xref: /openbmc/linux/drivers/acpi/apei/hest.c (revision 367e5927)
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 
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/acpi.h>
30 #include <linux/kdebug.h>
31 #include <linux/highmem.h>
32 #include <linux/io.h>
33 #include <linux/platform_device.h>
34 #include <acpi/apei.h>
35 #include <acpi/ghes.h>
36 
37 #include "apei-internal.h"
38 
39 #define HEST_PFX "HEST: "
40 
41 int hest_disable;
42 EXPORT_SYMBOL_GPL(hest_disable);
43 
44 /* HEST table parsing */
45 
46 static struct acpi_table_hest *__read_mostly hest_tab;
47 
48 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
49 	[ACPI_HEST_TYPE_IA32_CHECK] = -1,	/* need further calculation */
50 	[ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
51 	[ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
52 	[ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
53 	[ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
54 	[ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
55 	[ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
56 	[ACPI_HEST_TYPE_GENERIC_ERROR_V2] = sizeof(struct acpi_hest_generic_v2),
57 	[ACPI_HEST_TYPE_IA32_DEFERRED_CHECK] = -1,
58 };
59 
60 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
61 {
62 	u16 hest_type = hest_hdr->type;
63 	int len;
64 
65 	if (hest_type >= ACPI_HEST_TYPE_RESERVED)
66 		return 0;
67 
68 	len = hest_esrc_len_tab[hest_type];
69 
70 	if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
71 		struct acpi_hest_ia_corrected *cmc;
72 		cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
73 		len = sizeof(*cmc) + cmc->num_hardware_banks *
74 			sizeof(struct acpi_hest_ia_error_bank);
75 	} else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
76 		struct acpi_hest_ia_machine_check *mc;
77 		mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
78 		len = sizeof(*mc) + mc->num_hardware_banks *
79 			sizeof(struct acpi_hest_ia_error_bank);
80 	} else if (hest_type == ACPI_HEST_TYPE_IA32_DEFERRED_CHECK) {
81 		struct acpi_hest_ia_deferred_check *mc;
82 		mc = (struct acpi_hest_ia_deferred_check *)hest_hdr;
83 		len = sizeof(*mc) + mc->num_hardware_banks *
84 			sizeof(struct acpi_hest_ia_error_bank);
85 	}
86 	BUG_ON(len == -1);
87 
88 	return len;
89 };
90 
91 int apei_hest_parse(apei_hest_func_t func, void *data)
92 {
93 	struct acpi_hest_header *hest_hdr;
94 	int i, rc, len;
95 
96 	if (hest_disable || !hest_tab)
97 		return -EINVAL;
98 
99 	hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
100 	for (i = 0; i < hest_tab->error_source_count; i++) {
101 		len = hest_esrc_len(hest_hdr);
102 		if (!len) {
103 			pr_warning(FW_WARN HEST_PFX
104 				   "Unknown or unused hardware error source "
105 				   "type: %d for hardware error source: %d.\n",
106 				   hest_hdr->type, hest_hdr->source_id);
107 			return -EINVAL;
108 		}
109 		if ((void *)hest_hdr + len >
110 		    (void *)hest_tab + hest_tab->header.length) {
111 			pr_warning(FW_BUG HEST_PFX
112 		"Table contents overflow for hardware error source: %d.\n",
113 				hest_hdr->source_id);
114 			return -EINVAL;
115 		}
116 
117 		rc = func(hest_hdr, data);
118 		if (rc)
119 			return rc;
120 
121 		hest_hdr = (void *)hest_hdr + len;
122 	}
123 
124 	return 0;
125 }
126 EXPORT_SYMBOL_GPL(apei_hest_parse);
127 
128 /*
129  * Check if firmware advertises firmware first mode. We need FF bit to be set
130  * along with a set of MC banks which work in FF mode.
131  */
132 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
133 {
134 	if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
135 		return 0;
136 
137 	if (!acpi_disable_cmcff)
138 		return !arch_apei_enable_cmcff(hest_hdr, data);
139 
140 	return 0;
141 }
142 
143 struct ghes_arr {
144 	struct platform_device **ghes_devs;
145 	unsigned int count;
146 };
147 
148 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
149 {
150 	int *count = data;
151 
152 	if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR ||
153 	    hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR_V2)
154 		(*count)++;
155 	return 0;
156 }
157 
158 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
159 {
160 	struct platform_device *ghes_dev;
161 	struct ghes_arr *ghes_arr = data;
162 	int rc, i;
163 
164 	if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR &&
165 	    hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR_V2)
166 		return 0;
167 
168 	if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
169 		return 0;
170 	for (i = 0; i < ghes_arr->count; i++) {
171 		struct acpi_hest_header *hdr;
172 		ghes_dev = ghes_arr->ghes_devs[i];
173 		hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
174 		if (hdr->source_id == hest_hdr->source_id) {
175 			pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
176 				   hdr->source_id);
177 			return -EIO;
178 		}
179 	}
180 	ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
181 	if (!ghes_dev)
182 		return -ENOMEM;
183 
184 	rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
185 	if (rc)
186 		goto err;
187 
188 	rc = platform_device_add(ghes_dev);
189 	if (rc)
190 		goto err;
191 	ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
192 
193 	return 0;
194 err:
195 	platform_device_put(ghes_dev);
196 	return rc;
197 }
198 
199 static int __init hest_ghes_dev_register(unsigned int ghes_count)
200 {
201 	int rc, i;
202 	struct ghes_arr ghes_arr;
203 
204 	ghes_arr.count = 0;
205 	ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *),
206 					   GFP_KERNEL);
207 	if (!ghes_arr.ghes_devs)
208 		return -ENOMEM;
209 
210 	rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
211 	if (rc)
212 		goto err;
213 
214 	rc = ghes_estatus_pool_init(ghes_count);
215 	if (rc)
216 		goto err;
217 
218 out:
219 	kfree(ghes_arr.ghes_devs);
220 	return rc;
221 err:
222 	for (i = 0; i < ghes_arr.count; i++)
223 		platform_device_unregister(ghes_arr.ghes_devs[i]);
224 	goto out;
225 }
226 
227 static int __init setup_hest_disable(char *str)
228 {
229 	hest_disable = HEST_DISABLED;
230 	return 0;
231 }
232 
233 __setup("hest_disable", setup_hest_disable);
234 
235 void __init acpi_hest_init(void)
236 {
237 	acpi_status status;
238 	int rc = -ENODEV;
239 	unsigned int ghes_count = 0;
240 
241 	if (hest_disable) {
242 		pr_info(HEST_PFX "Table parsing disabled.\n");
243 		return;
244 	}
245 
246 	status = acpi_get_table(ACPI_SIG_HEST, 0,
247 				(struct acpi_table_header **)&hest_tab);
248 	if (status == AE_NOT_FOUND) {
249 		hest_disable = HEST_NOT_FOUND;
250 		return;
251 	} else if (ACPI_FAILURE(status)) {
252 		const char *msg = acpi_format_exception(status);
253 		pr_err(HEST_PFX "Failed to get table, %s\n", msg);
254 		rc = -EINVAL;
255 		goto err;
256 	}
257 
258 	rc = apei_hest_parse(hest_parse_cmc, NULL);
259 	if (rc)
260 		goto err;
261 
262 	if (!ghes_disable) {
263 		rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
264 		if (rc)
265 			goto err;
266 
267 		if (ghes_count)
268 			rc = hest_ghes_dev_register(ghes_count);
269 		if (rc)
270 			goto err;
271 	}
272 
273 	pr_info(HEST_PFX "Table parsing has been initialized.\n");
274 	return;
275 err:
276 	hest_disable = HEST_DISABLED;
277 }
278