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 <acpi/apei.h>
  38
  39 #include "apei-internal.h"
  40
  41 #define HEST_PFX "HEST: "
  42
  43 int hest_disable;
  44 EXPORT_SYMBOL_GPL(hest_disable);
  45
  46 /* HEST table parsing */
  47
  48 static struct acpi_table_hest *hest_tab;
  49
  50 static int hest_void_parse(struct acpi_hest_header *hest_hdr, void *data)
  51 {
  52         return 0;
  53 }
  54
  55 static int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
  56         [ACPI_HEST_TYPE_IA32_CHECK] = -1,       /* need further calculation */
  57         [ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
  58         [ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
  59         [ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
  60         [ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
  61         [ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
  62         [ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
  63 };
  64
  65 static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
  66 {
  67         u16 hest_type = hest_hdr->type;
  68         int len;
  69
  70         if (hest_type >= ACPI_HEST_TYPE_RESERVED)
  71                 return 0;
  72
  73         len = hest_esrc_len_tab[hest_type];
  74
  75         if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
  76                 struct acpi_hest_ia_corrected *cmc;
  77                 cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
  78                 len = sizeof(*cmc) + cmc->num_hardware_banks *
  79                         sizeof(struct acpi_hest_ia_error_bank);
  80         } else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
  81                 struct acpi_hest_ia_machine_check *mc;
  82                 mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
  83                 len = sizeof(*mc) + mc->num_hardware_banks *
  84                         sizeof(struct acpi_hest_ia_error_bank);
  85         }
  86         BUG_ON(len == -1);
  87
  88         return len;
  89 };
  90
  91 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)
  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_warning(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_warning(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 EXPORT_SYMBOL_GPL(apei_hest_parse);
 127
 128 static int __init setup_hest_disable(char *str)
 129 {
 130         hest_disable = 1;
 131         return 0;
 132 }
 133
 134 __setup("hest_disable", setup_hest_disable);
 135
 136 static int __init hest_init(void)
 137 {
 138         acpi_status status;
 139         int rc = -ENODEV;
 140
 141         if (acpi_disabled)
 142                 goto err;
 143
 144         if (hest_disable) {
 145                 pr_info(HEST_PFX "HEST tabling parsing is disabled.\n");
 146                 goto err;
 147         }
 148
 149         status = acpi_get_table(ACPI_SIG_HEST, 0,
 150                                 (struct acpi_table_header **)&hest_tab);
 151         if (status == AE_NOT_FOUND) {
 152                 pr_info(HEST_PFX "Table is not found!\n");
 153                 goto err;
 154         } else if (ACPI_FAILURE(status)) {
 155                 const char *msg = acpi_format_exception(status);
 156                 pr_err(HEST_PFX "Failed to get table, %s\n", msg);
 157                 rc = -EINVAL;
 158                 goto err;
 159         }
 160
 161         rc = apei_hest_parse(hest_void_parse, NULL);
 162         if (rc)
 163                 goto err;
 164
 165         pr_info(HEST_PFX "HEST table parsing is initialized.\n");
 166
 167         return 0;
 168 err:
 169         hest_disable = 1;
 170         return rc;
 171 }
 172
 173 subsys_initcall(hest_init);