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 init_entry * entry)305 static int do_device_init(const struct init_entry *entry)
306 {
307 const struct device *dev = entry->dev;
308 int rc = 0;
309
310 if (entry->init_fn.dev != NULL) {
311 rc = entry->init_fn.dev(dev);
312 /* Mark device initialized. If initialization
313 * failed, record the error condition.
314 */
315 if (rc != 0) {
316 if (rc < 0) {
317 rc = -rc;
318 }
319 if (rc > UINT8_MAX) {
320 rc = UINT8_MAX;
321 }
322 dev->state->init_res = rc;
323 }
324 }
325
326 dev->state->initialized = true;
327
328 if (rc == 0) {
329 /* Run automatic device runtime enablement */
330 (void)pm_device_runtime_auto_enable(dev);
331 }
332
333 return rc;
334 }
335
336 /**
337 * @brief Execute all the init entry initialization functions at a given level
338 *
339 * @details Invokes the initialization routine for each init entry object
340 * created by the INIT_ENTRY_DEFINE() macro using the specified level.
341 * The linker script places the init entry objects in memory in the order
342 * they need to be invoked, with symbols indicating where one level leaves
343 * off and the next one begins.
344 *
345 * @param level init level to run.
346 */
z_sys_init_run_level(enum init_level level)347 static void z_sys_init_run_level(enum init_level level)
348 {
349 static const struct init_entry *levels[] = {
350 __init_EARLY_start,
351 __init_PRE_KERNEL_1_start,
352 __init_PRE_KERNEL_2_start,
353 __init_POST_KERNEL_start,
354 __init_APPLICATION_start,
355 #ifdef CONFIG_SMP
356 __init_SMP_start,
357 #endif /* CONFIG_SMP */
358 /* End marker */
359 __init_end,
360 };
361 const struct init_entry *entry;
362
363 for (entry = levels[level]; entry < levels[level+1]; entry++) {
364 const struct device *dev = entry->dev;
365 int result;
366
367 sys_trace_sys_init_enter(entry, level);
368 if (dev != NULL) {
369 result = do_device_init(entry);
370 } else {
371 result = entry->init_fn.sys();
372 }
373 sys_trace_sys_init_exit(entry, level, result);
374 }
375 }
376
377
z_impl_device_init(const struct device * dev)378 int z_impl_device_init(const struct device *dev)
379 {
380 if (dev == NULL) {
381 return -ENOENT;
382 }
383
384 STRUCT_SECTION_FOREACH_ALTERNATE(_deferred_init, init_entry, entry) {
385 if (entry->dev == dev) {
386 return do_device_init(entry);
387 }
388 }
389
390 return -ENOENT;
391 }
392
393 #ifdef CONFIG_USERSPACE
z_vrfy_device_init(const struct device * dev)394 static inline int z_vrfy_device_init(const struct device *dev)
395 {
396 K_OOPS(K_SYSCALL_OBJ_INIT(dev, K_OBJ_ANY));
397
398 return z_impl_device_init(dev);
399 }
400 #include <zephyr/syscalls/device_init_mrsh.c>
401 #endif
402
403 extern void boot_banner(void);
404
405 #ifdef CONFIG_BOOTARGS
406 extern const char *get_bootargs(void);
prepare_main_args(int * argc)407 static char **prepare_main_args(int *argc)
408 {
409 #ifdef CONFIG_DYNAMIC_BOOTARGS
410 const char *bootargs = get_bootargs();
411 #else
412 const char bootargs[] = CONFIG_BOOTARGS_STRING;
413 #endif
414
415 /* beginning of the buffer contains argument's strings, end of it contains argvs */
416 static char args_buf[CONFIG_BOOTARGS_ARGS_BUFFER_SIZE];
417 char *strings_end = (char *)args_buf;
418 char **argv_begin = (char **)WB_DN(
419 args_buf + CONFIG_BOOTARGS_ARGS_BUFFER_SIZE - sizeof(char *));
420 int i = 0;
421
422 *argc = 0;
423 *argv_begin = NULL;
424
425 #ifdef CONFIG_DYNAMIC_BOOTARGS
426 if (!bootargs) {
427 return argv_begin;
428 }
429 #endif
430
431 while (1) {
432 while (isspace(bootargs[i])) {
433 i++;
434 }
435
436 if (bootargs[i] == '\0') {
437 return argv_begin;
438 }
439
440 if (strings_end + sizeof(char *) >= (char *)argv_begin) {
441 LOG_WRN("not enough space in args buffer to accommodate all bootargs"
442 " - bootargs truncated");
443 return argv_begin;
444 }
445
446 argv_begin--;
447 memmove(argv_begin, argv_begin + 1, *argc * sizeof(char *));
448 argv_begin[*argc] = strings_end;
449
450 bool quoted = false;
451
452 if (bootargs[i] == '\"' || bootargs[i] == '\'') {
453 char delimiter = bootargs[i];
454
455 for (int j = i + 1; bootargs[j] != '\0'; j++) {
456 if (bootargs[j] == delimiter) {
457 quoted = true;
458 break;
459 }
460 }
461 }
462
463 if (quoted) {
464 char delimiter = bootargs[i];
465
466 i++; /* strip quotes */
467 while (bootargs[i] != delimiter
468 && strings_end < (char *)argv_begin) {
469 *strings_end++ = bootargs[i++];
470 }
471 i++; /* strip quotes */
472 } else {
473 while (!isspace(bootargs[i])
474 && bootargs[i] != '\0'
475 && strings_end < (char *)argv_begin) {
476 *strings_end++ = bootargs[i++];
477 }
478 }
479
480 if (strings_end < (char *)argv_begin) {
481 *strings_end++ = '\0';
482 } else {
483 LOG_WRN("not enough space in args buffer to accommodate all bootargs"
484 " - bootargs truncated");
485 argv_begin[*argc] = NULL;
486 return argv_begin;
487 }
488 (*argc)++;
489 }
490 }
491 #endif
492
493 /**
494 * @brief Mainline for kernel's background thread
495 *
496 * This routine completes kernel initialization by invoking the remaining
497 * init functions, then invokes application's main() routine.
498 */
499 __boot_func
bg_thread_main(void * unused1,void * unused2,void * unused3)500 static void bg_thread_main(void *unused1, void *unused2, void *unused3)
501 {
502 ARG_UNUSED(unused1);
503 ARG_UNUSED(unused2);
504 ARG_UNUSED(unused3);
505
506 #ifdef CONFIG_MMU
507 /* Invoked here such that backing store or eviction algorithms may
508 * initialize kernel objects, and that all POST_KERNEL and later tasks
509 * may perform memory management tasks (except for
510 * k_mem_map_phys_bare() which is allowed at any time)
511 */
512 z_mem_manage_init();
513 #endif /* CONFIG_MMU */
514 z_sys_post_kernel = true;
515
516 #if CONFIG_IRQ_OFFLOAD
517 arch_irq_offload_init();
518 #endif
519 z_sys_init_run_level(INIT_LEVEL_POST_KERNEL);
520 #if CONFIG_SOC_LATE_INIT_HOOK
521 soc_late_init_hook();
522 #endif
523 #if CONFIG_BOARD_LATE_INIT_HOOK
524 board_late_init_hook();
525 #endif
526
527 #if defined(CONFIG_STACK_POINTER_RANDOM) && (CONFIG_STACK_POINTER_RANDOM != 0)
528 z_stack_adjust_initialized = 1;
529 #endif /* CONFIG_STACK_POINTER_RANDOM */
530 boot_banner();
531
532 void z_init_static(void);
533 z_init_static();
534
535 /* Final init level before app starts */
536 z_sys_init_run_level(INIT_LEVEL_APPLICATION);
537
538 z_init_static_threads();
539
540 #ifdef CONFIG_KERNEL_COHERENCE
541 __ASSERT_NO_MSG(arch_mem_coherent(&_kernel));
542 #endif /* CONFIG_KERNEL_COHERENCE */
543
544 #ifdef CONFIG_SMP
545 if (!IS_ENABLED(CONFIG_SMP_BOOT_DELAY)) {
546 z_smp_init();
547 }
548 z_sys_init_run_level(INIT_LEVEL_SMP);
549 #endif /* CONFIG_SMP */
550
551 #ifdef CONFIG_MMU
552 z_mem_manage_boot_finish();
553 #endif /* CONFIG_MMU */
554
555 #ifdef CONFIG_BOOTARGS
556 extern int main(int, char **);
557
558 int argc = 0;
559 char **argv = prepare_main_args(&argc);
560 (void)main(argc, argv);
561 #else
562 extern int main(void);
563
564 (void)main();
565 #endif /* CONFIG_BOOTARGS */
566
567 /* Mark non-essential since main() has no more work to do */
568 z_thread_essential_clear(&z_main_thread);
569
570 #ifdef CONFIG_COVERAGE_DUMP
571 /* Dump coverage data once the main() has exited. */
572 gcov_coverage_dump();
573 #endif /* CONFIG_COVERAGE_DUMP */
574 } /* LCOV_EXCL_LINE ... because we just dumped final coverage data */
575
576 #if defined(CONFIG_MULTITHREADING)
577 __boot_func
init_idle_thread(int i)578 static void init_idle_thread(int i)
579 {
580 struct k_thread *thread = &z_idle_threads[i];
581 k_thread_stack_t *stack = z_idle_stacks[i];
582 size_t stack_size = K_KERNEL_STACK_SIZEOF(z_idle_stacks[i]);
583
584 #ifdef CONFIG_THREAD_NAME
585
586 #if CONFIG_MP_MAX_NUM_CPUS > 1
587 char tname[8];
588 snprintk(tname, 8, "idle %02d", i);
589 #else
590 char *tname = "idle";
591 #endif /* CONFIG_MP_MAX_NUM_CPUS */
592
593 #else
594 char *tname = NULL;
595 #endif /* CONFIG_THREAD_NAME */
596
597 z_setup_new_thread(thread, stack,
598 stack_size, idle, &_kernel.cpus[i],
599 NULL, NULL, K_IDLE_PRIO, K_ESSENTIAL,
600 tname);
601 z_mark_thread_as_not_sleeping(thread);
602
603 #ifdef CONFIG_SMP
604 thread->base.is_idle = 1U;
605 #endif /* CONFIG_SMP */
606 }
607
z_init_cpu(int id)608 void z_init_cpu(int id)
609 {
610 init_idle_thread(id);
611 _kernel.cpus[id].idle_thread = &z_idle_threads[id];
612 _kernel.cpus[id].id = id;
613 _kernel.cpus[id].irq_stack =
614 (K_KERNEL_STACK_BUFFER(z_interrupt_stacks[id]) +
615 K_KERNEL_STACK_SIZEOF(z_interrupt_stacks[id]));
616 #ifdef CONFIG_SCHED_THREAD_USAGE_ALL
617 _kernel.cpus[id].usage = &_kernel.usage[id];
618 _kernel.cpus[id].usage->track_usage =
619 CONFIG_SCHED_THREAD_USAGE_AUTO_ENABLE;
620 #endif
621
622 #ifdef CONFIG_PM
623 /*
624 * Increment number of CPUs active. The pm subsystem
625 * will keep track of this from here.
626 */
627 atomic_inc(&_cpus_active);
628 #endif
629
630 #ifdef CONFIG_OBJ_CORE_SYSTEM
631 k_obj_core_init_and_link(K_OBJ_CORE(&_kernel.cpus[id]), &obj_type_cpu);
632 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
633 k_obj_core_stats_register(K_OBJ_CORE(&_kernel.cpus[id]),
634 _kernel.cpus[id].usage,
635 sizeof(struct k_cycle_stats));
636 #endif
637 #endif
638 }
639
640 /**
641 *
642 * @brief Initializes kernel data structures
643 *
644 * This routine initializes various kernel data structures, including
645 * the init and idle threads and any architecture-specific initialization.
646 *
647 * Note that all fields of "_kernel" are set to zero on entry, which may
648 * be all the initialization many of them require.
649 *
650 * @return initial stack pointer for the main thread
651 */
652 __boot_func
prepare_multithreading(void)653 static char *prepare_multithreading(void)
654 {
655 char *stack_ptr;
656
657 /* _kernel.ready_q is all zeroes */
658 z_sched_init();
659
660 #ifndef CONFIG_SMP
661 /*
662 * prime the cache with the main thread since:
663 *
664 * - the cache can never be NULL
665 * - the main thread will be the one to run first
666 * - no other thread is initialized yet and thus their priority fields
667 * contain garbage, which would prevent the cache loading algorithm
668 * to work as intended
669 */
670 _kernel.ready_q.cache = &z_main_thread;
671 #endif /* CONFIG_SMP */
672 stack_ptr = z_setup_new_thread(&z_main_thread, z_main_stack,
673 K_THREAD_STACK_SIZEOF(z_main_stack),
674 bg_thread_main,
675 NULL, NULL, NULL,
676 CONFIG_MAIN_THREAD_PRIORITY,
677 K_ESSENTIAL, "main");
678 z_mark_thread_as_not_sleeping(&z_main_thread);
679 z_ready_thread(&z_main_thread);
680
681 z_init_cpu(0);
682
683 return stack_ptr;
684 }
685
686 __boot_func
switch_to_main_thread(char * stack_ptr)687 static FUNC_NORETURN void switch_to_main_thread(char *stack_ptr)
688 {
689 #ifdef CONFIG_ARCH_HAS_CUSTOM_SWAP_TO_MAIN
690 arch_switch_to_main_thread(&z_main_thread, stack_ptr, bg_thread_main);
691 #else
692 ARG_UNUSED(stack_ptr);
693 /*
694 * Context switch to main task (entry function is _main()): the
695 * current fake thread is not on a wait queue or ready queue, so it
696 * will never be rescheduled in.
697 */
698 z_swap_unlocked();
699 #endif /* CONFIG_ARCH_HAS_CUSTOM_SWAP_TO_MAIN */
700 CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
701 }
702 #endif /* CONFIG_MULTITHREADING */
703
704 __boot_func
z_early_rand_get(uint8_t * buf,size_t length)705 void __weak z_early_rand_get(uint8_t *buf, size_t length)
706 {
707 static uint64_t state = (uint64_t)CONFIG_TIMER_RANDOM_INITIAL_STATE;
708 int rc;
709
710 #ifdef CONFIG_ENTROPY_HAS_DRIVER
711 const struct device *const entropy = DEVICE_DT_GET_OR_NULL(DT_CHOSEN(zephyr_entropy));
712
713 if ((entropy != NULL) && device_is_ready(entropy)) {
714 /* Try to see if driver provides an ISR-specific API */
715 rc = entropy_get_entropy_isr(entropy, buf, length, ENTROPY_BUSYWAIT);
716 if (rc > 0) {
717 length -= rc;
718 buf += rc;
719 }
720 }
721 #endif /* CONFIG_ENTROPY_HAS_DRIVER */
722
723 while (length > 0) {
724 uint32_t val;
725
726 state = state + k_cycle_get_32();
727 state = state * 2862933555777941757ULL + 3037000493ULL;
728 val = (uint32_t)(state >> 32);
729 rc = MIN(length, sizeof(val));
730 z_early_memcpy((void *)buf, &val, rc);
731
732 length -= rc;
733 buf += rc;
734 }
735 }
736
737 /**
738 *
739 * @brief Initialize kernel
740 *
741 * This routine is invoked when the system is ready to run C code. The
742 * processor must be running in 32-bit mode, and the BSS must have been
743 * cleared/zeroed.
744 *
745 * @return Does not return
746 */
747 __boot_func
748 FUNC_NO_STACK_PROTECTOR
z_cstart(void)749 FUNC_NORETURN void z_cstart(void)
750 {
751 /* gcov hook needed to get the coverage report.*/
752 gcov_static_init();
753
754 /* initialize early init calls */
755 z_sys_init_run_level(INIT_LEVEL_EARLY);
756
757 /* perform any architecture-specific initialization */
758 arch_kernel_init();
759
760 LOG_CORE_INIT();
761
762 #if defined(CONFIG_MULTITHREADING)
763 z_dummy_thread_init(&_thread_dummy);
764 #endif /* CONFIG_MULTITHREADING */
765 /* do any necessary initialization of static devices */
766 z_device_state_init();
767
768 #if CONFIG_SOC_EARLY_INIT_HOOK
769 soc_early_init_hook();
770 #endif
771 #if CONFIG_BOARD_EARLY_INIT_HOOK
772 board_early_init_hook();
773 #endif
774 /* perform basic hardware initialization */
775 z_sys_init_run_level(INIT_LEVEL_PRE_KERNEL_1);
776 #if defined(CONFIG_SMP)
777 arch_smp_init();
778 #endif
779 z_sys_init_run_level(INIT_LEVEL_PRE_KERNEL_2);
780
781 #ifdef CONFIG_REQUIRES_STACK_CANARIES
782 uintptr_t stack_guard;
783
784 z_early_rand_get((uint8_t *)&stack_guard, sizeof(stack_guard));
785 __stack_chk_guard = stack_guard;
786 __stack_chk_guard <<= 8;
787 #endif /* CONFIG_REQUIRES_STACK_CANARIES */
788
789 #ifdef CONFIG_TIMING_FUNCTIONS_NEED_AT_BOOT
790 timing_init();
791 timing_start();
792 #endif /* CONFIG_TIMING_FUNCTIONS_NEED_AT_BOOT */
793
794 #ifdef CONFIG_MULTITHREADING
795 switch_to_main_thread(prepare_multithreading());
796 #else
797 #ifdef ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING
798 /* Custom ARCH-specific routine to switch to main()
799 * in the case of no multi-threading.
800 */
801 ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING(bg_thread_main,
802 NULL, NULL, NULL);
803 #else
804 bg_thread_main(NULL, NULL, NULL);
805
806 /* LCOV_EXCL_START
807 * We've already dumped coverage data at this point.
808 */
809 irq_lock();
810 while (true) {
811 }
812 /* LCOV_EXCL_STOP */
813 #endif /* ARCH_SWITCH_TO_MAIN_NO_MULTITHREADING */
814 #endif /* CONFIG_MULTITHREADING */
815
816 /*
817 * Compiler can't tell that the above routines won't return and issues
818 * a warning unless we explicitly tell it that control never gets this
819 * far.
820 */
821
822 CODE_UNREACHABLE; /* LCOV_EXCL_LINE */
823 }
824
825 #ifdef CONFIG_OBJ_CORE_SYSTEM
init_cpu_obj_core_list(void)826 static int init_cpu_obj_core_list(void)
827 {
828 /* Initialize CPU object type */
829
830 z_obj_type_init(&obj_type_cpu, K_OBJ_TYPE_CPU_ID,
831 offsetof(struct _cpu, obj_core));
832
833 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
834 k_obj_type_stats_init(&obj_type_cpu, &cpu_stats_desc);
835 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
836
837 return 0;
838 }
839
init_kernel_obj_core_list(void)840 static int init_kernel_obj_core_list(void)
841 {
842 /* Initialize kernel object type */
843
844 z_obj_type_init(&obj_type_kernel, K_OBJ_TYPE_KERNEL_ID,
845 offsetof(struct z_kernel, obj_core));
846
847 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
848 k_obj_type_stats_init(&obj_type_kernel, &kernel_stats_desc);
849 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
850
851 k_obj_core_init_and_link(K_OBJ_CORE(&_kernel), &obj_type_kernel);
852 #ifdef CONFIG_OBJ_CORE_STATS_SYSTEM
853 k_obj_core_stats_register(K_OBJ_CORE(&_kernel), _kernel.usage,
854 sizeof(_kernel.usage));
855 #endif /* CONFIG_OBJ_CORE_STATS_SYSTEM */
856
857 return 0;
858 }
859
860 SYS_INIT(init_cpu_obj_core_list, PRE_KERNEL_1,
861 CONFIG_KERNEL_INIT_PRIORITY_OBJECTS);
862
863 SYS_INIT(init_kernel_obj_core_list, PRE_KERNEL_1,
864 CONFIG_KERNEL_INIT_PRIORITY_OBJECTS);
865 #endif /* CONFIG_OBJ_CORE_SYSTEM */
866
