root/drivers/acpi/acpica/evsci.c
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
 *
 * Module Name: evsci - System Control Interrupt configuration and
 *                      legacy to ACPI mode state transition functions
 *
 ******************************************************************************/

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

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evsci")
#if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
/* Local prototypes */
static u32 ACPI_SYSTEM_XFACE acpi_ev_sci_xrupt_handler(void *context);

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_sci_dispatch
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status code indicates whether interrupt was handled.
 *
 * DESCRIPTION: Dispatch the SCI to all host-installed SCI handlers.
 *
 ******************************************************************************/

u32 acpi_ev_sci_dispatch(void)
{
        struct acpi_sci_handler_info *sci_handler;
        acpi_cpu_flags flags;
        u32 int_status = ACPI_INTERRUPT_NOT_HANDLED;

        ACPI_FUNCTION_NAME(ev_sci_dispatch);

        /* Are there any host-installed SCI handlers? */

        if (!acpi_gbl_sci_handler_list) {
                return (int_status);
        }

        flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);

        /* Invoke all host-installed SCI handlers */

        sci_handler = acpi_gbl_sci_handler_list;
        while (sci_handler) {

                /* Invoke the installed handler (at interrupt level) */

                int_status |= sci_handler->address(sci_handler->context);

                sci_handler = sci_handler->next;
        }

        acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
        return (int_status);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_sci_xrupt_handler
 *
 * PARAMETERS:  context   - Calling Context
 *
 * RETURN:      Status code indicates whether interrupt was handled.
 *
 * DESCRIPTION: Interrupt handler that will figure out what function or
 *              control method to call to deal with a SCI.
 *
 ******************************************************************************/

static u32 ACPI_SYSTEM_XFACE acpi_ev_sci_xrupt_handler(void *context)
{
        struct acpi_gpe_xrupt_info *gpe_xrupt_list = context;
        u32 interrupt_handled = ACPI_INTERRUPT_NOT_HANDLED;

        ACPI_FUNCTION_TRACE(ev_sci_xrupt_handler);

        /*
         * We are guaranteed by the ACPICA initialization/shutdown code that
         * if this interrupt handler is installed, ACPI is enabled.
         */

        /*
         * Fixed Events:
         * Check for and dispatch any Fixed Events that have occurred
         */
        interrupt_handled |= acpi_ev_fixed_event_detect();

        /*
         * General Purpose Events:
         * Check for and dispatch any GPEs that have occurred
         */
        interrupt_handled |= acpi_ev_gpe_detect(gpe_xrupt_list);

        /* Invoke all host-installed SCI handlers */

        interrupt_handled |= acpi_ev_sci_dispatch();

        acpi_sci_count++;
        return_UINT32(interrupt_handled);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_xrupt_handler
 *
 * PARAMETERS:  context   - Calling Context
 *
 * RETURN:      Status code indicates whether interrupt was handled.
 *
 * DESCRIPTION: Handler for GPE Block Device interrupts
 *
 ******************************************************************************/

u32 ACPI_SYSTEM_XFACE acpi_ev_gpe_xrupt_handler(void *context)
{
        struct acpi_gpe_xrupt_info *gpe_xrupt_list = context;
        u32 interrupt_handled = ACPI_INTERRUPT_NOT_HANDLED;

        ACPI_FUNCTION_TRACE(ev_gpe_xrupt_handler);

        /*
         * We are guaranteed by the ACPICA initialization/shutdown code that
         * if this interrupt handler is installed, ACPI is enabled.
         */

        /* GPEs: Check for and dispatch any GPEs that have occurred */

        interrupt_handled |= acpi_ev_gpe_detect(gpe_xrupt_list);
        return_UINT32(interrupt_handled);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_ev_install_sci_handler
 *
 * PARAMETERS:  none
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Installs SCI handler.
 *
 ******************************************************************************/

u32 acpi_ev_install_sci_handler(void)
{
        u32 status = AE_OK;

        ACPI_FUNCTION_TRACE(ev_install_sci_handler);

        status =
            acpi_os_install_interrupt_handler((u32) acpi_gbl_FADT.sci_interrupt,
                                              acpi_ev_sci_xrupt_handler,
                                              acpi_gbl_gpe_xrupt_list_head);
        return_ACPI_STATUS(status);
}

/******************************************************************************
 *
 * FUNCTION:    acpi_ev_remove_all_sci_handlers
 *
 * PARAMETERS:  none
 *
 * RETURN:      AE_OK if handler uninstalled, AE_ERROR if handler was not
 *              installed to begin with
 *
 * DESCRIPTION: Remove the SCI interrupt handler. No further SCIs will be
 *              taken. Remove all host-installed SCI handlers.
 *
 * Note:  It doesn't seem important to disable all events or set the event
 *        enable registers to their original values. The OS should disable
 *        the SCI interrupt level when the handler is removed, so no more
 *        events will come in.
 *
 ******************************************************************************/

acpi_status acpi_ev_remove_all_sci_handlers(void)
{
        struct acpi_sci_handler_info *sci_handler;
        acpi_cpu_flags flags;
        acpi_status status;

        ACPI_FUNCTION_TRACE(ev_remove_all_sci_handlers);

        /* Just let the OS remove the handler and disable the level */

        status =
            acpi_os_remove_interrupt_handler((u32) acpi_gbl_FADT.sci_interrupt,
                                             acpi_ev_sci_xrupt_handler);

        if (!acpi_gbl_sci_handler_list) {
                return (status);
        }

        flags = acpi_os_acquire_lock(acpi_gbl_gpe_lock);

        /* Free all host-installed SCI handlers */

        while (acpi_gbl_sci_handler_list) {
                sci_handler = acpi_gbl_sci_handler_list;
                acpi_gbl_sci_handler_list = sci_handler->next;
                ACPI_FREE(sci_handler);
        }

        acpi_os_release_lock(acpi_gbl_gpe_lock, flags);
        return_ACPI_STATUS(status);
}

#endif                          /* !ACPI_REDUCED_HARDWARE */