utmisc.c

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/*******************************************************************************
 *
 * Module Name: utmisc - common utility procedures
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2007, R. Byron Moore
 * 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 <linux/module.h>

#include <acpi/acpi.h>
#include <acpi/acnamesp.h>

#define _COMPONENT          ACPI_UTILITIES
ACPI_MODULE_NAME("utmisc")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_validate_exception
 *
 * PARAMETERS:  Status       - The acpi_status code to be formatted
 *
 * RETURN:      A string containing the exception text. NULL if exception is
 *              not valid.
 *
 * DESCRIPTION: This function validates and translates an ACPI exception into
 *              an ASCII string.
 *
 ******************************************************************************/
const char *acpi_ut_validate_exception(acpi_status status)
{
	acpi_status sub_status;
	const char *exception = NULL;

	ACPI_FUNCTION_ENTRY();

	/*
	 * Status is composed of two parts, a "type" and an actual code
	 */
	sub_status = (status & ~AE_CODE_MASK);

	switch (status & AE_CODE_MASK) {
	case AE_CODE_ENVIRONMENTAL:

		if (sub_status <= AE_CODE_ENV_MAX) {
			exception = acpi_gbl_exception_names_env[sub_status];
		}
		break;

	case AE_CODE_PROGRAMMER:

		if (sub_status <= AE_CODE_PGM_MAX) {
			exception =
			    acpi_gbl_exception_names_pgm[sub_status - 1];
		}
		break;

	case AE_CODE_ACPI_TABLES:

		if (sub_status <= AE_CODE_TBL_MAX) {
			exception =
			    acpi_gbl_exception_names_tbl[sub_status - 1];
		}
		break;

	case AE_CODE_AML:

		if (sub_status <= AE_CODE_AML_MAX) {
			exception =
			    acpi_gbl_exception_names_aml[sub_status - 1];
		}
		break;

	case AE_CODE_CONTROL:

		if (sub_status <= AE_CODE_CTRL_MAX) {
			exception =
			    acpi_gbl_exception_names_ctrl[sub_status - 1];
		}
		break;

	default:
		break;
	}

	return (ACPI_CAST_PTR(const char, exception));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_is_aml_table
 *
 * PARAMETERS:  Table               - An ACPI table
 *
 * RETURN:      TRUE if table contains executable AML; FALSE otherwise
 *
 * DESCRIPTION: Check ACPI Signature for a table that contains AML code.
 *              Currently, these are DSDT,SSDT,PSDT. All other table types are
 *              data tables that do not contain AML code.
 *
 ******************************************************************************/

u8 acpi_ut_is_aml_table(struct acpi_table_header *table)
{

	/* These are the only tables that contain executable AML */

	if (ACPI_COMPARE_NAME(table->signature, ACPI_SIG_DSDT) ||
	    ACPI_COMPARE_NAME(table->signature, ACPI_SIG_PSDT) ||
	    ACPI_COMPARE_NAME(table->signature, ACPI_SIG_SSDT)) {
		return (TRUE);
	}

	return (FALSE);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_allocate_owner_id
 *
 * PARAMETERS:  owner_id        - Where the new owner ID is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
 *              track objects created by the table or method, to be deleted
 *              when the method exits or the table is unloaded.
 *
 ******************************************************************************/

acpi_status acpi_ut_allocate_owner_id(acpi_owner_id * owner_id)
{
	acpi_native_uint i;
	acpi_native_uint j;
	acpi_native_uint k;
	acpi_status status;

	ACPI_FUNCTION_TRACE(ut_allocate_owner_id);

	/* Guard against multiple allocations of ID to the same location */

	if (*owner_id) {
		ACPI_ERROR((AE_INFO, "Owner ID [%2.2X] already exists",
			    *owner_id));
		return_ACPI_STATUS(AE_ALREADY_EXISTS);
	}

	/* Mutex for the global ID mask */

	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * Find a free owner ID, cycle through all possible IDs on repeated
	 * allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index may have
	 * to be scanned twice.
	 */
	for (i = 0, j = acpi_gbl_last_owner_id_index;
	     i < (ACPI_NUM_OWNERID_MASKS + 1); i++, j++) {
		if (j >= ACPI_NUM_OWNERID_MASKS) {
			j = 0;	/* Wraparound to start of mask array */
		}

		for (k = acpi_gbl_next_owner_id_offset; k < 32; k++) {
			if (acpi_gbl_owner_id_mask[j] == ACPI_UINT32_MAX) {

				/* There are no free IDs in this mask */

				break;
			}

			if (!(acpi_gbl_owner_id_mask[j] & (1 << k))) {
				/*
				 * Found a free ID. The actual ID is the bit index plus one,
				 * making zero an invalid Owner ID. Save this as the last ID
				 * allocated and update the global ID mask.
				 */
				acpi_gbl_owner_id_mask[j] |= (1 << k);

				acpi_gbl_last_owner_id_index = (u8) j;
				acpi_gbl_next_owner_id_offset = (u8) (k + 1);

				/*
				 * Construct encoded ID from the index and bit position
				 *
				 * Note: Last [j].k (bit 255) is never used and is marked
				 * permanently allocated (prevents +1 overflow)
				 */
				*owner_id =
				    (acpi_owner_id) ((k + 1) + ACPI_MUL_32(j));

				ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
						  "Allocated OwnerId: %2.2X\n",
						  (unsigned int)*owner_id));
				goto exit;
			}
		}

		acpi_gbl_next_owner_id_offset = 0;
	}

	/*
	 * All owner_ids have been allocated. This typically should
	 * not happen since the IDs are reused after deallocation. The IDs are
	 * allocated upon table load (one per table) and method execution, and
	 * they are released when a table is unloaded or a method completes
	 * execution.
	 *
	 * If this error happens, there may be very deep nesting of invoked control
	 * methods, or there may be a bug where the IDs are not released.
	 */
	status = AE_OWNER_ID_LIMIT;
	ACPI_ERROR((AE_INFO,
		    "Could not allocate new OwnerId (255 max), AE_OWNER_ID_LIMIT"));

      exit:
	(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
	return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_release_owner_id
 *
 * PARAMETERS:  owner_id_ptr        - Pointer to a previously allocated owner_iD
 *
 * RETURN:      None. No error is returned because we are either exiting a
 *              control method or unloading a table. Either way, we would
 *              ignore any error anyway.
 *
 * DESCRIPTION: Release a table or method owner ID.  Valid IDs are 1 - 255
 *
 ******************************************************************************/

void acpi_ut_release_owner_id(acpi_owner_id * owner_id_ptr)
{
	acpi_owner_id owner_id = *owner_id_ptr;
	acpi_status status;
	acpi_native_uint index;
	u32 bit;

	ACPI_FUNCTION_TRACE_U32(ut_release_owner_id, owner_id);

	/* Always clear the input owner_id (zero is an invalid ID) */

	*owner_id_ptr = 0;

	/* Zero is not a valid owner_iD */

	if (owner_id == 0) {
		ACPI_ERROR((AE_INFO, "Invalid OwnerId: %2.2X", owner_id));
		return_VOID;
	}

	/* Mutex for the global ID mask */

	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
	if (ACPI_FAILURE(status)) {
		return_VOID;
	}

	/* Normalize the ID to zero */

	owner_id--;

	/* Decode ID to index/offset pair */

	index = ACPI_DIV_32(owner_id);
	bit = 1 << ACPI_MOD_32(owner_id);

	/* Free the owner ID only if it is valid */

	if (acpi_gbl_owner_id_mask[index] & bit) {
		acpi_gbl_owner_id_mask[index] ^= bit;
	} else {
		ACPI_ERROR((AE_INFO,
			    "Release of non-allocated OwnerId: %2.2X",
			    owner_id + 1));
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
	return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_strupr (strupr)
 *
 * PARAMETERS:  src_string      - The source string to convert
 *
 * RETURN:      None
 *
 * DESCRIPTION: Convert string to uppercase
 *
 * NOTE: This is not a POSIX function, so it appears here, not in utclib.c
 *
 ******************************************************************************/

void acpi_ut_strupr(char *src_string)
{
	char *string;

	ACPI_FUNCTION_ENTRY();

	if (!src_string) {
		return;
	}

	/* Walk entire string, uppercasing the letters */

	for (string = src_string; *string; string++) {
		*string = (char)ACPI_TOUPPER(*string);
	}

	return;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_print_string
 *
 * PARAMETERS:  String          - Null terminated ASCII string
 *              max_length      - Maximum output length
 *
 * RETURN:      None
 *
 * DESCRIPTION: Dump an ASCII string with support for ACPI-defined escape
 *              sequences.
 *
 ******************************************************************************/

void acpi_ut_print_string(char *string, u8 max_length)
{
	u32 i;

	if (!string) {
		acpi_os_printf("<\"NULL STRING PTR\">");
		return;
	}

	acpi_os_printf("\"");
	for (i = 0; string[i] && (i < max_length); i++) {

		/* Escape sequences */

		switch (string[i]) {
		case 0x07:
			acpi_os_printf("\\a");	/* BELL */
			break;

		case 0x08:
			acpi_os_printf("\\b");	/* BACKSPACE */
			break;

		case 0x0C:
			acpi_os_printf("\\f");	/* FORMFEED */
			break;

		case 0x0A:
			acpi_os_printf("\\n");	/* LINEFEED */
			break;

		case 0x0D:
			acpi_os_printf("\\r");	/* CARRIAGE RETURN */
			break;

		case 0x09:
			acpi_os_printf("\\t");	/* HORIZONTAL TAB */
			break;

		case 0x0B:
			acpi_os_printf("\\v");	/* VERTICAL TAB */
			break;

		case '\'':	/* Single Quote */
		case '\"':	/* Double Quote */
		case '\\':	/* Backslash */
			acpi_os_printf("\\%c", (int)string[i]);
			break;

		default:

			/* Check for printable character or hex escape */

			if (ACPI_IS_PRINT(string[i])) {
				/* This is a normal character */

				acpi_os_printf("%c", (int)string[i]);
			} else {
				/* All others will be Hex escapes */

				acpi_os_printf("\\x%2.2X", (s32) string[i]);
			}
			break;
		}
	}
	acpi_os_printf("\"");

	if (i == max_length && string[i]) {
		acpi_os_printf("...");
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_dword_byte_swap
 *
 * PARAMETERS:  Value           - Value to be converted
 *
 * RETURN:      u32 integer with bytes swapped
 *
 * DESCRIPTION: Convert a 32-bit value to big-endian (swap the bytes)
 *
 ******************************************************************************/

u32 acpi_ut_dword_byte_swap(u32 value)
{
	union {
		u32 value;
		u8 bytes[4];
	} out;
	union {
		u32 value;
		u8 bytes[4];
	} in;

	ACPI_FUNCTION_ENTRY();

	in.value = value;

	out.bytes[0] = in.bytes[3];
	out.bytes[1] = in.bytes[2];
	out.bytes[2] = in.bytes[1];
	out.bytes[3] = in.bytes[0];

	return (out.value);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_set_integer_width
 *
 * PARAMETERS:  Revision            From DSDT header
 *
 * RETURN:      None
 *
 * DESCRIPTION: Set the global integer bit width based upon the revision
 *              of the DSDT.  For Revision 1 and 0, Integers are 32 bits.
 *              For Revision 2 and above, Integers are 64 bits.  Yes, this
 *              makes a difference.
 *
 ******************************************************************************/

void acpi_ut_set_integer_width(u8 revision)
{

	if (revision < 2) {

		/* 32-bit case */

		acpi_gbl_integer_bit_width = 32;
		acpi_gbl_integer_nybble_width = 8;
		acpi_gbl_integer_byte_width = 4;
	} else {
		/* 64-bit case (ACPI 2.0+) */

		acpi_gbl_integer_bit_width = 64;
		acpi_gbl_integer_nybble_width = 16;
		acpi_gbl_integer_byte_width = 8;
	}
}

#ifdef ACPI_DEBUG_OUTPUT
/*******************************************************************************
 *
 * FUNCTION:    acpi_ut_display_init_pathname
 *
 * PARAMETERS:  Type                - Object type of the node
 *              obj_handle          - Handle whose pathname will be displayed
 *              Path                - Additional path string to be appended.
 *                                      (NULL if no extra path)
 *
 * RETURN:      acpi_status
 *
 * DESCRIPTION: Display full pathname of an object, DEBUG ONLY
 *
 ******************************************************************************/

void
acpi_ut_display_init_pathname(u8 type,
			      struct acpi_namespace_node *obj_handle,
			      char *path)
{
	acpi_status status;
	struct acpi_buffer buffer;

	ACPI_FUNCTION_ENTRY();

	/* Only print the path if the appropriate debug level is enabled */

	if (!(acpi_dbg_level & ACPI_LV_INIT_NAMES)) {
		return;
	}