2 * Extended Error Log driver
4 * Copyright (C) 2013 Intel Corp.
5 * Author: Chen, Gong <gong.chen@intel.com>
7 * This file is licensed under GPLv2.
10 #include <linux/module.h>
11 #include <linux/acpi.h>
12 #include <linux/cper.h>
13 #include <linux/ratelimit.h>
17 #include "apei/apei-internal.h"
19 #define EXT_ELOG_ENTRY_MASK GENMASK_ULL(51, 0) /* elog entry address mask */
21 #define EXTLOG_DSM_REV 0x0
22 #define EXTLOG_FN_QUERY 0x0
23 #define EXTLOG_FN_ADDR 0x1
25 #define FLAG_OS_OPTIN BIT(0)
26 #define EXTLOG_QUERY_L1_EXIST BIT(1)
27 #define ELOG_ENTRY_VALID (1ULL<<63)
28 #define ELOG_ENTRY_LEN 0x1000
31 "Can not request iomem region <0x%016llx-0x%016llx> - eMCA disabled\n"
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 */
41 u32 entries; /* Valid L1 Directory entries per logical processor */
45 static u8 extlog_dsm_uuid[] = "663E35AF-CC10-41A4-88EA-5470AF055295";
47 /* L1 table related physical address */
49 static size_t elog_size;
50 static u64 l1_dirbase;
51 static size_t l1_size;
53 /* L1 table related virtual address */
54 static void __iomem *extlog_l1_addr;
55 static void __iomem *elog_addr;
57 static void *elog_buf;
59 static u64 *l1_entry_base;
60 static u32 l1_percpu_entry;
62 #define ELOG_IDX(cpu, bank) \
63 (cpu_physical_id(cpu) * l1_percpu_entry + (bank))
65 #define ELOG_ENTRY_DATA(idx) \
66 (*(l1_entry_base + (idx)))
68 #define ELOG_ENTRY_ADDR(phyaddr) \
69 (phyaddr - elog_base + (u8 *)elog_addr)
71 static struct acpi_generic_status *extlog_elog_entry_check(int cpu, int bank)
75 struct acpi_generic_status *estatus;
78 idx = ELOG_IDX(cpu, bank);
79 data = ELOG_ENTRY_DATA(idx);
80 if ((data & ELOG_ENTRY_VALID) == 0)
83 data &= EXT_ELOG_ENTRY_MASK;
84 estatus = (struct acpi_generic_status *)ELOG_ENTRY_ADDR(data);
86 /* if no valid data in elog entry, just return */
87 if (estatus->block_status == 0)
93 static void __print_extlog_rcd(const char *pfx,
94 struct acpi_generic_status *estatus, int cpu)
96 static atomic_t seqno;
97 unsigned int curr_seqno;
101 if (estatus->error_severity <= CPER_SEV_CORRECTED)
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);
112 static int print_extlog_rcd(const char *pfx,
113 struct acpi_generic_status *estatus, int cpu)
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;
120 if (estatus->error_severity == CPER_SEV_CORRECTED ||
121 (estatus->error_severity == CPER_SEV_INFORMATIONAL))
122 ratelimit = &ratelimit_corrected;
124 ratelimit = &ratelimit_uncorrected;
125 if (__ratelimit(ratelimit)) {
126 __print_extlog_rcd(pfx, estatus, cpu);
133 static int extlog_print(struct notifier_block *nb, unsigned long val,
136 struct mce *mce = (struct mce *)data;
137 int bank = mce->bank;
138 int cpu = mce->extcpu;
139 struct acpi_generic_status *estatus;
142 estatus = extlog_elog_entry_check(cpu, bank);
146 memcpy(elog_buf, (void *)estatus, ELOG_ENTRY_LEN);
147 /* clear record status to enable BIOS to update it again */
148 estatus->block_status = 0;
150 rc = print_extlog_rcd(NULL, (struct acpi_generic_status *)elog_buf, cpu);
155 static int extlog_get_dsm(acpi_handle handle, int rev, int func, u64 *ret)
157 struct acpi_buffer buf = {ACPI_ALLOCATE_BUFFER, NULL};
158 struct acpi_object_list input;
159 union acpi_object params[4], *obj;
163 acpi_str_to_uuid(extlog_dsm_uuid, uuid);
165 input.pointer = params;
166 params[0].type = ACPI_TYPE_BUFFER;
167 params[0].buffer.length = 16;
168 params[0].buffer.pointer = uuid;
169 params[1].type = ACPI_TYPE_INTEGER;
170 params[1].integer.value = rev;
171 params[2].type = ACPI_TYPE_INTEGER;
172 params[2].integer.value = func;
173 params[3].type = ACPI_TYPE_PACKAGE;
174 params[3].package.count = 0;
175 params[3].package.elements = NULL;
177 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_DSM", &input, &buf)))
181 obj = (union acpi_object *)buf.pointer;
182 if (obj->type == ACPI_TYPE_INTEGER) {
183 *ret = obj->integer.value;
184 } else if (obj->type == ACPI_TYPE_BUFFER) {
185 if (obj->buffer.length <= 8) {
186 for (i = 0; i < obj->buffer.length; i++)
187 *ret |= (obj->buffer.pointer[i] << (i * 8));
195 static bool extlog_get_l1addr(void)
200 if (ACPI_FAILURE(acpi_get_handle(NULL, "\\_SB", &handle)))
203 if (extlog_get_dsm(handle, EXTLOG_DSM_REV, EXTLOG_FN_QUERY, &ret) ||
204 !(ret & EXTLOG_QUERY_L1_EXIST))
207 if (extlog_get_dsm(handle, EXTLOG_DSM_REV, EXTLOG_FN_ADDR, &ret))
211 /* Spec says L1 directory must be 4K aligned, bail out if it isn't */
212 if (l1_dirbase & ((1 << 12) - 1)) {
213 pr_warn(FW_BUG "L1 Directory is invalid at physical %llx\n",
220 static struct notifier_block extlog_mce_dec = {
221 .notifier_call = extlog_print,
224 static int __init extlog_init(void)
226 struct extlog_l1_head *l1_head;
227 void __iomem *extlog_l1_hdr;
235 rdmsrl(MSR_IA32_MCG_CAP, cap);
236 if (!(cap & MCG_ELOG_P))
239 if (!extlog_get_l1addr())
243 /* get L1 header to fetch necessary information */
244 l1_hdr_size = sizeof(struct extlog_l1_head);
245 r = request_mem_region(l1_dirbase, l1_hdr_size, "L1 DIR HDR");
247 pr_warn(FW_BUG EMCA_BUG,
248 (unsigned long long)l1_dirbase,
249 (unsigned long long)l1_dirbase + l1_hdr_size);
253 extlog_l1_hdr = acpi_os_map_memory(l1_dirbase, l1_hdr_size);
254 l1_head = (struct extlog_l1_head *)extlog_l1_hdr;
255 l1_size = l1_head->total_len;
256 l1_percpu_entry = l1_head->entries;
257 elog_base = l1_head->elog_base;
258 elog_size = l1_head->elog_len;
259 acpi_os_unmap_memory(extlog_l1_hdr, l1_hdr_size);
260 release_mem_region(l1_dirbase, l1_hdr_size);
262 /* remap L1 header again based on completed information */
263 r = request_mem_region(l1_dirbase, l1_size, "L1 Table");
265 pr_warn(FW_BUG EMCA_BUG,
266 (unsigned long long)l1_dirbase,
267 (unsigned long long)l1_dirbase + l1_size);
270 extlog_l1_addr = acpi_os_map_memory(l1_dirbase, l1_size);
271 l1_entry_base = (u64 *)((u8 *)extlog_l1_addr + l1_hdr_size);
273 /* remap elog table */
274 r = request_mem_region(elog_base, elog_size, "Elog Table");
276 pr_warn(FW_BUG EMCA_BUG,
277 (unsigned long long)elog_base,
278 (unsigned long long)elog_base + elog_size);
279 goto err_release_l1_dir;
281 elog_addr = acpi_os_map_memory(elog_base, elog_size);
284 /* allocate buffer to save elog record */
285 elog_buf = kmalloc(ELOG_ENTRY_LEN, GFP_KERNEL);
286 if (elog_buf == NULL)
287 goto err_release_elog;
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;
297 acpi_os_unmap_memory(elog_addr, elog_size);
298 release_mem_region(elog_base, elog_size);
301 acpi_os_unmap_memory(extlog_l1_addr, l1_size);
302 release_mem_region(l1_dirbase, l1_size);
304 pr_warn(FW_BUG "Extended error log disabled because of problems parsing f/w tables\n");
308 static void __exit extlog_exit(void)
310 mce_unregister_decode_chain(&extlog_mce_dec);
311 ((struct extlog_l1_head *)extlog_l1_addr)->flags &= ~FLAG_OS_OPTIN;
313 acpi_os_unmap_memory(extlog_l1_addr, l1_size);
315 acpi_os_unmap_memory(elog_addr, elog_size);
316 release_mem_region(elog_base, elog_size);
317 release_mem_region(l1_dirbase, l1_size);
321 module_init(extlog_init);
322 module_exit(extlog_exit);
324 MODULE_AUTHOR("Chen, Gong <gong.chen@intel.com>");
325 MODULE_DESCRIPTION("Extended MCA Error Log Driver");
326 MODULE_LICENSE("GPL");