/*******************************************************************************
*
* Module Name: hwregs - Read/write access functions for the various ACPI
* control and status registers.
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2006, 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 <acpi/acpi.h>
#include <acpi/acnamesp.h>
#include <acpi/acevents.h>
#define _COMPONENT ACPI_HARDWARE
ACPI_MODULE_NAME("hwregs")
/*******************************************************************************
*
* FUNCTION: acpi_hw_clear_acpi_status
*
* PARAMETERS: Flags - Lock the hardware or not
*
* RETURN: none
*
* DESCRIPTION: Clears all fixed and general purpose status bits
* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
*
* NOTE: TBD: Flags parameter is obsolete, to be removed
*
******************************************************************************/
acpi_status acpi_hw_clear_acpi_status(u32 flags)
{
acpi_status status;
acpi_cpu_flags lock_flags = 0;
ACPI_FUNCTION_TRACE(hw_clear_acpi_status);
ACPI_DEBUG_PRINT((ACPI_DB_IO, "About to write %04X to %04X\n",
ACPI_BITMASK_ALL_FIXED_STATUS,
(u16) acpi_gbl_FADT.xpm1a_event_block.address));
lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_STATUS,
ACPI_BITMASK_ALL_FIXED_STATUS);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* Clear the fixed events */
if (acpi_gbl_FADT.xpm1b_event_block.address) {
status =
acpi_hw_low_level_write(16, ACPI_BITMASK_ALL_FIXED_STATUS,
&acpi_gbl_FADT.xpm1b_event_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
}
/* Clear the GPE Bits in all GPE registers in all GPE blocks */
status = acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block);
unlock_and_exit:
acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_get_sleep_type_data
*
* PARAMETERS: sleep_state - Numeric sleep state
* *sleep_type_a - Where SLP_TYPa is returned
* *sleep_type_b - Where SLP_TYPb is returned
*
* RETURN: Status - ACPI status
*
* DESCRIPTION: Obtain the SLP_TYPa and SLP_TYPb values for the requested sleep
* state.
*
******************************************************************************/
acpi_status
acpi_get_sleep_type_data(u8 sleep_state, u8 * sleep_type_a, u8 * sleep_type_b)
{
acpi_status status = AE_OK;
struct acpi_evaluate_info *info;
ACPI_FUNCTION_TRACE(acpi_get_sleep_type_data);
/* Validate parameters */
if ((sleep_state > ACPI_S_STATES_MAX) || !sleep_type_a || !sleep_type_b) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Allocate the evaluation information block */
info = ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_evaluate_info));
if (!info) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
info->pathname =
ACPI_CAST_PTR(char, acpi_gbl_sleep_state_names[sleep_state]);
/* Evaluate the namespace object containing the values for this state */
status = acpi_ns_evaluate(info);
if (ACPI_FAILURE(status)) {
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"%s while evaluating SleepState [%s]\n",
acpi_format_exception(status),
info->pathname));
goto cleanup;
}
/* Must have a return object */
if (!info->return_object) {
ACPI_ERROR((AE_INFO, "No Sleep State object returned from [%s]",
info->pathname));
status = AE_NOT_EXIST;
}
/* It must be of type Package */
else if (ACPI_GET_OBJECT_TYPE(info->return_object) != ACPI_TYPE_PACKAGE) {
ACPI_ERROR((AE_INFO,
"Sleep State return object is not a Package"));
status = AE_AML_OPERAND_TYPE;
}
/*
* The package must have at least two elements. NOTE (March 2005): This
* goes against the current ACPI spec which defines this object as a
* package with one encoded DWORD element. However, existing practice
* by BIOS vendors seems to be to have 2 or more elements, at least
* one per sleep type (A/B).
*/
else if (info->return_object->package.count < 2) {
ACPI_ERROR((AE_INFO,
"Sleep State return package does not have at least two elements"));
status = AE_AML_NO_OPERAND;
}
/* The first two elements must both be of type Integer */
else if ((ACPI_GET_OBJECT_TYPE(info->return_object->package.elements[0])
!= ACPI_TYPE_INTEGER) ||
(ACPI_GET_OBJECT_TYPE(info->return_object->package.elements[1])
!= ACPI_TYPE_INTEGER)) {
ACPI_ERROR((AE_INFO,
"Sleep State return package elements are not both Integers (%s, %s)",
acpi_ut_get_object_type_name(info->return_object->
package.elements[0]),
acpi_ut_get_object_type_name(info->return_object->
package.elements[1])));
status = AE_AML_OPERAND_TYPE;
} else {
/* Valid _Sx_ package size, type, and value */
*sleep_type_a = (u8)
(info->return_object->package.elements[0])->integer.value;
*sleep_type_b = (u8)
(info->return_object->package.elements[1])->integer.value;
}
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"While evaluating SleepState [%s], bad Sleep object %p type %s",
info->pathname, info->return_object,
acpi_ut_get_object_type_name(info->
return_object)));
}
acpi_ut_remove_reference(info->return_object);
cleanup:
ACPI_FREE(info);
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_get_sleep_type_data)
/*******************************************************************************
*
* FUNCTION: acpi_hw_get_register_bit_mask
*
* PARAMETERS: register_id - Index of ACPI Register to access
*
* RETURN: The bitmask to be used when accessing the register
*
* DESCRIPTION: Map register_id into a register bitmask.
*
******************************************************************************/
struct acpi_bit_register_info *acpi_hw_get_bit_register_info(u32 register_id)
{
ACPI_FUNCTION_ENTRY();
if (register_id > ACPI_BITREG_MAX) {
ACPI_ERROR((AE_INFO, "Invalid BitRegister ID: %X",
register_id));
return (NULL);
}
return (&acpi_gbl_bit_register_info[register_id]);
}
/*******************************************************************************
*
* FUNCTION: acpi_get_register
*
* PARAMETERS: register_id - ID of ACPI bit_register to access
* return_value - Value that was read from the register
* Flags - Lock the hardware or not
*
* RETURN: Status and the value read from specified Register. Value
* returned is normalized to bit0 (is shifted all the way right)
*
* DESCRIPTION: ACPI bit_register read function.
*
* NOTE: TBD: Flags parameter is obsolete, to be removed
*
******************************************************************************/
acpi_status acpi_get_register(u32 register_id, u32 * return_value, u32 flags)
{
u32 register_value = 0;
struct acpi_bit_register_info *bit_reg_info;
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_get_register);
/* Get the info structure corresponding to the requested ACPI Register */
bit_reg_info = acpi_hw_get_bit_register_info(register_id);
if (!bit_reg_info) {
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
/* Read from the register */
status = acpi_hw_register_read(ACPI_MTX_LOCK,
bit_reg_info->parent_register,
®ister_value);
if (ACPI_SUCCESS(status)) {
/* Normalize the value that was read */
register_value =
((register_value & bit_reg_info->access_bit_mask)
>> bit_reg_info->bit_position);
*return_value = register_value;
ACPI_DEBUG_PRINT((ACPI_DB_IO, "Read value %8.8X register %X\n",
register_value,
bit_reg_info->parent_register));
}
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_get_register)
/*******************************************************************************
*
* FUNCTION: acpi_set_register
*
* PARAMETERS: register_id - ID of ACPI bit_register to access
* Value - (only used on write) value to write to the
* Register, NOT pre-normalized to the bit pos
* Flags - Lock the hardware or not
*
* RETURN: Status
*
* DESCRIPTION: ACPI Bit Register write function.
*
* NOTE: TBD: Flags parameter is obsolete, to be removed
*
******************************************************************************/
acpi_status acpi_set_register(u32 register_id, u32 value, u32 flags)
{
u32 register_value = 0;
struct acpi_bit_register_info *bit_reg_info;
acpi_status status;
acpi_cpu_flags lock_flags;
ACPI_FUNCTION_TRACE_U32(acpi_set_register, register_id);
/* Get the info structure corresponding to the requested ACPI Register */
bit_reg_info = acpi_hw_get_bit_register_info(register_id);
if (!bit_reg_info) {
ACPI_ERROR((AE_INFO, "Bad ACPI HW RegisterId: %X",
register_id));
return_ACPI_STATUS(AE_BAD_PARAMETER);
}
lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
/* Always do a register read first so we can insert the new bits */
status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
bit_reg_info->parent_register,
®ister_value);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/*
* Decode the Register ID
* Register ID = [Register block ID] | [bit ID]
*
* Check bit ID to fine locate Register offset.
* Check Mask to determine Register offset, and then read-write.
*/
switch (bit_reg_info->parent_register) {
case ACPI_REGISTER_PM1_STATUS:
/*
* Status Registers are different from the rest. Clear by
* writing 1, and writing 0 has no effect. So, the only relevant
* information is the single bit we're interested in, all others should
* be written as 0 so they will be left unchanged.
*/
value = ACPI_REGISTER_PREPARE_BITS(value,
bit_reg_info->bit_position,
bit_reg_info->
access_bit_mask);
if (value) {
status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_STATUS,
(u16) value);
register_value = 0;
}
break;
case ACPI_REGISTER_PM1_ENABLE:
ACPI_REGISTER_INSERT_VALUE(register_value,
bit_reg_info->bit_position,
bit_reg_info->access_bit_mask,
value);
status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_ENABLE,
(u16) register_value);
break;
case ACPI_REGISTER_PM1_CONTROL:
/*
* Write the PM1 Control register.
* Note that at this level, the fact that there are actually TWO
* registers (A and B - and B may not exist) is abstracted.
*/
ACPI_DEBUG_PRINT((ACPI_DB_IO, "PM1 control: Read %X\n",
register_value));
ACPI_REGISTER_INSERT_VALUE(register_value,
bit_reg_info->bit_position,
bit_reg_info->access_bit_mask,
value);
status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_CONTROL,
(u16) register_value);
break;
case ACPI_REGISTER_PM2_CONTROL:
status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM2_CONTROL,
®ister_value);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"PM2 control: Read %X from %8.8X%8.8X\n",
register_value,
ACPI_FORMAT_UINT64(acpi_gbl_FADT.
xpm2_control_block.
address)));
ACPI_REGISTER_INSERT_VALUE(register_value,
bit_reg_info->bit_position,
bit_reg_info->access_bit_mask,
value);
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"About to write %4.4X to %8.8X%8.8X\n",
register_value,
ACPI_FORMAT_UINT64(acpi_gbl_FADT.
xpm2_control_block.
address)));
status = acpi_hw_register_write(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM2_CONTROL,
(u8) (register_value));
break;
default:
break;
}
unlock_and_exit:
acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
/* Normalize the value that was read */
ACPI_DEBUG_EXEC(register_value =
((register_value & bit_reg_info->access_bit_mask) >>
bit_reg_info->bit_position));
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"Set bits: %8.8X actual %8.8X register %X\n", value,
register_value, bit_reg_info->parent_register));
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL(acpi_set_register)
/******************************************************************************
*
* FUNCTION: acpi_hw_register_read
*
* PARAMETERS: use_lock - Lock hardware? True/False
* register_id - ACPI Register ID
* return_value - Where the register value is returned
*
* RETURN: Status and the value read.
*
* DESCRIPTION: Read from the specified ACPI register
*
******************************************************************************/
acpi_status
acpi_hw_register_read(u8 use_lock, u32 register_id, u32 * return_value)
{
u32 value1 = 0;
u32 value2 = 0;
acpi_status status;
acpi_cpu_flags lock_flags = 0;
ACPI_FUNCTION_TRACE(hw_register_read);
if (ACPI_MTX_LOCK == use_lock) {
lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
}
switch (register_id) {
case ACPI_REGISTER_PM1_STATUS: /* 16-bit access */
status =
acpi_hw_low_level_read(16, &value1,
&acpi_gbl_FADT.xpm1a_event_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* PM1B is optional */
status =
acpi_hw_low_level_read(16, &value2,
&acpi_gbl_FADT.xpm1b_event_block);
value1 |= value2;
break;
case ACPI_REGISTER_PM1_ENABLE: /* 16-bit access */
status =
acpi_hw_low_level_read(16, &value1, &acpi_gbl_xpm1a_enable);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* PM1B is optional */
status =
acpi_hw_low_level_read(16, &value2, &acpi_gbl_xpm1b_enable);
value1 |= value2;
break;
case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */
status =
acpi_hw_low_level_read(16, &value1,
&acpi_gbl_FADT.xpm1a_control_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
status =
acpi_hw_low_level_read(16, &value2,
&acpi_gbl_FADT.xpm1b_control_block);
value1 |= value2;
break;
case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
status =
acpi_hw_low_level_read(8, &value1,
&acpi_gbl_FADT.xpm2_control_block);
break;
case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
status =
acpi_hw_low_level_read(32, &value1,
&acpi_gbl_FADT.xpm_timer_block);
break;
case ACPI_REGISTER_SMI_COMMAND_BLOCK: /* 8-bit access */
status =
acpi_os_read_port(acpi_gbl_FADT.smi_command, &value1, 8);
break;
default:
ACPI_ERROR((AE_INFO, "Unknown Register ID: %X", register_id));
status = AE_BAD_PARAMETER;
break;
}
unlock_and_exit:
if (ACPI_MTX_LOCK == use_lock) {
acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
}
if (ACPI_SUCCESS(status)) {
*return_value = value1;
}
return_ACPI_STATUS(status);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_register_write
*
* PARAMETERS: use_lock - Lock hardware? True/False
* register_id - ACPI Register ID
* Value - The value to write
*
* RETURN: Status
*
* DESCRIPTION: Write to the specified ACPI register
*
* NOTE: In accordance with the ACPI specification, this function automatically
* preserves the value of the following bits, meaning that these bits cannot be
* changed via this interface:
*
* PM1_CONTROL[0] = SCI_EN
* PM1_CONTROL[9]
* PM1_STATUS[11]
*
* ACPI References:
* 1) Hardware Ignored Bits: When software writes to a register with ignored
* bit fields, it preserves the ignored bit fields
* 2) SCI_EN: OSPM always preserves this bit position
*
******************************************************************************/
acpi_status acpi_hw_register_write(u8 use_lock, u32 register_id, u32 value)
{
acpi_status status;
acpi_cpu_flags lock_flags = 0;
u32 read_value;
ACPI_FUNCTION_TRACE(hw_register_write);
if (ACPI_MTX_LOCK == use_lock) {
lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);
}
switch (register_id) {
case ACPI_REGISTER_PM1_STATUS: /* 16-bit access */
/* Perform a read first to preserve certain bits (per ACPI spec) */
status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_STATUS,
&read_value);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* Insert the bits to be preserved */
ACPI_INSERT_BITS(value, ACPI_PM1_STATUS_PRESERVED_BITS,
read_value);
/* Now we can write the data */
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1a_event_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* PM1B is optional */
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1b_event_block);
break;
case ACPI_REGISTER_PM1_ENABLE: /* 16-bit access */
status =
acpi_hw_low_level_write(16, value, &acpi_gbl_xpm1a_enable);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* PM1B is optional */
status =
acpi_hw_low_level_write(16, value, &acpi_gbl_xpm1b_enable);
break;
case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */
/*
* Perform a read first to preserve certain bits (per ACPI spec)
*/
status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK,
ACPI_REGISTER_PM1_CONTROL,
&read_value);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
/* Insert the bits to be preserved */
ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS,
read_value);
/* Now we can write the data */
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1a_control_block);
if (ACPI_FAILURE(status)) {
goto unlock_and_exit;
}
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1b_control_block);
break;
case ACPI_REGISTER_PM1A_CONTROL: /* 16-bit access */
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1a_control_block);
break;
case ACPI_REGISTER_PM1B_CONTROL: /* 16-bit access */
status =
acpi_hw_low_level_write(16, value,
&acpi_gbl_FADT.xpm1b_control_block);
break;
case ACPI_REGISTER_PM2_CONTROL: /* 8-bit access */
status =
acpi_hw_low_level_write(8, value,
&acpi_gbl_FADT.xpm2_control_block);
break;
case ACPI_REGISTER_PM_TIMER: /* 32-bit access */
status =
acpi_hw_low_level_write(32, 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_os_write_port(acpi_gbl_FADT.smi_command, value, 8);
break;
default:
status = AE_BAD_PARAMETER;
break;
}
unlock_and_exit:
if (ACPI_MTX_LOCK == use_lock) {
acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
}
return_ACPI_STATUS(status);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_low_level_read
*
* PARAMETERS: Width - 8, 16, or 32
* Value - Where the value is returned
* Reg - GAS register structure
*
* RETURN: Status
*
* DESCRIPTION: Read from either memory or IO space.
*
******************************************************************************/
acpi_status
acpi_hw_low_level_read(u32 width, u32 * value, struct acpi_generic_address *reg)
{
u64 address;
acpi_status status;
ACPI_FUNCTION_NAME(hw_low_level_read);
/*
* Must have a valid pointer to a GAS structure, and
* a non-zero address within. However, don't return an error
* because the PM1A/B code must not fail if B isn't present.
*/
if (!reg) {
return (AE_OK);
}
/* Get a local copy of the address. Handles possible alignment issues */
ACPI_MOVE_64_TO_64(&address, ®->address);
if (!address) {
return (AE_OK);
}
*value = 0;
/*
* Two address spaces supported: Memory or IO.
* PCI_Config is not supported here because the GAS struct is insufficient
*/
switch (reg->space_id) {
case ACPI_ADR_SPACE_SYSTEM_MEMORY:
status = acpi_os_read_memory((acpi_physical_address) address,
value, width);
break;
case ACPI_ADR_SPACE_SYSTEM_IO:
status = acpi_os_read_port((acpi_io_address) address,
value, width);
break;
default:
ACPI_ERROR((AE_INFO,
"Unsupported address space: %X", reg->space_id));
return (AE_BAD_PARAMETER);
}
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"Read: %8.8X width %2d from %8.8X%8.8X (%s)\n",
*value, width,
ACPI_FORMAT_UINT64(address),
acpi_ut_get_region_name(reg->space_id)));
return (status);
}
/******************************************************************************
*
* FUNCTION: acpi_hw_low_level_write
*
* PARAMETERS: Width - 8, 16, or 32
* Value - To be written
* Reg - GAS register structure
*
* RETURN: Status
*
* DESCRIPTION: Write to either memory or IO space.
*
******************************************************************************/
acpi_status
acpi_hw_low_level_write(u32 width, u32 value, struct acpi_generic_address * reg)
{
u64 address;
acpi_status status;
ACPI_FUNCTION_NAME(hw_low_level_write);
/*
* Must have a valid pointer to a GAS structure, and
* a non-zero address within. However, don't return an error
* because the PM1A/B code must not fail if B isn't present.
*/
if (!reg) {
return (AE_OK);
}
/* Get a local copy of the address. Handles possible alignment issues */
ACPI_MOVE_64_TO_64(&address, ®->address);
if (!address) {
return (AE_OK);
}
/*
* Two address spaces supported: Memory or IO.
* PCI_Config is not supported here because the GAS struct is insufficient
*/
switch (reg->space_id) {
case ACPI_ADR_SPACE_SYSTEM_MEMORY:
status = acpi_os_write_memory((acpi_physical_address) address,
value, width);
break;
case ACPI_ADR_SPACE_SYSTEM_IO:
status = acpi_os_write_port((acpi_io_address) address,
value, width);
break;
default:
ACPI_ERROR((AE_INFO,
"Unsupported address space: %X", reg->space_id));
return (AE_BAD_PARAMETER);
}
ACPI_DEBUG_PRINT((ACPI_DB_IO,
"Wrote: %8.8X width %2d to %8.8X%8.8X (%s)\n",
value, width,
ACPI_FORMAT_UINT64(address),
acpi_ut_get_region_name(reg->space_id)));
return (status);
}
