xref: /openbmc/linux/drivers/acpi/apei/hest.c (revision e15a5365)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * APEI Hardware Error Souce 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 
52 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
53 {
54 	u16 hest_type = hest_hdr->type;
55 	int len;
56 
57 	if (hest_type >= ACPI_HEST_TYPE_RESERVED)
58 		return 0;
59 
60 	len = hest_esrc_len_tab[hest_type];
61 
62 	if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
63 		struct acpi_hest_ia_corrected *cmc;
64 		cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
65 		len = sizeof(*cmc) + cmc->num_hardware_banks *
66 			sizeof(struct acpi_hest_ia_error_bank);
67 	} else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
68 		struct acpi_hest_ia_machine_check *mc;
69 		mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
70 		len = sizeof(*mc) + mc->num_hardware_banks *
71 			sizeof(struct acpi_hest_ia_error_bank);
72 	} else if (hest_type == ACPI_HEST_TYPE_IA32_DEFERRED_CHECK) {
73 		struct acpi_hest_ia_deferred_check *mc;
74 		mc = (struct acpi_hest_ia_deferred_check *)hest_hdr;
75 		len = sizeof(*mc) + mc->num_hardware_banks *
76 			sizeof(struct acpi_hest_ia_error_bank);
77 	}
78 	BUG_ON(len == -1);
79 
80 	return len;
81 };
82 
83 int apei_hest_parse(apei_hest_func_t func, void *data)
84 {
85 	struct acpi_hest_header *hest_hdr;
86 	int i, rc, len;
87 
88 	if (hest_disable || !hest_tab)
89 		return -EINVAL;
90 
91 	hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
92 	for (i = 0; i < hest_tab->error_source_count; i++) {
93 		len = hest_esrc_len(hest_hdr);
94 		if (!len) {
95 			pr_warn(FW_WARN HEST_PFX
96 				"Unknown or unused hardware error source "
97 				"type: %d for hardware error source: %d.\n",
98 				hest_hdr->type, hest_hdr->source_id);
99 			return -EINVAL;
100 		}
101 		if ((void *)hest_hdr + len >
102 		    (void *)hest_tab + hest_tab->header.length) {
103 			pr_warn(FW_BUG HEST_PFX
104 		"Table contents overflow for hardware error source: %d.\n",
105 				hest_hdr->source_id);
106 			return -EINVAL;
107 		}
108 
109 		rc = func(hest_hdr, data);
110 		if (rc)
111 			return rc;
112 
113 		hest_hdr = (void *)hest_hdr + len;
114 	}
115 
116 	return 0;
117 }
118 EXPORT_SYMBOL_GPL(apei_hest_parse);
119 
120 /*
121  * Check if firmware advertises firmware first mode. We need FF bit to be set
122  * along with a set of MC banks which work in FF mode.
123  */
124 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
125 {
126 	if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
127 		return 0;
128 
129 	if (!acpi_disable_cmcff)
130 		return !arch_apei_enable_cmcff(hest_hdr, data);
131 
132 	return 0;
133 }
134 
135 struct ghes_arr {
136 	struct platform_device **ghes_devs;
137 	unsigned int count;
138 };
139 
140 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
141 {
142 	int *count = data;
143 
144 	if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR ||
145 	    hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR_V2)
146 		(*count)++;
147 	return 0;
148 }
149 
150 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
151 {
152 	struct platform_device *ghes_dev;
153 	struct ghes_arr *ghes_arr = data;
154 	int rc, i;
155 
156 	if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR &&
157 	    hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR_V2)
158 		return 0;
159 
160 	if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
161 		return 0;
162 	for (i = 0; i < ghes_arr->count; i++) {
163 		struct acpi_hest_header *hdr;
164 		ghes_dev = ghes_arr->ghes_devs[i];
165 		hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
166 		if (hdr->source_id == hest_hdr->source_id) {
167 			pr_warn(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
168 				hdr->source_id);
169 			return -EIO;
170 		}
171 	}
172 	ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
173 	if (!ghes_dev)
174 		return -ENOMEM;
175 
176 	rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
177 	if (rc)
178 		goto err;
179 
180 	rc = platform_device_add(ghes_dev);
181 	if (rc)
182 		goto err;
183 	ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
184 
185 	return 0;
186 err:
187 	platform_device_put(ghes_dev);
188 	return rc;
189 }
190 
191 static int __init hest_ghes_dev_register(unsigned int ghes_count)
192 {
193 	int rc, i;
194 	struct ghes_arr ghes_arr;
195 
196 	ghes_arr.count = 0;
197 	ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *),
198 					   GFP_KERNEL);
199 	if (!ghes_arr.ghes_devs)
200 		return -ENOMEM;
201 
202 	rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
203 	if (rc)
204 		goto err;
205 
206 	rc = ghes_estatus_pool_init(ghes_count);
207 	if (rc)
208 		goto err;
209 
210 out:
211 	kfree(ghes_arr.ghes_devs);
212 	return rc;
213 err:
214 	for (i = 0; i < ghes_arr.count; i++)
215 		platform_device_unregister(ghes_arr.ghes_devs[i]);
216 	goto out;
217 }
218 
219 static int __init setup_hest_disable(char *str)
220 {
221 	hest_disable = HEST_DISABLED;
222 	return 0;
223 }
224 
225 __setup("hest_disable", setup_hest_disable);
226 
227 void __init acpi_hest_init(void)
228 {
229 	acpi_status status;
230 	int rc;
231 	unsigned int ghes_count = 0;
232 
233 	if (hest_disable) {
234 		pr_info(HEST_PFX "Table parsing disabled.\n");
235 		return;
236 	}
237 
238 	status = acpi_get_table(ACPI_SIG_HEST, 0,
239 				(struct acpi_table_header **)&hest_tab);
240 	if (status == AE_NOT_FOUND) {
241 		hest_disable = HEST_NOT_FOUND;
242 		return;
243 	} else if (ACPI_FAILURE(status)) {
244 		const char *msg = acpi_format_exception(status);
245 		pr_err(HEST_PFX "Failed to get table, %s\n", msg);
246 		hest_disable = HEST_DISABLED;
247 		return;
248 	}
249 
250 	rc = apei_hest_parse(hest_parse_cmc, NULL);
251 	if (rc)
252 		goto err;
253 
254 	if (!ghes_disable) {
255 		rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
256 		if (rc)
257 			goto err;
258 
259 		if (ghes_count)
260 			rc = hest_ghes_dev_register(ghes_count);
261 		if (rc)
262 			goto err;
263 	}
264 
265 	pr_info(HEST_PFX "Table parsing has been initialized.\n");
266 	return;
267 err:
268 	hest_disable = HEST_DISABLED;
269 	acpi_put_table((struct acpi_table_header *)hest_tab);
270 }
271