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"); 328