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 bool 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 };
  56
  57 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
  58 {
  59         u16 hest_type = hest_hdr->type;
  60         int len;
  61
  62         if (hest_type >= ACPI_HEST_TYPE_RESERVED)
  63                 return 0;
  64
  65         len = hest_esrc_len_tab[hest_type];
  66
  67         if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
  68                 struct acpi_hest_ia_corrected *cmc;
  69                 cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
  70                 len = sizeof(*cmc) + cmc->num_hardware_banks *
  71                         sizeof(struct acpi_hest_ia_error_bank);
  72         } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
  73                 struct acpi_hest_ia_machine_check *mc;
  74                 mc = (struct acpi_hest_ia_machine_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_warning(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_warning(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                 (*count)++;
 146         return 0;
 147 }
 148
 149 static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
 150 {
 151         struct platform_device *ghes_dev;
 152         struct ghes_arr *ghes_arr = data;
 153         int rc, i;
 154
 155         if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR)
 156                 return 0;
 157
 158         if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
 159                 return 0;
 160         for (i = 0; i < ghes_arr->count; i++) {
 161                 struct acpi_hest_header *hdr;
 162                 ghes_dev = ghes_arr->ghes_devs[i];
 163                 hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
 164                 if (hdr->source_id == hest_hdr->source_id) {
 165                         pr_warning(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
 166                                    hdr->source_id);
 167                         return -EIO;
 168                 }
 169         }
 170         ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
 171         if (!ghes_dev)
 172                 return -ENOMEM;
 173
 174         rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
 175         if (rc)
 176                 goto err;
 177
 178         rc = platform_device_add(ghes_dev);
 179         if (rc)
 180                 goto err;
 181         ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
 182
 183         return 0;
 184 err:
 185         platform_device_put(ghes_dev);
 186         return rc;
 187 }
 188
 189 static int __init hest_ghes_dev_register(unsigned int ghes_count)
 190 {
 191         int rc, i;
 192         struct ghes_arr ghes_arr;
 193
 194         ghes_arr.count = 0;
 195         ghes_arr.ghes_devs = kmalloc(sizeof(void *) * ghes_count, GFP_KERNEL);
 196         if (!ghes_arr.ghes_devs)
 197                 return -ENOMEM;
 198
 199         rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
 200         if (rc)
 201                 goto err;
 202 out:
 203         kfree(ghes_arr.ghes_devs);
 204         return rc;
 205 err:
 206         for (i = 0; i < ghes_arr.count; i++)
 207                 platform_device_unregister(ghes_arr.ghes_devs[i]);
 208         goto out;
 209 }
 210
 211 static int __init setup_hest_disable(char *str)
 212 {
 213         hest_disable = 1;
 214         return 0;
 215 }
 216
 217 __setup("hest_disable", setup_hest_disable);
 218
 219 void __init acpi_hest_init(void)
 220 {
 221         acpi_status status;
 222         int rc = -ENODEV;
 223         unsigned int ghes_count = 0;
 224
 225         if (hest_disable) {
 226                 pr_info(HEST_PFX "Table parsing disabled.\n");
 227                 return;
 228         }
 229
 230         status = acpi_get_table(ACPI_SIG_HEST, 0,
 231                                 (struct acpi_table_header **)&hest_tab);
 232         if (status == AE_NOT_FOUND)
 233                 goto err;
 234         else if (ACPI_FAILURE(status)) {
 235                 const char *msg = acpi_format_exception(status);
 236                 pr_err(HEST_PFX "Failed to get table, %s\n", msg);
 237                 rc = -EINVAL;
 238                 goto err;
 239         }
 240
 241         rc = apei_hest_parse(hest_parse_cmc, NULL);
 242         if (rc)
 243                 goto err;
 244
 245         if (!ghes_disable) {
 246                 rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
 247                 if (rc)
 248                         goto err;
 249                 rc = hest_ghes_dev_register(ghes_count);
 250                 if (rc)
 251                         goto err;
 252         }
 253
 254         pr_info(HEST_PFX "Table parsing has been initialized.\n");
 255         return;
 256 err:
 257         hest_disable = 1;
 258 }