1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * APEI Hardware Error Source Table support
4 *
5 * HEST describes error sources in detail; communicates operational
6 * parameters (i.e. severity levels, masking bits, and threshold
7 * values) to Linux as necessary. It also allows the BIOS to report
8 * non-standard error sources to Linux (for example, chipset-specific
9 * error registers).
10 *
11 * For more information about HEST, please refer to ACPI Specification
12 * version 4.0, section 17.3.2.
13 *
14 * Copyright 2009 Intel Corp.
15 * Author: Huang Ying <ying.huang@intel.com>
16 */
17
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/acpi.h>
22 #include <linux/kdebug.h>
23 #include <linux/highmem.h>
24 #include <linux/io.h>
25 #include <linux/platform_device.h>
26 #include <acpi/apei.h>
27 #include <acpi/ghes.h>
28
29 #include "apei-internal.h"
30
31 #define HEST_PFX "HEST: "
32
33 int hest_disable;
34 EXPORT_SYMBOL_GPL(hest_disable);
35
36 /* HEST table parsing */
37
38 static struct acpi_table_hest *__read_mostly hest_tab;
39
40 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
41 [ACPI_HEST_TYPE_IA32_CHECK] = -1, /* need further calculation */
42 [ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
43 [ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
44 [ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
45 [ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
46 [ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
47 [ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
48 [ACPI_HEST_TYPE_GENERIC_ERROR_V2] = sizeof(struct acpi_hest_generic_v2),
49 [ACPI_HEST_TYPE_IA32_DEFERRED_CHECK] = -1,
50 };
51
is_generic_error(struct acpi_hest_header * hest_hdr)52 static inline bool is_generic_error(struct acpi_hest_header *hest_hdr)
53 {
54 return hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR ||
55 hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR_V2;
56 }
57
hest_esrc_len(struct acpi_hest_header * hest_hdr)58 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
59 {
60 u16 hest_type = hest_hdr->type;
61 int len;
62
63 if (hest_type >= ACPI_HEST_TYPE_RESERVED)
64 return 0;
65
66 len = hest_esrc_len_tab[hest_type];
67
68 if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
69 struct acpi_hest_ia_corrected *cmc;
70 cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
71 len = sizeof(*cmc) + cmc->num_hardware_banks *
72 sizeof(struct acpi_hest_ia_error_bank);
73 } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
74 struct acpi_hest_ia_machine_check *mc;
75 mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
76 len = sizeof(*mc) + mc->num_hardware_banks *
77 sizeof(struct acpi_hest_ia_error_bank);
78 } else if (hest_type == ACPI_HEST_TYPE_IA32_DEFERRED_CHECK) {
79 struct acpi_hest_ia_deferred_check *mc;
80 mc = (struct acpi_hest_ia_deferred_check *)hest_hdr;
81 len = sizeof(*mc) + mc->num_hardware_banks *
82 sizeof(struct acpi_hest_ia_error_bank);
83 }
84 BUG_ON(len == -1);
85
86 return len;
87 };
88
apei_hest_parse(apei_hest_func_t func,void * data)89 int apei_hest_parse(apei_hest_func_t func, void *data)
90 {
91 struct acpi_hest_header *hest_hdr;
92 int i, rc, len;
93
94 if (hest_disable || !hest_tab)
95 return -EINVAL;
96
97 hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
98 for (i = 0; i < hest_tab->error_source_count; i++) {
99 len = hest_esrc_len(hest_hdr);
100 if (!len) {
101 pr_warn(FW_WARN HEST_PFX
102 "Unknown or unused hardware error source "
103 "type: %d for hardware error source: %d.\n",
104 hest_hdr->type, hest_hdr->source_id);
105 return -EINVAL;
106 }
107 if ((void *)hest_hdr + len >
108 (void *)hest_tab + hest_tab->header.length) {
109 pr_warn(FW_BUG HEST_PFX
110 "Table contents overflow for hardware error source: %d.\n",
111 hest_hdr->source_id);
112 return -EINVAL;
113 }
114
115 rc = func(hest_hdr, data);
116 if (rc)
117 return rc;
118
119 hest_hdr = (void *)hest_hdr + len;
120 }
121
122 return 0;
123 }
124 EXPORT_SYMBOL_GPL(apei_hest_parse);
125
126 /*
127 * Check if firmware advertises firmware first mode. We need FF bit to be set
128 * along with a set of MC banks which work in FF mode.
129 */
hest_parse_cmc(struct acpi_hest_header * hest_hdr,void * data)130 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
131 {
132 if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
133 return 0;
134
135 if (!acpi_disable_cmcff)
136 return !arch_apei_enable_cmcff(hest_hdr, data);
137
138 return 0;
139 }
140
141 struct ghes_arr {
142 struct platform_device **ghes_devs;
143 unsigned int count;
144 };
145
hest_parse_ghes_count(struct acpi_hest_header * hest_hdr,void * data)146 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
147 {
148 int *count = data;
149
150 if (is_generic_error(hest_hdr))
151 (*count)++;
152 return 0;
153 }
154
hest_parse_ghes(struct acpi_hest_header * hest_hdr,void * data)155 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
156 {
157 struct platform_device *ghes_dev;
158 struct ghes_arr *ghes_arr = data;
159 int rc, i;
160
161 if (!is_generic_error(hest_hdr))
162 return 0;
163
164 if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
165 return 0;
166 for (i = 0; i < ghes_arr->count; i++) {
167 struct acpi_hest_header *hdr;
168 ghes_dev = ghes_arr->ghes_devs[i];
169 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
170 if (hdr->source_id == hest_hdr->source_id) {
171 pr_warn(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
172 hdr->source_id);
173 return -EIO;
174 }
175 }
176 ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
177 if (!ghes_dev)
178 return -ENOMEM;
179
180 rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
181 if (rc)
182 goto err;
183
184 rc = platform_device_add(ghes_dev);
185 if (rc)
186 goto err;
187 ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
188
189 return 0;
190 err:
191 platform_device_put(ghes_dev);
192 return rc;
193 }
194
hest_ghes_dev_register(unsigned int ghes_count)195 static int __init hest_ghes_dev_register(unsigned int ghes_count)
196 {
197 int rc, i;
198 struct ghes_arr ghes_arr;
199
200 ghes_arr.count = 0;
201 ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *),
202 GFP_KERNEL);
203 if (!ghes_arr.ghes_devs)
204 return -ENOMEM;
205
206 rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
207 if (rc)
208 goto err;
209
210 rc = ghes_estatus_pool_init(ghes_count);
211 if (rc)
212 goto err;
213
214 out:
215 kfree(ghes_arr.ghes_devs);
216 return rc;
217 err:
218 for (i = 0; i < ghes_arr.count; i++)
219 platform_device_unregister(ghes_arr.ghes_devs[i]);
220 goto out;
221 }
222
setup_hest_disable(char * str)223 static int __init setup_hest_disable(char *str)
224 {
225 hest_disable = HEST_DISABLED;
226 return 1;
227 }
228
229 __setup("hest_disable", setup_hest_disable);
230
acpi_hest_init(void)231 void __init acpi_hest_init(void)
232 {
233 acpi_status status;
234 int rc;
235 unsigned int ghes_count = 0;
236
237 if (hest_disable) {
238 pr_info(HEST_PFX "Table parsing disabled.\n");
239 return;
240 }
241
242 status = acpi_get_table(ACPI_SIG_HEST, 0,
243 (struct acpi_table_header **)&hest_tab);
244 if (status == AE_NOT_FOUND) {
245 hest_disable = HEST_NOT_FOUND;
246 return;
247 } else if (ACPI_FAILURE(status)) {
248 const char *msg = acpi_format_exception(status);
249 pr_err(HEST_PFX "Failed to get table, %s\n", msg);
250 hest_disable = HEST_DISABLED;
251 return;
252 }
253
254 rc = apei_hest_parse(hest_parse_cmc, NULL);
255 if (rc)
256 goto err;
257
258 if (!ghes_disable) {
259 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
260 if (rc)
261 goto err;
262
263 if (ghes_count)
264 rc = hest_ghes_dev_register(ghes_count);
265 if (rc)
266 goto err;
267 }
268
269 pr_info(HEST_PFX "Table parsing has been initialized.\n");
270 return;
271 err:
272 hest_disable = HEST_DISABLED;
273 acpi_put_table((struct acpi_table_header *)hest_tab);
274 }
275