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 = -ENODEV; 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