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/******************************************************************************

 *

 * Module Name: tbfadt   - FADT table utilities

 *

 *****************************************************************************/

/*

 * Copyright (C) 2000 - 2015, Intel Corp.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions, and the following disclaimer,

 *    without modification.

 * 2. Redistributions in binary form must reproduce at minimum a disclaimer

 *    substantially similar to the "NO WARRANTY" disclaimer below

 *    ("Disclaimer") and any redistribution must be conditioned upon

 *    including a substantially similar Disclaimer requirement for further

 *    binary redistribution.

 * 3. Neither the names of the above-listed copyright holders nor the names

 *    of any contributors may be used to endorse or promote products derived

 *    from this software without specific prior written permission.

 *

 * Alternatively, this software may be distributed under the terms of the

 * GNU General Public License ("GPL") version 2 as published by the Free

 * Software Foundation.

 *

 * NO WARRANTY

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,

 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING

 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

 * POSSIBILITY OF SUCH DAMAGES.

 */

#include 

#include "accommon.h"

#include "actables.h"

#define _COMPONENT          ACPI_TABLES

ACPI_MODULE_NAME("tbfadt")

/* Local prototypes */

static void

acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,

			     u8 space_id,

			     u8 byte_width,

			     u64 address, char *register_name, u8 flags);

static void acpi_tb_convert_fadt(void);

static void acpi_tb_setup_fadt_registers(void);

static u64

acpi_tb_select_address(char *register_name, u32 address32, u64 address64);

/* Table for conversion of FADT to common internal format and FADT validation */

typedef struct acpi_fadt_info {

	char *name;

	u16 address64;

	u16 address32;

	u16 length;

	u8 default_length;

	u8 flags;

} acpi_fadt_info;

#define ACPI_FADT_OPTIONAL          0

#define ACPI_FADT_REQUIRED          1

#define ACPI_FADT_SEPARATE_LENGTH   2

#define ACPI_FADT_GPE_REGISTER      4

static struct acpi_fadt_info fadt_info_table[] = {

	{"Pm1aEventBlock",

	 ACPI_FADT_OFFSET(xpm1a_event_block),

	 ACPI_FADT_OFFSET(pm1a_event_block),

	 ACPI_FADT_OFFSET(pm1_event_length),

	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */

	 ACPI_FADT_REQUIRED},

	{"Pm1bEventBlock",

	 ACPI_FADT_OFFSET(xpm1b_event_block),

	 ACPI_FADT_OFFSET(pm1b_event_block),

	 ACPI_FADT_OFFSET(pm1_event_length),

	 ACPI_PM1_REGISTER_WIDTH * 2,	/* Enable + Status register */

	 ACPI_FADT_OPTIONAL},

	{"Pm1aControlBlock",

	 ACPI_FADT_OFFSET(xpm1a_control_block),

	 ACPI_FADT_OFFSET(pm1a_control_block),

	 ACPI_FADT_OFFSET(pm1_control_length),

	 ACPI_PM1_REGISTER_WIDTH,

	 ACPI_FADT_REQUIRED},

	{"Pm1bControlBlock",

	 ACPI_FADT_OFFSET(xpm1b_control_block),

	 ACPI_FADT_OFFSET(pm1b_control_block),

	 ACPI_FADT_OFFSET(pm1_control_length),

	 ACPI_PM1_REGISTER_WIDTH,

	 ACPI_FADT_OPTIONAL},

	{"Pm2ControlBlock",

	 ACPI_FADT_OFFSET(xpm2_control_block),

	 ACPI_FADT_OFFSET(pm2_control_block),

	 ACPI_FADT_OFFSET(pm2_control_length),

	 ACPI_PM2_REGISTER_WIDTH,

	 ACPI_FADT_SEPARATE_LENGTH},

	{"PmTimerBlock",

	 ACPI_FADT_OFFSET(xpm_timer_block),

	 ACPI_FADT_OFFSET(pm_timer_block),

	 ACPI_FADT_OFFSET(pm_timer_length),

	 ACPI_PM_TIMER_WIDTH,

	 ACPI_FADT_SEPARATE_LENGTH},	/* ACPI 5.0A: Timer is optional */

	{"Gpe0Block",

	 ACPI_FADT_OFFSET(xgpe0_block),

	 ACPI_FADT_OFFSET(gpe0_block),

	 ACPI_FADT_OFFSET(gpe0_block_length),

	 0,

	 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER},

	{"Gpe1Block",

	 ACPI_FADT_OFFSET(xgpe1_block),

	 ACPI_FADT_OFFSET(gpe1_block),

	 ACPI_FADT_OFFSET(gpe1_block_length),

	 0,

	 ACPI_FADT_SEPARATE_LENGTH | ACPI_FADT_GPE_REGISTER}

};

#define ACPI_FADT_INFO_ENTRIES \

			(sizeof (fadt_info_table) / sizeof (struct acpi_fadt_info))

/* Table used to split Event Blocks into separate status/enable registers */

typedef struct acpi_fadt_pm_info {

	struct acpi_generic_address *target;

	u16 source;

	u8 register_num;

} acpi_fadt_pm_info;

static struct acpi_fadt_pm_info fadt_pm_info_table[] = {

	{&acpi_gbl_xpm1a_status,

	 ACPI_FADT_OFFSET(xpm1a_event_block),

	 0},

	{&acpi_gbl_xpm1a_enable,

	 ACPI_FADT_OFFSET(xpm1a_event_block),

	 1},

	{&acpi_gbl_xpm1b_status,

	 ACPI_FADT_OFFSET(xpm1b_event_block),

	 0},

	{&acpi_gbl_xpm1b_enable,

	 ACPI_FADT_OFFSET(xpm1b_event_block),

	 1}

};

#define ACPI_FADT_PM_INFO_ENTRIES \

			(sizeof (fadt_pm_info_table) / sizeof (struct acpi_fadt_pm_info))

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_init_generic_address

 *

 * PARAMETERS:  generic_address     - GAS struct to be initialized

 *              space_id            - ACPI Space ID for this register

 *              byte_width          - Width of this register

 *              address             - Address of the register

 *              register_name       - ASCII name of the ACPI register

 *

 * RETURN:      None

 *

 * DESCRIPTION: Initialize a Generic Address Structure (GAS)

 *              See the ACPI specification for a full description and

 *              definition of this structure.

 *

 ******************************************************************************/

static void

acpi_tb_init_generic_address(struct acpi_generic_address *generic_address,

			     u8 space_id,

			     u8 byte_width,

			     u64 address, char *register_name, u8 flags)

{

	u8 bit_width;

	/*

	 * Bit width field in the GAS is only one byte long, 255 max.

	 * Check for bit_width overflow in GAS.

	 */

	bit_width = (u8)(byte_width * 8);

	if (byte_width > 31) {	/* (31*8)=248, (32*8)=256 */

		/*

		 * No error for GPE blocks, because we do not use the bit_width

		 * for GPEs, the legacy length (byte_width) is used instead to

		 * allow for a large number of GPEs.

		 */

		if (!(flags & ACPI_FADT_GPE_REGISTER)) {

			ACPI_ERROR((AE_INFO,

				    "%s - 32-bit FADT register is too long (%u bytes, %u bits) "

				    "to convert to GAS struct - 255 bits max, truncating",

				    register_name, byte_width,

				    (byte_width * 8)));

		}

		bit_width = 255;

	}

	/*

	 * The 64-bit Address field is non-aligned in the byte packed

	 * GAS struct.

	 */

	ACPI_MOVE_64_TO_64(&generic_address->address, &address);

	/* All other fields are byte-wide */

	generic_address->space_id = space_id;

	generic_address->bit_width = bit_width;

	generic_address->bit_offset = 0;

	generic_address->access_width = 0;	/* Access width ANY */

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_select_address

 *

 * PARAMETERS:  register_name       - ASCII name of the ACPI register

 *              address32           - 32-bit address of the register

 *              address64           - 64-bit address of the register

 *

 * RETURN:      The resolved 64-bit address

 *

 * DESCRIPTION: Select between 32-bit and 64-bit versions of addresses within

 *              the FADT. Used for the FACS and DSDT addresses.

 *

 * NOTES:

 *

 * Check for FACS and DSDT address mismatches. An address mismatch between

 * the 32-bit and 64-bit address fields (FIRMWARE_CTRL/X_FIRMWARE_CTRL and

 * DSDT/X_DSDT) could be a corrupted address field or it might indicate

 * the presence of two FACS or two DSDT tables.

 *

 * November 2013:

 * By default, as per the ACPICA specification, a valid 64-bit address is

 * used regardless of the value of the 32-bit address. However, this

 * behavior can be overridden via the acpi_gbl_use32_bit_fadt_addresses flag.

 *

 ******************************************************************************/

static u64

acpi_tb_select_address(char *register_name, u32 address32, u64 address64)

{

	if (!address64) {

		/* 64-bit address is zero, use 32-bit address */

		return ((u64)address32);

	}

	if (address32 && (address64 != (u64)address32)) {

		/* Address mismatch between 32-bit and 64-bit versions */

		ACPI_BIOS_WARNING((AE_INFO,

				   "32/64X %s address mismatch in FADT: "

				   "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",

				   register_name, address32,

				   ACPI_FORMAT_UINT64(address64),

				   acpi_gbl_use32_bit_fadt_addresses ? 32 :

				   64));

		/* 32-bit address override */

		if (acpi_gbl_use32_bit_fadt_addresses) {

			return ((u64)address32);

		}

	}

	/* Default is to use the 64-bit address */

	return (address64);

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_parse_fadt

 *

 * PARAMETERS:  None

 *

 * RETURN:      None

 *

 * DESCRIPTION: Initialize the FADT, DSDT and FACS tables

 *              (FADT contains the addresses of the DSDT and FACS)

 *

 ******************************************************************************/

void acpi_tb_parse_fadt(void)

{

	u32 length;

	struct acpi_table_header *table;

	/*

	 * The FADT has multiple versions with different lengths,

	 * and it contains pointers to both the DSDT and FACS tables.

	 *

	 * Get a local copy of the FADT and convert it to a common format

	 * Map entire FADT, assumed to be smaller than one page.

	 */

	length = acpi_gbl_root_table_list.tables[acpi_gbl_fadt_index].length;

	table =

	    acpi_os_map_memory(acpi_gbl_root_table_list.

			       tables[acpi_gbl_fadt_index].address, length);

	if (!table) {

		return;

	}

	/*

	 * Validate the FADT checksum before we copy the table. Ignore

	 * checksum error as we want to try to get the DSDT and FACS.

	 */

	(void)acpi_tb_verify_checksum(table, length);

	/* Create a local copy of the FADT in common ACPI 2.0+ format */

	acpi_tb_create_local_fadt(table, length);

	/* All done with the real FADT, unmap it */

	acpi_os_unmap_memory(table, length);

	/* Obtain the DSDT and FACS tables via their addresses within the FADT */

	acpi_tb_install_fixed_table((acpi_physical_address) acpi_gbl_FADT.Xdsdt,

				    ACPI_SIG_DSDT, &acpi_gbl_dsdt_index);

	/* If Hardware Reduced flag is set, there is no FACS */

	if (!acpi_gbl_reduced_hardware) {

		if (acpi_gbl_FADT.facs) {

			acpi_tb_install_fixed_table((acpi_physical_address)

						    acpi_gbl_FADT.facs,

						    ACPI_SIG_FACS,

						    &acpi_gbl_facs_index);

		}

		if (acpi_gbl_FADT.Xfacs) {

			acpi_tb_install_fixed_table((acpi_physical_address)

						    acpi_gbl_FADT.Xfacs,

						    ACPI_SIG_FACS,

						    &acpi_gbl_xfacs_index);

		}

	}

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_create_local_fadt

 *

 * PARAMETERS:  table               - Pointer to BIOS FADT

 *              length              - Length of the table

 *

 * RETURN:      None

 *

 * DESCRIPTION: Get a local copy of the FADT and convert it to a common format.

 *              Performs validation on some important FADT fields.

 *

 * NOTE:        We create a local copy of the FADT regardless of the version.

 *

 ******************************************************************************/

void acpi_tb_create_local_fadt(struct acpi_table_header *table, u32 length)

{

	/*

	 * Check if the FADT is larger than the largest table that we expect

	 * (the ACPI 5.0 version). If so, truncate the table, and issue

	 * a warning.

	 */

	if (length > sizeof(struct acpi_table_fadt)) {

		ACPI_BIOS_WARNING((AE_INFO,

				   "FADT (revision %u) is longer than ACPI 5.0 version, "

				   "truncating length %u to %u",

				   table->revision, length,

				   (u32)sizeof(struct acpi_table_fadt)));

	}

	/* Clear the entire local FADT */

	memset(&acpi_gbl_FADT, 0, sizeof(struct acpi_table_fadt));

	/* Copy the original FADT, up to sizeof (struct acpi_table_fadt) */

	memcpy(&acpi_gbl_FADT, table,

	       ACPI_MIN(length, sizeof(struct acpi_table_fadt)));

	/* Take a copy of the Hardware Reduced flag */

	acpi_gbl_reduced_hardware = FALSE;

	if (acpi_gbl_FADT.flags & ACPI_FADT_HW_REDUCED) {

		acpi_gbl_reduced_hardware = TRUE;

	}

	/* Convert the local copy of the FADT to the common internal format */

	acpi_tb_convert_fadt();

	/* Initialize the global ACPI register structures */

	acpi_tb_setup_fadt_registers();

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_convert_fadt

 *

 * PARAMETERS:  none - acpi_gbl_FADT is used.

 *

 * RETURN:      None

 *

 * DESCRIPTION: Converts all versions of the FADT to a common internal format.

 *              Expand 32-bit addresses to 64-bit as necessary. Also validate

 *              important fields within the FADT.

 *

 * NOTE:        acpi_gbl_FADT must be of size (struct acpi_table_fadt), and must

 *              contain a copy of the actual BIOS-provided FADT.

 *

 * Notes on 64-bit register addresses:

 *

 * After this FADT conversion, later ACPICA code will only use the 64-bit "X"

 * fields of the FADT for all ACPI register addresses.

 *

 * The 64-bit X fields are optional extensions to the original 32-bit FADT

 * V1.0 fields. Even if they are present in the FADT, they are optional and

 * are unused if the BIOS sets them to zero. Therefore, we must copy/expand

 * 32-bit V1.0 fields to the 64-bit X fields if the the 64-bit X field is

 * originally zero.

 *

 * For ACPI 1.0 FADTs (that contain no 64-bit addresses), all 32-bit address

 * fields are expanded to the corresponding 64-bit X fields in the internal

 * common FADT.

 *

 * For ACPI 2.0+ FADTs, all valid (non-zero) 32-bit address fields are expanded

 * to the corresponding 64-bit X fields, if the 64-bit field is originally

 * zero. Adhering to the ACPI specification, we completely ignore the 32-bit

 * field if the 64-bit field is valid, regardless of whether the host OS is

 * 32-bit or 64-bit.

 *

 * Possible additional checks:

 *  (acpi_gbl_FADT.pm1_event_length >= 4)

 *  (acpi_gbl_FADT.pm1_control_length >= 2)

 *  (acpi_gbl_FADT.pm_timer_length >= 4)

 *  Gpe block lengths must be multiple of 2

 *

 ******************************************************************************/

static void acpi_tb_convert_fadt(void)

{

	char *name;

	struct acpi_generic_address *address64;

	u32 address32;

	u8 length;

	u8 flags;

	u32 i;

	/*

	 * For ACPI 1.0 FADTs (revision 1 or 2), ensure that reserved fields which

	 * should be zero are indeed zero. This will workaround BIOSs that

	 * inadvertently place values in these fields.

	 *

	 * The ACPI 1.0 reserved fields that will be zeroed are the bytes located

	 * at offset 45, 55, 95, and the word located at offset 109, 110.

	 *

	 * Note: The FADT revision value is unreliable. Only the length can be

	 * trusted.

	 */

	if (acpi_gbl_FADT.header.length <= ACPI_FADT_V2_SIZE) {

		acpi_gbl_FADT.preferred_profile = 0;

		acpi_gbl_FADT.pstate_control = 0;

		acpi_gbl_FADT.cst_control = 0;

		acpi_gbl_FADT.boot_flags = 0;

	}

	/*

	 * Now we can update the local FADT length to the length of the

	 * current FADT version as defined by the ACPI specification.

	 * Thus, we will have a common FADT internally.

	 */

	acpi_gbl_FADT.header.length = sizeof(struct acpi_table_fadt);

	/*

	 * Expand the 32-bit DSDT addresses to 64-bit as necessary.

	 * Later ACPICA code will always use the X 64-bit field.

	 */

	acpi_gbl_FADT.Xdsdt = acpi_tb_select_address("DSDT",

						     acpi_gbl_FADT.dsdt,

						     acpi_gbl_FADT.Xdsdt);

	/* If Hardware Reduced flag is set, we are all done */

	if (acpi_gbl_reduced_hardware) {

		return;

	}

	/* Examine all of the 64-bit extended address fields (X fields) */

	for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {

		/*

		 * Get the 32-bit and 64-bit addresses, as well as the register

		 * length and register name.

		 */

		address32 = *ACPI_ADD_PTR(u32,

					  &acpi_gbl_FADT,

					  fadt_info_table[i].address32);

		address64 = ACPI_ADD_PTR(struct acpi_generic_address,

					 &acpi_gbl_FADT,

					 fadt_info_table[i].address64);

		length = *ACPI_ADD_PTR(u8,

				       &acpi_gbl_FADT,

				       fadt_info_table[i].length);

		name = fadt_info_table[i].name;

		flags = fadt_info_table[i].flags;

		/*

		 * Expand the ACPI 1.0 32-bit addresses to the ACPI 2.0 64-bit "X"

		 * generic address structures as necessary. Later code will always use

		 * the 64-bit address structures.

		 *

		 * November 2013:

		 * Now always use the 64-bit address if it is valid (non-zero), in

		 * accordance with the ACPI specification which states that a 64-bit

		 * address supersedes the 32-bit version. This behavior can be

		 * overridden by the acpi_gbl_use32_bit_fadt_addresses flag.

		 *

		 * During 64-bit address construction and verification,

		 * these cases are handled:

		 *

		 * Address32 zero, Address64 [don't care]   - Use Address64

		 *

		 * Address32 non-zero, Address64 zero       - Copy/use Address32

		 * Address32 non-zero == Address64 non-zero - Use Address64

		 * Address32 non-zero != Address64 non-zero - Warning, use Address64

		 *

		 * Override: if acpi_gbl_use32_bit_fadt_addresses is TRUE, and:

		 * Address32 non-zero != Address64 non-zero - Warning, copy/use Address32

		 *

		 * Note: space_id is always I/O for 32-bit legacy address fields

		 */

		if (address32) {

			if (!address64->address) {

				/* 64-bit address is zero, use 32-bit address */

				acpi_tb_init_generic_address(address64,

							     ACPI_ADR_SPACE_SYSTEM_IO,

							     *ACPI_ADD_PTR(u8,

									   &acpi_gbl_FADT,

									   fadt_info_table

									   [i].

									   length),

							     (u64)address32,

							     name, flags);

			} else if (address64->address != (u64)address32) {

				/* Address mismatch */

				ACPI_BIOS_WARNING((AE_INFO,

						   "32/64X address mismatch in FADT/%s: "

						   "0x%8.8X/0x%8.8X%8.8X, using %u-bit address",

						   name, address32,

						   ACPI_FORMAT_UINT64

						   (address64->address),

						   acpi_gbl_use32_bit_fadt_addresses

						   ? 32 : 64));

				if (acpi_gbl_use32_bit_fadt_addresses) {

					/* 32-bit address override */

					acpi_tb_init_generic_address(address64,

								     ACPI_ADR_SPACE_SYSTEM_IO,

								     *ACPI_ADD_PTR

								     (u8,

								      &acpi_gbl_FADT,

								      fadt_info_table

								      [i].

								      length),

								     (u64)

								     address32,

								     name,

								     flags);

				}

			}

		}

		/*

		 * For each extended field, check for length mismatch between the

		 * legacy length field and the corresponding 64-bit X length field.

		 * Note: If the legacy length field is > 0xFF bits, ignore this

		 * check. (GPE registers can be larger than the 64-bit GAS structure

		 * can accomodate, 0xFF bits).

		 */

		if (address64->address &&

		    (ACPI_MUL_8(length) <= ACPI_UINT8_MAX) &&

		    (address64->bit_width != ACPI_MUL_8(length))) {

			ACPI_BIOS_WARNING((AE_INFO,

					   "32/64X length mismatch in FADT/%s: %u/%u",

					   name, ACPI_MUL_8(length),

					   address64->bit_width));

		}

		if (fadt_info_table[i].flags & ACPI_FADT_REQUIRED) {

			/*

			 * Field is required (Pm1a_event, Pm1a_control).

			 * Both the address and length must be non-zero.

			 */

			if (!address64->address || !length) {

				ACPI_BIOS_ERROR((AE_INFO,

						 "Required FADT field %s has zero address and/or length: "

						 "0x%8.8X%8.8X/0x%X",

						 name,

						 ACPI_FORMAT_UINT64(address64->

								    address),

						 length));

			}

		} else if (fadt_info_table[i].flags & ACPI_FADT_SEPARATE_LENGTH) {

			/*

			 * Field is optional (Pm2_control, GPE0, GPE1) AND has its own

			 * length field. If present, both the address and length must

			 * be valid.

			 */

			if ((address64->address && !length) ||

			    (!address64->address && length)) {

				ACPI_BIOS_WARNING((AE_INFO,

						   "Optional FADT field %s has zero address or length: "

						   "0x%8.8X%8.8X/0x%X",

						   name,

						   ACPI_FORMAT_UINT64

						   (address64->address),

						   length));

			}

		}

	}

}

/*******************************************************************************

 *

 * FUNCTION:    acpi_tb_setup_fadt_registers

 *

 * PARAMETERS:  None, uses acpi_gbl_FADT.

 *

 * RETURN:      None

 *

 * DESCRIPTION: Initialize global ACPI PM1 register definitions. Optionally,

 *              force FADT register definitions to their default lengths.

 *

 ******************************************************************************/

static void acpi_tb_setup_fadt_registers(void)

{

	struct acpi_generic_address *target64;

	struct acpi_generic_address *source64;

	u8 pm1_register_byte_width;

	u32 i;

	/*

	 * Optionally check all register lengths against the default values and

	 * update them if they are incorrect.

	 */

	if (acpi_gbl_use_default_register_widths) {

		for (i = 0; i < ACPI_FADT_INFO_ENTRIES; i++) {

			target64 =

			    ACPI_ADD_PTR(struct acpi_generic_address,

					 &acpi_gbl_FADT,

					 fadt_info_table[i].address64);

			/*

			 * If a valid register (Address != 0) and the (default_length > 0)

			 * (Not a GPE register), then check the width against the default.

			 */

			if ((target64->address) &&

			    (fadt_info_table[i].default_length > 0) &&

			    (fadt_info_table[i].default_length !=

			     target64->bit_width)) {

				ACPI_BIOS_WARNING((AE_INFO,

						   "Invalid length for FADT/%s: %u, using default %u",

						   fadt_info_table[i].name,

						   target64->bit_width,

						   fadt_info_table[i].

						   default_length));

				/* Incorrect size, set width to the default */

				target64->bit_width =

				    fadt_info_table[i].default_length;

			}

		}

	}

	/*

	 * Get the length of the individual PM1 registers (enable and status).

	 * Each register is defined to be (event block length / 2). Extra divide

	 * by 8 converts bits to bytes.

	 */

	pm1_register_byte_width = (u8)

	    ACPI_DIV_16(acpi_gbl_FADT.xpm1a_event_block.bit_width);

	/*

	 * Calculate separate GAS structs for the PM1x (A/B) Status and Enable

	 * registers. These addresses do not appear (directly) in the FADT, so it

	 * is useful to pre-calculate them from the PM1 Event Block definitions.

	 *

	 * The PM event blocks are split into two register blocks, first is the

	 * PM Status Register block, followed immediately by the PM Enable

	 * Register block. Each is of length (pm1_event_length/2)

	 *

	 * Note: The PM1A event block is required by the ACPI specification.

	 * However, the PM1B event block is optional and is rarely, if ever,

	 * used.

	 */

	for (i = 0; i < ACPI_FADT_PM_INFO_ENTRIES; i++) {

		source64 =

		    ACPI_ADD_PTR(struct acpi_generic_address, &acpi_gbl_FADT,

				 fadt_pm_info_table[i].source);

		if (source64->address) {

			acpi_tb_init_generic_address(fadt_pm_info_table[i].

						     target, source64->space_id,

						     pm1_register_byte_width,

						     source64->address +

						     (fadt_pm_info_table[i].

						      register_num *

						      pm1_register_byte_width),

						     "PmRegisters", 0);

		}

	}

}