xref: /linux/drivers/acpi/apei/hest.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
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 #include <asm/mce.h>
40 
41 #include "apei-internal.h"
42 
43 #define HEST_PFX "HEST: "
44 
45 bool hest_disable;
46 EXPORT_SYMBOL_GPL(hest_disable);
47 
48 /* HEST table parsing */
49 
50 static struct acpi_table_hest *__read_mostly hest_tab;
51 
52 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
53 	[ACPI_HEST_TYPE_IA32_CHECK] = -1,	/* need further calculation */
54 	[ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
55 	[ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
56 	[ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
57 	[ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
58 	[ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
59 	[ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
60 };
61 
62 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
63 {
64 	u16 hest_type = hest_hdr->type;
65 	int len;
66 
67 	if (hest_type >= ACPI_HEST_TYPE_RESERVED)
68 		return 0;
69 
70 	len = hest_esrc_len_tab[hest_type];
71 
72 	if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
73 		struct acpi_hest_ia_corrected *cmc;
74 		cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
75 		len = sizeof(*cmc) + cmc->num_hardware_banks *
76 			sizeof(struct acpi_hest_ia_error_bank);
77 	} else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
78 		struct acpi_hest_ia_machine_check *mc;
79 		mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
80 		len = sizeof(*mc) + mc->num_hardware_banks *
81 			sizeof(struct acpi_hest_ia_error_bank);
82 	}
83 	BUG_ON(len == -1);
84 
85 	return len;
86 };
87 
88 int apei_hest_parse(apei_hest_func_t func, void *data)
89 {
90 	struct acpi_hest_header *hest_hdr;
91 	int i, rc, len;
92 
93 	if (hest_disable || !hest_tab)
94 		return -EINVAL;
95 
96 	hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
97 	for (i = 0; i < hest_tab->error_source_count; i++) {
98 		len = hest_esrc_len(hest_hdr);
99 		if (!len) {
100 			pr_warning(FW_WARN HEST_PFX
101 				   "Unknown or unused hardware error source "
102 				   "type: %d for hardware error source: %d.\n",
103 				   hest_hdr->type, hest_hdr->source_id);
104 			return -EINVAL;
105 		}
106 		if ((void *)hest_hdr + len >
107 		    (void *)hest_tab + hest_tab->header.length) {
108 			pr_warning(FW_BUG HEST_PFX
109 		"Table contents overflow for hardware error source: %d.\n",
110 				hest_hdr->source_id);
111 			return -EINVAL;
112 		}
113 
114 		rc = func(hest_hdr, data);
115 		if (rc)
116 			return rc;
117 
118 		hest_hdr = (void *)hest_hdr + len;
119 	}
120 
121 	return 0;
122 }
123 EXPORT_SYMBOL_GPL(apei_hest_parse);
124 
125 /*
126  * Check if firmware advertises firmware first mode. We need FF bit to be set
127  * along with a set of MC banks which work in FF mode.
128  */
129 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
130 {
131 #ifdef CONFIG_X86_MCE
132 	int i;
133 	struct acpi_hest_ia_corrected *cmc;
134 	struct acpi_hest_ia_error_bank *mc_bank;
135 
136 	if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
137 		return 0;
138 
139 	cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
140 	if (!cmc->enabled)
141 		return 0;
142 
143 	/*
144 	 * We expect HEST to provide a list of MC banks that report errors
145 	 * in firmware first mode. Otherwise, return non-zero value to
146 	 * indicate that we are done parsing HEST.
147 	 */
148 	if (!(cmc->flags & ACPI_HEST_FIRMWARE_FIRST) || !cmc->num_hardware_banks)
149 		return 1;
150 
151 	pr_info(HEST_PFX "Enabling Firmware First mode for corrected errors.\n");
152 
153 	mc_bank = (struct acpi_hest_ia_error_bank *)(cmc + 1);
154 	for (i = 0; i < cmc->num_hardware_banks; i++, mc_bank++)
155 		mce_disable_bank(mc_bank->bank_number);
156 #endif
157 	return 1;
158 }
159 
160 struct ghes_arr {
161 	struct platform_device **ghes_devs;
162 	unsigned int count;
163 };
164 
165 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
166 {
167 	int *count = data;
168 
169 	if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR)
170 		(*count)++;
171 	return 0;
172 }
173 
174 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
175 {
176 	struct platform_device *ghes_dev;
177 	struct ghes_arr *ghes_arr = data;
178 	int rc, i;
179 
180 	if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
181 		return 0;
182 
183 	if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
184 		return 0;
185 	for (i = 0; i < ghes_arr->count; i++) {
186 		struct acpi_hest_header *hdr;
187 		ghes_dev = ghes_arr->ghes_devs[i];
188 		hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
189 		if (hdr->source_id == hest_hdr->source_id) {
190 			pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
191 				   hdr->source_id);
192 			return -EIO;
193 		}
194 	}
195 	ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
196 	if (!ghes_dev)
197 		return -ENOMEM;
198 
199 	rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
200 	if (rc)
201 		goto err;
202 
203 	rc = platform_device_add(ghes_dev);
204 	if (rc)
205 		goto err;
206 	ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
207 
208 	return 0;
209 err:
210 	platform_device_put(ghes_dev);
211 	return rc;
212 }
213 
214 static int __init hest_ghes_dev_register(unsigned int ghes_count)
215 {
216 	int rc, i;
217 	struct ghes_arr ghes_arr;
218 
219 	ghes_arr.count = 0;
220 	ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL);
221 	if (!ghes_arr.ghes_devs)
222 		return -ENOMEM;
223 
224 	rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
225 	if (rc)
226 		goto err;
227 out:
228 	kfree(ghes_arr.ghes_devs);
229 	return rc;
230 err:
231 	for (i = 0; i < ghes_arr.count; i++)
232 		platform_device_unregister(ghes_arr.ghes_devs[i]);
233 	goto out;
234 }
235 
236 static int __init setup_hest_disable(char *str)
237 {
238 	hest_disable = 1;
239 	return 0;
240 }
241 
242 __setup("hest_disable", setup_hest_disable);
243 
244 void __init acpi_hest_init(void)
245 {
246 	acpi_status status;
247 	int rc = -ENODEV;
248 	unsigned int ghes_count = 0;
249 
250 	if (hest_disable) {
251 		pr_info(HEST_PFX "Table parsing disabled.\n");
252 		return;
253 	}
254 
255 	status = acpi_get_table(ACPI_SIG_HEST, 0,
256 				(struct acpi_table_header **)&hest_tab);
257 	if (status == AE_NOT_FOUND)
258 		goto err;
259 	else if (ACPI_FAILURE(status)) {
260 		const char *msg = acpi_format_exception(status);
261 		pr_err(HEST_PFX "Failed to get table, %s\n", msg);
262 		rc = -EINVAL;
263 		goto err;
264 	}
265 
266 	if (!acpi_disable_cmcff)
267 		apei_hest_parse(hest_parse_cmc, NULL);
268 
269 	if (!ghes_disable) {
270 		rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
271 		if (rc)
272 			goto err;
273 		rc = hest_ghes_dev_register(ghes_count);
274 		if (rc)
275 			goto err;
276 	}
277 
278 	pr_info(HEST_PFX "Table parsing has been initialized.\n");
279 	return;
280 err:
281 	hest_disable = 1;
282 }
283