hwxface.c

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/******************************************************************************
 *
 * Module Name: hwxface - Public ACPICA hardware interfaces
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2012, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include <linux/export.h>
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_HARDWARE
ACPI_MODULE_NAME("hwxface")

/******************************************************************************
 *
 * FUNCTION:    acpi_reset
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Set reset register in memory or IO space. Note: Does not
 *              support reset register in PCI config space, this must be
 *              handled separately.
 *
 ******************************************************************************/
acpi_status acpi_reset(void)
{
    struct acpi_generic_address *reset_reg;
    acpi_status status;

    ACPI_FUNCTION_TRACE(acpi_reset);

    reset_reg = &acpi_gbl_FADT.reset_register;

    /* Check if the reset register is supported */

    if (!(acpi_gbl_FADT.flags & ACPI_FADT_RESET_REGISTER) ||
        !reset_reg->address) {
        return_ACPI_STATUS(AE_NOT_EXIST);
    }

    if (reset_reg->space_id == ACPI_ADR_SPACE_SYSTEM_IO) {
        /*
         * For I/O space, write directly to the OSL. This
         * bypasses the port validation mechanism, which may
         * block a valid write to the reset register. Spec
         * section 4.7.3.6 requires register width to be 8.
         */
        status =
            acpi_os_write_port((acpi_io_address) reset_reg->address,
                       acpi_gbl_FADT.reset_value, 8);
    } else {
        /* Write the reset value to the reset register */

        status = acpi_hw_write(acpi_gbl_FADT.reset_value, reset_reg);
    }

    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_reset)

/******************************************************************************
 *
 * FUNCTION:    acpi_read
 *
 * PARAMETERS:  value               - Where the value is returned
 *              reg                 - GAS register structure
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Read from either memory or IO space.
 *
 * LIMITATIONS: <These limitations also apply to acpi_write>
 *      bit_width must be exactly 8, 16, 32, or 64.
 *      space_ID must be system_memory or system_IO.
 *      bit_offset and access_width are currently ignored, as there has
 *          not been a need to implement these.
 *
 ******************************************************************************/
acpi_status acpi_read(u64 *return_value, struct acpi_generic_address *reg)
{
    u32 value;
    u32 width;
    u64 address;
    acpi_status status;

    ACPI_FUNCTION_NAME(acpi_read);

    if (!return_value) {
        return (AE_BAD_PARAMETER);
    }

    /* Validate contents of the GAS register. Allow 64-bit transfers */

    status = acpi_hw_validate_register(reg, 64, &address);
    if (ACPI_FAILURE(status)) {
        return (status);
    }

    /* Initialize entire 64-bit return value to zero */

    *return_value = 0;
    value = 0;

    /*
     * Two address spaces supported: Memory or IO. PCI_Config is
     * not supported here because the GAS structure is insufficient
     */
    if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
        status = acpi_os_read_memory((acpi_physical_address)
                         address, return_value,
                         reg->bit_width);
        if (ACPI_FAILURE(status)) {
            return (status);
        }
    } else {        /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */

        width = reg->bit_width;
        if (width == 64) {
            width = 32; /* Break into two 32-bit transfers */
        }

        status = acpi_hw_read_port((acpi_io_address)
                       address, &value, width);
        if (ACPI_FAILURE(status)) {
            return (status);
        }
        *return_value = value;

        if (reg->bit_width == 64) {

            /* Read the top 32 bits */

            status = acpi_hw_read_port((acpi_io_address)
                           (address + 4), &value, 32);
            if (ACPI_FAILURE(status)) {
                return (status);
            }
            *return_value |= ((u64)value << 32);
        }
    }

    ACPI_DEBUG_PRINT((ACPI_DB_IO,
              "Read:  %8.8X%8.8X width %2d from %8.8X%8.8X (%s)\n",
              ACPI_FORMAT_UINT64(*return_value), reg->bit_width,
              ACPI_FORMAT_UINT64(address),
              acpi_ut_get_region_name(reg->space_id)));

    return (status);
}

ACPI_EXPORT_SYMBOL(acpi_read)

/******************************************************************************
 *
 * FUNCTION:    acpi_write
 *
 * PARAMETERS:  value               - Value to be written
 *              reg                 - GAS register structure
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Write to either memory or IO space.
 *
 ******************************************************************************/
acpi_status acpi_write(u64 value, struct acpi_generic_address *reg)
{
    u32 width;
    u64 address;
    acpi_status status;

    ACPI_FUNCTION_NAME(acpi_write);

    /* Validate contents of the GAS register. Allow 64-bit transfers */

    status = acpi_hw_validate_register(reg, 64, &address);
    if (ACPI_FAILURE(status)) {
        return (status);
    }

    /*
     * Two address spaces supported: Memory or IO. PCI_Config is
     * not supported here because the GAS structure is insufficient
     */
    if (reg->space_id == ACPI_ADR_SPACE_SYSTEM_MEMORY) {
        status = acpi_os_write_memory((acpi_physical_address)
                          address, value, reg->bit_width);
        if (ACPI_FAILURE(status)) {
            return (status);
        }
    } else {        /* ACPI_ADR_SPACE_SYSTEM_IO, validated earlier */

        width = reg->bit_width;
        if (width == 64) {
            width = 32; /* Break into two 32-bit transfers */
        }

        status = acpi_hw_write_port((acpi_io_address)
                        address, ACPI_LODWORD(value),
                        width);
        if (ACPI_FAILURE(status)) {
            return (status);
        }

        if (reg->bit_width == 64) {
            status = acpi_hw_write_port((acpi_io_address)
                            (address + 4),
                            ACPI_HIDWORD(value), 32);
            if (ACPI_FAILURE(status)) {
                return (status);
            }
        }
    }

    ACPI_DEBUG_PRINT((ACPI_DB_IO,
              "Wrote: %8.8X%8.8X width %2d   to %8.8X%8.8X (%s)\n",
              ACPI_FORMAT_UINT64(value), reg->bit_width,
              ACPI_FORMAT_UINT64(address),
              acpi_ut_get_region_name(reg->space_id)));

    return (status);
}

ACPI_EXPORT_SYMBOL(acpi_write)

#if (!ACPI_REDUCED_HARDWARE)
/*******************************************************************************
 *
 * FUNCTION:    acpi_read_bit_register
 *
 * PARAMETERS:  register_id     - ID of ACPI Bit Register to access
 *              return_value    - Value that was read from the register,
 *                                normalized to bit position zero.
 *
 * RETURN:      Status and the value read from the specified Register. Value
 *              returned is normalized to bit0 (is shifted all the way right)
 *
 * DESCRIPTION: ACPI bit_register read function. Does not acquire the HW lock.
 *
 * SUPPORTS:    Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
 *              PM2 Control.
 *
 * Note: The hardware lock is not required when reading the ACPI bit registers
 *       since almost all of them are single bit and it does not matter that
 *       the parent hardware register can be split across two physical
 *       registers. The only multi-bit field is SLP_TYP in the PM1 control
 *       register, but this field does not cross an 8-bit boundary (nor does
 *       it make much sense to actually read this field.)
 *
 ******************************************************************************/
acpi_status acpi_read_bit_register(u32 register_id, u32 *return_value)
{
    struct acpi_bit_register_info *bit_reg_info;
    u32 register_value;
    u32 value;
    acpi_status status;

    ACPI_FUNCTION_TRACE_U32(acpi_read_bit_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) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    /* Read the entire parent register */

    status = acpi_hw_register_read(bit_reg_info->parent_register,
                       &register_value);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    /* Normalize the value that was read, mask off other bits */

    value = ((register_value & bit_reg_info->access_bit_mask)
         >> bit_reg_info->bit_position);

    ACPI_DEBUG_PRINT((ACPI_DB_IO,
              "BitReg %X, ParentReg %X, Actual %8.8X, ReturnValue %8.8X\n",
              register_id, bit_reg_info->parent_register,
              register_value, value));

    *return_value = value;
    return_ACPI_STATUS(AE_OK);
}

ACPI_EXPORT_SYMBOL(acpi_read_bit_register)

/*******************************************************************************
 *
 * FUNCTION:    acpi_write_bit_register
 *
 * PARAMETERS:  register_id     - ID of ACPI Bit Register to access
 *              Value           - Value to write to the register, in bit
 *                                position zero. The bit is automatically
 *                                shifted to the correct position.
 *
 * RETURN:      Status
 *
 * DESCRIPTION: ACPI Bit Register write function. Acquires the hardware lock
 *              since most operations require a read/modify/write sequence.
 *
 * SUPPORTS:    Bit fields in PM1 Status, PM1 Enable, PM1 Control, and
 *              PM2 Control.
 *
 * Note that at this level, the fact that there may be actually two
 * hardware registers (A and B - and B may not exist) is abstracted.
 *
 ******************************************************************************/
acpi_status acpi_write_bit_register(u32 register_id, u32 value)
{
    struct acpi_bit_register_info *bit_reg_info;
    acpi_cpu_flags lock_flags;
    u32 register_value;
    acpi_status status = AE_OK;

    ACPI_FUNCTION_TRACE_U32(acpi_write_bit_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) {
        return_ACPI_STATUS(AE_BAD_PARAMETER);
    }

    lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock);

    /*
     * At this point, we know that the parent register is one of the
     * following: PM1 Status, PM1 Enable, PM1 Control, or PM2 Control
     */
    if (bit_reg_info->parent_register != ACPI_REGISTER_PM1_STATUS) {
        /*
         * 1) Case for PM1 Enable, PM1 Control, and PM2 Control
         *
         * Perform a register read to preserve the bits that we are not
         * interested in
         */
        status = acpi_hw_register_read(bit_reg_info->parent_register,
                           &register_value);
        if (ACPI_FAILURE(status)) {
            goto unlock_and_exit;
        }

        /*
         * Insert the input bit into the value that was just read
         * and write the register
         */
        ACPI_REGISTER_INSERT_VALUE(register_value,
                       bit_reg_info->bit_position,
                       bit_reg_info->access_bit_mask,
                       value);

        status = acpi_hw_register_write(bit_reg_info->parent_register,
                        register_value);
    } else {
        /*
         * 2) Case for PM1 Status
         *
         * The Status register is different from the rest. Clear an event
         * by writing 1, 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.
         */
        register_value = ACPI_REGISTER_PREPARE_BITS(value,
                                bit_reg_info->
                                bit_position,
                                bit_reg_info->
                                access_bit_mask);

        /* No need to write the register if value is all zeros */

        if (register_value) {
            status =
                acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS,
                           register_value);
        }
    }

    ACPI_DEBUG_PRINT((ACPI_DB_IO,
              "BitReg %X, ParentReg %X, Value %8.8X, Actual %8.8X\n",
              register_id, bit_reg_info->parent_register, value,
              register_value));

unlock_and_exit:

    acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags);
    return_ACPI_STATUS(status);
}

ACPI_EXPORT_SYMBOL(acpi_write_bit_register)
#endif              /* !ACPI_REDUCED_HARDWARE */
/*******************************************************************************
 *
 * 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 (info->return_object->common.type != 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 (((info->return_object->package.elements[0])->common.type
          != ACPI_TYPE_INTEGER) ||
         ((info->return_object->package.elements[1])->common.type
          != 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)