// SPDX-License-Identifier: GPL-2.0-only
/*
* APEI Hardware Error Source Table support
*
* HEST describes error sources in detail; communicates operational
* parameters (i.e. severity levels, masking bits, and threshold
* values) to Linux as necessary. It also allows the BIOS to report
* non-standard error sources to Linux (for example, chipset-specific
* error registers).
*
* For more information about HEST, please refer to ACPI Specification
* version 4.0, section 17.3.2.
*
* Copyright 2009 Intel Corp.
* Author: Huang Ying <[email protected]>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/acpi.h>
#include <linux/kdebug.h>
#include <linux/highmem.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <acpi/apei.h>
#include <acpi/ghes.h>
#include "apei-internal.h"
#define HEST_PFX "HEST: "
int hest_disable;
EXPORT_SYMBOL_GPL(hest_disable);
/* HEST table parsing */
static struct acpi_table_hest *__read_mostly hest_tab;
/*
* Since GHES_ASSIST is not supported, skip initialization of GHES_ASSIST
* structures for MCA.
* During HEST parsing, detected MCA error sources are cached from early
* table entries so that the Flags and Source Id fields from these cached
* values are then referred to in later table entries to determine if the
* encountered GHES_ASSIST structure should be initialized.
*/
static struct {
struct acpi_hest_ia_corrected *cmc;
struct acpi_hest_ia_machine_check *mc;
struct acpi_hest_ia_deferred_check *dmc;
} mces;
static const int hest_esrc_len_tab[ACPI_HEST_TYPE_RESERVED] = {
[ACPI_HEST_TYPE_IA32_CHECK] = -1, /* need further calculation */
[ACPI_HEST_TYPE_IA32_CORRECTED_CHECK] = -1,
[ACPI_HEST_TYPE_IA32_NMI] = sizeof(struct acpi_hest_ia_nmi),
[ACPI_HEST_TYPE_AER_ROOT_PORT] = sizeof(struct acpi_hest_aer_root),
[ACPI_HEST_TYPE_AER_ENDPOINT] = sizeof(struct acpi_hest_aer),
[ACPI_HEST_TYPE_AER_BRIDGE] = sizeof(struct acpi_hest_aer_bridge),
[ACPI_HEST_TYPE_GENERIC_ERROR] = sizeof(struct acpi_hest_generic),
[ACPI_HEST_TYPE_GENERIC_ERROR_V2] = sizeof(struct acpi_hest_generic_v2),
[ACPI_HEST_TYPE_IA32_DEFERRED_CHECK] = -1,
};
static inline bool is_generic_error(struct acpi_hest_header *hest_hdr)
{
return hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR ||
hest_hdr->type == ACPI_HEST_TYPE_GENERIC_ERROR_V2;
}
static int hest_esrc_len(struct acpi_hest_header *hest_hdr)
{
u16 hest_type = hest_hdr->type;
int len;
if (hest_type >= ACPI_HEST_TYPE_RESERVED)
return 0;
len = hest_esrc_len_tab[hest_type];
if (hest_type == ACPI_HEST_TYPE_IA32_CORRECTED_CHECK) {
struct acpi_hest_ia_corrected *cmc;
cmc = (struct acpi_hest_ia_corrected *)hest_hdr;
len = sizeof(*cmc) + cmc->num_hardware_banks *
sizeof(struct acpi_hest_ia_error_bank);
mces.cmc = cmc;
} else if (hest_type == ACPI_HEST_TYPE_IA32_CHECK) {
struct acpi_hest_ia_machine_check *mc;
mc = (struct acpi_hest_ia_machine_check *)hest_hdr;
len = sizeof(*mc) + mc->num_hardware_banks *
sizeof(struct acpi_hest_ia_error_bank);
mces.mc = mc;
} else if (hest_type == ACPI_HEST_TYPE_IA32_DEFERRED_CHECK) {
struct acpi_hest_ia_deferred_check *mc;
mc = (struct acpi_hest_ia_deferred_check *)hest_hdr;
len = sizeof(*mc) + mc->num_hardware_banks *
sizeof(struct acpi_hest_ia_error_bank);
mces.dmc = mc;
}
BUG_ON(len == -1);
return len;
};
/*
* GHES and GHESv2 structures share the same format, starting from
* Source Id and ending in Error Status Block Length (inclusive).
*/
static bool is_ghes_assist_struct(struct acpi_hest_header *hest_hdr)
{
struct acpi_hest_generic *ghes;
u16 related_source_id;
if (hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR &&
hest_hdr->type != ACPI_HEST_TYPE_GENERIC_ERROR_V2)
return false;
ghes = (struct acpi_hest_generic *)hest_hdr;
related_source_id = ghes->related_source_id;
if (mces.cmc && mces.cmc->flags & ACPI_HEST_GHES_ASSIST &&
related_source_id == mces.cmc->header.source_id)
return true;
if (mces.mc && mces.mc->flags & ACPI_HEST_GHES_ASSIST &&
related_source_id == mces.mc->header.source_id)
return true;
if (mces.dmc && mces.dmc->flags & ACPI_HEST_GHES_ASSIST &&
related_source_id == mces.dmc->header.source_id)
return true;
return false;
}
typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data);
static int apei_hest_parse(apei_hest_func_t func, void *data)
{
struct acpi_hest_header *hest_hdr;
int i, rc, len;
if (hest_disable || !hest_tab)
return -EINVAL;
hest_hdr = (struct acpi_hest_header *)(hest_tab + 1);
for (i = 0; i < hest_tab->error_source_count; i++) {
len = hest_esrc_len(hest_hdr);
if (!len) {
pr_warn(FW_WARN HEST_PFX
"Unknown or unused hardware error source "
"type: %d for hardware error source: %d.\n",
hest_hdr->type, hest_hdr->source_id);
return -EINVAL;
}
if ((void *)hest_hdr + len >
(void *)hest_tab + hest_tab->header.length) {
pr_warn(FW_BUG HEST_PFX
"Table contents overflow for hardware error source: %d.\n",
hest_hdr->source_id);
return -EINVAL;
}
if (is_ghes_assist_struct(hest_hdr)) {
hest_hdr = (void *)hest_hdr + len;
continue;
}
rc = func(hest_hdr, data);
if (rc)
return rc;
hest_hdr = (void *)hest_hdr + len;
}
return 0;
}
/*
* Check if firmware advertises firmware first mode. We need FF bit to be set
* along with a set of MC banks which work in FF mode.
*/
static int __init hest_parse_cmc(struct acpi_hest_header *hest_hdr, void *data)
{
if (hest_hdr->type != ACPI_HEST_TYPE_IA32_CORRECTED_CHECK)
return 0;
if (!acpi_disable_cmcff)
return !arch_apei_enable_cmcff(hest_hdr, data);
return 0;
}
struct ghes_arr {
struct platform_device **ghes_devs;
unsigned int count;
};
static int __init hest_parse_ghes_count(struct acpi_hest_header *hest_hdr, void *data)
{
int *count = data;
if (is_generic_error(hest_hdr))
(*count)++;
return 0;
}
static int __init hest_parse_ghes(struct acpi_hest_header *hest_hdr, void *data)
{
struct platform_device *ghes_dev;
struct ghes_arr *ghes_arr = data;
int rc, i;
if (!is_generic_error(hest_hdr))
return 0;
if (!((struct acpi_hest_generic *)hest_hdr)->enabled)
return 0;
for (i = 0; i < ghes_arr->count; i++) {
struct acpi_hest_header *hdr;
ghes_dev = ghes_arr->ghes_devs[i];
hdr = *(struct acpi_hest_header **)ghes_dev->dev.platform_data;
if (hdr->source_id == hest_hdr->source_id) {
pr_warn(FW_WARN HEST_PFX "Duplicated hardware error source ID: %d.\n",
hdr->source_id);
return -EIO;
}
}
ghes_dev = platform_device_alloc("GHES", hest_hdr->source_id);
if (!ghes_dev)
return -ENOMEM;
rc = platform_device_add_data(ghes_dev, &hest_hdr, sizeof(void *));
if (rc)
goto err;
rc = platform_device_add(ghes_dev);
if (rc)
goto err;
ghes_arr->ghes_devs[ghes_arr->count++] = ghes_dev;
return 0;
err:
platform_device_put(ghes_dev);
return rc;
}
static int __init hest_ghes_dev_register(unsigned int ghes_count)
{
int rc, i;
struct ghes_arr ghes_arr;
ghes_arr.count = 0;
ghes_arr.ghes_devs = kmalloc_array(ghes_count, sizeof(void *),
GFP_KERNEL);
if (!ghes_arr.ghes_devs)
return -ENOMEM;
rc = apei_hest_parse(hest_parse_ghes, &ghes_arr);
if (rc)
goto err;
rc = ghes_estatus_pool_init(ghes_count);
if (rc)
goto err;
out:
kfree(ghes_arr.ghes_devs);
return rc;
err:
for (i = 0; i < ghes_arr.count; i++)
platform_device_unregister(ghes_arr.ghes_devs[i]);
goto out;
}
static int __init setup_hest_disable(char *str)
{
hest_disable = HEST_DISABLED;
return 1;
}
__setup("hest_disable", setup_hest_disable);
void __init acpi_hest_init(void)
{
acpi_status status;
int rc;
unsigned int ghes_count = 0;
if (hest_disable) {
pr_info(HEST_PFX "Table parsing disabled.\n");
return;
}
status = acpi_get_table(ACPI_SIG_HEST, 0,
(struct acpi_table_header **)&hest_tab);
if (status == AE_NOT_FOUND) {
hest_disable = HEST_NOT_FOUND;
return;
} else if (ACPI_FAILURE(status)) {
const char *msg = acpi_format_exception(status);
pr_err(HEST_PFX "Failed to get table, %s\n", msg);
hest_disable = HEST_DISABLED;
return;
}
rc = apei_hest_parse(hest_parse_cmc, NULL);
if (rc)
goto err;
if (!ghes_disable) {
rc = apei_hest_parse(hest_parse_ghes_count, &ghes_count);
if (rc)
goto err;
if (ghes_count)
rc = hest_ghes_dev_register(ghes_count);
if (rc)
goto err;
}
pr_info(HEST_PFX "Table parsing has been initialized.\n");
return;
err:
hest_disable = HEST_DISABLED;
acpi_put_table((struct acpi_table_header *)hest_tab);
}
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