drivers/acpi/acpica/exregion.c - linux - Git at Google

 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
 /******************************************************************************
  *
  * Module Name: exregion - ACPI default op_region (address space) handlers
  *
  * Copyright (C) 2000 - 2023, Intel Corp.
  *
  *****************************************************************************/

 #include <acpi/acpi.h>
 #include "accommon.h"
 #include "acinterp.h"

 #define _COMPONENT          ACPI_EXECUTER
 ACPI_MODULE_NAME("exregion")

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_system_memory_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the System Memory address space (Op Region)
  *
  ******************************************************************************/
 acpi_status
 acpi_ex_system_memory_space_handler(u32 function,
 				    acpi_physical_address address,
 				    u32 bit_width,
 				    u64 *value,
 				    void *handler_context, void *region_context)
 {
 	acpi_status status = AE_OK;
 	void *logical_addr_ptr = NULL;
 	struct acpi_mem_space_context *mem_info = region_context;
 	struct acpi_mem_mapping *mm = mem_info->cur_mm;
 	u32 length;
 	acpi_size map_length;
 #ifdef ACPI_MISALIGNMENT_NOT_SUPPORTED
 	u32 remainder;
 #endif

 	ACPI_FUNCTION_TRACE(ex_system_memory_space_handler);

 	/* Validate and translate the bit width */

 	switch (bit_width) {
 	case 8:

 		length = 1;
 		break;

 	case 16:

 		length = 2;
 		break;

 	case 32:

 		length = 4;
 		break;

 	case 64:

 		length = 8;
 		break;

 	default:

 		ACPI_ERROR((AE_INFO, "Invalid SystemMemory width %u",
 			    bit_width));
 		return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
 	}

 #ifdef ACPI_MISALIGNMENT_NOT_SUPPORTED
 	/*
 	 * Hardware does not support non-aligned data transfers, we must verify
 	 * the request.
 	 */
 	(void)acpi_ut_short_divide((u64) address, length, NULL, &remainder);
 	if (remainder != 0) {
 		return_ACPI_STATUS(AE_AML_ALIGNMENT);
 	}
 #endif

 	/*
 	 * Does the request fit into the cached memory mapping?
 	 * Is 1) Address below the current mapping? OR
 	 *    2) Address beyond the current mapping?
 	 */
 	if (!mm || (address < mm->physical_address) ||
 	    ((u64) address + length > (u64) mm->physical_address + mm->length)) {
 		/*
 		 * The request cannot be resolved by the current memory mapping.
 		 *
 		 * Look for an existing saved mapping covering the address range
 		 * at hand.  If found, save it as the current one and carry out
 		 * the access.
 		 */
 		for (mm = mem_info->first_mm; mm; mm = mm->next_mm) {
 			if (mm == mem_info->cur_mm)
 				continue;

 			if (address < mm->physical_address)
 				continue;

 			if ((u64) address + length >
 					(u64) mm->physical_address + mm->length)
 				continue;

 			mem_info->cur_mm = mm;
 			goto access;
 		}

 		/* Create a new mappings list entry */
 		mm = ACPI_ALLOCATE_ZEROED(sizeof(*mm));
 		if (!mm) {
 			ACPI_ERROR((AE_INFO,
 				    "Unable to save memory mapping at 0x%8.8X%8.8X, size %u",
 				    ACPI_FORMAT_UINT64(address), length));
 			return_ACPI_STATUS(AE_NO_MEMORY);
 		}

 		/*
 		 * October 2009: Attempt to map from the requested address to the
 		 * end of the region. However, we will never map more than one
 		 * page, nor will we cross a page boundary.
 		 */
 		map_length = (acpi_size)
 		    ((mem_info->address + mem_info->length) - address);

 		if (map_length > ACPI_DEFAULT_PAGE_SIZE)
 			map_length = ACPI_DEFAULT_PAGE_SIZE;

 		/* Create a new mapping starting at the address given */

 		logical_addr_ptr = acpi_os_map_memory(address, map_length);
 		if (!logical_addr_ptr) {
 			ACPI_ERROR((AE_INFO,
 				    "Could not map memory at 0x%8.8X%8.8X, size %u",
 				    ACPI_FORMAT_UINT64(address),
 				    (u32)map_length));
 			ACPI_FREE(mm);
 			return_ACPI_STATUS(AE_NO_MEMORY);
 		}

 		/* Save the physical address and mapping size */

 		mm->logical_address = logical_addr_ptr;
 		mm->physical_address = address;
 		mm->length = map_length;

 		/*
 		 * Add the new entry to the mappigs list and save it as the
 		 * current mapping.
 		 */
 		mm->next_mm = mem_info->first_mm;
 		mem_info->first_mm = mm;

 		mem_info->cur_mm = mm;
 	}

 access:
 	/*
 	 * Generate a logical pointer corresponding to the address we want to
 	 * access
 	 */
 	logical_addr_ptr = mm->logical_address +
 		((u64) address - (u64) mm->physical_address);

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 			  "System-Memory (width %u) R/W %u Address=%8.8X%8.8X\n",
 			  bit_width, function, ACPI_FORMAT_UINT64(address)));

 	/*
 	 * Perform the memory read or write
 	 *
 	 * Note: For machines that do not support non-aligned transfers, the target
 	 * address was checked for alignment above. We do not attempt to break the
 	 * transfer up into smaller (byte-size) chunks because the AML specifically
 	 * asked for a transfer width that the hardware may require.
 	 */
 	switch (function) {
 	case ACPI_READ:

 		*value = 0;
 		switch (bit_width) {
 		case 8:

 			*value = (u64)ACPI_GET8(logical_addr_ptr);
 			break;

 		case 16:

 			*value = (u64)ACPI_GET16(logical_addr_ptr);
 			break;

 		case 32:

 			*value = (u64)ACPI_GET32(logical_addr_ptr);
 			break;

 		case 64:

 			*value = (u64)ACPI_GET64(logical_addr_ptr);
 			break;

 		default:

 			/* bit_width was already validated */

 			break;
 		}
 		break;

 	case ACPI_WRITE:

 		switch (bit_width) {
 		case 8:

 			ACPI_SET8(logical_addr_ptr, *value);
 			break;

 		case 16:

 			ACPI_SET16(logical_addr_ptr, *value);
 			break;

 		case 32:

 			ACPI_SET32(logical_addr_ptr, *value);
 			break;

 		case 64:

 			ACPI_SET64(logical_addr_ptr, *value);
 			break;

 		default:

 			/* bit_width was already validated */

 			break;
 		}
 		break;

 	default:

 		status = AE_BAD_PARAMETER;
 		break;
 	}

 	return_ACPI_STATUS(status);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_system_io_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the System IO address space (Op Region)
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_system_io_space_handler(u32 function,
 				acpi_physical_address address,
 				u32 bit_width,
 				u64 *value,
 				void *handler_context, void *region_context)
 {
 	acpi_status status = AE_OK;
 	u32 value32;

 	ACPI_FUNCTION_TRACE(ex_system_io_space_handler);

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 			  "System-IO (width %u) R/W %u Address=%8.8X%8.8X\n",
 			  bit_width, function, ACPI_FORMAT_UINT64(address)));

 	/* Decode the function parameter */

 	switch (function) {
 	case ACPI_READ:

 		status = acpi_hw_read_port((acpi_io_address)address,
 					   &value32, bit_width);
 		*value = value32;
 		break;

 	case ACPI_WRITE:

 		status = acpi_hw_write_port((acpi_io_address)address,
 					    (u32)*value, bit_width);
 		break;

 	default:

 		status = AE_BAD_PARAMETER;
 		break;
 	}

 	return_ACPI_STATUS(status);
 }

 #ifdef ACPI_PCI_CONFIGURED
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_pci_config_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the PCI Config address space (Op Region)
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_pci_config_space_handler(u32 function,
 				 acpi_physical_address address,
 				 u32 bit_width,
 				 u64 *value,
 				 void *handler_context, void *region_context)
 {
 	acpi_status status = AE_OK;
 	struct acpi_pci_id *pci_id;
 	u16 pci_register;

 	ACPI_FUNCTION_TRACE(ex_pci_config_space_handler);

 	/*
 	 *  The arguments to acpi_os(Read|Write)pci_configuration are:
 	 *
 	 *  pci_segment is the PCI bus segment range 0-31
 	 *  pci_bus     is the PCI bus number range 0-255
 	 *  pci_device  is the PCI device number range 0-31
 	 *  pci_function is the PCI device function number
 	 *  pci_register is the Config space register range 0-255 bytes
 	 *
 	 *  value - input value for write, output address for read
 	 *
 	 */
 	pci_id = (struct acpi_pci_id *)region_context;
 	pci_register = (u16) (u32) address;

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
 			  "Pci-Config %u (%u) Seg(%04x) Bus(%04x) "
 			  "Dev(%04x) Func(%04x) Reg(%04x)\n",
 			  function, bit_width, pci_id->segment, pci_id->bus,
 			  pci_id->device, pci_id->function, pci_register));

 	switch (function) {
 	case ACPI_READ:

 		*value = 0;
 		status =
 		    acpi_os_read_pci_configuration(pci_id, pci_register, value,
 						   bit_width);
 		break;

 	case ACPI_WRITE:

 		status =
 		    acpi_os_write_pci_configuration(pci_id, pci_register,
 						    *value, bit_width);
 		break;

 	default:

 		status = AE_BAD_PARAMETER;
 		break;
 	}

 	return_ACPI_STATUS(status);
 }
 #endif

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_cmos_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the CMOS address space (Op Region)
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_cmos_space_handler(u32 function,
 			   acpi_physical_address address,
 			   u32 bit_width,
 			   u64 *value,
 			   void *handler_context, void *region_context)
 {
 	acpi_status status = AE_OK;

 	ACPI_FUNCTION_TRACE(ex_cmos_space_handler);

 	return_ACPI_STATUS(status);
 }

 #ifdef ACPI_PCI_CONFIGURED
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_pci_bar_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the PCI bar_target address space (Op Region)
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_pci_bar_space_handler(u32 function,
 			      acpi_physical_address address,
 			      u32 bit_width,
 			      u64 *value,
 			      void *handler_context, void *region_context)
 {
 	acpi_status status = AE_OK;

 	ACPI_FUNCTION_TRACE(ex_pci_bar_space_handler);

 	return_ACPI_STATUS(status);
 }
 #endif

 /*******************************************************************************
  *
  * FUNCTION:    acpi_ex_data_table_space_handler
  *
  * PARAMETERS:  function            - Read or Write operation
  *              address             - Where in the space to read or write
  *              bit_width           - Field width in bits (8, 16, or 32)
  *              value               - Pointer to in or out value
  *              handler_context     - Pointer to Handler's context
  *              region_context      - Pointer to context specific to the
  *                                    accessed region
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Handler for the Data Table address space (Op Region)
  *
  ******************************************************************************/

 acpi_status
 acpi_ex_data_table_space_handler(u32 function,
 				 acpi_physical_address address,
 				 u32 bit_width,
 				 u64 *value,
 				 void *handler_context, void *region_context)
 {
 	struct acpi_data_table_mapping *mapping;
 	char *pointer;

 	ACPI_FUNCTION_TRACE(ex_data_table_space_handler);

 	mapping = (struct acpi_data_table_mapping *) region_context;
 	pointer = ACPI_CAST_PTR(char, mapping->pointer) +
 	    (address - ACPI_PTR_TO_PHYSADDR(mapping->pointer));

 	/*
 	 * Perform the memory read or write. The bit_width was already
 	 * validated.
 	 */
 	switch (function) {
 	case ACPI_READ:

 		memcpy(ACPI_CAST_PTR(char, value), pointer,
 		       ACPI_DIV_8(bit_width));
 		break;

 	case ACPI_WRITE:

 		memcpy(pointer, ACPI_CAST_PTR(char, value),
 		       ACPI_DIV_8(bit_width));
 		break;

 	default:

 		return_ACPI_STATUS(AE_BAD_PARAMETER);
 	}

 	return_ACPI_STATUS(AE_OK);
 }
	// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
	/******************************************************************************
	*
	* Module Name: exregion - ACPI default op_region (address space) handlers
	*
	* Copyright (C) 2000 - 2023, Intel Corp.
	*
	*****************************************************************************/

	#include <acpi/acpi.h>
	#include "accommon.h"
	#include "acinterp.h"

	#define _COMPONENT ACPI_EXECUTER
	ACPI_MODULE_NAME("exregion")

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_system_memory_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the System Memory address space (Op Region)
	*
	******************************************************************************/
	acpi_status
	acpi_ex_system_memory_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	acpi_status status = AE_OK;
	void *logical_addr_ptr = NULL;
	struct acpi_mem_space_context *mem_info = region_context;
	struct acpi_mem_mapping *mm = mem_info->cur_mm;
	u32 length;
	acpi_size map_length;
	#ifdef ACPI_MISALIGNMENT_NOT_SUPPORTED
	u32 remainder;
	#endif

	ACPI_FUNCTION_TRACE(ex_system_memory_space_handler);

	/* Validate and translate the bit width */

	switch (bit_width) {
	case 8:

	length = 1;
	break;

	case 16:

	length = 2;
	break;

	case 32:

	length = 4;
	break;

	case 64:

	length = 8;
	break;

	default:

	ACPI_ERROR((AE_INFO, "Invalid SystemMemory width %u",
	bit_width));
	return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
	}

	#ifdef ACPI_MISALIGNMENT_NOT_SUPPORTED
	/*
	* Hardware does not support non-aligned data transfers, we must verify
	* the request.
	*/
	(void)acpi_ut_short_divide((u64) address, length, NULL, &remainder);
	if (remainder != 0) {
	return_ACPI_STATUS(AE_AML_ALIGNMENT);
	}
	#endif

	/*
	* Does the request fit into the cached memory mapping?
	* Is 1) Address below the current mapping? OR
	* 2) Address beyond the current mapping?
	*/
	if (!mm \|\| (address < mm->physical_address) \|\|
	((u64) address + length > (u64) mm->physical_address + mm->length)) {
	/*
	* The request cannot be resolved by the current memory mapping.
	*
	* Look for an existing saved mapping covering the address range
	* at hand. If found, save it as the current one and carry out
	* the access.
	*/
	for (mm = mem_info->first_mm; mm; mm = mm->next_mm) {
	if (mm == mem_info->cur_mm)
	continue;

	if (address < mm->physical_address)
	continue;

	if ((u64) address + length >
	(u64) mm->physical_address + mm->length)
	continue;

	mem_info->cur_mm = mm;
	goto access;
	}

	/* Create a new mappings list entry */
	mm = ACPI_ALLOCATE_ZEROED(sizeof(*mm));
	if (!mm) {
	ACPI_ERROR((AE_INFO,
	"Unable to save memory mapping at 0x%8.8X%8.8X, size %u",
	ACPI_FORMAT_UINT64(address), length));
	return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/*
	* October 2009: Attempt to map from the requested address to the
	* end of the region. However, we will never map more than one
	* page, nor will we cross a page boundary.
	*/
	map_length = (acpi_size)
	((mem_info->address + mem_info->length) - address);

	if (map_length > ACPI_DEFAULT_PAGE_SIZE)
	map_length = ACPI_DEFAULT_PAGE_SIZE;

	/* Create a new mapping starting at the address given */

	logical_addr_ptr = acpi_os_map_memory(address, map_length);
	if (!logical_addr_ptr) {
	ACPI_ERROR((AE_INFO,
	"Could not map memory at 0x%8.8X%8.8X, size %u",
	ACPI_FORMAT_UINT64(address),
	(u32)map_length));
	ACPI_FREE(mm);
	return_ACPI_STATUS(AE_NO_MEMORY);
	}

	/* Save the physical address and mapping size */

	mm->logical_address = logical_addr_ptr;
	mm->physical_address = address;
	mm->length = map_length;

	/*
	* Add the new entry to the mappigs list and save it as the
	* current mapping.
	*/
	mm->next_mm = mem_info->first_mm;
	mem_info->first_mm = mm;

	mem_info->cur_mm = mm;
	}

	access:
	/*
	* Generate a logical pointer corresponding to the address we want to
	* access
	*/
	logical_addr_ptr = mm->logical_address +
	((u64) address - (u64) mm->physical_address);

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"System-Memory (width %u) R/W %u Address=%8.8X%8.8X\n",
	bit_width, function, ACPI_FORMAT_UINT64(address)));

	/*
	* Perform the memory read or write
	*
	* Note: For machines that do not support non-aligned transfers, the target
	* address was checked for alignment above. We do not attempt to break the
	* transfer up into smaller (byte-size) chunks because the AML specifically
	* asked for a transfer width that the hardware may require.
	*/
	switch (function) {
	case ACPI_READ:

	*value = 0;
	switch (bit_width) {
	case 8:

	*value = (u64)ACPI_GET8(logical_addr_ptr);
	break;

	case 16:

	*value = (u64)ACPI_GET16(logical_addr_ptr);
	break;

	case 32:

	*value = (u64)ACPI_GET32(logical_addr_ptr);
	break;

	case 64:

	*value = (u64)ACPI_GET64(logical_addr_ptr);
	break;

	default:

	/* bit_width was already validated */

	break;
	}
	break;

	case ACPI_WRITE:

	switch (bit_width) {
	case 8:

	ACPI_SET8(logical_addr_ptr, *value);
	break;

	case 16:

	ACPI_SET16(logical_addr_ptr, *value);
	break;

	case 32:

	ACPI_SET32(logical_addr_ptr, *value);
	break;

	case 64:

	ACPI_SET64(logical_addr_ptr, *value);
	break;

	default:

	/* bit_width was already validated */

	break;
	}
	break;

	default:

	status = AE_BAD_PARAMETER;
	break;
	}

	return_ACPI_STATUS(status);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_system_io_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the System IO address space (Op Region)
	*
	******************************************************************************/

	acpi_status
	acpi_ex_system_io_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	acpi_status status = AE_OK;
	u32 value32;

	ACPI_FUNCTION_TRACE(ex_system_io_space_handler);

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"System-IO (width %u) R/W %u Address=%8.8X%8.8X\n",
	bit_width, function, ACPI_FORMAT_UINT64(address)));

	/* Decode the function parameter */

	switch (function) {
	case ACPI_READ:

	status = acpi_hw_read_port((acpi_io_address)address,
	&value32, bit_width);
	*value = value32;
	break;

	case ACPI_WRITE:

	status = acpi_hw_write_port((acpi_io_address)address,
	(u32)*value, bit_width);
	break;

	default:

	status = AE_BAD_PARAMETER;
	break;
	}

	return_ACPI_STATUS(status);
	}

	#ifdef ACPI_PCI_CONFIGURED
	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_pci_config_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the PCI Config address space (Op Region)
	*
	******************************************************************************/

	acpi_status
	acpi_ex_pci_config_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	acpi_status status = AE_OK;
	struct acpi_pci_id *pci_id;
	u16 pci_register;

	ACPI_FUNCTION_TRACE(ex_pci_config_space_handler);

	/*
	* The arguments to acpi_os(Read\|Write)pci_configuration are:
	*
	* pci_segment is the PCI bus segment range 0-31
	* pci_bus is the PCI bus number range 0-255
	* pci_device is the PCI device number range 0-31
	* pci_function is the PCI device function number
	* pci_register is the Config space register range 0-255 bytes
	*
	* value - input value for write, output address for read
	*
	*/
	pci_id = (struct acpi_pci_id *)region_context;
	pci_register = (u16) (u32) address;

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
	"Pci-Config %u (%u) Seg(%04x) Bus(%04x) "
	"Dev(%04x) Func(%04x) Reg(%04x)\n",
	function, bit_width, pci_id->segment, pci_id->bus,
	pci_id->device, pci_id->function, pci_register));

	switch (function) {
	case ACPI_READ:

	*value = 0;
	status =
	acpi_os_read_pci_configuration(pci_id, pci_register, value,
	bit_width);
	break;

	case ACPI_WRITE:

	status =
	acpi_os_write_pci_configuration(pci_id, pci_register,
	*value, bit_width);
	break;

	default:

	status = AE_BAD_PARAMETER;
	break;
	}

	return_ACPI_STATUS(status);
	}
	#endif

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_cmos_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the CMOS address space (Op Region)
	*
	******************************************************************************/

	acpi_status
	acpi_ex_cmos_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(ex_cmos_space_handler);

	return_ACPI_STATUS(status);
	}

	#ifdef ACPI_PCI_CONFIGURED
	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_pci_bar_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the PCI bar_target address space (Op Region)
	*
	******************************************************************************/

	acpi_status
	acpi_ex_pci_bar_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	acpi_status status = AE_OK;

	ACPI_FUNCTION_TRACE(ex_pci_bar_space_handler);

	return_ACPI_STATUS(status);
	}
	#endif

	/*******************************************************************************
	*
	* FUNCTION: acpi_ex_data_table_space_handler
	*
	* PARAMETERS: function - Read or Write operation
	* address - Where in the space to read or write
	* bit_width - Field width in bits (8, 16, or 32)
	* value - Pointer to in or out value
	* handler_context - Pointer to Handler's context
	* region_context - Pointer to context specific to the
	* accessed region
	*
	* RETURN: Status
	*
	* DESCRIPTION: Handler for the Data Table address space (Op Region)
	*
	******************************************************************************/

	acpi_status
	acpi_ex_data_table_space_handler(u32 function,
	acpi_physical_address address,
	u32 bit_width,
	u64 *value,
	void handler_context, void region_context)
	{
	struct acpi_data_table_mapping *mapping;
	char *pointer;

	ACPI_FUNCTION_TRACE(ex_data_table_space_handler);

	mapping = (struct acpi_data_table_mapping *) region_context;
	pointer = ACPI_CAST_PTR(char, mapping->pointer) +
	(address - ACPI_PTR_TO_PHYSADDR(mapping->pointer));

	/*
	* Perform the memory read or write. The bit_width was already
	* validated.
	*/
	switch (function) {
	case ACPI_READ:

	memcpy(ACPI_CAST_PTR(char, value), pointer,
	ACPI_DIV_8(bit_width));
	break;

	case ACPI_WRITE:

	memcpy(pointer, ACPI_CAST_PTR(char, value),
	ACPI_DIV_8(bit_width));
	break;

	default:

	return_ACPI_STATUS(AE_BAD_PARAMETER);
	}

	return_ACPI_STATUS(AE_OK);
	}