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 36 #include "apei-internal.h" 37 38 #define HEST_PFX "HEST: " 39 40 bool hest_disable; 41 EXPORT_SYMBOL_GPL(hest_disable); 42 43 /* HEST table parsing */ 44 45 static struct acpi_table_hest *__read_mostly hest_tab; 46 47 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = { 48 [ACPI_HEST_TYPE_IA32_CHECK] = -1, /* need further calculation */ 49 [ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1, 50 [ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi), 51 [ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root), 52 [ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer), 53 [ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge), 54 [ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic), 55 }; 56 57 static int hest_esrc_len(struct acpi_hest_header *hest_hdr) 58 { 59 u16 hest_type = hest_hdr->type; 60 int len; 61 62 if (hest_type >= ACPI_HEST_TYPE_RESERVED) 63 return 0; 64 65 len = hest_esrc_len_tab[hest_type]; 66 67 if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) { 68 struct acpi_hest_ia_corrected *cmc; 69 cmc = (struct acpi_hest_ia_corrected *)hest_hdr; 70 len = sizeof(*cmc) + cmc->num_hardware_banks * 71 sizeof(struct acpi_hest_ia_error_bank); 72 } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) { 73 struct acpi_hest_ia_machine_check *mc; 74 mc = (struct acpi_hest_ia_machine_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_warning(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_warning(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 return arch_apei_enable_cmcff(hest_hdr, data); 127 } 128 129 struct ghes_arr { 130 struct platform_device **ghes_devs; 131 unsigned int count; 132 }; 133 134 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data) 135 { 136 int *count = data; 137 138 if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR) 139 (*count)++; 140 return 0; 141 } 142 143 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data) 144 { 145 struct platform_device *ghes_dev; 146 struct ghes_arr *ghes_arr = data; 147 int rc, i; 148 149 if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR) 150 return 0; 151 152 if (!((struct acpi_hest_generic *)hest_hdr)->enabled) 153 return 0; 154 for (i = 0; i < ghes_arr->count; i++) { 155 struct acpi_hest_header *hdr; 156 ghes_dev = ghes_arr->ghes_devs[i]; 157 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data; 158 if (hdr->source_id == hest_hdr->source_id) { 159 pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n", 160 hdr->source_id); 161 return -EIO; 162 } 163 } 164 ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id); 165 if (!ghes_dev) 166 return -ENOMEM; 167 168 rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *)); 169 if (rc) 170 goto err; 171 172 rc = platform_device_add(ghes_dev); 173 if (rc) 174 goto err; 175 ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev; 176 177 return 0; 178 err: 179 platform_device_put(ghes_dev); 180 return rc; 181 } 182 183 static int __init hest_ghes_dev_register(unsigned int ghes_count) 184 { 185 int rc, i; 186 struct ghes_arr ghes_arr; 187 188 ghes_arr.count = 0; 189 ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL); 190 if (!ghes_arr.ghes_devs) 191 return -ENOMEM; 192 193 rc = apei_hest_parse(hest_parse_ghes, &ghes_arr); 194 if (rc) 195 goto err; 196 out: 197 kfree(ghes_arr.ghes_devs); 198 return rc; 199 err: 200 for (i = 0; i < ghes_arr.count; i++) 201 platform_device_unregister(ghes_arr.ghes_devs[i]); 202 goto out; 203 } 204 205 static int __init setup_hest_disable(char *str) 206 { 207 hest_disable = 1; 208 return 0; 209 } 210 211 __setup("hest_disable", setup_hest_disable); 212 213 void __init acpi_hest_init(void) 214 { 215 acpi_status status; 216 int rc = -ENODEV; 217 unsigned int ghes_count = 0; 218 219 if (hest_disable) { 220 pr_info(HEST_PFX "Table parsing disabled.\n"); 221 return; 222 } 223 224 status = acpi_get_table(ACPI_SIG_HEST, 0, 225 (struct acpi_table_header **)&hest_tab); 226 if (status == AE_NOT_FOUND) 227 goto err; 228 else if (ACPI_FAILURE(status)) { 229 const char *msg = acpi_format_exception(status); 230 pr_err(HEST_PFX "Failed to get table, %s\n", msg); 231 rc = -EINVAL; 232 goto err; 233 } 234 235 if (!acpi_disable_cmcff) 236 apei_hest_parse(hest_parse_cmc, NULL); 237 238 if (!ghes_disable) { 239 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count); 240 if (rc) 241 goto err; 242 rc = hest_ghes_dev_register(ghes_count); 243 if (rc) 244 goto err; 245 } 246 247 pr_info(HEST_PFX "Table parsing has been initialized.\n"); 248 return; 249 err: 250 hest_disable = 1; 251 } 252