zephyr/arch/arc/core/thread.c

223 lines
6.4 KiB
C

/*
* Copyright (c) 2014 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief New thread creation for ARCv2
*
* Core thread related primitives for the ARCv2 processor architecture.
*/
#include <kernel.h>
#include <toolchain.h>
#include <kernel_structs.h>
#include <offsets_short.h>
#include <wait_q.h>
#ifdef CONFIG_INIT_STACKS
#include <string.h>
#endif /* CONFIG_INIT_STACKS */
#ifdef CONFIG_USERSPACE
#include <arch/arc/v2/mpu/arc_core_mpu.h>
#endif
/* initial stack frame */
struct init_stack_frame {
u32_t pc;
#ifdef CONFIG_ARC_HAS_SECURE
u32_t sec_stat;
#endif
u32_t status32;
u32_t r3;
u32_t r2;
u32_t r1;
u32_t r0;
};
/*
* @brief Initialize a new thread from its stack space
*
* The thread control structure is put at the lower address of the stack. An
* initial context, to be "restored" by __return_from_coop(), is put at
* the other end of the stack, and thus reusable by the stack when not
* needed anymore.
*
* The initial context is a basic stack frame that contains arguments for
* _thread_entry() return address, that points at _thread_entry()
* and status register.
*
* <options> is currently unused.
*
* @param pStackmem the pointer to aligned stack memory
* @param stackSize the stack size in bytes
* @param pEntry thread entry point routine
* @param parameter1 first param to entry point
* @param parameter2 second param to entry point
* @param parameter3 third param to entry point
* @param priority thread priority
* @param options thread options: K_ESSENTIAL
*
* @return N/A
*/
void _new_thread(struct k_thread *thread, k_thread_stack_t *stack,
size_t stackSize, k_thread_entry_t pEntry,
void *parameter1, void *parameter2, void *parameter3,
int priority, unsigned int options)
{
char *pStackMem = K_THREAD_STACK_BUFFER(stack);
_ASSERT_VALID_PRIO(priority, pEntry);
char *stackEnd;
struct init_stack_frame *pInitCtx;
#if CONFIG_USERSPACE
#if CONFIG_ARC_MPU_VER == 2
stackSize = POW2_CEIL(STACK_SIZE_ALIGN(stackSize));
#elif CONFIG_ARC_MPU_VER == 3
stackSize = ROUND_UP(stackSize, STACK_ALIGN);
#endif
#endif
stackEnd = pStackMem + stackSize;
#if CONFIG_USERSPACE
/* for kernel thread, the privilege stack is merged into thread stack */
if (!(options & K_USER)) {
/* if MPU_STACK_GUARD is enabled, reserve the the stack area
* |---------------------| |----------------|
* | user stack | | stack guard |
* |---------------------| to |----------------|
* | stack guard | | kernel thread |
* |---------------------| | stack |
* | privilege stack | | |
* ---------------------------------------------
*/
pStackMem += STACK_GUARD_SIZE;
stackSize = stackSize + CONFIG_PRIVILEGED_STACK_SIZE;
stackEnd += CONFIG_PRIVILEGED_STACK_SIZE + STACK_GUARD_SIZE;
}
#endif
_new_thread_init(thread, pStackMem, stackSize, priority, options);
/* carve the thread entry struct from the "base" of the stack */
pInitCtx = (struct init_stack_frame *)(STACK_ROUND_DOWN(stackEnd) -
sizeof(struct init_stack_frame));
#if CONFIG_USERSPACE
if (options & K_USER) {
pInitCtx->pc = ((u32_t)_user_thread_entry_wrapper);
} else {
pInitCtx->pc = ((u32_t)_thread_entry_wrapper);
}
#else
pInitCtx->pc = ((u32_t)_thread_entry_wrapper);
#endif
#ifdef CONFIG_ARC_HAS_SECURE
pInitCtx->sec_stat = _arc_v2_aux_reg_read(_ARC_V2_SEC_STAT);
#endif
pInitCtx->r0 = (u32_t)pEntry;
pInitCtx->r1 = (u32_t)parameter1;
pInitCtx->r2 = (u32_t)parameter2;
pInitCtx->r3 = (u32_t)parameter3;
/*
* For now set the interrupt priority to 15
* we can leave interrupt enable flag set to 0 as
* seti instruction in the end of the _Swap() will
* enable the interrupts based on intlock_key
* value.
*/
#ifdef CONFIG_ARC_STACK_CHECKING
pInitCtx->status32 = _ARC_V2_STATUS32_SC |
_ARC_V2_STATUS32_E(_ARC_V2_DEF_IRQ_LEVEL);
thread->arch.stack_base = (u32_t) stackEnd;
#else
pInitCtx->status32 = _ARC_V2_STATUS32_E(_ARC_V2_DEF_IRQ_LEVEL);
#endif
#if CONFIG_USERSPACE
/*
* enable US bit, US is read as zero in user mode. This will allow use
* mode sleep instructions, and it enables a form of denial-of-service
* attack by putting the processor in sleep mode, but since interrupt
* level/mask can't be set from user space that's not worse than
* executing a loop without yielding.
*/
pInitCtx->status32 |= _ARC_V2_STATUS32_US;
if (options & K_USER) {
thread->arch.priv_stack_start =
(u32_t) (stackEnd + STACK_GUARD_SIZE);
thread->arch.priv_stack_size =
(u32_t)CONFIG_PRIVILEGED_STACK_SIZE;
} else {
thread->arch.priv_stack_start = 0;
thread->arch.priv_stack_size = 0;
}
#endif
#ifdef CONFIG_THREAD_MONITOR
/*
* In debug mode thread->entry give direct access to the thread entry
* and the corresponding parameters.
*/
thread->entry = (struct __thread_entry *)(pInitCtx);
#endif
/*
* intlock_key is constructed based on ARCv2 ISA Programmer's
* Reference Manual CLRI instruction description:
* dst[31:6] dst[5] dst[4] dst[3:0]
* 26'd0 1 STATUS32.IE STATUS32.E[3:0]
*/
thread->arch.intlock_key = 0x3F;
thread->arch.relinquish_cause = _CAUSE_COOP;
thread->callee_saved.sp =
(u32_t)pInitCtx - ___callee_saved_stack_t_SIZEOF;
/* initial values in all other regs/k_thread entries are irrelevant */
thread_monitor_init(thread);
}
#ifdef CONFIG_USERSPACE
FUNC_NORETURN void _arch_user_mode_enter(k_thread_entry_t user_entry,
void *p1, void *p2, void *p3)
{
_current->base.user_options |= K_USER;
/*
* ajust the thread stack layout
* |----------------| |---------------------|
* | stack guard | | user stack |
* |----------------| to |---------------------|
* | kernel thread | | stack guard |
* | stack | |---------------------|
* | | | privilege stack |
* ---------------------------------------------
*/
_current->stack_info.start = (u32_t)_current->stack_obj;
_current->stack_info.size -= CONFIG_PRIVILEGED_STACK_SIZE;
_current->arch.priv_stack_start =
(u32_t) (_current->stack_info.start +
_current->stack_info.size + STACK_GUARD_SIZE);
_current->arch.priv_stack_size =
(u32_t)CONFIG_PRIVILEGED_STACK_SIZE;
/* possible optimizaiton: no need to load mem domain anymore */
/* need to lock cpu here ? */
configure_mpu_thread(_current);
_arc_userspace_enter(user_entry, p1, p2, p3,
(u32_t)_current->stack_obj,
_current->stack_info.size);
CODE_UNREACHABLE;
}
#endif