ACPI, APEI, HEST table parsing

obj-$(CONFIG_ACPI_APEI)		+= apei.o

apei-y := apei-base.o

apei-y := apei-base.o hest.o

/*

 * APEI Hardware Error Souce 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 <ying.huang@intel.com>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License version

 * 2 as published by the Free Software Foundation;

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */

#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 <acpi/apei.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 *hest_tab;

static int hest_void_parse(struct acpi_hest_header *hest_hdr, void *data)

{

	return 0;

}

static 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),

};

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);

	} 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);

	}

	BUG_ON(len == -1);

	return len;

};

int apei_hest_parse(apei_hest_func_t func, void *data)

{

	struct acpi_hest_header *hest_hdr;

	int i, rc, len;

	if (hest_disable)

		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_warning(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_warning(FW_BUG HEST_PFX

		"Table contents overflow for hardware error source: %d.\n",

				hest_hdr->source_id);

			return -EINVAL;

		}

		rc = func(hest_hdr, data);

		if (rc)

			return rc;

		hest_hdr = (void *)hest_hdr + len;

	}

	return 0;

}

EXPORT_SYMBOL_GPL(apei_hest_parse);

static int __init setup_hest_disable(char *str)

{

	hest_disable = 1;

	return 0;

}

__setup("hest_disable", setup_hest_disable);

static int __init hest_init(void)

{

	acpi_status status;

	int rc = -ENODEV;

	if (acpi_disabled)

		goto err;

	if (hest_disable) {

		pr_info(HEST_PFX "HEST tabling parsing is disabled.\n");

		goto err;

	}

	status = acpi_get_table(ACPI_SIG_HEST, 0,

				(struct acpi_table_header **)&hest_tab);

	if (status == AE_NOT_FOUND) {

		pr_info(HEST_PFX "Table is not found!\n");

		goto err;

	} else if (ACPI_FAILURE(status)) {

		const char *msg = acpi_format_exception(status);

		pr_err(HEST_PFX "Failed to get table, %s\n", msg);

		rc = -EINVAL;

		goto err;

	}

	rc = apei_hest_parse(hest_void_parse, NULL);

	if (rc)

		goto err;

	pr_info(HEST_PFX "HEST table parsing is initialized.\n");

	return 0;

err:

	hest_disable = 1;

	return rc;

}

subsys_initcall(hest_init);

/*

 * apei.h - ACPI Platform Error Interface

 */

#ifndef ACPI_APEI_H

#define ACPI_APEI_H

extern int hest_disable;

typedef int (*apei_hest_func_t)(struct acpi_hest_header *hest_hdr, void *data);

int apei_hest_parse(apei_hest_func_t func, void *data);

#endif