xref: /openbmc/linux/drivers/acpi/apei/hest.c (revision 275876e2)
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 
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 
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 || !hest_tab)
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 /*
125  * Check if firmware advertises firmware first mode. We need FF bit to be set
126  * along with a set of MC banks which work in FF mode.
127  */
128 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
129 {
130 	return arch_apei_enable_cmcff(hest_hdr, data);
131 }
132 
133 struct ghes_arr {
134 	struct platform_device **ghes_devs;
135 	unsigned int count;
136 };
137 
138 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
139 {
140 	int *count = data;
141 
142 	if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR)
143 		(*count)++;
144 	return 0;
145 }
146 
147 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
148 {
149 	struct platform_device *ghes_dev;
150 	struct ghes_arr *ghes_arr = data;
151 	int rc, i;
152 
153 	if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
154 		return 0;
155 
156 	if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
157 		return 0;
158 	for (i = 0; i < ghes_arr->count; i++) {
159 		struct acpi_hest_header *hdr;
160 		ghes_dev = ghes_arr->ghes_devs[i];
161 		hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
162 		if (hdr->source_id == hest_hdr->source_id) {
163 			pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
164 				   hdr->source_id);
165 			return -EIO;
166 		}
167 	}
168 	ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
169 	if (!ghes_dev)
170 		return -ENOMEM;
171 
172 	rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
173 	if (rc)
174 		goto err;
175 
176 	rc = platform_device_add(ghes_dev);
177 	if (rc)
178 		goto err;
179 	ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
180 
181 	return 0;
182 err:
183 	platform_device_put(ghes_dev);
184 	return rc;
185 }
186 
187 static int __init hest_ghes_dev_register(unsigned int ghes_count)
188 {
189 	int rc, i;
190 	struct ghes_arr ghes_arr;
191 
192 	ghes_arr.count = 0;
193 	ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL);
194 	if (!ghes_arr.ghes_devs)
195 		return -ENOMEM;
196 
197 	rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
198 	if (rc)
199 		goto err;
200 out:
201 	kfree(ghes_arr.ghes_devs);
202 	return rc;
203 err:
204 	for (i = 0; i < ghes_arr.count; i++)
205 		platform_device_unregister(ghes_arr.ghes_devs[i]);
206 	goto out;
207 }
208 
209 static int __init setup_hest_disable(char *str)
210 {
211 	hest_disable = 1;
212 	return 0;
213 }
214 
215 __setup("hest_disable", setup_hest_disable);
216 
217 void __init acpi_hest_init(void)
218 {
219 	acpi_status status;
220 	int rc = -ENODEV;
221 	unsigned int ghes_count = 0;
222 
223 	if (hest_disable) {
224 		pr_info(HEST_PFX "Table parsing disabled.\n");
225 		return;
226 	}
227 
228 	status = acpi_get_table(ACPI_SIG_HEST, 0,
229 				(struct acpi_table_header **)&hest_tab);
230 	if (status == AE_NOT_FOUND)
231 		goto err;
232 	else if (ACPI_FAILURE(status)) {
233 		const char *msg = acpi_format_exception(status);
234 		pr_err(HEST_PFX "Failed to get table, %s\n", msg);
235 		rc = -EINVAL;
236 		goto err;
237 	}
238 
239 	if (!acpi_disable_cmcff)
240 		apei_hest_parse(hest_parse_cmc, NULL);
241 
242 	if (!ghes_disable) {
243 		rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
244 		if (rc)
245 			goto err;
246 		rc = hest_ghes_dev_register(ghes_count);
247 		if (rc)
248 			goto err;
249 	}
250 
251 	pr_info(HEST_PFX "Table parsing has been initialized.\n");
252 	return;
253 err:
254 	hest_disable = 1;
255 }
256