drivers/acpi/apei/hest.c

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