// SPDX-License-Identifier: GPL-2.0+
/*
 * efi_selftest_watchdog
 *
 * Copyright (c) 2017 Heinrich Schuchardt <xypron.glpk@gmx.de>
 *
 * The 'watchdog timer' unit test checks that the watchdog timer
 * will not cause a system restart during the timeout period after
 * a timer reset.
 *
 * The 'watchdog reboot' unit test checks that the watchdog timer
 * actually reboots the system after a timeout. The test is only
 * executed on explicit request. Use the following commands:
 *
 *      setenv efi_selftest watchdog reboot
 *      bootefi selftest
 */

#include <efi_selftest.h>

/*
 * This is the communication structure for the notification function.
 */
struct notify_context {
        /* Status code returned when resetting watchdog */
        efi_status_t status;
        /* Number of invocations of the notification function */
        unsigned int timer_ticks;
};

static struct efi_event *event_notify;
static struct efi_event *event_wait;
static struct efi_boot_services *boottime;
static struct notify_context notification_context;
static bool watchdog_reset;

/*
 * Notification function, increments the notification count if parameter
 * context is provided.
 *
 * @event       notified event
 * @context     pointer to the timeout
 */
static void EFIAPI notify(struct efi_event *event, void *context)
{
        struct notify_context *notify_context = context;
        efi_status_t ret = EFI_SUCCESS;

        if (!notify_context)
                return;

        /* Reset watchdog timer to one second */
        ret = boottime->set_watchdog_timer(1, 0, 0, NULL);
        if (ret != EFI_SUCCESS)
                notify_context->status = ret;
        /* Count number of calls */
        notify_context->timer_ticks++;
}

/*
 * Setup unit test.
 *
 * Create two timer events.
 * One with EVT_NOTIFY_SIGNAL, the other with EVT_NOTIFY_WAIT.
 *
 * @handle:     handle of the loaded image
 * @systable:   system table
 * @return:     EFI_ST_SUCCESS for success
 */
static int setup(const efi_handle_t handle,
                 const struct efi_system_table *systable)
{
        efi_status_t ret;

        boottime = systable->boottime;

        notification_context.status = EFI_SUCCESS;
        notification_context.timer_ticks = 0;
        ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL,
                                     TPL_CALLBACK, notify,
                                     (void *)&notification_context,
                                     &event_notify);
        if (ret != EFI_SUCCESS) {
                efi_st_error("could not create event\n");
                return EFI_ST_FAILURE;
        }
        ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_WAIT,
                                     TPL_CALLBACK, notify, NULL, &event_wait);
        if (ret != EFI_SUCCESS) {
                efi_st_error("could not create event\n");
                return EFI_ST_FAILURE;
        }
        return EFI_ST_SUCCESS;
}

/*
 * Execute the test resetting the watchdog in a timely manner. No reboot occurs.
 *
 * @handle:     handle of the loaded image
 * @systable:   system table
 * @return:     EFI_ST_SUCCESS for success
 */
static int setup_timer(const efi_handle_t handle,
                       const struct efi_system_table *systable)
{
        watchdog_reset = true;
        return setup(handle, systable);
}

/*
 * Execute the test without resetting the watchdog. A system reboot occurs.
 *
 * @handle:     handle of the loaded image
 * @systable:   system table
 * @return:     EFI_ST_SUCCESS for success
 */
static int setup_reboot(const efi_handle_t handle,
                        const struct efi_system_table *systable)
{
        watchdog_reset = false;
        return setup(handle, systable);
}

/*
 * Tear down unit test.
 *
 * Close the events created in setup.
 *
 * @return:     EFI_ST_SUCCESS for success
 */
static int teardown(void)
{
        efi_status_t ret;

        /* Set the watchdog timer to the five minute default value */
        ret = boottime->set_watchdog_timer(300, 0, 0, NULL);
        if (ret != EFI_SUCCESS) {
                efi_st_error("Setting watchdog timer failed\n");
                return EFI_ST_FAILURE;
        }
        if (event_notify) {
                ret = boottime->close_event(event_notify);
                event_notify = NULL;
                if (ret != EFI_SUCCESS) {
                        efi_st_error("Could not close event\n");
                        return EFI_ST_FAILURE;
                }
        }
        if (event_wait) {
                ret = boottime->close_event(event_wait);
                event_wait = NULL;
                if (ret != EFI_SUCCESS) {
                        efi_st_error("Could not close event\n");
                        return EFI_ST_FAILURE;
                }
        }
        return EFI_ST_SUCCESS;
}

/*
 * Execute unit test.
 *
 * Run a 600 ms periodic timer that resets the watchdog to one second
 * on every timer tick.
 *
 * Run a 1350 ms single shot timer and check that the 600ms timer has
 * been called 2 times.
 *
 * @return:     EFI_ST_SUCCESS for success
 */
static int execute(void)
{
        size_t index;
        efi_status_t ret;

        /* Set the watchdog timeout to one second */
        ret = boottime->set_watchdog_timer(1, 0, 0, NULL);
        if (ret != EFI_SUCCESS) {
                efi_st_error("Setting watchdog timer failed\n");
                return EFI_ST_FAILURE;
        }
        if (watchdog_reset) {
                /* Set 600 ms timer */
                ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC,
                                          6000000);
                if (ret != EFI_SUCCESS) {
                        efi_st_error("Could not set timer\n");
                        return EFI_ST_FAILURE;
                }
        }
        /* Set 1350 ms timer */
        ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 13500000);
        if (ret != EFI_SUCCESS) {
                efi_st_error("Could not set timer\n");
                return EFI_ST_FAILURE;
        }

        ret = boottime->wait_for_event(1, &event_wait, &index);
        if (ret != EFI_SUCCESS) {
                efi_st_error("Could not wait for event\n");
                return EFI_ST_FAILURE;
        }
        if (notification_context.status != EFI_SUCCESS) {
                efi_st_error("Setting watchdog timer failed\n");
                return EFI_ST_FAILURE;
        }
        if (notification_context.timer_ticks != 2) {
                efi_st_error("The timer was called %u times, expected 2.\n",
                             notification_context.timer_ticks);
                return EFI_ST_FAILURE;
        }
        return EFI_ST_SUCCESS;
}

EFI_UNIT_TEST(watchdog1) = {
        .name = "watchdog timer",
        .phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
        .setup = setup_timer,
        .execute = execute,
        .teardown = teardown,
};

EFI_UNIT_TEST(watchdog2) = {
        .name = "watchdog reboot",
        .phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
        .setup = setup_reboot,
        .execute = execute,
        .teardown = teardown,
        .on_request = true,
};