1 /*
2  * efi_selftest_events
3  *
4  * Copyright (c) 2017 Heinrich Schuchardt <xypron.glpk@gmx.de>
5  *
6  * SPDX-License-Identifier:     GPL-2.0+
7  *
8  * This unit test uses timer events to check the handling of
9  * task priority levels.
10  */
11 
12 #include <efi_selftest.h>
13 
14 static struct efi_event *event_notify;
15 static struct efi_event *event_wait;
16 static unsigned int counter;
17 static struct efi_boot_services *boottime;
18 
19 /*
20  * Notification function, increments a counter.
21  *
22  * @event	notified event
23  * @context	pointer to the counter
24  */
25 static void EFIAPI notify(struct efi_event *event, void *context)
26 {
27 	if (!context)
28 		return;
29 	++*(unsigned int *)context;
30 }
31 
32 /*
33  * Setup unit test.
34  *
35  * Create two timer events.
36  * One with EVT_NOTIFY_SIGNAL, the other with EVT_NOTIFY_WAIT.
37  *
38  * @handle:	handle of the loaded image
39  * @systable:	system table
40  */
41 static int setup(const efi_handle_t handle,
42 		 const struct efi_system_table *systable)
43 {
44 	efi_status_t ret;
45 
46 	boottime = systable->boottime;
47 
48 	ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL,
49 				     TPL_CALLBACK, notify, (void *)&counter,
50 				     &event_notify);
51 	if (ret != EFI_SUCCESS) {
52 		efi_st_error("could not create event\n");
53 		return 1;
54 	}
55 	ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_WAIT,
56 				     TPL_HIGH_LEVEL, notify, NULL, &event_wait);
57 	if (ret != EFI_SUCCESS) {
58 		efi_st_error("could not create event\n");
59 		return 1;
60 	}
61 	return 0;
62 }
63 
64 /*
65  * Tear down unit test.
66  *
67  * Close the events created in setup.
68  */
69 static int teardown(void)
70 {
71 	efi_status_t ret;
72 
73 	if (event_notify) {
74 		ret = boottime->close_event(event_notify);
75 		event_notify = NULL;
76 		if (ret != EFI_SUCCESS) {
77 			efi_st_error("could not close event\n");
78 			return 1;
79 		}
80 	}
81 	if (event_wait) {
82 		ret = boottime->close_event(event_wait);
83 		event_wait = NULL;
84 		if (ret != EFI_SUCCESS) {
85 			efi_st_error("could not close event\n");
86 			return 1;
87 		}
88 	}
89 	boottime->restore_tpl(TPL_APPLICATION);
90 	return 0;
91 }
92 
93 /*
94  * Execute unit test.
95  *
96  * Run a 10 ms periodic timer and check that it is called 10 times
97  * while waiting for 100 ms single shot timer.
98  *
99  * Raise the TPL level to the level of the 10 ms timer and observe
100  * that the notification function is not called again.
101  *
102  * Lower the TPL level and check that the queued notification
103  * function is called.
104  */
105 static int execute(void)
106 {
107 	unsigned long index;
108 	efi_status_t ret;
109 	UINTN old_tpl;
110 
111 	/* Set 10 ms timer */
112 	counter = 0;
113 	ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
114 	if (ret != EFI_SUCCESS) {
115 		efi_st_error("Could not set timer\n");
116 		return 1;
117 	}
118 	/* Set 100 ms timer */
119 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
120 	if (ret != EFI_SUCCESS) {
121 		efi_st_error("Could not set timer\n");
122 		return 1;
123 	}
124 	index = 5;
125 	ret = boottime->wait_for_event(1, &event_wait, &index);
126 	if (ret != EFI_SUCCESS) {
127 		efi_st_error("Could not wait for event\n");
128 		return 1;
129 	}
130 	ret = boottime->check_event(event_wait);
131 	if (ret != EFI_NOT_READY) {
132 		efi_st_error("Signaled state was not cleared.\n");
133 		efi_st_printf("ret = %u\n", (unsigned int)ret);
134 		return 1;
135 	}
136 	if (index != 0) {
137 		efi_st_error("WaitForEvent returned wrong index\n");
138 		return 1;
139 	}
140 	efi_st_printf("Counter with TPL level TPL_APPLICATION: %u\n", counter);
141 	if (counter < 8 || counter > 12) {
142 		efi_st_error("Incorrect timing of events\n");
143 		return 1;
144 	}
145 	ret = boottime->set_timer(event_notify, EFI_TIMER_STOP, 0);
146 	if (index != 0) {
147 		efi_st_error("Could not cancel timer\n");
148 		return 1;
149 	}
150 	/* Raise TPL level */
151 	old_tpl = boottime->raise_tpl(TPL_CALLBACK);
152 	if (old_tpl != TPL_APPLICATION) {
153 		efi_st_error("Initial TPL level was not TPL_APPLICATION");
154 		return 1;
155 	}
156 	/* Set 10 ms timer */
157 	counter = 0;
158 	ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
159 	if (index != 0) {
160 		efi_st_error("Could not set timer\n");
161 		return 1;
162 	}
163 	/* Set 100 ms timer */
164 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
165 	if (ret != EFI_SUCCESS) {
166 		efi_st_error("Could not set timer\n");
167 		return 1;
168 	}
169 	do {
170 		ret = boottime->check_event(event_wait);
171 	} while (ret == EFI_NOT_READY);
172 	if (ret != EFI_SUCCESS) {
173 		efi_st_error("Could not check event\n");
174 		return 1;
175 	}
176 	efi_st_printf("Counter with TPL level TPL_CALLBACK: %u\n", counter);
177 	if (counter != 0) {
178 		efi_st_error("Suppressed timer fired\n");
179 		return 1;
180 	}
181 	/* Set 1 ms timer */
182 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000);
183 	if (ret != EFI_SUCCESS) {
184 		efi_st_error("Could not set timer\n");
185 		return 1;
186 	}
187 	/* Restore the old TPL level */
188 	boottime->restore_tpl(TPL_APPLICATION);
189 	ret = boottime->wait_for_event(1, &event_wait, &index);
190 	if (ret != EFI_SUCCESS) {
191 		efi_st_error("Could not wait for event\n");
192 		return 1;
193 	}
194 	efi_st_printf("Counter with TPL level TPL_APPLICATION: %u\n", counter);
195 	if (counter < 1) {
196 		efi_st_error("Queued timer event did not fire\n");
197 		return 1;
198 	}
199 	ret = boottime->set_timer(event_wait, EFI_TIMER_STOP, 0);
200 	if (index != 0) {
201 		efi_st_error("Could not cancel timer\n");
202 		return 1;
203 	}
204 
205 	return 0;
206 }
207 
208 EFI_UNIT_TEST(tpl) = {
209 	.name = "task priority levels",
210 	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
211 	.setup = setup,
212 	.execute = execute,
213 	.teardown = teardown,
214 };
215