arch/arm/include/kernel_arch_func.h

/*
 * Copyright (c) 2013-2016 Wind River Systems, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file
 * @brief Private kernel definitions (ARM)
 *
 * This file contains private kernel function definitions and various
 * other definitions for the ARM Cortex-M3 processor architecture.
 *
 * This file is also included by assembly language files which must #define
 * _ASMLANGUAGE before including this header file.  Note that kernel
 * assembly source files obtains structure offset values via "absolute symbols"
 * in the offsets.o module.
 */

/* this file is only meant to be included by kernel_structs.h */

#ifndef _kernel_arch_func__h_
#define _kernel_arch_func__h_

#ifdef __cplusplus
extern "C" {
#endif

#ifndef _ASMLANGUAGE
extern void _FaultInit(void);
extern void _CpuIdleInit(void);
static ALWAYS_INLINE void nanoArchInit(void)
{
	_InterruptStackSetup();
	_ExcSetup();
	_FaultInit();
	_CpuIdleInit();
}

static ALWAYS_INLINE void
_arch_switch_to_main_thread(char *main_stack, size_t main_stack_size,
			    _thread_entry_t _main)
{
	/* get high address of the stack, i.e. its start (stack grows down) */
	char *start_of_main_stack;

	start_of_main_stack = main_stack + main_stack_size;
	start_of_main_stack = (void *)STACK_ROUND_DOWN(start_of_main_stack);

	_current = (void *)main_stack;

	__asm__ __volatile__(

		/* move to main() thread stack */
		"msr PSP, %0 \t\n"

		/* unlock interrupts */
#ifdef CONFIG_CPU_CORTEX_M0_M0PLUS
		"cpsie i \t\n"
#else
		"movs %%r1, #0 \n\t"
		"msr BASEPRI, %%r1 \n\t"
#endif

		/* branch to _thread_entry(_main, 0, 0, 0) */
		"mov %%r0, %1 \n\t"
		"bx %2 \t\n"

		/* never gets here */

		:
		: "r"(start_of_main_stack),
		  "r"(_main), "r"(_thread_entry)

		: "r0", "r1", "sp"
	);

	CODE_UNREACHABLE;
}

static ALWAYS_INLINE void
_set_thread_return_value(struct k_thread *thread, unsigned int value)
{
	thread->arch.swap_return_value = value;
}

extern void nano_cpu_atomic_idle(unsigned int);

#define _is_in_isr() _IsInIsr()

extern void _IntLibInit(void);

#endif /* _ASMLANGUAGE */

#ifdef __cplusplus
}
#endif

#endif /* _kernel_arch_func__h_ */