1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * APEI Hardware Error Source 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 inline bool is_generic_error(struct acpi_hest_header *hest_hdr) 53 { 54 return hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR || 55 hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR_V2; 56 } 57 58 static int hest_esrc_len(struct acpi_hest_header *hest_hdr) 59 { 60 u16 hest_type = hest_hdr->type; 61 int len; 62 63 if (hest_type >= ACPI_HEST_TYPE_RESERVED) 64 return 0; 65 66 len = hest_esrc_len_tab[hest_type]; 67 68 if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) { 69 struct acpi_hest_ia_corrected *cmc; 70 cmc = (struct acpi_hest_ia_corrected *)hest_hdr; 71 len = sizeof(*cmc) + cmc->num_hardware_banks * 72 sizeof(struct acpi_hest_ia_error_bank); 73 } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) { 74 struct acpi_hest_ia_machine_check *mc; 75 mc = (struct acpi_hest_ia_machine_check *)hest_hdr; 76 len = sizeof(*mc) + mc->num_hardware_banks * 77 sizeof(struct acpi_hest_ia_error_bank); 78 } else if (hest_type == ACPI_HEST_TYPE_IA32_DEFERRED_CHECK) { 79 struct acpi_hest_ia_deferred_check *mc; 80 mc = (struct acpi_hest_ia_deferred_check *)hest_hdr; 81 len = sizeof(*mc) + mc->num_hardware_banks * 82 sizeof(struct acpi_hest_ia_error_bank); 83 } 84 BUG_ON(len == -1); 85 86 return len; 87 }; 88 89 int apei_hest_parse(apei_hest_func_t func, void *data) 90 { 91 struct acpi_hest_header *hest_hdr; 92 int i, rc, len; 93 94 if (hest_disable || !hest_tab) 95 return -EINVAL; 96 97 hest_hdr = (struct acpi_hest_header *)(hest_tab + 1); 98 for (i = 0; i < hest_tab->error_source_count; i++) { 99 len = hest_esrc_len(hest_hdr); 100 if (!len) { 101 pr_warn(FW_WARN HEST_PFX 102 "Unknown or unused hardware error source " 103 "type: %d for hardware error source: %d.\n", 104 hest_hdr->type, hest_hdr->source_id); 105 return -EINVAL; 106 } 107 if ((void *)hest_hdr + len > 108 (void *)hest_tab + hest_tab->header.length) { 109 pr_warn(FW_BUG HEST_PFX 110 "Table contents overflow for hardware error source: %d.\n", 111 hest_hdr->source_id); 112 return -EINVAL; 113 } 114 115 rc = func(hest_hdr, data); 116 if (rc) 117 return rc; 118 119 hest_hdr = (void *)hest_hdr + len; 120 } 121 122 return 0; 123 } 124 EXPORT_SYMBOL_GPL(apei_hest_parse); 125 126 /* 127 * Check if firmware advertises firmware first mode. We need FF bit to be set 128 * along with a set of MC banks which work in FF mode. 129 */ 130 static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data) 131 { 132 if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) 133 return 0; 134 135 if (!acpi_disable_cmcff) 136 return !arch_apei_enable_cmcff(hest_hdr, data); 137 138 return 0; 139 } 140 141 struct ghes_arr { 142 struct platform_device **ghes_devs; 143 unsigned int count; 144 }; 145 146 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data) 147 { 148 int *count = data; 149 150 if (is_generic_error(hest_hdr)) 151 (*count)++; 152 return 0; 153 } 154 155 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data) 156 { 157 struct platform_device *ghes_dev; 158 struct ghes_arr *ghes_arr = data; 159 int rc, i; 160 161 if (!is_generic_error(hest_hdr)) 162 return 0; 163 164 if (!((struct acpi_hest_generic *)hest_hdr)->enabled) 165 return 0; 166 for (i = 0; i < ghes_arr->count; i++) { 167 struct acpi_hest_header *hdr; 168 ghes_dev = ghes_arr->ghes_devs[i]; 169 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data; 170 if (hdr->source_id == hest_hdr->source_id) { 171 pr_warn(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n", 172 hdr->source_id); 173 return -EIO; 174 } 175 } 176 ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id); 177 if (!ghes_dev) 178 return -ENOMEM; 179 180 rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *)); 181 if (rc) 182 goto err; 183 184 rc = platform_device_add(ghes_dev); 185 if (rc) 186 goto err; 187 ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev; 188 189 return 0; 190 err: 191 platform_device_put(ghes_dev); 192 return rc; 193 } 194 195 static int __init hest_ghes_dev_register(unsigned int ghes_count) 196 { 197 int rc, i; 198 struct ghes_arr ghes_arr; 199 200 ghes_arr.count = 0; 201 ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *), 202 GFP_KERNEL); 203 if (!ghes_arr.ghes_devs) 204 return -ENOMEM; 205 206 rc = apei_hest_parse(hest_parse_ghes, &ghes_arr); 207 if (rc) 208 goto err; 209 210 rc = ghes_estatus_pool_init(ghes_count); 211 if (rc) 212 goto err; 213 214 out: 215 kfree(ghes_arr.ghes_devs); 216 return rc; 217 err: 218 for (i = 0; i < ghes_arr.count; i++) 219 platform_device_unregister(ghes_arr.ghes_devs[i]); 220 goto out; 221 } 222 223 static int __init setup_hest_disable(char *str) 224 { 225 hest_disable = HEST_DISABLED; 226 return 0; 227 } 228 229 __setup("hest_disable", setup_hest_disable); 230 231 void __init acpi_hest_init(void) 232 { 233 acpi_status status; 234 int rc; 235 unsigned int ghes_count = 0; 236 237 if (hest_disable) { 238 pr_info(HEST_PFX "Table parsing disabled.\n"); 239 return; 240 } 241 242 status = acpi_get_table(ACPI_SIG_HEST, 0, 243 (struct acpi_table_header **)&hest_tab); 244 if (status == AE_NOT_FOUND) { 245 hest_disable = HEST_NOT_FOUND; 246 return; 247 } else if (ACPI_FAILURE(status)) { 248 const char *msg = acpi_format_exception(status); 249 pr_err(HEST_PFX "Failed to get table, %s\n", msg); 250 hest_disable = HEST_DISABLED; 251 return; 252 } 253 254 rc = apei_hest_parse(hest_parse_cmc, NULL); 255 if (rc) 256 goto err; 257 258 if (!ghes_disable) { 259 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count); 260 if (rc) 261 goto err; 262 263 if (ghes_count) 264 rc = hest_ghes_dev_register(ghes_count); 265 if (rc) 266 goto err; 267 } 268 269 pr_info(HEST_PFX "Table parsing has been initialized.\n"); 270 return; 271 err: 272 hest_disable = HEST_DISABLED; 273 acpi_put_table((struct acpi_table_header *)hest_tab); 274 } 275