drivers/acpi/acpi_extlog.c

   1 /*
   2  * Extended Error Log driver
   3  *
   4  * Copyright (C) 2013 Intel Corp.
   5  * Author: Chen, Gong <gong.chen@intel.com>
   6  *
   7  * This file is licensed under GPLv2.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/acpi.h>
  12 #include <linux/cper.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/edac.h>
  15 #include <asm/cpu.h>
  16 #include <asm/mce.h>
  17
  18 #include "apei/apei-internal.h"
  19
  20 #define EXT_ELOG_ENTRY_MASK     GENMASK_ULL(51, 0) /* elog entry address mask */
  21
  22 #define EXTLOG_DSM_REV          0x0
  23 #define EXTLOG_FN_ADDR          0x1
  24
  25 #define FLAG_OS_OPTIN           BIT(0)
  26 #define ELOG_ENTRY_VALID        (1ULL<<63)
  27 #define ELOG_ENTRY_LEN          0x1000
  28
  29 #define EMCA_BUG \
  30         "Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n"
  31
  32 struct extlog_l1_head {
  33         u32 ver;        /* Header Version */
  34         u32 hdr_len;    /* Header Length */
  35         u64 total_len;  /* entire L1 Directory length including this header */
  36         u64 elog_base;  /* MCA Error Log Directory base address */
  37         u64 elog_len;   /* MCA Error Log Directory length */
  38         u32 flags;      /* bit 0 - OS/VMM Opt-in */
  39         u8  rev0[12];
  40         u32 entries;    /* Valid L1 Directory entries per logical processor */
  41         u8  rev1[12];
  42 };
  43
  44 static int old_edac_report_status;
  45
  46 static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295";
  47
  48 /* L1 table related physical address */
  49 static u64 elog_base;
  50 static size_t elog_size;
  51 static u64 l1_dirbase;
  52 static size_t l1_size;
  53
  54 /* L1 table related virtual address */
  55 static void __iomem *extlog_l1_addr;
  56 static void __iomem *elog_addr;
  57
  58 static void *elog_buf;
  59
  60 static u64 *l1_entry_base;
  61 static u32 l1_percpu_entry;
  62
  63 #define ELOG_IDX(cpu, bank) \
  64         (cpu_physical_id(cpu) * l1_percpu_entry + (bank))
  65
  66 #define ELOG_ENTRY_DATA(idx) \
  67         (*(l1_entry_base + (idx)))
  68
  69 #define ELOG_ENTRY_ADDR(phyaddr) \
  70         (phyaddr - elog_base + (u8 *)elog_addr)
  71
  72 static struct acpi_generic_status *extlog_elog_entry_check(int cpu, int bank)
  73 {
  74         int idx;
  75         u64 data;
  76         struct acpi_generic_status *estatus;
  77
  78         WARN_ON(cpu < 0);
  79         idx = ELOG_IDX(cpu, bank);
  80         data = ELOG_ENTRY_DATA(idx);
  81         if ((data & ELOG_ENTRY_VALID) == 0)
  82                 return NULL;
  83
  84         data &= EXT_ELOG_ENTRY_MASK;
  85         estatus = (struct acpi_generic_status *)ELOG_ENTRY_ADDR(data);
  86
  87         /* if no valid data in elog entry, just return */
  88         if (estatus->block_status == 0)
  89                 return NULL;
  90
  91         return estatus;
  92 }
  93
  94 static void __print_extlog_rcd(const char *pfx,
  95                                struct acpi_generic_status *estatus, int cpu)
  96 {
  97         static atomic_t seqno;
  98         unsigned int curr_seqno;
  99         char pfx_seq[64];
 100
 101         if (!pfx) {
 102                 if (estatus->error_severity <= CPER_SEV_CORRECTED)
 103                         pfx = KERN_INFO;
 104                 else
 105                         pfx = KERN_ERR;
 106         }
 107         curr_seqno = atomic_inc_return(&seqno);
 108         snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno);
 109         printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu);
 110         cper_estatus_print(pfx_seq, estatus);
 111 }
 112
 113 static int print_extlog_rcd(const char *pfx,
 114                             struct acpi_generic_status *estatus, int cpu)
 115 {
 116         /* Not more than 2 messages every 5 seconds */
 117         static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 118         static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 119         struct ratelimit_state *ratelimit;
 120
 121         if (estatus->error_severity == CPER_SEV_CORRECTED ||
 122             (estatus->error_severity == CPER_SEV_INFORMATIONAL))
 123                 ratelimit = &ratelimit_corrected;
 124         else
 125                 ratelimit = &ratelimit_uncorrected;
 126         if (__ratelimit(ratelimit)) {
 127                 __print_extlog_rcd(pfx, estatus, cpu);
 128                 return 0;
 129         }
 130
 131         return 1;
 132 }
 133
 134 static int extlog_print(struct notifier_block *nb, unsigned long val,
 135                         void *data)
 136 {
 137         struct mce *mce = (struct mce *)data;
 138         int     bank = mce->bank;
 139         int     cpu = mce->extcpu;
 140         struct acpi_generic_status *estatus;
 141         int rc;
 142
 143         estatus = extlog_elog_entry_check(cpu, bank);
 144         if (estatus == NULL)
 145                 return NOTIFY_DONE;
 146
 147         memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN);
 148         /* clear record status to enable BIOS to update it again */
 149         estatus->block_status = 0;
 150
 151         rc = print_extlog_rcd(NULL, (struct acpi_generic_status *)elog_buf, cpu);
 152
 153         return NOTIFY_STOP;
 154 }
 155
 156 static bool __init extlog_get_l1addr(void)
 157 {
 158         u8 uuid[16];
 159         acpi_handle handle;
 160         union acpi_object *obj;
 161
 162         acpi_str_to_uuid(extlog_dsm_uuid, uuid);
 163
 164         if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
 165                 return false;
 166         if (!acpi_check_dsm(handle, uuid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR))
 167                 return false;
 168         obj = acpi_evaluate_dsm_typed(handle, uuid, EXTLOG_DSM_REV,
 169                                       EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER);
 170         if (!obj) {
 171                 return false;
 172         } else {
 173                 l1_dirbase = obj->integer.value;
 174                 ACPI_FREE(obj);
 175         }
 176
 177         /* Spec says L1 directory must be 4K aligned, bail out if it isn't */
 178         if (l1_dirbase & ((1 << 12) - 1)) {
 179                 pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n",
 180                         l1_dirbase);
 181                 return false;
 182         }
 183
 184         return true;
 185 }
 186 static struct notifier_block extlog_mce_dec = {
 187         .notifier_call  = extlog_print,
 188 };
 189
 190 static int __init extlog_init(void)
 191 {
 192         struct extlog_l1_head *l1_head;
 193         void __iomem *extlog_l1_hdr;
 194         size_t l1_hdr_size;
 195         struct resource *r;
 196         u64 cap;
 197         int rc;
 198
 199         if (get_edac_report_status() == EDAC_REPORTING_FORCE) {
 200                 pr_warn("Not loading eMCA, error reporting force-enabled through EDAC.\n");
 201                 return -EPERM;
 202         }
 203
 204         rc = -ENODEV;
 205         rdmsrl(MSR_IA32_MCG_CAP, cap);
 206         if (!(cap & MCG_ELOG_P))
 207                 return rc;
 208
 209         if (!extlog_get_l1addr())
 210                 return rc;
 211
 212         rc = -EINVAL;
 213         /* get L1 header to fetch necessary information */
 214         l1_hdr_size = sizeof(struct extlog_l1_head);
 215         r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR");
 216         if (!r) {
 217                 pr_warn(FW_BUG EMCA_BUG,
 218                         (unsigned long long)l1_dirbase,
 219                         (unsigned long long)l1_dirbase + l1_hdr_size);
 220                 goto err;
 221         }
 222
 223         extlog_l1_hdr = acpi_os_map_memory(l1_dirbase, l1_hdr_size);
 224         l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
 225         l1_size = l1_head->total_len;
 226         l1_percpu_entry = l1_head->entries;
 227         elog_base = l1_head->elog_base;
 228         elog_size = l1_head->elog_len;
 229         acpi_os_unmap_memory(extlog_l1_hdr, l1_hdr_size);
 230         release_mem_region(l1_dirbase, l1_hdr_size);
 231
 232         /* remap L1 header again based on completed information */
 233         r = request_mem_region(l1_dirbase, l1_size, "L1 Table");
 234         if (!r) {
 235                 pr_warn(FW_BUG EMCA_BUG,
 236                         (unsigned long long)l1_dirbase,
 237                         (unsigned long long)l1_dirbase + l1_size);
 238                 goto err;
 239         }
 240         extlog_l1_addr = acpi_os_map_memory(l1_dirbase, l1_size);
 241         l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
 242
 243         /* remap elog table */
 244         r = request_mem_region(elog_base, elog_size, "Elog Table");
 245         if (!r) {
 246                 pr_warn(FW_BUG EMCA_BUG,
 247                         (unsigned long long)elog_base,
 248                         (unsigned long long)elog_base + elog_size);
 249                 goto err_release_l1_dir;
 250         }
 251         elog_addr = acpi_os_map_memory(elog_base, elog_size);
 252
 253         rc = -ENOMEM;
 254         /* allocate buffer to save elog record */
 255         elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL);
 256         if (elog_buf == NULL)
 257                 goto err_release_elog;
 258
 259         /*
 260          * eMCA event report method has higher priority than EDAC method,
 261          * unless EDAC event report method is mandatory.
 262          */
 263         old_edac_report_status = get_edac_report_status();
 264         set_edac_report_status(EDAC_REPORTING_DISABLED);
 265         mce_register_decode_chain(&extlog_mce_dec);
 266         /* enable OS to be involved to take over management from BIOS */
 267         ((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN;
 268
 269         return 0;
 270
 271 err_release_elog:
 272         if (elog_addr)
 273                 acpi_os_unmap_memory(elog_addr, elog_size);
 274         release_mem_region(elog_base, elog_size);
 275 err_release_l1_dir:
 276         if (extlog_l1_addr)
 277                 acpi_os_unmap_memory(extlog_l1_addr, l1_size);
 278         release_mem_region(l1_dirbase, l1_size);
 279 err:
 280         pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
 281         return rc;
 282 }
 283
 284 static void __exit extlog_exit(void)
 285 {
 286         set_edac_report_status(old_edac_report_status);
 287         mce_unregister_decode_chain(&extlog_mce_dec);
 288         ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
 289         if (extlog_l1_addr)
 290                 acpi_os_unmap_memory(extlog_l1_addr, l1_size);
 291         if (elog_addr)
 292                 acpi_os_unmap_memory(elog_addr, elog_size);
 293         release_mem_region(elog_base, elog_size);
 294         release_mem_region(l1_dirbase, l1_size);
 295         kfree(elog_buf);
 296 }
 297
 298 module_init(extlog_init);
 299 module_exit(extlog_exit);
 300
 301 MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>");
 302 MODULE_DESCRIPTION("Extended MCA Error Log Driver");
 303 MODULE_LICENSE("GPL");