1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * efi_selftest_tpl
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 *efi_st_event_notify;
14 static struct efi_event *efi_st_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  */
notify(struct efi_event * event,void * context)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  */
setup(const efi_handle_t handle,const struct efi_system_table * systable)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 				     &efi_st_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_NOTIFY, notify, NULL,
59 				     &efi_st_event_wait);
60 	if (ret != EFI_SUCCESS) {
61 		efi_st_error("could not create event\n");
62 		return EFI_ST_FAILURE;
63 	}
64 	return EFI_ST_SUCCESS;
65 }
66 
67 /*
68  * Tear down unit test.
69  *
70  * Close the events created in setup.
71  *
72  * Return:	EFI_ST_SUCCESS for success
73  */
teardown(void)74 static int teardown(void)
75 {
76 	efi_status_t ret;
77 
78 	if (efi_st_event_notify) {
79 		ret = boottime->close_event(efi_st_event_notify);
80 		efi_st_event_notify = NULL;
81 		if (ret != EFI_SUCCESS) {
82 			efi_st_error("could not close event\n");
83 			return EFI_ST_FAILURE;
84 		}
85 	}
86 	if (efi_st_event_wait) {
87 		ret = boottime->close_event(efi_st_event_wait);
88 		efi_st_event_wait = NULL;
89 		if (ret != EFI_SUCCESS) {
90 			efi_st_error("could not close event\n");
91 			return EFI_ST_FAILURE;
92 		}
93 	}
94 	boottime->restore_tpl(TPL_APPLICATION);
95 	return EFI_ST_SUCCESS;
96 }
97 
98 /*
99  * Execute unit test.
100  *
101  * Run a 10 ms periodic timer and check that it is called 10 times
102  * while waiting for 100 ms single shot timer.
103  *
104  * Raise the TPL level to the level of the 10 ms timer and observe
105  * that the notification function is not called again.
106  *
107  * Lower the TPL level and check that the queued notification
108  * function is called.
109  *
110  * Return:	EFI_ST_SUCCESS for success
111  */
execute(void)112 static int execute(void)
113 {
114 	efi_uintn_t index;
115 	efi_status_t ret;
116 	efi_uintn_t old_tpl;
117 
118 	/* Set 10 ms timer */
119 	notification_count = 0;
120 	ret = boottime->set_timer(efi_st_event_notify, EFI_TIMER_PERIODIC,
121 				  100000);
122 	if (ret != EFI_SUCCESS) {
123 		efi_st_error("Could not set timer\n");
124 		return EFI_ST_FAILURE;
125 	}
126 	/* Set 100 ms timer */
127 	ret = boottime->set_timer(efi_st_event_wait, EFI_TIMER_RELATIVE,
128 				  1000000);
129 	if (ret != EFI_SUCCESS) {
130 		efi_st_error("Could not set timer\n");
131 		return EFI_ST_FAILURE;
132 	}
133 	index = 5;
134 	ret = boottime->wait_for_event(1, &efi_st_event_wait, &index);
135 	if (ret != EFI_SUCCESS) {
136 		efi_st_error("Could not wait for event\n");
137 		return EFI_ST_FAILURE;
138 	}
139 	ret = boottime->check_event(efi_st_event_wait);
140 	if (ret != EFI_NOT_READY) {
141 		efi_st_error("Signaled state was not cleared.\n");
142 		efi_st_printf("ret = %u\n", (unsigned int)ret);
143 		return EFI_ST_FAILURE;
144 	}
145 	if (index != 0) {
146 		efi_st_error("WaitForEvent returned wrong index\n");
147 		return EFI_ST_FAILURE;
148 	}
149 	if (notification_count < 8 || notification_count > 12) {
150 		efi_st_printf(
151 		    "Notification count with TPL level TPL_APPLICATION: %u\n",
152 		    notification_count);
153 		efi_st_error("Incorrect timing of events\n");
154 		return EFI_ST_FAILURE;
155 	}
156 	ret = boottime->set_timer(efi_st_event_notify, EFI_TIMER_STOP, 0);
157 	if (ret != EFI_SUCCESS) {
158 		efi_st_error("Could not cancel timer\n");
159 		return EFI_ST_FAILURE;
160 	}
161 	/* Raise TPL level */
162 	old_tpl = boottime->raise_tpl(TPL_CALLBACK);
163 	if (old_tpl != TPL_APPLICATION) {
164 		efi_st_error("Initial TPL level was not TPL_APPLICATION");
165 		return EFI_ST_FAILURE;
166 	}
167 	/* Set 10 ms timer */
168 	notification_count = 0;
169 	ret = boottime->set_timer(efi_st_event_notify, EFI_TIMER_PERIODIC,
170 				  100000);
171 	if (ret != EFI_SUCCESS) {
172 		efi_st_error("Could not set timer\n");
173 		return EFI_ST_FAILURE;
174 	}
175 	/* Set 100 ms timer */
176 	ret = boottime->set_timer(efi_st_event_wait, EFI_TIMER_RELATIVE,
177 				  1000000);
178 	if (ret != EFI_SUCCESS) {
179 		efi_st_error("Could not set timer\n");
180 		return EFI_ST_FAILURE;
181 	}
182 	do {
183 		ret = boottime->check_event(efi_st_event_wait);
184 	} while (ret == EFI_NOT_READY);
185 	if (ret != EFI_SUCCESS) {
186 		efi_st_error("Could not check event\n");
187 		return EFI_ST_FAILURE;
188 	}
189 	if (notification_count != 0) {
190 		efi_st_printf(
191 			"Notification count with TPL level TPL_CALLBACK: %u\n",
192 			notification_count);
193 		efi_st_error("Suppressed timer fired\n");
194 		return EFI_ST_FAILURE;
195 	}
196 	/* Set 1 ms timer */
197 	ret = boottime->set_timer(efi_st_event_wait, EFI_TIMER_RELATIVE, 1000);
198 	if (ret != EFI_SUCCESS) {
199 		efi_st_error("Could not set timer\n");
200 		return EFI_ST_FAILURE;
201 	}
202 	/* Restore the old TPL level */
203 	boottime->restore_tpl(TPL_APPLICATION);
204 	ret = boottime->wait_for_event(1, &efi_st_event_wait, &index);
205 	if (ret != EFI_SUCCESS) {
206 		efi_st_error("Could not wait for event\n");
207 		return EFI_ST_FAILURE;
208 	}
209 	if (notification_count < 1) {
210 		efi_st_printf(
211 		    "Notification count with TPL level TPL_APPLICATION: %u\n",
212 		    notification_count);
213 		efi_st_error("Queued timer event did not fire\n");
214 		return EFI_ST_FAILURE;
215 	}
216 	ret = boottime->set_timer(efi_st_event_wait, EFI_TIMER_STOP, 0);
217 	if (ret != EFI_SUCCESS) {
218 		efi_st_error("Could not cancel timer\n");
219 		return EFI_ST_FAILURE;
220 	}
221 
222 	return EFI_ST_SUCCESS;
223 }
224 
225 EFI_UNIT_TEST(tpl) = {
226 	.name = "task priority levels",
227 	.phase = EFI_EXECUTE_BEFORE_BOOTTIME_EXIT,
228 	.setup = setup,
229 	.execute = execute,
230 	.teardown = teardown,
231 };
232