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 <linux/ras.h>
  16 #include <asm/cpu.h>
  17 #include <asm/mce.h>
  18
  19 #include "apei/apei-internal.h"
  20 #include <ras/ras_event.h>
  21
  22 #define EXT_ELOG_ENTRY_MASK     GENMASK_ULL(51, 0) /* elog entry address mask */
  23
  24 #define EXTLOG_DSM_REV          0x0
  25 #define EXTLOG_FN_ADDR          0x1
  26
  27 #define FLAG_OS_OPTIN           BIT(0)
  28 #define ELOG_ENTRY_VALID        (1ULL<<63)
  29 #define ELOG_ENTRY_LEN          0x1000
  30
  31 #define EMCA_BUG \
  32         "Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n"
  33
  34 struct extlog_l1_head {
  35         u32 ver;        /* Header Version */
  36         u32 hdr_len;    /* Header Length */
  37         u64 total_len;  /* entire L1 Directory length including this header */
  38         u64 elog_base;  /* MCA Error Log Directory base address */
  39         u64 elog_len;   /* MCA Error Log Directory length */
  40         u32 flags;      /* bit 0 - OS/VMM Opt-in */
  41         u8  rev0[12];
  42         u32 entries;    /* Valid L1 Directory entries per logical processor */
  43         u8  rev1[12];
  44 };
  45
  46 static int old_edac_report_status;
  47
  48 static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295";
  49
  50 /* L1 table related physical address */
  51 static u64 elog_base;
  52 static size_t elog_size;
  53 static u64 l1_dirbase;
  54 static size_t l1_size;
  55
  56 /* L1 table related virtual address */
  57 static void __iomem *extlog_l1_addr;
  58 static void __iomem *elog_addr;
  59
  60 static void *elog_buf;
  61
  62 static u64 *l1_entry_base;
  63 static u32 l1_percpu_entry;
  64
  65 #define ELOG_IDX(cpu, bank) \
  66         (cpu_physical_id(cpu) * l1_percpu_entry + (bank))
  67
  68 #define ELOG_ENTRY_DATA(idx) \
  69         (*(l1_entry_base + (idx)))
  70
  71 #define ELOG_ENTRY_ADDR(phyaddr) \
  72         (phyaddr - elog_base + (u8 *)elog_addr)
  73
  74 static struct acpi_hest_generic_status *extlog_elog_entry_check(int cpu, int bank)
  75 {
  76         int idx;
  77         u64 data;
  78         struct acpi_hest_generic_status *estatus;
  79
  80         WARN_ON(cpu < 0);
  81         idx = ELOG_IDX(cpu, bank);
  82         data = ELOG_ENTRY_DATA(idx);
  83         if ((data & ELOG_ENTRY_VALID) == 0)
  84                 return NULL;
  85
  86         data &= EXT_ELOG_ENTRY_MASK;
  87         estatus = (struct acpi_hest_generic_status *)ELOG_ENTRY_ADDR(data);
  88
  89         /* if no valid data in elog entry, just return */
  90         if (estatus->block_status == 0)
  91                 return NULL;
  92
  93         return estatus;
  94 }
  95
  96 static void __print_extlog_rcd(const char *pfx,
  97                                struct acpi_hest_generic_status *estatus, int cpu)
  98 {
  99         static atomic_t seqno;
 100         unsigned int curr_seqno;
 101         char pfx_seq[64];
 102
 103         if (!pfx) {
 104                 if (estatus->error_severity <= CPER_SEV_CORRECTED)
 105                         pfx = KERN_INFO;
 106                 else
 107                         pfx = KERN_ERR;
 108         }
 109         curr_seqno = atomic_inc_return(&seqno);
 110         snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno);
 111         printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu);
 112         cper_estatus_print(pfx_seq, estatus);
 113 }
 114
 115 static int print_extlog_rcd(const char *pfx,
 116                             struct acpi_hest_generic_status *estatus, int cpu)
 117 {
 118         /* Not more than 2 messages every 5 seconds */
 119         static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 120         static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 121         struct ratelimit_state *ratelimit;
 122
 123         if (estatus->error_severity == CPER_SEV_CORRECTED ||
 124             (estatus->error_severity == CPER_SEV_INFORMATIONAL))
 125                 ratelimit = &ratelimit_corrected;
 126         else
 127                 ratelimit = &ratelimit_uncorrected;
 128         if (__ratelimit(ratelimit)) {
 129                 __print_extlog_rcd(pfx, estatus, cpu);
 130                 return 0;
 131         }
 132
 133         return 1;
 134 }
 135
 136 static int extlog_print(struct notifier_block *nb, unsigned long val,
 137                         void *data)
 138 {
 139         struct mce *mce = (struct mce *)data;
 140         int     bank = mce->bank;
 141         int     cpu = mce->extcpu;
 142         struct acpi_hest_generic_status *estatus, *tmp;
 143         struct acpi_hest_generic_data *gdata;
 144         const guid_t *fru_id = &guid_null;
 145         char *fru_text = "";
 146         guid_t *sec_type;
 147         static u32 err_seq;
 148
 149         estatus = extlog_elog_entry_check(cpu, bank);
 150         if (estatus == NULL)
 151                 return NOTIFY_DONE;
 152
 153         memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN);
 154         /* clear record status to enable BIOS to update it again */
 155         estatus->block_status = 0;
 156
 157         tmp = (struct acpi_hest_generic_status *)elog_buf;
 158
 159         if (!ras_userspace_consumers()) {
 160                 print_extlog_rcd(NULL, tmp, cpu);
 161                 goto out;
 162         }
 163
 164         /* log event via trace */
 165         err_seq++;
 166         gdata = (struct acpi_hest_generic_data *)(tmp + 1);
 167         if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
 168                 fru_id = (guid_t *)gdata->fru_id;
 169         if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
 170                 fru_text = gdata->fru_text;
 171         sec_type = (guid_t *)gdata->section_type;
 172         if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
 173                 struct cper_sec_mem_err *mem = (void *)(gdata + 1);
 174                 if (gdata->error_data_length >= sizeof(*mem))
 175                         trace_extlog_mem_event(mem, err_seq, fru_id, fru_text,
 176                                                (u8)gdata->error_severity);
 177         }
 178
 179 out:
 180         return NOTIFY_STOP;
 181 }
 182
 183 static bool __init extlog_get_l1addr(void)
 184 {
 185         guid_t guid;
 186         acpi_handle handle;
 187         union acpi_object *obj;
 188
 189         if (guid_parse(extlog_dsm_uuid, &guid))
 190                 return false;
 191         if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
 192                 return false;
 193         if (!acpi_check_dsm(handle, &guid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR))
 194                 return false;
 195         obj = acpi_evaluate_dsm_typed(handle, &guid, EXTLOG_DSM_REV,
 196                                       EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER);
 197         if (!obj) {
 198                 return false;
 199         } else {
 200                 l1_dirbase = obj->integer.value;
 201                 ACPI_FREE(obj);
 202         }
 203
 204         /* Spec says L1 directory must be 4K aligned, bail out if it isn't */
 205         if (l1_dirbase & ((1 << 12) - 1)) {
 206                 pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n",
 207                         l1_dirbase);
 208                 return false;
 209         }
 210
 211         return true;
 212 }
 213 static struct notifier_block extlog_mce_dec = {
 214         .notifier_call  = extlog_print,
 215         .priority       = MCE_PRIO_EXTLOG,
 216 };
 217
 218 static int __init extlog_init(void)
 219 {
 220         struct extlog_l1_head *l1_head;
 221         void __iomem *extlog_l1_hdr;
 222         size_t l1_hdr_size;
 223         struct resource *r;
 224         u64 cap;
 225         int rc;
 226
 227         rdmsrl(MSR_IA32_MCG_CAP, cap);
 228
 229         if (!(cap & MCG_ELOG_P) || !extlog_get_l1addr())
 230                 return -ENODEV;
 231
 232         if (edac_get_report_status() == EDAC_REPORTING_FORCE) {
 233                 pr_warn("Not loading eMCA, error reporting force-enabled through EDAC.\n");
 234                 return -EPERM;
 235         }
 236
 237         rc = -EINVAL;
 238         /* get L1 header to fetch necessary information */
 239         l1_hdr_size = sizeof(struct extlog_l1_head);
 240         r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR");
 241         if (!r) {
 242                 pr_warn(FW_BUG EMCA_BUG,
 243                         (unsigned long long)l1_dirbase,
 244                         (unsigned long long)l1_dirbase + l1_hdr_size);
 245                 goto err;
 246         }
 247
 248         extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size);
 249         l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
 250         l1_size = l1_head->total_len;
 251         l1_percpu_entry = l1_head->entries;
 252         elog_base = l1_head->elog_base;
 253         elog_size = l1_head->elog_len;
 254         acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size);
 255         release_mem_region(l1_dirbase, l1_hdr_size);
 256
 257         /* remap L1 header again based on completed information */
 258         r = request_mem_region(l1_dirbase, l1_size, "L1 Table");
 259         if (!r) {
 260                 pr_warn(FW_BUG EMCA_BUG,
 261                         (unsigned long long)l1_dirbase,
 262                         (unsigned long long)l1_dirbase + l1_size);
 263                 goto err;
 264         }
 265         extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size);
 266         l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
 267
 268         /* remap elog table */
 269         r = request_mem_region(elog_base, elog_size, "Elog Table");
 270         if (!r) {
 271                 pr_warn(FW_BUG EMCA_BUG,
 272                         (unsigned long long)elog_base,
 273                         (unsigned long long)elog_base + elog_size);
 274                 goto err_release_l1_dir;
 275         }
 276         elog_addr = acpi_os_map_iomem(elog_base, elog_size);
 277
 278         rc = -ENOMEM;
 279         /* allocate buffer to save elog record */
 280         elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL);
 281         if (elog_buf == NULL)
 282                 goto err_release_elog;
 283
 284         /*
 285          * eMCA event report method has higher priority than EDAC method,
 286          * unless EDAC event report method is mandatory.
 287          */
 288         old_edac_report_status = edac_get_report_status();
 289         edac_set_report_status(EDAC_REPORTING_DISABLED);
 290         mce_register_decode_chain(&extlog_mce_dec);
 291         /* enable OS to be involved to take over management from BIOS */
 292         ((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN;
 293
 294         return 0;
 295
 296 err_release_elog:
 297         if (elog_addr)
 298                 acpi_os_unmap_iomem(elog_addr, elog_size);
 299         release_mem_region(elog_base, elog_size);
 300 err_release_l1_dir:
 301         if (extlog_l1_addr)
 302                 acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
 303         release_mem_region(l1_dirbase, l1_size);
 304 err:
 305         pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
 306         return rc;
 307 }
 308
 309 static void __exit extlog_exit(void)
 310 {
 311         edac_set_report_status(old_edac_report_status);
 312         mce_unregister_decode_chain(&extlog_mce_dec);
 313         ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
 314         if (extlog_l1_addr)
 315                 acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
 316         if (elog_addr)
 317                 acpi_os_unmap_iomem(elog_addr, elog_size);
 318         release_mem_region(elog_base, elog_size);
 319         release_mem_region(l1_dirbase, l1_size);
 320         kfree(elog_buf);
 321 }
 322
 323 module_init(extlog_init);
 324 module_exit(extlog_exit);
 325
 326 MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>");
 327 MODULE_DESCRIPTION("Extended MCA Error Log Driver");
 328 MODULE_LICENSE("GPL");