1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * efi_selftest_events
4  *
5  * Copyright (c) 2017 Heinrich Schuchardt <xypron.glpk@gmx.de>
6  *
7  * This unit test uses timer events to check the handling of
8  * task priority levels.
9  */
10 
11 #include <efi_selftest.h>
12 
13 static struct efi_event *event_notify;
14 static struct efi_event *event_wait;
15 static unsigned int notification_count;
16 static struct efi_boot_services *boottime;
17 
18 /*
19  * Notification function, increments the notification count.
20  *
21  * @event	notified event
22  * @context	pointer to the notification count
23  */
24 static void EFIAPI notify(struct efi_event *event, void *context)
25 {
26 	unsigned int *count = context;
27 
28 	if (count)
29 		++*count;
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  * @return:	EFI_ST_SUCCESS for success
41  */
42 static int setup(const efi_handle_t handle,
43 		 const struct efi_system_table *systable)
44 {
45 	efi_status_t ret;
46 
47 	boottime = systable->boottime;
48 
49 	ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_SIGNAL,
50 				     TPL_CALLBACK, notify,
51 				     (void *)&notification_count,
52 				     &event_notify);
53 	if (ret != EFI_SUCCESS) {
54 		efi_st_error("could not create event\n");
55 		return EFI_ST_FAILURE;
56 	}
57 	ret = boottime->create_event(EVT_TIMER | EVT_NOTIFY_WAIT,
58 				     TPL_HIGH_LEVEL, notify, NULL, &event_wait);
59 	if (ret != EFI_SUCCESS) {
60 		efi_st_error("could not create event\n");
61 		return EFI_ST_FAILURE;
62 	}
63 	return EFI_ST_SUCCESS;
64 }
65 
66 /*
67  * Tear down unit test.
68  *
69  * Close the events created in setup.
70  *
71  * @return:	EFI_ST_SUCCESS for success
72  */
73 static int teardown(void)
74 {
75 	efi_status_t ret;
76 
77 	if (event_notify) {
78 		ret = boottime->close_event(event_notify);
79 		event_notify = NULL;
80 		if (ret != EFI_SUCCESS) {
81 			efi_st_error("could not close event\n");
82 			return EFI_ST_FAILURE;
83 		}
84 	}
85 	if (event_wait) {
86 		ret = boottime->close_event(event_wait);
87 		event_wait = NULL;
88 		if (ret != EFI_SUCCESS) {
89 			efi_st_error("could not close event\n");
90 			return EFI_ST_FAILURE;
91 		}
92 	}
93 	boottime->restore_tpl(TPL_APPLICATION);
94 	return EFI_ST_SUCCESS;
95 }
96 
97 /*
98  * Execute unit test.
99  *
100  * Run a 10 ms periodic timer and check that it is called 10 times
101  * while waiting for 100 ms single shot timer.
102  *
103  * Raise the TPL level to the level of the 10 ms timer and observe
104  * that the notification function is not called again.
105  *
106  * Lower the TPL level and check that the queued notification
107  * function is called.
108  *
109  * @return:	EFI_ST_SUCCESS for success
110  */
111 static int execute(void)
112 {
113 	efi_uintn_t index;
114 	efi_status_t ret;
115 	efi_uintn_t old_tpl;
116 
117 	/* Set 10 ms timer */
118 	notification_count = 0;
119 	ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
120 	if (ret != EFI_SUCCESS) {
121 		efi_st_error("Could not set timer\n");
122 		return EFI_ST_FAILURE;
123 	}
124 	/* Set 100 ms timer */
125 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
126 	if (ret != EFI_SUCCESS) {
127 		efi_st_error("Could not set timer\n");
128 		return EFI_ST_FAILURE;
129 	}
130 	index = 5;
131 	ret = boottime->wait_for_event(1, &event_wait, &index);
132 	if (ret != EFI_SUCCESS) {
133 		efi_st_error("Could not wait for event\n");
134 		return EFI_ST_FAILURE;
135 	}
136 	ret = boottime->check_event(event_wait);
137 	if (ret != EFI_NOT_READY) {
138 		efi_st_error("Signaled state was not cleared.\n");
139 		efi_st_printf("ret = %u\n", (unsigned int)ret);
140 		return EFI_ST_FAILURE;
141 	}
142 	if (index != 0) {
143 		efi_st_error("WaitForEvent returned wrong index\n");
144 		return EFI_ST_FAILURE;
145 	}
146 	if (notification_count < 8 || notification_count > 12) {
147 		efi_st_printf(
148 		    "Notification count with TPL level TPL_APPLICATION: %u\n",
149 		    notification_count);
150 		efi_st_error("Incorrect timing of events\n");
151 		return EFI_ST_FAILURE;
152 	}
153 	ret = boottime->set_timer(event_notify, EFI_TIMER_STOP, 0);
154 	if (index != 0) {
155 		efi_st_error("Could not cancel timer\n");
156 		return EFI_ST_FAILURE;
157 	}
158 	/* Raise TPL level */
159 	old_tpl = boottime->raise_tpl(TPL_CALLBACK);
160 	if (old_tpl != TPL_APPLICATION) {
161 		efi_st_error("Initial TPL level was not TPL_APPLICATION");
162 		return EFI_ST_FAILURE;
163 	}
164 	/* Set 10 ms timer */
165 	notification_count = 0;
166 	ret = boottime->set_timer(event_notify, EFI_TIMER_PERIODIC, 100000);
167 	if (index != 0) {
168 		efi_st_error("Could not set timer\n");
169 		return EFI_ST_FAILURE;
170 	}
171 	/* Set 100 ms timer */
172 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000000);
173 	if (ret != EFI_SUCCESS) {
174 		efi_st_error("Could not set timer\n");
175 		return EFI_ST_FAILURE;
176 	}
177 	do {
178 		ret = boottime->check_event(event_wait);
179 	} while (ret == EFI_NOT_READY);
180 	if (ret != EFI_SUCCESS) {
181 		efi_st_error("Could not check event\n");
182 		return EFI_ST_FAILURE;
183 	}
184 	if (notification_count != 0) {
185 		efi_st_printf(
186 			"Notification count with TPL level TPL_CALLBACK: %u\n",
187 			notification_count);
188 		efi_st_error("Suppressed timer fired\n");
189 		return EFI_ST_FAILURE;
190 	}
191 	/* Set 1 ms timer */
192 	ret = boottime->set_timer(event_wait, EFI_TIMER_RELATIVE, 1000);
193 	if (ret != EFI_SUCCESS) {
194 		efi_st_error("Could not set timer\n");
195 		return EFI_ST_FAILURE;
196 	}
197 	/* Restore the old TPL level */
198 	boottime->restore_tpl(TPL_APPLICATION);
199 	ret = boottime->wait_for_event(1, &event_wait, &index);
200 	if (ret != EFI_SUCCESS) {
201 		efi_st_error("Could not wait for event\n");
202 		return EFI_ST_FAILURE;
203 	}
204 	if (notification_count < 1) {
205 		efi_st_printf(
206 		    "Notification count with TPL level TPL_APPLICATION: %u\n",
207 		    notification_count);
208 		efi_st_error("Queued timer event did not fire\n");
209 		return EFI_ST_FAILURE;
210 	}
211 	ret = boottime->set_timer(event_wait, EFI_TIMER_STOP, 0);
212 	if (ret != EFI_SUCCESS) {
213 		efi_st_error("Could not cancel timer\n");
214 		return EFI_ST_FAILURE;
215 	}
216 
217 	return EFI_ST_SUCCESS;
218 }
219 
220 EFI_UNIT_TEST(tpl) = {
221 	.name = "task priority levels",
222 	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
223 	.setup = setup,
224 	.execute = execute,
225 	.teardown = teardown,
226 };
227