] - 0x%2.2X, "
175 				   "should be 0x%2.2X",
176 				   table->signature, table->checksum,
177 				   (u8)(table->checksum - checksum)));
178 
179 #if (ACPI_CHECKSUM_ABORT)
180 		return (AE_BAD_CHECKSUM);
181 #endif
182 	}
183 
184 	return (AE_OK);
185 }
186 
187 /*******************************************************************************
188  *
189  * FUNCTION:    acpi_tb_checksum
190  *
191  * PARAMETERS:  buffer          - Pointer to memory region to be checked
192  *              length          - Length of this memory region
193  *
194  * RETURN:      Checksum (u8)
195  *
196  * DESCRIPTION: Calculates circular checksum of memory region.
197  *
198  ******************************************************************************/
199 
200 u8 acpi_tb_checksum(u8 *buffer, u32 length)
201 {
202 	u8 sum = 0;
203 	u8 *end = buffer + length;
204 
205 	while (buffer < end) {
206 		sum = (u8)(sum + *(buffer++));
207 	}
208 
209 	return (sum);
210 }
211