1 /*
2 * Copyright (c) 2010-2014 Wind River Systems, Inc.
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 */
6
7 /**
8 * @file
9 * @brief Kernel initialization module
10 *
11 * This module contains routines that are used to initialize the kernel.
12 */
13
14 #include <ctype.h>
15 #include <stdbool.h>
16 #include <string.h>
17 #include <offsets_short.h>
18 #include <zephyr/kernel.h>
19 #include <zephyr/sys/printk.h>
20 #include <zephyr/debug/stack.h>
21 #include <zephyr/random/random.h>
22 #include <zephyr/linker/sections.h>
23 #include <zephyr/toolchain.h>
24 #include <zephyr/kernel_structs.h>
25 #include <zephyr/device.h>
26 #include <zephyr/init.h>
27 #include <zephyr/linker/linker-defs.h>
28 #include <zephyr/platform/hooks.h>
29 #include <ksched.h>
30 #include <kthread.h>
31 #include <zephyr/sys/dlist.h>
32 #include <kernel_internal.h>
33 #include <zephyr/drivers/entropy.h>
34 #include <zephyr/logging/log_ctrl.h>
35 #include <zephyr/tracing/tracing.h>
36 #include <zephyr/debug/gcov.h>
37 #include <kswap.h>
38 #include <zephyr/timing/timing.h>
39 #include <zephyr/logging/log.h>
40 #include <zephyr/pm/device_runtime.h>
41 #include <zephyr/internal/syscall_handler.h>
42 LOG_MODULE_REGISTER(os, CONFIG_KERNEL_LOG_LEVEL);
43
44 /* the only struct z_kernel instance */
45 __pinned_bss
46 struct z_kernel _kernel;
47
48 #ifdef CONFIG_PM
49 __pinned_bss atomic_t _cpus_active;
50 #endif
51
52 /* init/main and idle threads */
53 K_THREAD_PINNED_STACK_DEFINE(z_main_stack, CONFIG_MAIN_STACK_SIZE);
54 struct k_thread z_main_thread;
55
56 #ifdef CONFIG_MULTITHREADING
57 __pinned_bss
58 struct k_thread z_idle_threads[CONFIG_MP_MAX_NUM_CPUS];
59
60 static K_KERNEL_PINNED_STACK_ARRAY_DEFINE(z_idle_stacks,
61 CONFIG_MP_MAX_NUM_CPUS,
62 CONFIG_IDLE_STACK_SIZE);
63
z_init_static_threads(void)64 static void z_init_static_threads(void)
65 {
66 STRUCT_SECTION_FOREACH(_static_thread_data, thread_data) {
67 z_setup_new_thread(
68 thread_data->init_thread,
69 thread_data->init_stack,
70 thread_data->init_stack_size,
71 thread_data->init_entry,
72 thread_data->init_p1,
73 thread_data->init_p2,
74 thread_data->init_p3,
75 thread_data->init_prio,
76 thread_data->init_options,
77 thread_data->init_name);
78
79 thread_data->init_thread->init_data = thread_data;
80 }
81
82 #ifdef CONFIG_USERSPACE
83 STRUCT_SECTION_FOREACH(k_object_assignment, pos) {
84 for (int i = 0; pos->objects[i] != NULL; i++) {
85 k_object_access_grant(pos->objects[i],
86 pos->thread);
87 }
88 }
89 #endif /* CONFIG_USERSPACE */
90
91 /*
92 * Non-legacy static threads may be started immediately or
93 * after a previously specified delay. Even though the
94 * scheduler is locked, ticks can still be delivered and
95 * processed. Take a sched lock to prevent them from running
96 * until they are all started.
97 *
98 * Note that static threads defined using the legacy API have a
99 * delay of K_FOREVER.
100 */
101 k_sched_lock();
102 STRUCT_SECTION_FOREACH(_static_thread_data, thread_data) {
103 k_timeout_t init_delay = Z_THREAD_INIT_DELAY(thread_data);
104
105 if (!K_TIMEOUT_EQ(init_delay, K_FOREVER)) {
106 thread_schedule_new(thread_data->init_thread,
107 init_delay);
108 }
109 }
110 k_sched_unlock();
111 }
112 #else
113 #define z_init_static_threads() do { } while (false)
114 #endif /* CONFIG_MULTITHREADING */
115
116 extern const struct init_entry __init_start[];
117 extern const struct init_entry __init_EARLY_start[];
118 extern const struct init_entry __init_PRE_KERNEL_1_start[];
119 extern const struct init_entry __init_PRE_KERNEL_2_start[];
120 extern const struct init_entry __init_POST_KERNEL_start[];
121 extern const struct init_entry __init_APPLICATION_start[];
122 extern const struct init_entry __init_end[];
123
124 enum init_level {
125 INIT_LEVEL_EARLY = 0,
126 INIT_LEVEL_PRE_KERNEL_1,
127 INIT_LEVEL_PRE_KERNEL_2,
128 INIT_LEVEL_POST_KERNEL,
129 INIT_LEVEL_APPLICATION,
130 #ifdef CONFIG_SMP
131 INIT_LEVEL_SMP,
132 #endif /* CONFIG_SMP */
133 };
134
135 #ifdef CONFIG_SMP
136 extern const struct init_entry __init_SMP_start[];
137 #endif /* CONFIG_SMP */
138
139 /*
140 * storage space for the interrupt stack
141 *
142 * Note: This area is used as the system stack during kernel initialization,
143 * since the kernel hasn't yet set up its own stack areas. The dual purposing
144 * of this area is safe since interrupts are disabled until the kernel context
145 * switches to the init thread.
146 */
147 K_KERNEL_PINNED_STACK_ARRAY_DEFINE(z_interrupt_stacks,
148 CONFIG_MP_MAX_NUM_CPUS,
149 CONFIG_ISR_STACK_SIZE);
150
151 extern void idle(void *unused1, void *unused2, void *unused3);
152
153 #ifdef CONFIG_OBJ_CORE_SYSTEM
154 static struct k_obj_type obj_type_cpu;
155 static struct k_obj_type obj_type_kernel;
156
157 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
158 static struct k_obj_core_stats_desc cpu_stats_desc = {
159 .raw_size = sizeof(struct k_cycle_stats),
160 .query_size = sizeof(struct k_thread_runtime_stats),
161 .raw = z_cpu_stats_raw,
162 .query = z_cpu_stats_query,
163 .reset = NULL,
164 .disable = NULL,
165 .enable = NULL,
166 };
167
168 static struct k_obj_core_stats_desc kernel_stats_desc = {
169 .raw_size = sizeof(struct k_cycle_stats) * CONFIG_MP_MAX_NUM_CPUS,
170 .query_size = sizeof(struct k_thread_runtime_stats),
171 .raw = z_kernel_stats_raw,
172 .query = z_kernel_stats_query,
173 .reset = NULL,
174 .disable = NULL,
175 .enable = NULL,
176 };
177 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
178 #endif /* CONFIG_OBJ_CORE_SYSTEM */
179
180 /* LCOV_EXCL_START
181 *
182 * This code is called so early in the boot process that code coverage
183 * doesn't work properly. In addition, not all arches call this code,
184 * some like x86 do this with optimized assembly
185 */
186
187 /**
188 * @brief equivalent of memset() for early boot usage
189 *
190 * Architectures that can't safely use the regular (optimized) memset very
191 * early during boot because e.g. hardware isn't yet sufficiently initialized
192 * may override this with their own safe implementation.
193 */
194 __boot_func
z_early_memset(void * dst,int c,size_t n)195 void __weak z_early_memset(void *dst, int c, size_t n)
196 {
197 (void) memset(dst, c, n);
198 }
199
200 /**
201 * @brief equivalent of memcpy() for early boot usage
202 *
203 * Architectures that can't safely use the regular (optimized) memcpy very
204 * early during boot because e.g. hardware isn't yet sufficiently initialized
205 * may override this with their own safe implementation.
206 */
207 __boot_func
z_early_memcpy(void * dst,const void * src,size_t n)208 void __weak z_early_memcpy(void *dst, const void *src, size_t n)
209 {
210 (void) memcpy(dst, src, n);
211 }
212
213 /**
214 * @brief Clear BSS
215 *
216 * This routine clears the BSS region, so all bytes are 0.
217 */
218 __boot_func
z_bss_zero(void)219 void z_bss_zero(void)
220 {
221 if (IS_ENABLED(CONFIG_SKIP_BSS_CLEAR)) {
222 return;
223 }
224
225 z_early_memset(__bss_start, 0, __bss_end - __bss_start);
226 #if DT_NODE_HAS_STATUS_OKAY(DT_CHOSEN(zephyr_ccm))
227 z_early_memset(&__ccm_bss_start, 0,
228 (uintptr_t) &__ccm_bss_end
229 - (uintptr_t) &__ccm_bss_start);
230 #endif
231 #if DT_NODE_HAS_STATUS_OKAY(DT_CHOSEN(zephyr_dtcm))
232 z_early_memset(&__dtcm_bss_start, 0,
233 (uintptr_t) &__dtcm_bss_end
234 - (uintptr_t) &__dtcm_bss_start);
235 #endif
236 #if DT_NODE_HAS_STATUS_OKAY(DT_CHOSEN(zephyr_ocm))
237 z_early_memset(&__ocm_bss_start, 0,
238 (uintptr_t) &__ocm_bss_end
239 - (uintptr_t) &__ocm_bss_start);
240 #endif
241 #ifdef CONFIG_CODE_DATA_RELOCATION
242 extern void bss_zeroing_relocation(void);
243
244 bss_zeroing_relocation();
245 #endif /* CONFIG_CODE_DATA_RELOCATION */
246 #ifdef CONFIG_COVERAGE_GCOV
247 z_early_memset(&__gcov_bss_start, 0,
248 ((uintptr_t) &__gcov_bss_end - (uintptr_t) &__gcov_bss_start));
249 #endif /* CONFIG_COVERAGE_GCOV */
250 }
251
252 #ifdef CONFIG_LINKER_USE_BOOT_SECTION
253 /**
254 * @brief Clear BSS within the bot region
255 *
256 * This routine clears the BSS within the boot region.
257 * This is separate from z_bss_zero() as boot region may
258 * contain symbols required for the boot process before
259 * paging is initialized.
260 */
261 __boot_func
z_bss_zero_boot(void)262 void z_bss_zero_boot(void)
263 {
264 z_early_memset(&lnkr_boot_bss_start, 0,
265 (uintptr_t)&lnkr_boot_bss_end
266 - (uintptr_t)&lnkr_boot_bss_start);
267 }
268 #endif /* CONFIG_LINKER_USE_BOOT_SECTION */
269
270 #ifdef CONFIG_LINKER_USE_PINNED_SECTION
271 /**
272 * @brief Clear BSS within the pinned region
273 *
274 * This routine clears the BSS within the pinned region.
275 * This is separate from z_bss_zero() as pinned region may
276 * contain symbols required for the boot process before
277 * paging is initialized.
278 */
279 #ifdef CONFIG_LINKER_USE_BOOT_SECTION
280 __boot_func
281 #else
282 __pinned_func
283 #endif /* CONFIG_LINKER_USE_BOOT_SECTION */
z_bss_zero_pinned(void)284 void z_bss_zero_pinned(void)
285 {
286 z_early_memset(&lnkr_pinned_bss_start, 0,
287 (uintptr_t)&lnkr_pinned_bss_end
288 - (uintptr_t)&lnkr_pinned_bss_start);
289 }
290 #endif /* CONFIG_LINKER_USE_PINNED_SECTION */
291
292 #ifdef CONFIG_REQUIRES_STACK_CANARIES
293 #ifdef CONFIG_STACK_CANARIES_TLS
294 extern Z_THREAD_LOCAL volatile uintptr_t __stack_chk_guard;
295 #else
296 extern volatile uintptr_t __stack_chk_guard;
297 #endif /* CONFIG_STACK_CANARIES_TLS */
298 #endif /* CONFIG_REQUIRES_STACK_CANARIES */
299
300 /* LCOV_EXCL_STOP */
301
302 __pinned_bss
303 bool z_sys_post_kernel;
304
do_device_init(const struct device * dev)305 static int do_device_init(const struct device *dev)
306 {
307 int rc = 0;
308
309 if (dev->ops.init != NULL) {
310 rc = dev->ops.init(dev);
311 /* Mark device initialized. If initialization
312 * failed, record the error condition.
313 */
314 if (rc != 0) {
315 if (rc < 0) {
316 rc = -rc;
317 }
318 if (rc > UINT8_MAX) {
319 rc = UINT8_MAX;
320 }
321 dev->state->init_res = rc;
322 }
323 }
324
325 dev->state->initialized = true;
326
327 if (rc == 0) {
328 /* Run automatic device runtime enablement */
329 (void)pm_device_runtime_auto_enable(dev);
330 }
331
332 return rc;
333 }
334
335 /**
336 * @brief Execute all the init entry initialization functions at a given level
337 *
338 * @details Invokes the initialization routine for each init entry object
339 * created by the INIT_ENTRY_DEFINE() macro using the specified level.
340 * The linker script places the init entry objects in memory in the order
341 * they need to be invoked, with symbols indicating where one level leaves
342 * off and the next one begins.
343 *
344 * @param level init level to run.
345 */
z_sys_init_run_level(enum init_level level)346 static void z_sys_init_run_level(enum init_level level)
347 {
348 static const struct init_entry *levels[] = {
349 __init_EARLY_start,
350 __init_PRE_KERNEL_1_start,
351 __init_PRE_KERNEL_2_start,
352 __init_POST_KERNEL_start,
353 __init_APPLICATION_start,
354 #ifdef CONFIG_SMP
355 __init_SMP_start,
356 #endif /* CONFIG_SMP */
357 /* End marker */
358 __init_end,
359 };
360 const struct init_entry *entry;
361
362 for (entry = levels[level]; entry < levels[level+1]; entry++) {
363 const struct device *dev = entry->dev;
364 int result = 0;
365
366 sys_trace_sys_init_enter(entry, level);
367 if (dev != NULL) {
368 if ((dev->flags & DEVICE_FLAG_INIT_DEFERRED) == 0U) {
369 result = do_device_init(dev);
370 }
371 } else {
372 result = entry->init_fn();
373 }
374 sys_trace_sys_init_exit(entry, level, result);
375 }
376 }
377
378
z_impl_device_init(const struct device * dev)379 int z_impl_device_init(const struct device *dev)
380 {
381 if (dev->state->initialized) {
382 return -EALREADY;
383 }
384
385 return do_device_init(dev);
386 }
387
388 #ifdef CONFIG_USERSPACE
z_vrfy_device_init(const struct device * dev)389 static inline int z_vrfy_device_init(const struct device *dev)
390 {
391 K_OOPS(K_SYSCALL_OBJ_INIT(dev, K_OBJ_ANY));
392
393 return z_impl_device_init(dev);
394 }
395 #include <zephyr/syscalls/device_init_mrsh.c>
396 #endif
397
398 extern void boot_banner(void);
399
400 #ifdef CONFIG_BOOTARGS
401 extern const char *get_bootargs(void);
prepare_main_args(int * argc)402 static char **prepare_main_args(int *argc)
403 {
404 #ifdef CONFIG_DYNAMIC_BOOTARGS
405 const char *bootargs = get_bootargs();
406 #else
407 const char bootargs[] = CONFIG_BOOTARGS_STRING;
408 #endif
409
410 /* beginning of the buffer contains argument's strings, end of it contains argvs */
411 static char args_buf[CONFIG_BOOTARGS_ARGS_BUFFER_SIZE];
412 char *strings_end = (char *)args_buf;
413 char **argv_begin = (char **)WB_DN(
414 args_buf + CONFIG_BOOTARGS_ARGS_BUFFER_SIZE - sizeof(char *));
415 int i = 0;
416
417 *argc = 0;
418 *argv_begin = NULL;
419
420 #ifdef CONFIG_DYNAMIC_BOOTARGS
421 if (!bootargs) {
422 return argv_begin;
423 }
424 #endif
425
426 while (1) {
427 while (isspace(bootargs[i])) {
428 i++;
429 }
430
431 if (bootargs[i] == '\0') {
432 return argv_begin;
433 }
434
435 if (strings_end + sizeof(char *) >= (char *)argv_begin) {
436 LOG_WRN("not enough space in args buffer to accommodate all bootargs"
437 " - bootargs truncated");
438 return argv_begin;
439 }
440
441 argv_begin--;
442 memmove(argv_begin, argv_begin + 1, *argc * sizeof(char *));
443 argv_begin[*argc] = strings_end;
444
445 bool quoted = false;
446
447 if (bootargs[i] == '\"' || bootargs[i] == '\'') {
448 char delimiter = bootargs[i];
449
450 for (int j = i + 1; bootargs[j] != '\0'; j++) {
451 if (bootargs[j] == delimiter) {
452 quoted = true;
453 break;
454 }
455 }
456 }
457
458 if (quoted) {
459 char delimiter = bootargs[i];
460
461 i++; /* strip quotes */
462 while (bootargs[i] != delimiter
463 && strings_end < (char *)argv_begin) {
464 *strings_end++ = bootargs[i++];
465 }
466 i++; /* strip quotes */
467 } else {
468 while (!isspace(bootargs[i])
469 && bootargs[i] != '\0'
470 && strings_end < (char *)argv_begin) {
471 *strings_end++ = bootargs[i++];
472 }
473 }
474
475 if (strings_end < (char *)argv_begin) {
476 *strings_end++ = '\0';
477 } else {
478 LOG_WRN("not enough space in args buffer to accommodate all bootargs"
479 " - bootargs truncated");
480 argv_begin[*argc] = NULL;
481 return argv_begin;
482 }
483 (*argc)++;
484 }
485 }
486 #endif
487
488 /**
489 * @brief Mainline for kernel's background thread
490 *
491 * This routine completes kernel initialization by invoking the remaining
492 * init functions, then invokes application's main() routine.
493 */
494 __boot_func
bg_thread_main(void * unused1,void * unused2,void * unused3)495 static void bg_thread_main(void *unused1, void *unused2, void *unused3)
496 {
497 ARG_UNUSED(unused1);
498 ARG_UNUSED(unused2);
499 ARG_UNUSED(unused3);
500
501 #ifdef CONFIG_MMU
502 /* Invoked here such that backing store or eviction algorithms may
503 * initialize kernel objects, and that all POST_KERNEL and later tasks
504 * may perform memory management tasks (except for
505 * k_mem_map_phys_bare() which is allowed at any time)
506 */
507 z_mem_manage_init();
508 #endif /* CONFIG_MMU */
509 z_sys_post_kernel = true;
510
511 #if CONFIG_IRQ_OFFLOAD
512 arch_irq_offload_init();
513 #endif
514 z_sys_init_run_level(INIT_LEVEL_POST_KERNEL);
515 #if CONFIG_SOC_LATE_INIT_HOOK
516 soc_late_init_hook();
517 #endif
518 #if CONFIG_BOARD_LATE_INIT_HOOK
519 board_late_init_hook();
520 #endif
521
522 #if defined(CONFIG_STACK_POINTER_RANDOM) && (CONFIG_STACK_POINTER_RANDOM != 0)
523 z_stack_adjust_initialized = 1;
524 #endif /* CONFIG_STACK_POINTER_RANDOM */
525 boot_banner();
526
527 void z_init_static(void);
528 z_init_static();
529
530 /* Final init level before app starts */
531 z_sys_init_run_level(INIT_LEVEL_APPLICATION);
532
533 z_init_static_threads();
534
535 #ifdef CONFIG_KERNEL_COHERENCE
536 __ASSERT_NO_MSG(arch_mem_coherent(&_kernel));
537 #endif /* CONFIG_KERNEL_COHERENCE */
538
539 #ifdef CONFIG_SMP
540 if (!IS_ENABLED(CONFIG_SMP_BOOT_DELAY)) {
541 z_smp_init();
542 }
543 z_sys_init_run_level(INIT_LEVEL_SMP);
544 #endif /* CONFIG_SMP */
545
546 #ifdef CONFIG_MMU
547 z_mem_manage_boot_finish();
548 #endif /* CONFIG_MMU */
549
550 #ifdef CONFIG_BOOTARGS
551 extern int main(int, char **);
552
553 int argc = 0;
554 char **argv = prepare_main_args(&argc);
555 (void)main(argc, argv);
556 #else
557 extern int main(void);
558
559 (void)main();
560 #endif /* CONFIG_BOOTARGS */
561
562 /* Mark non-essential since main() has no more work to do */
563 z_thread_essential_clear(&z_main_thread);
564
565 #ifdef CONFIG_COVERAGE_DUMP
566 /* Dump coverage data once the main() has exited. */
567 gcov_coverage_dump();
568 #endif /* CONFIG_COVERAGE_DUMP */
569 } /* LCOV_EXCL_LINE ... because we just dumped final coverage data */
570
571 #if defined(CONFIG_MULTITHREADING)
572 __boot_func
init_idle_thread(int i)573 static void init_idle_thread(int i)
574 {
575 struct k_thread *thread = &z_idle_threads[i];
576 k_thread_stack_t *stack = z_idle_stacks[i];
577 size_t stack_size = K_KERNEL_STACK_SIZEOF(z_idle_stacks[i]);
578
579 #ifdef CONFIG_THREAD_NAME
580
581 #if CONFIG_MP_MAX_NUM_CPUS > 1
582 char tname[8];
583 snprintk(tname, 8, "idle %02d", i);
584 #else
585 char *tname = "idle";
586 #endif /* CONFIG_MP_MAX_NUM_CPUS */
587
588 #else
589 char *tname = NULL;
590 #endif /* CONFIG_THREAD_NAME */
591
592 z_setup_new_thread(thread, stack,
593 stack_size, idle, &_kernel.cpus[i],
594 NULL, NULL, K_IDLE_PRIO, K_ESSENTIAL,
595 tname);
596 z_mark_thread_as_not_sleeping(thread);
597
598 #ifdef CONFIG_SMP
599 thread->base.is_idle = 1U;
600 #endif /* CONFIG_SMP */
601 }
602
z_init_cpu(int id)603 void z_init_cpu(int id)
604 {
605 init_idle_thread(id);
606 _kernel.cpus[id].idle_thread = &z_idle_threads[id];
607 _kernel.cpus[id].id = id;
608 _kernel.cpus[id].irq_stack =
609 (K_KERNEL_STACK_BUFFER(z_interrupt_stacks[id]) +
610 K_KERNEL_STACK_SIZEOF(z_interrupt_stacks[id]));
611 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL
612 _kernel.cpus[id].usage = &_kernel.usage[id];
613 _kernel.cpus[id].usage->track_usage =
614 CONFIG_SCHED_THREAD_USAGE_AUTO_ENABLE;
615 #endif
616
617 #ifdef CONFIG_PM
618 /*
619 * Increment number of CPUs active. The pm subsystem
620 * will keep track of this from here.
621 */
622 atomic_inc(&_cpus_active);
623 #endif
624
625 #ifdef CONFIG_OBJ_CORE_SYSTEM
626 k_obj_core_init_and_link(K_OBJ_CORE(&_kernel.cpus[id]), &obj_type_cpu);
627 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
628 k_obj_core_stats_register(K_OBJ_CORE(&_kernel.cpus[id]),
629 _kernel.cpus[id].usage,
630 sizeof(struct k_cycle_stats));
631 #endif
632 #endif
633 }
634
635 /**
636 *
637 * @brief Initializes kernel data structures
638 *
639 * This routine initializes various kernel data structures, including
640 * the init and idle threads and any architecture-specific initialization.
641 *
642 * Note that all fields of "_kernel" are set to zero on entry, which may
643 * be all the initialization many of them require.
644 *
645 * @return initial stack pointer for the main thread
646 */
647 __boot_func
prepare_multithreading(void)648 static char *prepare_multithreading(void)
649 {
650 char *stack_ptr;
651
652 /* _kernel.ready_q is all zeroes */
653 z_sched_init();
654
655 #ifndef CONFIG_SMP
656 /*
657 * prime the cache with the main thread since:
658 *
659 * - the cache can never be NULL
660 * - the main thread will be the one to run first
661 * - no other thread is initialized yet and thus their priority fields
662 * contain garbage, which would prevent the cache loading algorithm
663 * to work as intended
664 */
665 _kernel.ready_q.cache = &z_main_thread;
666 #endif /* CONFIG_SMP */
667 stack_ptr = z_setup_new_thread(&z_main_thread, z_main_stack,
668 K_THREAD_STACK_SIZEOF(z_main_stack),
669 bg_thread_main,
670 NULL, NULL, NULL,
671 CONFIG_MAIN_THREAD_PRIORITY,
672 K_ESSENTIAL, "main");
673 z_mark_thread_as_not_sleeping(&z_main_thread);
674 z_ready_thread(&z_main_thread);
675
676 z_init_cpu(0);
677
678 return stack_ptr;
679 }
680
681 __boot_func
switch_to_main_thread(char * stack_ptr)682 static FUNC_NORETURN void switch_to_main_thread(char *stack_ptr)
683 {
684 #ifdef CONFIG_ARCH_HAS_CUSTOM_SWAP_TO_MAIN
685 arch_switch_to_main_thread(&z_main_thread, stack_ptr, bg_thread_main);
686 #else
687 ARG_UNUSED(stack_ptr);
688 /*
689 * Context switch to main task (entry function is _main()): the
690 * current fake thread is not on a wait queue or ready queue, so it
691 * will never be rescheduled in.
692 */
693 z_swap_unlocked();
694 #endif /* CONFIG_ARCH_HAS_CUSTOM_SWAP_TO_MAIN */
695 CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
696 }
697 #endif /* CONFIG_MULTITHREADING */
698
699 __boot_func
z_early_rand_get(uint8_t * buf,size_t length)700 void __weak z_early_rand_get(uint8_t *buf, size_t length)
701 {
702 static uint64_t state = (uint64_t)CONFIG_TIMER_RANDOM_INITIAL_STATE;
703 int rc;
704
705 #ifdef CONFIG_ENTROPY_HAS_DRIVER
706 const struct device *const entropy = DEVICE_DT_GET_OR_NULL(DT_CHOSEN(zephyr_entropy));
707
708 if ((entropy != NULL) && device_is_ready(entropy)) {
709 /* Try to see if driver provides an ISR-specific API */
710 rc = entropy_get_entropy_isr(entropy, buf, length, ENTROPY_BUSYWAIT);
711 if (rc > 0) {
712 length -= rc;
713 buf += rc;
714 }
715 }
716 #endif /* CONFIG_ENTROPY_HAS_DRIVER */
717
718 while (length > 0) {
719 uint32_t val;
720
721 state = state + k_cycle_get_32();
722 state = state * 2862933555777941757ULL + 3037000493ULL;
723 val = (uint32_t)(state >> 32);
724 rc = MIN(length, sizeof(val));
725 z_early_memcpy((void *)buf, &val, rc);
726
727 length -= rc;
728 buf += rc;
729 }
730 }
731
732 /**
733 *
734 * @brief Initialize kernel
735 *
736 * This routine is invoked when the system is ready to run C code. The
737 * processor must be running in 32-bit mode, and the BSS must have been
738 * cleared/zeroed.
739 *
740 * @return Does not return
741 */
742 __boot_func
743 FUNC_NO_STACK_PROTECTOR
z_cstart(void)744 FUNC_NORETURN void z_cstart(void)
745 {
746 /* gcov hook needed to get the coverage report.*/
747 gcov_static_init();
748
749 /* initialize early init calls */
750 z_sys_init_run_level(INIT_LEVEL_EARLY);
751
752 /* perform any architecture-specific initialization */
753 arch_kernel_init();
754
755 LOG_CORE_INIT();
756
757 #if defined(CONFIG_MULTITHREADING)
758 z_dummy_thread_init(&_thread_dummy);
759 #endif /* CONFIG_MULTITHREADING */
760 /* do any necessary initialization of static devices */
761 z_device_state_init();
762
763 #if CONFIG_SOC_EARLY_INIT_HOOK
764 soc_early_init_hook();
765 #endif
766 #if CONFIG_BOARD_EARLY_INIT_HOOK
767 board_early_init_hook();
768 #endif
769 /* perform basic hardware initialization */
770 z_sys_init_run_level(INIT_LEVEL_PRE_KERNEL_1);
771 #if defined(CONFIG_SMP)
772 arch_smp_init();
773 #endif
774 z_sys_init_run_level(INIT_LEVEL_PRE_KERNEL_2);
775
776 #ifdef CONFIG_REQUIRES_STACK_CANARIES
777 uintptr_t stack_guard;
778
779 z_early_rand_get((uint8_t *)&stack_guard, sizeof(stack_guard));
780 __stack_chk_guard = stack_guard;
781 __stack_chk_guard <<= 8;
782 #endif /* CONFIG_REQUIRES_STACK_CANARIES */
783
784 #ifdef CONFIG_TIMING_FUNCTIONS_NEED_AT_BOOT
785 timing_init();
786 timing_start();
787 #endif /* CONFIG_TIMING_FUNCTIONS_NEED_AT_BOOT */
788
789 #ifdef CONFIG_MULTITHREADING
790 switch_to_main_thread(prepare_multithreading());
791 #else
792 #ifdef ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING
793 /* Custom ARCH-specific routine to switch to main()
794 * in the case of no multi-threading.
795 */
796 ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING(bg_thread_main,
797 NULL, NULL, NULL);
798 #else
799 bg_thread_main(NULL, NULL, NULL);
800
801 /* LCOV_EXCL_START
802 * We've already dumped coverage data at this point.
803 */
804 irq_lock();
805 while (true) {
806 }
807 /* LCOV_EXCL_STOP */
808 #endif /* ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING */
809 #endif /* CONFIG_MULTITHREADING */
810
811 /*
812 * Compiler can't tell that the above routines won't return and issues
813 * a warning unless we explicitly tell it that control never gets this
814 * far.
815 */
816
817 CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
818 }
819
820 #ifdef CONFIG_OBJ_CORE_SYSTEM
init_cpu_obj_core_list(void)821 static int init_cpu_obj_core_list(void)
822 {
823 /* Initialize CPU object type */
824
825 z_obj_type_init(&obj_type_cpu, K_OBJ_TYPE_CPU_ID,
826 offsetof(struct _cpu, obj_core));
827
828 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
829 k_obj_type_stats_init(&obj_type_cpu, &cpu_stats_desc);
830 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
831
832 return 0;
833 }
834
init_kernel_obj_core_list(void)835 static int init_kernel_obj_core_list(void)
836 {
837 /* Initialize kernel object type */
838
839 z_obj_type_init(&obj_type_kernel, K_OBJ_TYPE_KERNEL_ID,
840 offsetof(struct z_kernel, obj_core));
841
842 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
843 k_obj_type_stats_init(&obj_type_kernel, &kernel_stats_desc);
844 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
845
846 k_obj_core_init_and_link(K_OBJ_CORE(&_kernel), &obj_type_kernel);
847 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
848 k_obj_core_stats_register(K_OBJ_CORE(&_kernel), _kernel.usage,
849 sizeof(_kernel.usage));
850 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
851
852 return 0;
853 }
854
855 SYS_INIT(init_cpu_obj_core_list, PRE_KERNEL_1,
856 CONFIG_KERNEL_INIT_PRIORITY_OBJECTS);
857
858 SYS_INIT(init_kernel_obj_core_list, PRE_KERNEL_1,
859 CONFIG_KERNEL_INIT_PRIORITY_OBJECTS);
860 #endif /* CONFIG_OBJ_CORE_SYSTEM */
861
