drivers/acpi/acpi_extlog.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Extended Error Log driver
   4  *
   5  * Copyright (C) 2013 Intel Corp.
   6  * Author: Chen, Gong <gong.chen@intel.com>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/acpi.h>
  11 #include <linux/cper.h>
  12 #include <linux/ratelimit.h>
  13 #include <linux/edac.h>
  14 #include <linux/ras.h>
  15 #include <asm/cpu.h>
  16 #include <asm/mce.h>
  17
  18 #include "apei/apei-internal.h"
  19 #include <ras/ras_event.h>
  20
  21 #define EXT_ELOG_ENTRY_MASK     GENMASK_ULL(51, 0) /* elog entry address mask */
  22
  23 #define EXTLOG_DSM_REV          0x0
  24 #define EXTLOG_FN_ADDR          0x1
  25
  26 #define FLAG_OS_OPTIN           BIT(0)
  27 #define ELOG_ENTRY_VALID        (1ULL<<63)
  28 #define ELOG_ENTRY_LEN          0x1000
  29
  30 #define EMCA_BUG \
  31         "Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n"
  32
  33 struct extlog_l1_head {
  34         u32 ver;        /* Header Version */
  35         u32 hdr_len;    /* Header Length */
  36         u64 total_len;  /* entire L1 Directory length including this header */
  37         u64 elog_base;  /* MCA Error Log Directory base address */
  38         u64 elog_len;   /* MCA Error Log Directory length */
  39         u32 flags;      /* bit 0 - OS/VMM Opt-in */
  40         u8  rev0[12];
  41         u32 entries;    /* Valid L1 Directory entries per logical processor */
  42         u8  rev1[12];
  43 };
  44
  45 static int old_edac_report_status;
  46
  47 static u8 extlog_dsm_uuid[] __initdata = "663E35AF-CC10-41A4-88EA-5470AF055295";
  48
  49 /* L1 table related physical address */
  50 static u64 elog_base;
  51 static size_t elog_size;
  52 static u64 l1_dirbase;
  53 static size_t l1_size;
  54
  55 /* L1 table related virtual address */
  56 static void __iomem *extlog_l1_addr;
  57 static void __iomem *elog_addr;
  58
  59 static void *elog_buf;
  60
  61 static u64 *l1_entry_base;
  62 static u32 l1_percpu_entry;
  63
  64 #define ELOG_IDX(cpu, bank) \
  65         (cpu_physical_id(cpu) * l1_percpu_entry + (bank))
  66
  67 #define ELOG_ENTRY_DATA(idx) \
  68         (*(l1_entry_base + (idx)))
  69
  70 #define ELOG_ENTRY_ADDR(phyaddr) \
  71         (phyaddr - elog_base + (u8 *)elog_addr)
  72
  73 static struct acpi_hest_generic_status *extlog_elog_entry_check(int cpu, int bank)
  74 {
  75         int idx;
  76         u64 data;
  77         struct acpi_hest_generic_status *estatus;
  78
  79         WARN_ON(cpu < 0);
  80         idx = ELOG_IDX(cpu, bank);
  81         data = ELOG_ENTRY_DATA(idx);
  82         if ((data & ELOG_ENTRY_VALID) == 0)
  83                 return NULL;
  84
  85         data &= EXT_ELOG_ENTRY_MASK;
  86         estatus = (struct acpi_hest_generic_status *)ELOG_ENTRY_ADDR(data);
  87
  88         /* if no valid data in elog entry, just return */
  89         if (estatus->block_status == 0)
  90                 return NULL;
  91
  92         return estatus;
  93 }
  94
  95 static void __print_extlog_rcd(const char *pfx,
  96                                struct acpi_hest_generic_status *estatus, int cpu)
  97 {
  98         static atomic_t seqno;
  99         unsigned int curr_seqno;
 100         char pfx_seq[64];
 101
 102         if (!pfx) {
 103                 if (estatus->error_severity <= CPER_SEV_CORRECTED)
 104                         pfx = KERN_INFO;
 105                 else
 106                         pfx = KERN_ERR;
 107         }
 108         curr_seqno = atomic_inc_return(&seqno);
 109         snprintf(pfx_seq, sizeof(pfx_seq), "%s{%u}", pfx, curr_seqno);
 110         printk("%s""Hardware error detected on CPU%d\n", pfx_seq, cpu);
 111         cper_estatus_print(pfx_seq, estatus);
 112 }
 113
 114 static int print_extlog_rcd(const char *pfx,
 115                             struct acpi_hest_generic_status *estatus, int cpu)
 116 {
 117         /* Not more than 2 messages every 5 seconds */
 118         static DEFINE_RATELIMIT_STATE(ratelimit_corrected, 5*HZ, 2);
 119         static DEFINE_RATELIMIT_STATE(ratelimit_uncorrected, 5*HZ, 2);
 120         struct ratelimit_state *ratelimit;
 121
 122         if (estatus->error_severity == CPER_SEV_CORRECTED ||
 123             (estatus->error_severity == CPER_SEV_INFORMATIONAL))
 124                 ratelimit = &ratelimit_corrected;
 125         else
 126                 ratelimit = &ratelimit_uncorrected;
 127         if (__ratelimit(ratelimit)) {
 128                 __print_extlog_rcd(pfx, estatus, cpu);
 129                 return 0;
 130         }
 131
 132         return 1;
 133 }
 134
 135 static int extlog_print(struct notifier_block *nb, unsigned long val,
 136                         void *data)
 137 {
 138         struct mce *mce = (struct mce *)data;
 139         int     bank = mce->bank;
 140         int     cpu = mce->extcpu;
 141         struct acpi_hest_generic_status *estatus, *tmp;
 142         struct acpi_hest_generic_data *gdata;
 143         const guid_t *fru_id = &guid_null;
 144         char *fru_text = "";
 145         guid_t *sec_type;
 146         static u32 err_seq;
 147
 148         estatus = extlog_elog_entry_check(cpu, bank);
 149         if (estatus == NULL)
 150                 return NOTIFY_DONE;
 151
 152         memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN);
 153         /* clear record status to enable BIOS to update it again */
 154         estatus->block_status = 0;
 155
 156         tmp = (struct acpi_hest_generic_status *)elog_buf;
 157
 158         if (!ras_userspace_consumers()) {
 159                 print_extlog_rcd(NULL, tmp, cpu);
 160                 goto out;
 161         }
 162
 163         /* log event via trace */
 164         err_seq++;
 165         gdata = (struct acpi_hest_generic_data *)(tmp + 1);
 166         if (gdata->validation_bits & CPER_SEC_VALID_FRU_ID)
 167                 fru_id = (guid_t *)gdata->fru_id;
 168         if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT)
 169                 fru_text = gdata->fru_text;
 170         sec_type = (guid_t *)gdata->section_type;
 171         if (guid_equal(sec_type, &CPER_SEC_PLATFORM_MEM)) {
 172                 struct cper_sec_mem_err *mem = (void *)(gdata + 1);
 173                 if (gdata->error_data_length >= sizeof(*mem))
 174                         trace_extlog_mem_event(mem, err_seq, fru_id, fru_text,
 175                                                (u8)gdata->error_severity);
 176         }
 177
 178 out:
 179         return NOTIFY_STOP;
 180 }
 181
 182 static bool __init extlog_get_l1addr(void)
 183 {
 184         guid_t guid;
 185         acpi_handle handle;
 186         union acpi_object *obj;
 187
 188         if (guid_parse(extlog_dsm_uuid, &guid))
 189                 return false;
 190         if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
 191                 return false;
 192         if (!acpi_check_dsm(handle, &guid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR))
 193                 return false;
 194         obj = acpi_evaluate_dsm_typed(handle, &guid, EXTLOG_DSM_REV,
 195                                       EXTLOG_FN_ADDR, NULL, ACPI_TYPE_INTEGER);
 196         if (!obj) {
 197                 return false;
 198         } else {
 199                 l1_dirbase = obj->integer.value;
 200                 ACPI_FREE(obj);
 201         }
 202
 203         /* Spec says L1 directory must be 4K aligned, bail out if it isn't */
 204         if (l1_dirbase & ((1 << 12) - 1)) {
 205                 pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n",
 206                         l1_dirbase);
 207                 return false;
 208         }
 209
 210         return true;
 211 }
 212 static struct notifier_block extlog_mce_dec = {
 213         .notifier_call  = extlog_print,
 214         .priority       = MCE_PRIO_EXTLOG,
 215 };
 216
 217 static int __init extlog_init(void)
 218 {
 219         struct extlog_l1_head *l1_head;
 220         void __iomem *extlog_l1_hdr;
 221         size_t l1_hdr_size;
 222         struct resource *r;
 223         u64 cap;
 224         int rc;
 225
 226         rdmsrl(MSR_IA32_MCG_CAP, cap);
 227
 228         if (!(cap & MCG_ELOG_P) || !extlog_get_l1addr())
 229                 return -ENODEV;
 230
 231         if (edac_get_report_status() == EDAC_REPORTING_FORCE) {
 232                 pr_warn("Not loading eMCA, error reporting force-enabled through EDAC.\n");
 233                 return -EPERM;
 234         }
 235
 236         rc = -EINVAL;
 237         /* get L1 header to fetch necessary information */
 238         l1_hdr_size = sizeof(struct extlog_l1_head);
 239         r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR");
 240         if (!r) {
 241                 pr_warn(FW_BUG EMCA_BUG,
 242                         (unsigned long long)l1_dirbase,
 243                         (unsigned long long)l1_dirbase + l1_hdr_size);
 244                 goto err;
 245         }
 246
 247         extlog_l1_hdr = acpi_os_map_iomem(l1_dirbase, l1_hdr_size);
 248         l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
 249         l1_size = l1_head->total_len;
 250         l1_percpu_entry = l1_head->entries;
 251         elog_base = l1_head->elog_base;
 252         elog_size = l1_head->elog_len;
 253         acpi_os_unmap_iomem(extlog_l1_hdr, l1_hdr_size);
 254         release_mem_region(l1_dirbase, l1_hdr_size);
 255
 256         /* remap L1 header again based on completed information */
 257         r = request_mem_region(l1_dirbase, l1_size, "L1 Table");
 258         if (!r) {
 259                 pr_warn(FW_BUG EMCA_BUG,
 260                         (unsigned long long)l1_dirbase,
 261                         (unsigned long long)l1_dirbase + l1_size);
 262                 goto err;
 263         }
 264         extlog_l1_addr = acpi_os_map_iomem(l1_dirbase, l1_size);
 265         l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
 266
 267         /* remap elog table */
 268         r = request_mem_region(elog_base, elog_size, "Elog Table");
 269         if (!r) {
 270                 pr_warn(FW_BUG EMCA_BUG,
 271                         (unsigned long long)elog_base,
 272                         (unsigned long long)elog_base + elog_size);
 273                 goto err_release_l1_dir;
 274         }
 275         elog_addr = acpi_os_map_iomem(elog_base, elog_size);
 276
 277         rc = -ENOMEM;
 278         /* allocate buffer to save elog record */
 279         elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL);
 280         if (elog_buf == NULL)
 281                 goto err_release_elog;
 282
 283         /*
 284          * eMCA event report method has higher priority than EDAC method,
 285          * unless EDAC event report method is mandatory.
 286          */
 287         old_edac_report_status = edac_get_report_status();
 288         edac_set_report_status(EDAC_REPORTING_DISABLED);
 289         mce_register_decode_chain(&extlog_mce_dec);
 290         /* enable OS to be involved to take over management from BIOS */
 291         ((struct extlog_l1_head *)extlog_l1_addr)->flags |= FLAG_OS_OPTIN;
 292
 293         return 0;
 294
 295 err_release_elog:
 296         if (elog_addr)
 297                 acpi_os_unmap_iomem(elog_addr, elog_size);
 298         release_mem_region(elog_base, elog_size);
 299 err_release_l1_dir:
 300         if (extlog_l1_addr)
 301                 acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
 302         release_mem_region(l1_dirbase, l1_size);
 303 err:
 304         pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
 305         return rc;
 306 }
 307
 308 static void __exit extlog_exit(void)
 309 {
 310         edac_set_report_status(old_edac_report_status);
 311         mce_unregister_decode_chain(&extlog_mce_dec);
 312         ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
 313         if (extlog_l1_addr)
 314                 acpi_os_unmap_iomem(extlog_l1_addr, l1_size);
 315         if (elog_addr)
 316                 acpi_os_unmap_iomem(elog_addr, elog_size);
 317         release_mem_region(elog_base, elog_size);
 318         release_mem_region(l1_dirbase, l1_size);
 319         kfree(elog_buf);
 320 }
 321
 322 module_init(extlog_init);
 323 module_exit(extlog_exit);
 324
 325 MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>");
 326 MODULE_DESCRIPTION("Extended MCA Error Log Driver");
 327 MODULE_LICENSE("GPL");