// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
 *
 * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
 *                   original/legacy sleep/PM registers.
 *
 * Copyright (C) 2000 - 2025, Intel Corp.
 *
 *****************************************************************************/

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

#define _COMPONENT          ACPI_HARDWARE
ACPI_MODULE_NAME("hwsleep")

#if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_legacy_sleep
 *
 * PARAMETERS:  sleep_state         - Which sleep state to enter
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
 *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 *
 ******************************************************************************/
acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
{
        struct acpi_bit_register_info *sleep_type_reg_info;
        struct acpi_bit_register_info *sleep_enable_reg_info;
        u32 pm1a_control;
        u32 pm1b_control;
        u32 in_value;
        acpi_status status;

        ACPI_FUNCTION_TRACE(hw_legacy_sleep);

        sleep_type_reg_info =
            acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
        sleep_enable_reg_info =
            acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);

        /* Clear wake status */

        status = acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
                                         ACPI_CLEAR_STATUS);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Disable all GPEs */
        status = acpi_hw_disable_all_gpes();
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }
        status = acpi_hw_clear_acpi_status();
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }
        acpi_gbl_system_awake_and_running = FALSE;

         /* Enable all wakeup GPEs */
        status = acpi_hw_enable_all_wakeup_gpes();
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Get current value of PM1A control */

        status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
                                       &pm1a_control);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }
        ACPI_DEBUG_PRINT((ACPI_DB_INIT,
                          "Entering sleep state [S%u]\n", sleep_state));

        /* Clear the SLP_EN and SLP_TYP fields */

        pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
                          sleep_enable_reg_info->access_bit_mask);
        pm1b_control = pm1a_control;

        /* Insert the SLP_TYP bits */

        pm1a_control |=
            (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
        pm1b_control |=
            (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);

        /*
         * We split the writes of SLP_TYP and SLP_EN to workaround
         * poorly implemented hardware.
         */

        /* Write #1: write the SLP_TYP data to the PM1 Control registers */

        status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Insert the sleep enable (SLP_EN) bit */

        pm1a_control |= sleep_enable_reg_info->access_bit_mask;
        pm1b_control |= sleep_enable_reg_info->access_bit_mask;

        /* Flush caches, as per ACPI specification */

        if (sleep_state < ACPI_STATE_S4) {
                ACPI_FLUSH_CPU_CACHE();
        }

        status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
        if (status == AE_CTRL_TERMINATE) {
                return_ACPI_STATUS(AE_OK);
        }
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /* Write #2: Write both SLP_TYP + SLP_EN */

        status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        if (sleep_state > ACPI_STATE_S3) {
                /*
                 * We wanted to sleep > S3, but it didn't happen (by virtue of the
                 * fact that we are still executing!)
                 *
                 * Wait ten seconds, then try again. This is to get S4/S5 to work on
                 * all machines.
                 *
                 * We wait so long to allow chipsets that poll this reg very slowly
                 * to still read the right value. Ideally, this block would go
                 * away entirely.
                 */
                acpi_os_stall(10 * ACPI_USEC_PER_SEC);

                status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
                                                sleep_enable_reg_info->
                                                access_bit_mask);
                if (ACPI_FAILURE(status)) {
                        return_ACPI_STATUS(status);
                }
        }

        /* Wait for transition back to Working State */

        do {
                status =
                    acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
                if (ACPI_FAILURE(status)) {
                        return_ACPI_STATUS(status);
                }

        } while (!in_value);

        return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_legacy_wake_prep
 *
 * PARAMETERS:  sleep_state         - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 *              sleep.
 *              Called with interrupts ENABLED.
 *
 ******************************************************************************/

acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
{
        acpi_status status = AE_OK;
        struct acpi_bit_register_info *sleep_type_reg_info;
        struct acpi_bit_register_info *sleep_enable_reg_info;
        u32 pm1a_control;
        u32 pm1b_control;

        ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);

        /*
         * Set SLP_TYPE and SLP_EN to state S0.
         * This is unclear from the ACPI Spec, but it is required
         * by some machines.
         */
        if (acpi_gbl_sleep_type_a_s0 != ACPI_SLEEP_TYPE_INVALID) {
                sleep_type_reg_info =
                    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
                sleep_enable_reg_info =
                    acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);

                /* Get current value of PM1A control */

                status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
                                               &pm1a_control);
                if (ACPI_SUCCESS(status)) {

                        /* Clear the SLP_EN and SLP_TYP fields */

                        pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
                                          sleep_enable_reg_info->
                                          access_bit_mask);
                        pm1b_control = pm1a_control;

                        /* Insert the SLP_TYP bits */

                        pm1a_control |= (acpi_gbl_sleep_type_a_s0 <<
                                         sleep_type_reg_info->bit_position);
                        pm1b_control |= (acpi_gbl_sleep_type_b_s0 <<
                                         sleep_type_reg_info->bit_position);

                        /* Write the control registers and ignore any errors */

                        (void)acpi_hw_write_pm1_control(pm1a_control,
                                                        pm1b_control);
                }
        }

        return_ACPI_STATUS(status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_legacy_wake
 *
 * PARAMETERS:  sleep_state         - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 *              Called with interrupts ENABLED.
 *
 ******************************************************************************/

acpi_status acpi_hw_legacy_wake(u8 sleep_state)
{
        acpi_status status;

        ACPI_FUNCTION_TRACE(hw_legacy_wake);

        /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */

        acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
        acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);

        /*
         * GPEs must be enabled before _WAK is called as GPEs
         * might get fired there
         *
         * Restore the GPEs:
         * 1) Disable all GPEs
         * 2) Enable all runtime GPEs
         */
        status = acpi_hw_disable_all_gpes();
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        status = acpi_hw_enable_all_runtime_gpes();
        if (ACPI_FAILURE(status)) {
                return_ACPI_STATUS(status);
        }

        /*
         * Now we can execute _WAK, etc. Some machines require that the GPEs
         * are enabled before the wake methods are executed.
         */
        acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);

        /*
         * Some BIOS code assumes that WAK_STS will be cleared on resume
         * and use it to determine whether the system is rebooting or
         * resuming. Clear WAK_STS for compatibility.
         */
        (void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
                                      ACPI_CLEAR_STATUS);
        acpi_gbl_system_awake_and_running = TRUE;

        /* Enable power button */

        (void)
            acpi_write_bit_register(acpi_gbl_fixed_event_info
                                    [ACPI_EVENT_POWER_BUTTON].
                                    enable_register_id, ACPI_ENABLE_EVENT);

        (void)
            acpi_write_bit_register(acpi_gbl_fixed_event_info
                                    [ACPI_EVENT_POWER_BUTTON].
                                    status_register_id, ACPI_CLEAR_STATUS);

        /* Enable sleep button */

        (void)
            acpi_write_bit_register(acpi_gbl_fixed_event_info
                                    [ACPI_EVENT_SLEEP_BUTTON].
                                    enable_register_id, ACPI_ENABLE_EVENT);

        (void)
            acpi_write_bit_register(acpi_gbl_fixed_event_info
                                    [ACPI_EVENT_SLEEP_BUTTON].
                                    status_register_id, ACPI_CLEAR_STATUS);

        acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
        return_ACPI_STATUS(status);
}

#endif                          /* !ACPI_REDUCED_HARDWARE */