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 rdmsrl(MSR_IA32_MCG_CAP, cap); 226 227 if (!(cap & MCG_ELOG_P) || !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"); 315