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  * You should have received a copy of the GNU General Public License
  26  * along with this program; if not, write to the Free Software
  27  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  28  */
  29
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/init.h>
  33 #include <linux/acpi.h>
  34 #include <linux/kdebug.h>
  35 #include <linux/highmem.h>
  36 #include <linux/io.h>
  37 #include <linux/platform_device.h>
  38 #include <acpi/apei.h>
  39
  40 #include "apei-internal.h"
  41
  42 #define HEST_PFX "HEST: "
  43
  44 bool hest_disable;
  45 EXPORT_SYMBOL_GPL(hest_disable);
  46
  47 /* HEST table parsing */
  48
  49 static struct acpi_table_hest *__read_mostly hest_tab;
  50
  51 static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
  52         [ACPI_HEST_TYPE_IA32_CHECK] = -1,       /* need further calculation */
  53         [ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
  54         [ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
  55         [ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
  56         [ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
  57         [ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
  58         [ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
  59 };
  60
  61 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
  62 {
  63         u16 hest_type = hest_hdr->type;
  64         int len;
  65
  66         if (hest_type >= ACPI_HEST_TYPE_RESERVED)
  67                 return 0;
  68
  69         len = hest_esrc_len_tab[hest_type];
  70
  71         if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
  72                 struct acpi_hest_ia_corrected *cmc;
  73                 cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
  74                 len = sizeof(*cmc) + cmc->num_hardware_banks *
  75                         sizeof(struct acpi_hest_ia_error_bank);
  76         } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
  77                 struct acpi_hest_ia_machine_check *mc;
  78                 mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
  79                 len = sizeof(*mc) + mc->num_hardware_banks *
  80                         sizeof(struct acpi_hest_ia_error_bank);
  81         }
  82         BUG_ON(len == -1);
  83
  84         return len;
  85 };
  86
  87 int apei_hest_parse(apei_hest_func_t func, void *data)
  88 {
  89         struct acpi_hest_header *hest_hdr;
  90         int i, rc, len;
  91
  92         if (hest_disable)
  93                 return -EINVAL;
  94
  95         hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
  96         for (i = 0; i < hest_tab->error_source_count; i++) {
  97                 len = hest_esrc_len(hest_hdr);
  98                 if (!len) {
  99                         pr_warning(FW_WARN HEST_PFX
 100                                    "Unknown or unused hardware error source "
 101                                    "type: %d for hardware error source: %d.\n",
 102                                    hest_hdr->type, hest_hdr->source_id);
 103                         return -EINVAL;
 104                 }
 105                 if ((void *)hest_hdr + len >
 106                     (void *)hest_tab + hest_tab->header.length) {
 107                         pr_warning(FW_BUG HEST_PFX
 108                 "Table contents overflow for hardware error source: %d.\n",
 109                                 hest_hdr->source_id);
 110                         return -EINVAL;
 111                 }
 112
 113                 rc = func(hest_hdr, data);
 114                 if (rc)
 115                         return rc;
 116
 117                 hest_hdr = (void *)hest_hdr + len;
 118         }
 119
 120         return 0;
 121 }
 122 EXPORT_SYMBOL_GPL(apei_hest_parse);
 123
 124 struct ghes_arr {
 125         struct platform_device **ghes_devs;
 126         unsigned int count;
 127 };
 128
 129 static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
 130 {
 131         int *count = data;
 132
 133         if (hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR)
 134                 (*count)++;
 135         return 0;
 136 }
 137
 138 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
 139 {
 140         struct platform_device *ghes_dev;
 141         struct ghes_arr *ghes_arr = data;
 142         int rc, i;
 143
 144         if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
 145                 return 0;
 146
 147         if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
 148                 return 0;
 149         for (i = 0; i < ghes_arr->count; i++) {
 150                 struct acpi_hest_header *hdr;
 151                 ghes_dev = ghes_arr->ghes_devs[i];
 152                 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
 153                 if (hdr->source_id == hest_hdr->source_id) {
 154                         pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
 155                                    hdr->source_id);
 156                         return -EIO;
 157                 }
 158         }
 159         ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
 160         if (!ghes_dev)
 161                 return -ENOMEM;
 162
 163         rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
 164         if (rc)
 165                 goto err;
 166
 167         rc = platform_device_add(ghes_dev);
 168         if (rc)
 169                 goto err;
 170         ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
 171
 172         return 0;
 173 err:
 174         platform_device_put(ghes_dev);
 175         return rc;
 176 }
 177
 178 static int __init hest_ghes_dev_register(unsigned int ghes_count)
 179 {
 180         int rc, i;
 181         struct ghes_arr ghes_arr;
 182
 183         ghes_arr.count = 0;
 184         ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL);
 185         if (!ghes_arr.ghes_devs)
 186                 return -ENOMEM;
 187
 188         rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
 189         if (rc)
 190                 goto err;
 191 out:
 192         kfree(ghes_arr.ghes_devs);
 193         return rc;
 194 err:
 195         for (i = 0; i < ghes_arr.count; i++)
 196                 platform_device_unregister(ghes_arr.ghes_devs[i]);
 197         goto out;
 198 }
 199
 200 static int __init setup_hest_disable(char *str)
 201 {
 202         hest_disable = 1;
 203         return 0;
 204 }
 205
 206 __setup("hest_disable", setup_hest_disable);
 207
 208 void __init acpi_hest_init(void)
 209 {
 210         acpi_status status;
 211         int rc = -ENODEV;
 212         unsigned int ghes_count = 0;
 213
 214         if (hest_disable) {
 215                 pr_info(HEST_PFX "Table parsing disabled.\n");
 216                 return;
 217         }
 218
 219         if (acpi_disabled)
 220                 goto err;
 221
 222         status = acpi_get_table(ACPI_SIG_HEST, 0,
 223                                 (struct acpi_table_header **)&hest_tab);
 224         if (status == AE_NOT_FOUND)
 225                 goto err;
 226         else if (ACPI_FAILURE(status)) {
 227                 const char *msg = acpi_format_exception(status);
 228                 pr_err(HEST_PFX "Failed to get table, %s\n", msg);
 229                 rc = -EINVAL;
 230                 goto err;
 231         }
 232
 233         if (!ghes_disable) {
 234                 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
 235                 if (rc)
 236                         goto err;
 237                 rc = hest_ghes_dev_register(ghes_count);
 238                 if (rc)
 239                         goto err;
 240         }
 241
 242         pr_info(HEST_PFX "Table parsing has been initialized.\n");
 243         return;
 244 err:
 245         hest_disable = 1;
 246 }