diff options
Diffstat (limited to 'drivers/acpi/apei/bert.c')
| -rw-r--r-- | drivers/acpi/apei/bert.c | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/drivers/acpi/apei/bert.c b/drivers/acpi/apei/bert.c new file mode 100644 index 000000000..45973aa6e --- /dev/null +++ b/drivers/acpi/apei/bert.c @@ -0,0 +1,170 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * APEI Boot Error Record Table (BERT) support + * + * Copyright 2011 Intel Corp. + * Author: Huang Ying <ying.huang@intel.com> + * + * Under normal circumstances, when a hardware error occurs, the error + * handler receives control and processes the error. This gives OSPM a + * chance to process the error condition, report it, and optionally attempt + * recovery. In some cases, the system is unable to process an error. + * For example, system firmware or a management controller may choose to + * reset the system or the system might experience an uncontrolled crash + * or reset.The boot error source is used to report unhandled errors that + * occurred in a previous boot. This mechanism is described in the BERT + * table. + * + * For more information about BERT, please refer to ACPI Specification + * version 4.0, section 17.3.1 + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/acpi.h> +#include <linux/io.h> + +#include "apei-internal.h" + +#undef pr_fmt +#define pr_fmt(fmt) "BERT: " fmt + +#define ACPI_BERT_PRINT_MAX_RECORDS 5 +#define ACPI_BERT_PRINT_MAX_LEN 1024 + +static int bert_disable; + +/* + * Print "all" the error records in the BERT table, but avoid huge spam to + * the console if the BIOS included oversize records, or too many records. + * Skipping some records here does not lose anything because the full + * data is available to user tools in: + * /sys/firmware/acpi/tables/data/BERT + */ +static void __init bert_print_all(struct acpi_bert_region *region, + unsigned int region_len) +{ + struct acpi_hest_generic_status *estatus = + (struct acpi_hest_generic_status *)region; + int remain = region_len; + int printed = 0, skipped = 0; + u32 estatus_len; + + while (remain >= sizeof(struct acpi_bert_region)) { + estatus_len = cper_estatus_len(estatus); + if (remain < estatus_len) { + pr_err(FW_BUG "Truncated status block (length: %u).\n", + estatus_len); + break; + } + + /* No more error records. */ + if (!estatus->block_status) + break; + + if (cper_estatus_check(estatus)) { + pr_err(FW_BUG "Invalid error record.\n"); + break; + } + + if (estatus_len < ACPI_BERT_PRINT_MAX_LEN && + printed < ACPI_BERT_PRINT_MAX_RECORDS) { + pr_info_once("Error records from previous boot:\n"); + cper_estatus_print(KERN_INFO HW_ERR, estatus); + printed++; + } else { + skipped++; + } + + /* + * Because the boot error source is "one-time polled" type, + * clear Block Status of current Generic Error Status Block, + * once it's printed. + */ + estatus->block_status = 0; + + estatus = (void *)estatus + estatus_len; + remain -= estatus_len; + } + + if (skipped) + pr_info(HW_ERR "Skipped %d error records\n", skipped); +} + +static int __init setup_bert_disable(char *str) +{ + bert_disable = 1; + + return 1; +} +__setup("bert_disable", setup_bert_disable); + +static int __init bert_check_table(struct acpi_table_bert *bert_tab) +{ + if (bert_tab->header.length < sizeof(struct acpi_table_bert) || + bert_tab->region_length < sizeof(struct acpi_bert_region)) + return -EINVAL; + + return 0; +} + +static int __init bert_init(void) +{ + struct apei_resources bert_resources; + struct acpi_bert_region *boot_error_region; + struct acpi_table_bert *bert_tab; + unsigned int region_len; + acpi_status status; + int rc = 0; + + if (acpi_disabled) + return 0; + + if (bert_disable) { + pr_info("Boot Error Record Table support is disabled.\n"); + return 0; + } + + status = acpi_get_table(ACPI_SIG_BERT, 0, (struct acpi_table_header **)&bert_tab); + if (status == AE_NOT_FOUND) + return 0; + + if (ACPI_FAILURE(status)) { + pr_err("get table failed, %s.\n", acpi_format_exception(status)); + return -EINVAL; + } + + rc = bert_check_table(bert_tab); + if (rc) { + pr_err(FW_BUG "table invalid.\n"); + goto out_put_bert_tab; + } + + region_len = bert_tab->region_length; + apei_resources_init(&bert_resources); + rc = apei_resources_add(&bert_resources, bert_tab->address, + region_len, true); + if (rc) + goto out_put_bert_tab; + rc = apei_resources_request(&bert_resources, "APEI BERT"); + if (rc) + goto out_fini; + boot_error_region = ioremap_cache(bert_tab->address, region_len); + if (boot_error_region) { + bert_print_all(boot_error_region, region_len); + iounmap(boot_error_region); + } else { + rc = -ENOMEM; + } + + apei_resources_release(&bert_resources); +out_fini: + apei_resources_fini(&bert_resources); +out_put_bert_tab: + acpi_put_table((struct acpi_table_header *)bert_tab); + + return rc; +} + +late_initcall(bert_init); |