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 33int hest_disable; 34EXPORT_SYMBOL_GPL(hest_disable); 35 36/* HEST table parsing */ 37 38static struct acpi_table_hest *__read_mostly hest_tab; 39 40static 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 52static 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 58static 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 89typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data); 90 91static int apei_hest_parse(apei_hest_func_t func, void *data) 92{ 93 struct acpi_hest_header *hest_hdr; 94 int i, rc, len; 95 96 if (hest_disable || !hest_tab) 97 return -EINVAL; 98 99 hest_hdr = (struct acpi_hest_header *)(hest_tab + 1); 100 for (i = 0; i < hest_tab->error_source_count; i++) { 101 len = hest_esrc_len(hest_hdr); 102 if (!len) { 103 pr_warn(FW_WARN HEST_PFX 104 "Unknown or unused hardware error source " 105 "type: %d for hardware error source: %d.\n", 106 hest_hdr->type, hest_hdr->source_id); 107 return -EINVAL; 108 } 109 if ((void *)hest_hdr + len > 110 (void *)hest_tab + hest_tab->header.length) { 111 pr_warn(FW_BUG HEST_PFX 112 "Table contents overflow for hardware error source: %d.\n", 113 hest_hdr->source_id); 114 return -EINVAL; 115 } 116 117 rc = func(hest_hdr, data); 118 if (rc) 119 return rc; 120 121 hest_hdr = (void *)hest_hdr + len; 122 } 123 124 return 0; 125} 126 127/* 128 * Check if firmware advertises firmware first mode. We need FF bit to be set 129 * along with a set of MC banks which work in FF mode. 130 */ 131static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data) 132{ 133 if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) 134 return 0; 135 136 if (!acpi_disable_cmcff) 137 return !arch_apei_enable_cmcff(hest_hdr, data); 138 139 return 0; 140} 141 142struct ghes_arr { 143 struct platform_device **ghes_devs; 144 unsigned int count; 145}; 146 147static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data) 148{ 149 int *count = data; 150 151 if (is_generic_error(hest_hdr)) 152 (*count)++; 153 return 0; 154} 155 156static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data) 157{ 158 struct platform_device *ghes_dev; 159 struct ghes_arr *ghes_arr = data; 160 int rc, i; 161 162 if (!is_generic_error(hest_hdr)) 163 return 0; 164 165 if (!((struct acpi_hest_generic *)hest_hdr)->enabled) 166 return 0; 167 for (i = 0; i < ghes_arr->count; i++) { 168 struct acpi_hest_header *hdr; 169 ghes_dev = ghes_arr->ghes_devs[i]; 170 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data; 171 if (hdr->source_id == hest_hdr->source_id) { 172 pr_warn(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n", 173 hdr->source_id); 174 return -EIO; 175 } 176 } 177 ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id); 178 if (!ghes_dev) 179 return -ENOMEM; 180 181 rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *)); 182 if (rc) 183 goto err; 184 185 rc = platform_device_add(ghes_dev); 186 if (rc) 187 goto err; 188 ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev; 189 190 return 0; 191err: 192 platform_device_put(ghes_dev); 193 return rc; 194} 195 196static int __init hest_ghes_dev_register(unsigned int ghes_count) 197{ 198 int rc, i; 199 struct ghes_arr ghes_arr; 200 201 ghes_arr.count = 0; 202 ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *), 203 GFP_KERNEL); 204 if (!ghes_arr.ghes_devs) 205 return -ENOMEM; 206 207 rc = apei_hest_parse(hest_parse_ghes, &ghes_arr); 208 if (rc) 209 goto err; 210 211 rc = ghes_estatus_pool_init(ghes_count); 212 if (rc) 213 goto err; 214 215out: 216 kfree(ghes_arr.ghes_devs); 217 return rc; 218err: 219 for (i = 0; i < ghes_arr.count; i++) 220 platform_device_unregister(ghes_arr.ghes_devs[i]); 221 goto out; 222} 223 224static int __init setup_hest_disable(char *str) 225{ 226 hest_disable = HEST_DISABLED; 227 return 1; 228} 229 230__setup("hest_disable", setup_hest_disable); 231 232void __init acpi_hest_init(void) 233{ 234 acpi_status status; 235 int rc; 236 unsigned int ghes_count = 0; 237 238 if (hest_disable) { 239 pr_info(HEST_PFX "Table parsing disabled.\n"); 240 return; 241 } 242 243 status = acpi_get_table(ACPI_SIG_HEST, 0, 244 (struct acpi_table_header **)&hest_tab); 245 if (status == AE_NOT_FOUND) { 246 hest_disable = HEST_NOT_FOUND; 247 return; 248 } else if (ACPI_FAILURE(status)) { 249 const char *msg = acpi_format_exception(status); 250 pr_err(HEST_PFX "Failed to get table, %s\n", msg); 251 hest_disable = HEST_DISABLED; 252 return; 253 } 254 255 rc = apei_hest_parse(hest_parse_cmc, NULL); 256 if (rc) 257 goto err; 258 259 if (!ghes_disable) { 260 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count); 261 if (rc) 262 goto err; 263 264 if (ghes_count) 265 rc = hest_ghes_dev_register(ghes_count); 266 if (rc) 267 goto err; 268 } 269 270 pr_info(HEST_PFX "Table parsing has been initialized.\n"); 271 return; 272err: 273 hest_disable = HEST_DISABLED; 274 acpi_put_table((struct acpi_table_header *)hest_tab); 275} 276