--- /dev/null
+/*
+ * efi_selftest_events
+ *
+ * Copyright (c) 2017 Heinrich Schuchardt <xypron.glpk@gmx.de>
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
+ * This unit test uses timer events to check the handling of
+ * task priority levels.
+ */
+
+#include <efi_selftest.h>
+
+static struct efi_event *event_notify;
+static struct efi_event *event_wait;
+static unsigned int counter;
+static struct efi_boot_services *boottime;
+
+/*
+ * Notification function, increments a counter.
+ *
+ * @event notified event
+ * @context pointer to the counter
+ */
+static void EFIAPI notify(struct efi_event *event, void *context)
+{
+ if (!context)
+ return;
+ ++*(unsigned int *)context;
+}
+
+/*
+ * 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
+ */
+static int setup(const efi_handle_t handle,
+ const struct efi_system_table *systable)
+{
+ efi_status_t ret;
+
+ boottime = systable->boottime;
+
+ ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL,
+ TPL_CALLBACK, notify, (void *)&counter,
+ &event_notify);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("could not create event\n");
+ return 1;
+ }
+ ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_WAIT,
+ TPL_HIGH_LEVEL, notify, NULL, &event_wait);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("could not create event\n");
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Tear down unit test.
+ *
+ * Close the events created in setup.
+ */
+static int teardown(void)
+{
+ efi_status_t ret;
+
+ 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 1;
+ }
+ }
+ 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 1;
+ }
+ }
+ boottime->restore_tpl(TPL_APPLICATION);
+ return 0;
+}
+
+/*
+ * Execute unit test.
+ *
+ * Run a 10 ms periodic timer and check that it is called 10 times
+ * while waiting for 100 ms single shot timer.
+ *
+ * Raise the TPL level to the level of the 10 ms timer and observe
+ * that the notification function is not called again.
+ *
+ * Lower the TPL level and check that the queued notification
+ * function is called.
+ */
+static int execute(void)
+{
+ unsigned long index;
+ efi_status_t ret;
+ UINTN old_tpl;
+
+ /* Set 10 ms timer */
+ counter = 0;
+ ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not set timer\n");
+ return 1;
+ }
+ /* Set 100 ms timer */
+ ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not set timer\n");
+ return 1;
+ }
+ index = 5;
+ ret = boottime->wait_for_event(1, &event_wait, &index);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not wait for event\n");
+ return 1;
+ }
+ ret = boottime->check_event(event_wait);
+ if (ret != EFI_NOT_READY) {
+ efi_st_error("Signaled state was not cleared.\n");
+ efi_st_printf("ret = %u\n", (unsigned int)ret);
+ return 1;
+ }
+ if (index != 0) {
+ efi_st_error("WaitForEvent returned wrong index\n");
+ return 1;
+ }
+ efi_st_printf("Counter with TPL level TPL_APPLICATION: %u\n", counter);
+ if (counter < 8 || counter > 12) {
+ efi_st_error("Incorrect timing of events\n");
+ return 1;
+ }
+ ret = boottime->set_timer(event_notify, EFI_TIMER_STOP, 0);
+ if (index != 0) {
+ efi_st_error("Could not cancel timer\n");
+ return 1;
+ }
+ /* Raise TPL level */
+ old_tpl = boottime->raise_tpl(TPL_CALLBACK);
+ if (old_tpl != TPL_APPLICATION) {
+ efi_st_error("Initial TPL level was not TPL_APPLICATION");
+ return 1;
+ }
+ /* Set 10 ms timer */
+ counter = 0;
+ ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
+ if (index != 0) {
+ efi_st_error("Could not set timer\n");
+ return 1;
+ }
+ /* Set 100 ms timer */
+ ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not set timer\n");
+ return 1;
+ }
+ do {
+ ret = boottime->check_event(event_wait);
+ } while (ret == EFI_NOT_READY);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not check event\n");
+ return 1;
+ }
+ efi_st_printf("Counter with TPL level TPL_CALLBACK: %u\n", counter);
+ if (counter != 0) {
+ efi_st_error("Suppressed timer fired\n");
+ return 1;
+ }
+ /* Set 1 ms timer */
+ ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not set timer\n");
+ return 1;
+ }
+ /* Restore the old TPL level */
+ boottime->restore_tpl(TPL_APPLICATION);
+ ret = boottime->wait_for_event(1, &event_wait, &index);
+ if (ret != EFI_SUCCESS) {
+ efi_st_error("Could not wait for event\n");
+ return 1;
+ }
+ efi_st_printf("Counter with TPL level TPL_APPLICATION: %u\n", counter);
+ if (counter < 1) {
+ efi_st_error("Queued timer event did not fire\n");
+ return 1;
+ }
+ ret = boottime->set_timer(event_wait, EFI_TIMER_STOP, 0);
+ if (index != 0) {
+ efi_st_error("Could not cancel timer\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+EFI_UNIT_TEST(tpl) = {
+ .name = "task priority levels",
+ .phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
+ .setup = setup,
+ .execute = execute,
+ .teardown = teardown,
+};