1 /*
2 * Copyright (c) 2013 Travis Geiselbrecht
3 *
4 * Use of this source code is governed by a MIT-style
5 * license that can be found in the LICENSE file or at
6 * https://opensource.org/licenses/MIT
7 */
8
9 /*
10 * Global init hook mechanism. Allows code anywhere in the system to define
11 * a init hook that is called at increasing init levels as the system is
12 * initialized.
13 */
14 #include <lk/init.h>
15
16 #include <arch/ops.h>
17 #include <assert.h>
18 #include <lk/compiler.h>
19 #include <lk/debug.h>
20 #include <lk/trace.h>
21
22 #define LOCAL_TRACE 0
23 #define TRACE_INIT (LK_DEBUGLEVEL >= 2)
24 #ifndef EARLIEST_TRACE_LEVEL
25 #define EARLIEST_TRACE_LEVEL LK_INIT_LEVEL_TARGET_EARLY
26 #endif
27
28 extern const struct lk_init_struct __start_lk_init __WEAK;
29 extern const struct lk_init_struct __stop_lk_init __WEAK;
30
lk_init_level(enum lk_init_flags required_flag,uint16_t start_level,uint16_t stop_level)31 void lk_init_level(enum lk_init_flags required_flag, uint16_t start_level, uint16_t stop_level) {
32 LTRACEF("flags %#x, start_level %#hx, stop_level %#hx\n",
33 required_flag, start_level, stop_level);
34
35 ASSERT(start_level > 0);
36 uint16_t last_called_level = start_level - 1;
37 const struct lk_init_struct *last = NULL;
38 for (;;) {
39 /* search for the lowest uncalled hook to call */
40 LTRACEF("last %p, last_called_level %#x\n", last, last_called_level);
41
42 const struct lk_init_struct *found = NULL;
43 bool seen_last = false;
44 for (const struct lk_init_struct *ptr = &__start_lk_init; ptr != &__stop_lk_init; ptr++) {
45 LTRACEF("looking at %p (%s) level %#x, flags %#x, seen_last %d\n", ptr, ptr->name, ptr->level, ptr->flags, seen_last);
46
47 if (ptr == last)
48 seen_last = true;
49
50 /* reject the easy ones */
51 if (!(ptr->flags & required_flag))
52 continue;
53 if (ptr->level > stop_level)
54 continue;
55 if (ptr->level < last_called_level)
56 continue;
57 if (found && found->level <= ptr->level)
58 continue;
59
60 /* keep the lowest one we haven't called yet */
61 if (ptr->level >= start_level && ptr->level > last_called_level) {
62 found = ptr;
63 continue;
64 }
65
66 /* if we're at the same level as the last one we called and we've
67 * already passed over it this time around, we can mark this one
68 * and early terminate the loop.
69 */
70 if (ptr->level == last_called_level && ptr != last && seen_last) {
71 found = ptr;
72 break;
73 }
74 }
75
76 if (!found)
77 break;
78
79 #if TRACE_INIT
80 if (found->level >= EARLIEST_TRACE_LEVEL) {
81 printf("INIT: cpu %d, calling hook %p (%s) at level %#x, flags %#x\n",
82 arch_curr_cpu_num(), found->hook, found->name, found->level, found->flags);
83 }
84 #endif
85 found->hook(found->level);
86 last_called_level = found->level;
87 last = found;
88 }
89 }
90