1 /*
2 * APEI Hardware Error Souce Table support
3 *
4 * HEST describes error sources in detail; communicates operational
5 * parameters (i.e. severity levels, masking bits, and threshold
6 * values) to Linux as necessary. It also allows the BIOS to report
7 * non-standard error sources to Linux (for example, chipset-specific
8 * error registers).
9 *
10 * For more information about HEST, please refer to ACPI Specification
11 * version 4.0, section 17.3.2.
12 *
13 * Copyright 2009 Intel Corp.
14 * Author: Huang Ying <ying.huang@intel.com>
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License version
18 * 2 as published by the Free Software Foundation;
19 *
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
24 *
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
28 */
29
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/init.h>
33 #include <linux/acpi.h>
34 #include <linux/kdebug.h>
35 #include <linux/highmem.h>
36 #include <linux/io.h>
37 #include <linux/platform_device.h>
38 #include <acpi/apei.h>
39
40 #include "apei-internal.h"
41
42 #define HEST_PFX "HEST: "
43
44 bool hest_disable;
45 EXPORT_SYMBOL_GPL(hest_disable);
46
47 /* HEST table parsing */
48
49 static struct acpi_table_hest *__read_mostly hest_tab;
50
51 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
52 [ACPI_HEST_TYPE_IA32_CHECK] = -1, /* need further calculation */
53 [ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
54 [ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
55 [ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
56 [ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
57 [ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
58 [ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
59 };
60
hest_esrc_len(struct acpi_hest_header * hest_hdr)61 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
62 {
63 u16 hest_type = hest_hdr->type;
64 int len;
65
66 if (hest_type >= ACPI_HEST_TYPE_RESERVED)
67 return 0;
68
69 len = hest_esrc_len_tab[hest_type];
70
71 if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
72 struct acpi_hest_ia_corrected *cmc;
73 cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
74 len = sizeof(*cmc) + cmc->num_hardware_banks *
75 sizeof(struct acpi_hest_ia_error_bank);
76 } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
77 struct acpi_hest_ia_machine_check *mc;
78 mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
79 len = sizeof(*mc) + mc->num_hardware_banks *
80 sizeof(struct acpi_hest_ia_error_bank);
81 }
82 BUG_ON(len == -1);
83
84 return len;
85 };
86
apei_hest_parse(apei_hest_func_t func,void * data)87 int apei_hest_parse(apei_hest_func_t func, void *data)
88 {
89 struct acpi_hest_header *hest_hdr;
90 int i, rc, len;
91
92 if (hest_disable)
93 return -EINVAL;
94
95 hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
96 for (i = 0; i < hest_tab->error_source_count; i++) {
97 len = hest_esrc_len(hest_hdr);
98 if (!len) {
99 pr_warning(FW_WARN HEST_PFX
100 "Unknown or unused hardware error source "
101 "type: %d for hardware error source: %d.\n",
102 hest_hdr->type, hest_hdr->source_id);
103 return -EINVAL;
104 }
105 if ((void *)hest_hdr + len >
106 (void *)hest_tab + hest_tab->header.length) {
107 pr_warning(FW_BUG HEST_PFX
108 "Table contents overflow for hardware error source: %d.\n",
109 hest_hdr->source_id);
110 return -EINVAL;
111 }
112
113 rc = func(hest_hdr, data);
114 if (rc)
115 return rc;
116
117 hest_hdr = (void *)hest_hdr + len;
118 }
119
120 return 0;
121 }
122 EXPORT_SYMBOL_GPL(apei_hest_parse);
123
124 struct ghes_arr {
125 struct platform_device **ghes_devs;
126 unsigned int count;
127 };
128
hest_parse_ghes_count(struct acpi_hest_header * hest_hdr,void * data)129 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
130 {
131 int *count = data;
132
133 if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR)
134 (*count)++;
135 return 0;
136 }
137
hest_parse_ghes(struct acpi_hest_header * hest_hdr,void * data)138 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
139 {
140 struct platform_device *ghes_dev;
141 struct ghes_arr *ghes_arr = data;
142 int rc, i;
143
144 if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
145 return 0;
146
147 if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
148 return 0;
149 for (i = 0; i < ghes_arr->count; i++) {
150 struct acpi_hest_header *hdr;
151 ghes_dev = ghes_arr->ghes_devs[i];
152 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
153 if (hdr->source_id == hest_hdr->source_id) {
154 pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
155 hdr->source_id);
156 return -EIO;
157 }
158 }
159 ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
160 if (!ghes_dev)
161 return -ENOMEM;
162
163 rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
164 if (rc)
165 goto err;
166
167 rc = platform_device_add(ghes_dev);
168 if (rc)
169 goto err;
170 ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
171
172 return 0;
173 err:
174 platform_device_put(ghes_dev);
175 return rc;
176 }
177
hest_ghes_dev_register(unsigned int ghes_count)178 static int __init hest_ghes_dev_register(unsigned int ghes_count)
179 {
180 int rc, i;
181 struct ghes_arr ghes_arr;
182
183 ghes_arr.count = 0;
184 ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL);
185 if (!ghes_arr.ghes_devs)
186 return -ENOMEM;
187
188 rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
189 if (rc)
190 goto err;
191 out:
192 kfree(ghes_arr.ghes_devs);
193 return rc;
194 err:
195 for (i = 0; i < ghes_arr.count; i++)
196 platform_device_unregister(ghes_arr.ghes_devs[i]);
197 goto out;
198 }
199
setup_hest_disable(char * str)200 static int __init setup_hest_disable(char *str)
201 {
202 hest_disable = 1;
203 return 0;
204 }
205
206 __setup("hest_disable", setup_hest_disable);
207
acpi_hest_init(void)208 void __init acpi_hest_init(void)
209 {
210 acpi_status status;
211 int rc = -ENODEV;
212 unsigned int ghes_count = 0;
213
214 if (hest_disable) {
215 pr_info(HEST_PFX "Table parsing disabled.\n");
216 return;
217 }
218
219 if (acpi_disabled)
220 goto err;
221
222 status = acpi_get_table(ACPI_SIG_HEST, 0,
223 (struct acpi_table_header **)&hest_tab);
224 if (status == AE_NOT_FOUND)
225 goto err;
226 else if (ACPI_FAILURE(status)) {
227 const char *msg = acpi_format_exception(status);
228 pr_err(HEST_PFX "Failed to get table, %s\n", msg);
229 rc = -EINVAL;
230 goto err;
231 }
232
233 if (!ghes_disable) {
234 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
235 if (rc)
236 goto err;
237 rc = hest_ghes_dev_register(ghes_count);
238 if (rc)
239 goto err;
240 }
241
242 pr_info(HEST_PFX "Table parsing has been initialized.\n");
243 return;
244 err:
245 hest_disable = 1;
246 }
247