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 uuid_le *fru_id = &NULL_UUID_LE; 145 char *fru_text = ""; 146 uuid_le *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 = (uuid_le *)gdata->fru_id; 169 if (gdata->validation_bits & CPER_SEC_VALID_FRU_TEXT) 170 fru_text = gdata->fru_text; 171 sec_type = (uuid_le *)gdata->section_type; 172 if (!uuid_le_cmp(*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 u8 uuid[16]; 186 acpi_handle handle; 187 union acpi_object *obj; 188 189 acpi_str_to_uuid(extlog_dsm_uuid, uuid); 190 191 if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle))) 192 return false; 193 if (!acpi_check_dsm(handle, uuid, EXTLOG_DSM_REV, 1 << EXTLOG_FN_ADDR)) 194 return false; 195 obj = acpi_evaluate_dsm_typed(handle, uuid, 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 }; 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 (get_edac_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 = get_edac_report_status(); 288 set_edac_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 set_edac_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"); 328