660 lines
19 KiB
C
660 lines
19 KiB
C
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/*******************************************************************************
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*
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* Module Name: hwregs - Read/write access functions for the various ACPI
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* control and status registers.
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*
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******************************************************************************/
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/*
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* Copyright (C) 2000 - 2008, Intel Corp.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions, and the following disclaimer,
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* without modification.
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* 2. Redistributions in binary form must reproduce at minimum a disclaimer
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* substantially similar to the "NO WARRANTY" disclaimer below
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* ("Disclaimer") and any redistribution must be conditioned upon
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* including a substantially similar Disclaimer requirement for further
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* binary redistribution.
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* 3. Neither the names of the above-listed copyright holders nor the names
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* of any contributors may be used to endorse or promote products derived
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* from this software without specific prior written permission.
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*
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* Alternatively, this software may be distributed under the terms of the
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* GNU General Public License ("GPL") version 2 as published by the Free
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* Software Foundation.
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*
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* NO WARRANTY
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
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* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
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* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGES.
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*/
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#include <acpi/acpi.h>
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#include "accommon.h"
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#include "acnamesp.h"
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#include "acevents.h"
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#define _COMPONENT ACPI_HARDWARE
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ACPI_MODULE_NAME("hwregs")
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/* Local Prototypes */
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static acpi_status
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acpi_hw_read_multiple(u32 *value,
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struct acpi_generic_address *register_a,
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struct acpi_generic_address *register_b);
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static acpi_status
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acpi_hw_write_multiple(u32 value,
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struct acpi_generic_address *register_a,
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struct acpi_generic_address *register_b);
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_validate_register
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*
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* PARAMETERS: Reg - GAS register structure
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* max_bit_width - Max bit_width supported (32 or 64)
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* Address - Pointer to where the gas->address
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* is returned
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*
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* RETURN: Status
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*
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* DESCRIPTION: Validate the contents of a GAS register. Checks the GAS
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* pointer, Address, space_id, bit_width, and bit_offset.
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*
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******************************************************************************/
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acpi_status
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acpi_hw_validate_register(struct acpi_generic_address *reg,
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u8 max_bit_width, u64 *address)
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{
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/* Must have a valid pointer to a GAS structure */
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if (!reg) {
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return (AE_BAD_PARAMETER);
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}
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/*
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* Copy the target address. This handles possible alignment issues.
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* Address must not be null. A null address also indicates an optional
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* ACPI register that is not supported, so no error message.
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*/
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ACPI_MOVE_64_TO_64(address, ®->address);
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if (!(*address)) {
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return (AE_BAD_ADDRESS);
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}
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/* Validate the space_iD */
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if ((reg->space_id != ACPI_ADR_SPACE_SYSTEM_MEMORY) &&
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(reg->space_id != ACPI_ADR_SPACE_SYSTEM_IO)) {
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ACPI_ERROR((AE_INFO,
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"Unsupported address space: 0x%X", reg->space_id));
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return (AE_SUPPORT);
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}
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/* Validate the bit_width */
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if ((reg->bit_width != 8) &&
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(reg->bit_width != 16) &&
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(reg->bit_width != 32) && (reg->bit_width != max_bit_width)) {
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ACPI_ERROR((AE_INFO,
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"Unsupported register bit width: 0x%X",
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reg->bit_width));
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return (AE_SUPPORT);
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}
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/* Validate the bit_offset. Just a warning for now. */
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if (reg->bit_offset != 0) {
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ACPI_WARNING((AE_INFO,
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"Unsupported register bit offset: 0x%X",
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reg->bit_offset));
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}
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return (AE_OK);
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}
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_read
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*
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* PARAMETERS: Value - Where the value is returned
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* Reg - GAS register structure
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*
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* RETURN: Status
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*
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* DESCRIPTION: Read from either memory or IO space. This is a 32-bit max
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* version of acpi_read, used internally since the overhead of
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* 64-bit values is not needed.
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*
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* LIMITATIONS: <These limitations also apply to acpi_hw_write>
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* bit_width must be exactly 8, 16, or 32.
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* space_iD must be system_memory or system_iO.
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* bit_offset and access_width are currently ignored, as there has
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* not been a need to implement these.
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*
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******************************************************************************/
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acpi_status acpi_hw_read(u32 *value, struct acpi_generic_address *reg)
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{
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u64 address;
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acpi_status status;
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ACPI_FUNCTION_NAME(hw_read);
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/* Validate contents of the GAS register */
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status = acpi_hw_validate_register(reg, 32, &address);
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if (ACPI_FAILURE(status)) {
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return (status);
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}
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/* Initialize entire 32-bit return value to zero */
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*value = 0;
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/*
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* Two address spaces supported: Memory or IO. PCI_Config is
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* not supported here because the GAS structure is insufficient
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*/
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if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
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status = acpi_os_read_memory((acpi_physical_address)
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address, value, reg->bit_width);
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} else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
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status = acpi_hw_read_port((acpi_io_address)
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address, value, reg->bit_width);
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}
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ACPI_DEBUG_PRINT((ACPI_DB_IO,
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"Read: %8.8X width %2d from %8.8X%8.8X (%s)\n",
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*value, reg->bit_width, ACPI_FORMAT_UINT64(address),
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acpi_ut_get_region_name(reg->space_id)));
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return (status);
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}
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_write
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*
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* PARAMETERS: Value - Value to be written
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* Reg - GAS register structure
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*
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* RETURN: Status
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*
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* DESCRIPTION: Write to either memory or IO space. This is a 32-bit max
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* version of acpi_write, used internally since the overhead of
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* 64-bit values is not needed.
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*
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******************************************************************************/
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acpi_status acpi_hw_write(u32 value, struct acpi_generic_address *reg)
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{
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u64 address;
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acpi_status status;
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ACPI_FUNCTION_NAME(hw_write);
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/* Validate contents of the GAS register */
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status = acpi_hw_validate_register(reg, 32, &address);
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if (ACPI_FAILURE(status)) {
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return (status);
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}
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/*
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* Two address spaces supported: Memory or IO. PCI_Config is
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* not supported here because the GAS structure is insufficient
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*/
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if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
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status = acpi_os_write_memory((acpi_physical_address)
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address, value, reg->bit_width);
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} else { /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */
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status = acpi_hw_write_port((acpi_io_address)
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address, value, reg->bit_width);
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}
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ACPI_DEBUG_PRINT((ACPI_DB_IO,
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"Wrote: %8.8X width %2d to %8.8X%8.8X (%s)\n",
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value, reg->bit_width, ACPI_FORMAT_UINT64(address),
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acpi_ut_get_region_name(reg->space_id)));
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return (status);
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}
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/*******************************************************************************
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*
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* FUNCTION: acpi_hw_clear_acpi_status
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*
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* PARAMETERS: None
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*
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* RETURN: Status
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*
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* DESCRIPTION: Clears all fixed and general purpose status bits
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*
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******************************************************************************/
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acpi_status acpi_hw_clear_acpi_status(void)
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{
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acpi_status status;
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acpi_cpu_flags lock_flags = 0;
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ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
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ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %8.8X%8.8X\n",
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ACPI_BITMASK_ALL_FIXED_STATUS,
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ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address)));
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lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
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/* Clear the fixed events in PM1 A/B */
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status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
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ACPI_BITMASK_ALL_FIXED_STATUS);
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if (ACPI_FAILURE(status)) {
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goto unlock_and_exit;
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}
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/* Clear the GPE Bits in all GPE registers in all GPE blocks */
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status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block, NULL);
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unlock_and_exit:
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acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
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return_ACPI_STATUS(status);
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}
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/*******************************************************************************
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*
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* FUNCTION: acpi_hw_get_register_bit_mask
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*
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* PARAMETERS: register_id - Index of ACPI Register to access
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*
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* RETURN: The bitmask to be used when accessing the register
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*
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* DESCRIPTION: Map register_id into a register bitmask.
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*
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******************************************************************************/
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struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
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{
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ACPI_FUNCTION_ENTRY();
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if (register_id > ACPI_BITREG_MAX) {
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ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: %X",
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register_id));
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return (NULL);
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}
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return (&acpi_gbl_bit_register_info[register_id]);
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}
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_write_pm1_control
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*
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* PARAMETERS: pm1a_control - Value to be written to PM1A control
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* pm1b_control - Value to be written to PM1B control
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*
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* RETURN: Status
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*
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* DESCRIPTION: Write the PM1 A/B control registers. These registers are
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* different than than the PM1 A/B status and enable registers
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* in that different values can be written to the A/B registers.
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* Most notably, the SLP_TYP bits can be different, as per the
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* values returned from the _Sx predefined methods.
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*
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******************************************************************************/
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acpi_status acpi_hw_write_pm1_control(u32 pm1a_control, u32 pm1b_control)
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{
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acpi_status status;
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ACPI_FUNCTION_TRACE(hw_write_pm1_control);
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status =
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acpi_hw_write(pm1a_control, &acpi_gbl_FADT.xpm1a_control_block);
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if (ACPI_FAILURE(status)) {
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return_ACPI_STATUS(status);
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}
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if (acpi_gbl_FADT.xpm1b_control_block.address) {
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status =
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acpi_hw_write(pm1b_control,
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&acpi_gbl_FADT.xpm1b_control_block);
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}
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return_ACPI_STATUS(status);
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}
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_register_read
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*
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* PARAMETERS: register_id - ACPI Register ID
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* return_value - Where the register value is returned
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*
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* RETURN: Status and the value read.
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*
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* DESCRIPTION: Read from the specified ACPI register
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*
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******************************************************************************/
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acpi_status
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acpi_hw_register_read(u32 register_id, u32 * return_value)
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{
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u32 value = 0;
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acpi_status status;
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ACPI_FUNCTION_TRACE(hw_register_read);
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switch (register_id) {
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case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */
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status = acpi_hw_read_multiple(&value,
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&acpi_gbl_xpm1a_status,
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&acpi_gbl_xpm1b_status);
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break;
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case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access each */
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status = acpi_hw_read_multiple(&value,
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&acpi_gbl_xpm1a_enable,
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&acpi_gbl_xpm1b_enable);
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break;
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case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
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status = acpi_hw_read_multiple(&value,
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&acpi_gbl_FADT.
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xpm1a_control_block,
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&acpi_gbl_FADT.
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xpm1b_control_block);
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/*
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* Zero the write-only bits. From the ACPI specification, "Hardware
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* Write-Only Bits": "Upon reads to registers with write-only bits,
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* software masks out all write-only bits."
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*/
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value &= ~ACPI_PM1_CONTROL_WRITEONLY_BITS;
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break;
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case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
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status =
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acpi_hw_read(&value, &acpi_gbl_FADT.xpm2_control_block);
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break;
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case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
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status = acpi_hw_read(&value, &acpi_gbl_FADT.xpm_timer_block);
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break;
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case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
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status =
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acpi_hw_read_port(acpi_gbl_FADT.smi_command, &value, 8);
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break;
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default:
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ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
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status = AE_BAD_PARAMETER;
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break;
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}
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if (ACPI_SUCCESS(status)) {
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*return_value = value;
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}
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return_ACPI_STATUS(status);
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}
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/******************************************************************************
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*
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* FUNCTION: acpi_hw_register_write
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*
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* PARAMETERS: register_id - ACPI Register ID
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* Value - The value to write
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*
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* RETURN: Status
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*
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* DESCRIPTION: Write to the specified ACPI register
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*
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* NOTE: In accordance with the ACPI specification, this function automatically
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* preserves the value of the following bits, meaning that these bits cannot be
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* changed via this interface:
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*
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* PM1_CONTROL[0] = SCI_EN
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* PM1_CONTROL[9]
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* PM1_STATUS[11]
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*
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* ACPI References:
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* 1) Hardware Ignored Bits: When software writes to a register with ignored
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* bit fields, it preserves the ignored bit fields
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* 2) SCI_EN: OSPM always preserves this bit position
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*
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******************************************************************************/
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acpi_status acpi_hw_register_write(u32 register_id, u32 value)
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{
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acpi_status status;
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u32 read_value;
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ACPI_FUNCTION_TRACE(hw_register_write);
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switch (register_id) {
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case ACPI_REGISTER_PM1_STATUS: /* PM1 A/B: 16-bit access each */
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/*
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* Handle the "ignored" bit in PM1 Status. According to the ACPI
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* specification, ignored bits are to be preserved when writing.
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* Normally, this would mean a read/modify/write sequence. However,
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* preserving a bit in the status register is different. Writing a
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* one clears the status, and writing a zero preserves the status.
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* Therefore, we must always write zero to the ignored bit.
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*
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* This behavior is clarified in the ACPI 4.0 specification.
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*/
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value &= ~ACPI_PM1_STATUS_PRESERVED_BITS;
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status = acpi_hw_write_multiple(value,
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&acpi_gbl_xpm1a_status,
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&acpi_gbl_xpm1b_status);
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break;
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case ACPI_REGISTER_PM1_ENABLE: /* PM1 A/B: 16-bit access */
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status = acpi_hw_write_multiple(value,
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&acpi_gbl_xpm1a_enable,
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&acpi_gbl_xpm1b_enable);
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break;
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case ACPI_REGISTER_PM1_CONTROL: /* PM1 A/B: 16-bit access each */
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/*
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* Perform a read first to preserve certain bits (per ACPI spec)
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* Note: This includes SCI_EN, we never want to change this bit
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*/
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status = acpi_hw_read_multiple(&read_value,
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&acpi_gbl_FADT.
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xpm1a_control_block,
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&acpi_gbl_FADT.
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xpm1b_control_block);
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if (ACPI_FAILURE(status)) {
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goto exit;
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}
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/* Insert the bits to be preserved */
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ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
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read_value);
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/* Now we can write the data */
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status = acpi_hw_write_multiple(value,
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&acpi_gbl_FADT.
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xpm1a_control_block,
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&acpi_gbl_FADT.
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xpm1b_control_block);
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break;
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case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
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/*
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* For control registers, all reserved bits must be preserved,
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* as per the ACPI spec.
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*/
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status =
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acpi_hw_read(&read_value,
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&acpi_gbl_FADT.xpm2_control_block);
|
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if (ACPI_FAILURE(status)) {
|
|
goto exit;
|
|
}
|
|
|
|
/* Insert the bits to be preserved */
|
|
|
|
ACPI_INSERT_BITS(value, ACPI_PM2_CONTROL_PRESERVED_BITS,
|
|
read_value);
|
|
|
|
status =
|
|
acpi_hw_write(value, &acpi_gbl_FADT.xpm2_control_block);
|
|
break;
|
|
|
|
case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
|
|
|
|
status = acpi_hw_write(value, &acpi_gbl_FADT.xpm_timer_block);
|
|
break;
|
|
|
|
case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
|
|
|
|
/* SMI_CMD is currently always in IO space */
|
|
|
|
status =
|
|
acpi_hw_write_port(acpi_gbl_FADT.smi_command, value, 8);
|
|
break;
|
|
|
|
default:
|
|
ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
|
|
status = AE_BAD_PARAMETER;
|
|
break;
|
|
}
|
|
|
|
exit:
|
|
return_ACPI_STATUS(status);
|
|
}
|
|
|
|
/******************************************************************************
|
|
*
|
|
* FUNCTION: acpi_hw_read_multiple
|
|
*
|
|
* PARAMETERS: Value - Where the register value is returned
|
|
* register_a - First ACPI register (required)
|
|
* register_b - Second ACPI register (optional)
|
|
*
|
|
* RETURN: Status
|
|
*
|
|
* DESCRIPTION: Read from the specified two-part ACPI register (such as PM1 A/B)
|
|
*
|
|
******************************************************************************/
|
|
|
|
static acpi_status
|
|
acpi_hw_read_multiple(u32 *value,
|
|
struct acpi_generic_address *register_a,
|
|
struct acpi_generic_address *register_b)
|
|
{
|
|
u32 value_a = 0;
|
|
u32 value_b = 0;
|
|
acpi_status status;
|
|
|
|
/* The first register is always required */
|
|
|
|
status = acpi_hw_read(&value_a, register_a);
|
|
if (ACPI_FAILURE(status)) {
|
|
return (status);
|
|
}
|
|
|
|
/* Second register is optional */
|
|
|
|
if (register_b->address) {
|
|
status = acpi_hw_read(&value_b, register_b);
|
|
if (ACPI_FAILURE(status)) {
|
|
return (status);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* OR the two return values together. No shifting or masking is necessary,
|
|
* because of how the PM1 registers are defined in the ACPI specification:
|
|
*
|
|
* "Although the bits can be split between the two register blocks (each
|
|
* register block has a unique pointer within the FADT), the bit positions
|
|
* are maintained. The register block with unimplemented bits (that is,
|
|
* those implemented in the other register block) always returns zeros,
|
|
* and writes have no side effects"
|
|
*/
|
|
*value = (value_a | value_b);
|
|
return (AE_OK);
|
|
}
|
|
|
|
/******************************************************************************
|
|
*
|
|
* FUNCTION: acpi_hw_write_multiple
|
|
*
|
|
* PARAMETERS: Value - The value to write
|
|
* register_a - First ACPI register (required)
|
|
* register_b - Second ACPI register (optional)
|
|
*
|
|
* RETURN: Status
|
|
*
|
|
* DESCRIPTION: Write to the specified two-part ACPI register (such as PM1 A/B)
|
|
*
|
|
******************************************************************************/
|
|
|
|
static acpi_status
|
|
acpi_hw_write_multiple(u32 value,
|
|
struct acpi_generic_address *register_a,
|
|
struct acpi_generic_address *register_b)
|
|
{
|
|
acpi_status status;
|
|
|
|
/* The first register is always required */
|
|
|
|
status = acpi_hw_write(value, register_a);
|
|
if (ACPI_FAILURE(status)) {
|
|
return (status);
|
|
}
|
|
|
|
/*
|
|
* Second register is optional
|
|
*
|
|
* No bit shifting or clearing is necessary, because of how the PM1
|
|
* registers are defined in the ACPI specification:
|
|
*
|
|
* "Although the bits can be split between the two register blocks (each
|
|
* register block has a unique pointer within the FADT), the bit positions
|
|
* are maintained. The register block with unimplemented bits (that is,
|
|
* those implemented in the other register block) always returns zeros,
|
|
* and writes have no side effects"
|
|
*/
|
|
if (register_b->address) {
|
|
status = acpi_hw_write(value, register_b);
|
|
}
|
|
|
|
return (status);
|
|
}
|