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