void kos_init_regs(void)
{
uint32_t msp = __get_MSP();
__set_PSP(msp);
__set_MSP((uint32_t)g_kos_isr_stk + g_kos_isr_stksz);
__set_CONTROL(2);
}
/*******************************************************************************
* 名 称： IAP_JumpTo()
* 功 能： 跳转到应用程序段
* 入口参数：
* 出口参数： 无
* 作 者： 无名沈
* 创建日期： 2014-04-23
* 修 改：
* 修改日期：
*******************************************************************************/
void IAP_JumpTo(u32 appAddr)
{
u32 JumpAddress = 0;
u8 cpu_sr;
/***********************************************
* 描述： 保存程序地址
*/
IAP_SetAppAddr(appAddr);
/***********************************************
* 描述： 关中断，防止值被中断修改
*/
CPU_CRITICAL_ENTER();
/***********************************************
* 描述： 外设恢复默认，避免进入应用程序后影响程序正常运行
*/
IAP_DevDeInit();
/***********************************************
* 描述： 获取应用入口及初始化堆栈指针
*/
JumpAddress =*(volatile u32*) (appAddr + 4); // 地址+4为PC地址
pApp = (pFunction)JumpAddress; // 函数指针指向APP
__set_MSP (*(volatile u32*) appAddr); // 初始化主堆栈指针（MSP）
__set_PSP (*(volatile u32*) appAddr); // 初始化进程堆栈指针（PSP）
__set_CONTROL (0); // 清零CONTROL
/***********************************************
* 描述： 跳转到APP程序
*/
pApp();
CPU_CRITICAL_EXIT();
}
static void tt_use_PSP(unsigned int irq_stack_addr)
{
__set_PSP(__get_MSP());
__set_MSP(irq_stack_addr);
__set_CONTROL(2);
__ISB();
}
static void isr_reset(void)
{
// remove compiler warning
(void)g_pfnVectors;
/**
* The hyperload bootloader sets the MSP/PSP upon a true reset, which is when the
* LPC17xx (Cortex-M3) sets the values of the stack pointer. But since we are
* booting after a bootloader, we have to manually setup the stack pointers ourselves.
*/
do {
const uint32_t topOfStack = (uint32_t) &_vStackTop;
__set_PSP(topOfStack);
__set_MSP(topOfStack);
} while(0);
do {
// Copy data from FLASH to RAM
unsigned int LoadAddr, ExeAddr, SectionLen;
unsigned int *SectionTableAddr;
// Load base address of Global Section Table
SectionTableAddr = &__data_section_table;
// Copy the data sections from flash to SRAM.
while (SectionTableAddr < &__data_section_table_end)
{
LoadAddr = *SectionTableAddr++;
ExeAddr = *SectionTableAddr++;
SectionLen = *SectionTableAddr++;
data_init(LoadAddr, ExeAddr, SectionLen);
}
// At this point, SectionTableAddr = &__bss_section_table;
// Zero fill the bss segment
while (SectionTableAddr < &__bss_section_table_end)
{
ExeAddr = *SectionTableAddr++;
SectionLen = *SectionTableAddr++;
bss_init(ExeAddr, SectionLen);
}
} while (0) ;
#if defined (__cplusplus)
__libc_init_array(); // Call C++ library initialization
#endif
do {
low_level_init(); // Initialize minimal system, such as Clock & UART
high_level_init(); // Initialize high level board specific features
main(); // Finally call main()
} while(0);
// In case main() exits:
uart0_init(SYS_CFG_UART0_BPS);
u0_dbg_put("main() should never exit on this system\n");
while (1) {
;
}
}
void Init_Cpu(void)
{
__set_PSP((uint32_t)msp_top);
__set_PRIMASK(1);
__set_FAULTMASK(1);
__set_CONTROL(0);
#if (CN_CPU_OPTIONAL_FPU == 1)
startup_scb_reg->CPACR = (3UL << 20)|(3UL << 22); //使能FPU
startup_scb_reg->FPCCR = (1UL << 31); //关闭lazy stacking
#endif
switch(startup_scb_reg->CPUID)
{
}
extern void SysClockInit(void);
SysClockInit();
#ifdef USE_HAL_DRIVER
HAL_TickInit();
#endif
extern void SRAM_Init(void);
SRAM_Init();
IAP_SelectLoadProgam();
}
void execute_user_code(void)
{
void (*user_code_entry)(void);
unsigned *p; // used for loading address of reset handler from user flash
/* Change the Vector Table to the USER_FLASH_START
in case the user application uses interrupts */
SCB->VTOR = (USER_FLASH_START & 0x1FFFFF80);
/* SP (stack pointer) register must be set correctly before jump to the
* user application: http://www.keil.com/forum/17342/
*/
__set_PSP(USER_FLASH_START);
// Load contents of second word of user flash - the reset handler address
// in the applications vector table
p = (unsigned *)(USER_FLASH_START +4);
// Set user_code_entry to be the address contained in that second word
// of user flash
user_code_entry = (void *) *p;
// Jump to user application
user_code_entry();
}
//! @brief Exits bootloader and jumps to the user application.
static void jump_to_application(uint32_t applicationAddress, uint32_t stackPointer)
{
#if BL_FEATURE_OTFAD_MODULE
quadspi_cache_clear();
oftfad_resume_as_needed();
#endif
shutdown_cleanup(kShutdownType_Shutdown);
// Create the function call to the user application.
// Static variables are needed since changed the stack pointer out from under the compiler
// we need to ensure the values we are using are not stored on the previous stack
static uint32_t s_stackPointer = 0;
s_stackPointer = stackPointer;
static void (*farewellBootloader)(void) = 0;
farewellBootloader = (void (*)(void))applicationAddress;
// Set the VTOR to the application vector table address.
SCB->VTOR = (uint32_t)APP_VECTOR_TABLE;
// Set stack pointers to the application stack pointer.
__set_MSP(s_stackPointer);
__set_PSP(s_stackPointer);
// while (1); /* SGF REMOVE */
// Jump to the application.
farewellBootloader();
// Dummy fcuntion call, should never go to this fcuntion call
shutdown_cleanup(kShutdownType_Shutdown);
}
void Init_Cpu(void)
{
__set_PSP((uint32_t)msp_top);
__set_PRIMASK(1);
__set_FAULTMASK(1);
__set_CONTROL(0);
#if (CN_CPU_OPTIONAL_FPU == 1)
pg_scb_reg->CPACR = (3UL << 20)|(3UL << 22); //使能FPU
pg_scb_reg->FPCCR = (1UL << 31); //关闭lazy stacking
#endif
switch(pg_scb_reg->CPUID)
{
// case cn_revision_r0p1://todo
// break; //好像没什么要做的
}
extern void WDT_Disable(void);
WDT_Disable(); //关狗
extern void SysClockInit(void);
SysClockInit();
extern void SDRAM_Init(void);
SDRAM_Init();
extern void Cache_Init(void);
Cache_Init();
Load_Preload();
}
int init_sys(void)
{
SCB->CCR |= SCB_CCR_STKALIGN_Msk; // enable double word stack alignment
PSP_array[0] = ((unsigned int)task0_stack) + (sizeof task0_stack) - 16*4; // top of stack
HW32_REG((PSP_array[0] + (14<<2))) = (unsigned long)task0; // initial Program Counter
HW32_REG((PSP_array[0] + (15<<2))) = 0x01000000; // initial PSR
PSP_array[1] = ((unsigned int)task1_stack) + (sizeof task1_stack) - 16*4;
HW32_REG((PSP_array[1] + (14<<2))) = (unsigned long)task1;
HW32_REG((PSP_array[1] + (15<<2))) = 0x01000000;
curr_task = 0;
__set_PSP((PSP_array[curr_task] + 16*4)); // set PSP to top of stack
NVIC_SetPriority(PendSV_IRQn, 0xFF);
SysTick_Config(168000);
__set_CONTROL(0x3);
__ISB();
task0();
/*while(1) {
stop_cpu;
}; */
}
void _start()
{
/* copy data segment from flash to ram */
{
const size_t datalen = (size_t) &_edata - (unsigned int) &_sdata;
memcpy(&_sdata, &_sidata, datalen);
}
/* zero out bss segment */
{
const size_t bsslen = (size_t) &_ebss - (unsigned int) &_sbss;
memset(&_sbss, 0x0, bsslen);
}
SystemInit();
/* set process stack */
__set_PSP((uint32_t) &_eusrstack);
/* enable drivers */
for (size_t i = 0; i < sizeof(drivers); i++)
{
const driver_t* drv_p = drivers[i];
if (drv_p->driver_reset != NULL)
drv_p->driver_reset();
enable_clocks(drv_p);
}
(void) _init_crt1();
(void) main();
}
/**
\brief Test case: TC_CoreFunc_PSP
\details
- Check if __get_PSP and __set_PSP intrinsic can be used to manipulate process stack pointer.
*/
void TC_CoreFunc_PSP (void) {
// don't use stack for this variables
static uint32_t orig;
static uint32_t psp;
static uint32_t result;
orig = __get_PSP();
psp = orig + 0x12345678U;
__set_PSP(psp);
result = __get_PSP();
__set_PSP(orig);
ASSERT_TRUE(result == psp);
}
static inline void set_and_switch_to_psp(void)
{
u32_t process_sp;
process_sp = (u32_t)&_interrupt_stack + CONFIG_ISR_STACK_SIZE;
__set_PSP(process_sp);
switch_sp_to_psp();
}
/** Switch the context back from the destination box to the source one.
*
* @internal
*
* In this function we keep the same naming convention of the switch-in. Hence,
* here the destination box is the one we are leaving, the source box is the one
* we are switching to. We do not need any input from the caller as we already
* know where we are switching to from the stacked state.
*
* @warning With thread context switches there is no context switch-out, but
* only a context switch-in (from the current thread to the next one), so this
* function should not be used for that purpose. An error will be thrown if used
* for thread switches. */
TContextPreviousState * context_switch_out(TContextSwitchType context_type)
{
uint8_t src_id, dst_id;
uint32_t src_sp;
TContextPreviousState * previous_state;
/* This function is not needed for unbound context switches.
* In those cases there is only a switch from a source box to a destination
* box, and it can be done without state keeping. It is the host OS that
* takes care of switching the stacks. */
if (context_type == CONTEXT_SWITCH_UNBOUND_THREAD) {
HALT_ERROR(NOT_ALLOWED, "Unbound context switching (e.g. for thread context switching) does not need to switch "
"out. Just call the context_switch_in(...) function repeatedly to switch from one task "
"to another.");
}
/* Destination box: Gather information from the current state. */
dst_id = g_active_box;
/* Source box: Gather information from the previous state. */
/* This function halts if it finds an error. */
previous_state = context_state_pop();
src_id = previous_state->src_id;
src_sp = previous_state->src_sp;
/* The source/destination box IDs can be the same (for example, in IRQs). */
if (src_id != dst_id) {
/* Store outgoing newlib reent pointer. */
UvisorBoxIndex * index = (UvisorBoxIndex *) g_context_current_states[dst_id].bss;
index->bss.address_of.newlib_reent = (uint32_t) *(__uvisor_config.newlib_impure_ptr);
/* Update the ID of the currently active box. */
g_active_box = src_id;
/* Update the context pointer to the one of the source box. */
index = (UvisorBoxIndex *) g_context_current_states[src_id].bss;
*(__uvisor_config.uvisor_box_context) = (uint32_t *) index;
/* Switch MPU configurations. */
/* This function halts if it finds an error. */
vmpu_switch(dst_id, src_id);
/* Restore incoming newlib reent pointer. */
*(__uvisor_config.newlib_impure_ptr) = (uint32_t *) index->bss.address_of.newlib_reent;
}
/* Set the stack pointer for the source box. This is only needed if the
* context switch is tied to a function.
* Unbound context switches require the host OS to set the correct stack
* pointer before handling execution to the unprivileged code. */
if (context_type == CONTEXT_SWITCH_FUNCTION_GATEWAY ||
context_type == CONTEXT_SWITCH_FUNCTION_ISR ||
context_type == CONTEXT_SWITCH_FUNCTION_DEBUG) {
__set_PSP(src_sp);
}
return previous_state;
}
/*!
\brief C part of the SVC exception handler
SVC 0 is initializing the OS and starting the scheduler.
Each thread stack frame is initialized.
\param svc_args Used to extract the SVC number
*/
void SVC_Handler_C(unsigned int * svc_args)
{
uint8_t svc_number;
svc_number = ((char *) svc_args[6])[-2]; // Memory[(Stacked PC)-2]
// marking kernel as busy
kernel_busy = 1;
switch(svc_number) {
//************* SVC( 0 ) OS Start
case (0): // OS start
// Starting the task scheduler
//TWP playing a trick here!? by making curr = next, will make next's stack and current's stack the same stack!
// will save (garbage) current register values, and then immediately restore them as next's initial values :-)
curr_task = rtr_q_h; // Switch to head ready-to-run task (Current task)
// when current task was put in RTRQ its state was set to RUNNING
svc_exc_return = HW32_REG(( curr_task->stack_p )); // Return to thread with PSP
__set_PSP(( (uint32_t) curr_task->stack_p + 10*4)); // Set PSP to @R0 of task 0 exception stack frame
NVIC_SetPriority(PendSV_IRQn, 0xFF); // Set PendSV to lowest possible priority
if (SysTick_Config(os_sysTickTicks) != 0) // 1000 Hz SysTick interrupt on 16MHz core clock
{
stop_cpu2;
// Impossible SysTick_Config number of ticks
}
__set_CONTROL(0x3); // Switch to use Process Stack, unprivileged state
__ISB(); // Execute ISB after changing CONTROL (architectural recommendation)
break;
//************* SVC( 1 ) Thread Yield
case (1): // Thread Yield
if (curr_task != rtr_q_h)
{
// Context switching needed
ScheduleContextSwitch();
}
__ISB();
break;
//************* SVC( 2 ) Stack Frame Allocation for First Launch
//TWPV6: no longer used! Functionality moved to osThreadCreate ... case left here (for now)
case (2): // Stack Allocation
__ISB();
break;
default:
#if ((ENABLE_KERNEL_PRINTF) && (ENABLE_KERNEL_PRINTF == 1))
printf("ERROR: Unknown SVC service number\n\r");
printf("- SVC number 0x%x\n\r", svc_number);
#endif
stop_cpu2;
break;
} // end switch
// marking kernel as normal
kernel_busy = 0;
}
/**
* @brief Exception exit redirection to _port_switch_from_isr().
*/
void _port_irq_epilogue(void) {
port_lock_from_isr();
if ((SCB->ICSR & SCB_ICSR_RETTOBASE_Msk) != 0) {
/* The port_extctx structure is pointed by the PSP register.*/
struct port_extctx *ctxp = (struct port_extctx *)__get_PSP();
/* Adding an artificial exception return context, there is no need to
populate it fully.*/
ctxp--;
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
/* Setting up a fake XPSR register value.*/
ctxp->xpsr = (regarm_t)0x01000000;
/* The exit sequence is different depending on if a preemption is
required or not.*/
if (chSchIsRescRequiredI()) {
/* Preemption is required we need to enforce a context switch.*/
ctxp->pc = (regarm_t)_port_switch_from_isr;
#if CORTEX_USE_FPU
/* Enforcing a lazy FPU state save by accessing the FPCSR register.*/
(void) __get_FPSCR();
#endif
}
else {
/* Preemption not required, we just need to exit the exception
atomically.*/
ctxp->pc = (regarm_t)_port_exit_from_isr;
}
#if CORTEX_USE_FPU
{
uint32_t fpccr;
/* Saving the special register SCB_FPCCR into the reserved offset of
the Cortex-M4 exception frame.*/
(ctxp + 1)->fpccr = (regarm_t)(fpccr = FPU->FPCCR);
/* Now the FPCCR is modified in order to not restore the FPU status
from the artificial return context.*/
FPU->FPCCR = fpccr | FPU_FPCCR_LSPACT_Msk;
}
#endif
/* Note, returning without unlocking is intentional, this is done in
order to keep the rest of the context switch atomic.*/
return;
}
port_unlock_from_isr();
}
/**
* @brief PendSV vector.
* @details The PendSV vector is used for exception mode re-entering after a
* context switch.
*/
void PendSV_Handler(void) {
/* The port_extctx structure is pointed by the PSP register.*/
struct port_extctx *ctxp = (struct port_extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
}
void Init_Cpu(void)
{
__set_PSP((uint32_t)msp_top);
__set_PRIMASK(1);
__set_FAULTMASK(1);
__set_CONTROL(0);
switch(pg_scb_reg->CPUID)
{
case cn_revision_r0p0:
break; //市场没有版本0的芯片
case cn_revision_r1p0:
pg_scb_reg->CCR |= 1<<bo_scb_ccr_stkalign;
break;
case cn_revision_r1p1:
pg_scb_reg->CCR |= 1<<bo_scb_ccr_stkalign;
break;
case cn_revision_r2p0:break; //好像没什么要做的
}
pg_inflash_fpec_reg->ACR &= ~(u32)0x1f;
pg_inflash_fpec_reg->ACR |= (CN_CFG_MCLK-1)/24000000; //设置等待周期。
pg_inflash_fpec_reg->ACR |= 0x10; //开启预取
if(((pg_rcc_reg->CR & cn_cr_check_mask) != cn_cr_check)
|| ((pg_rcc_reg->CFGR & cn_cfgr_check_mask) != cn_cfgr_check))
{
//开始初始化时钟
//step1:复位时钟控制寄存器
pg_rcc_reg->CR |= (uint32_t)0x00000001;
// 复位 SW[1:0], HPRE[3:0], PPRE1[2:0], PPRE2[2:0], ADCPRE[1:0] MCO[2:0] 位
pg_rcc_reg->CFGR &= (uint32_t)0xF8FF0000;
// 复位 HSEON, CSSON and PLLON 位
pg_rcc_reg->CR &= (uint32_t)0xFEF6FFFF;
// 复位 HSEBYP 位
pg_rcc_reg->CR &= (uint32_t)0xFFFBFFFF;
// 复位 PLLSRC, PLLXTPRE, PLLMUL[3:0] and USBPRE 位
pg_rcc_reg->CFGR &= (uint32_t)0xFF80FFFF;
// 禁止所有中断
pg_rcc_reg->CIR = 0x00000000;
//step2:设置各时钟控制位以及倍频、分频值
pg_rcc_reg->CFGR = cn_cfgr_set+(7<<24); // set clock configuration register
pg_rcc_reg->CR = cn_cr_set; // set clock control register
while(bb_rcc_cr_hserdy ==0);
while(bb_rcc_cr_pllrdy ==0);
}
SRAM_Init();
Load_Preload();
}
/**
* @brief Exception exit redirection to _port_switch_from_isr().
*/
void _port_irq_epilogue(void) {
port_lock_from_isr();
if ((SCB_ICSR & ICSR_RETTOBASE) != 0) {
struct extctx *ctxp;
/* Current PSP value.*/
ctxp = (struct extctx *)__get_PSP();
/* Adding an artificial exception return context, there is no need to
populate it fully.*/
ctxp--;
__set_PSP((unsigned long)ctxp);
ctxp->xpsr = (regarm_t)0x01000000;
/* The exit sequence is different depending on if a preemption is
required or not.*/
if (chSchIsPreemptionRequired()) {
/* Preemption is required we need to enforce a context switch.*/
ctxp->pc = (regarm_t)_port_switch_from_isr;
#if CORTEX_USE_FPU
/* Triggering a lazy FPU state save.*/
(void)__get_FPSCR();
#endif
}
else {
/* Preemption not required, we just need to exit the exception
atomically.*/
ctxp->pc = (regarm_t)_port_exit_from_isr;
}
#if CORTEX_USE_FPU
{
uint32_t fpccr;
/* Saving the special register SCB_FPCCR into the reserved offset of
the Cortex-M4 exception frame.*/
(ctxp + 1)->fpccr = (regarm_t)(fpccr = SCB_FPCCR);
/* Now the FPCCR is modified in order to not restore the FPU status
from the artificial return context.*/
SCB_FPCCR = fpccr | FPCCR_LSPACT;
}
#endif
/* Note, returning without unlocking is intentional, this is done in
order to keep the rest of the context switch atomic.*/
return;
}
port_unlock_from_isr();
}
void cmd_reset(void)
{
rt_uint32_t usrAddr = 0x08000000;
typedef void (*funcPtr)(void);
typedef volatile uint32_t vu32;
__set_PRIMASK(0); //关闭所有中断，可以没有
if(((*(vu32*)usrAddr)&0x2FFE0000)==0x20000000) //判断地址是不是在RAM之内
{
rt_uint32_t jumpAddr = *(vu32*) (usrAddr+0x04); /* reset ptr in vector table */
funcPtr usrMain1 = (funcPtr)jumpAddr;
__set_PSP(*(vu32*)usrAddr); //设置堆栈指针
usrMain1(); /* go! */
}
}
/**
* @brief NMI vector.
* @details The NMI vector is used for exception mode re-entering after a
* context switch.
*/
void NMI_Handler(void) {
/* The port_extctx structure is pointed by the PSP register.*/
struct port_extctx *ctxp = (struct port_extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
/* Restoring the normal interrupts status.*/
port_unlock_from_isr();
}
/**
* @brief PendSV vector.
* @details The PendSV vector is used for exception mode re-entering after a
* context switch.
* @note The PendSV vector is only used in compact kernel mode.
*/
void PendSVVector(void) {
struct extctx *ctxp;
/* Current PSP value.*/
ctxp = (struct extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
#if CORTEX_USE_FPU
/* Restoring the special register SCB_FPCCR.*/
SCB_FPCCR = (uint32_t)ctxp->fpccr;
SCB_FPCAR = SCB_FPCAR + sizeof (struct extctx);
#endif
__set_PSP((unsigned long)ctxp);
}
/**
* @brief Exception exit redirection to _port_switch_from_isr().
*/
void _port_irq_epilogue(void) {
port_lock_from_isr();
if ((SCB->ICSR & SCB_ICSR_RETTOBASE_Msk) != 0) {
struct port_extctx *ctxp;
#if CORTEX_USE_FPU
/* Enforcing a lazy FPU state save by accessing the FPCSR register.*/
(void) __get_FPSCR();
#endif
/* The port_extctx structure is pointed by the PSP register.*/
ctxp = (struct port_extctx *)__get_PSP();
/* Adding an artificial exception return context, there is no need to
populate it fully.*/
ctxp--;
/* Setting up a fake XPSR register value.*/
ctxp->xpsr = (regarm_t)0x01000000;
#if CORTEX_USE_FPU
ctxp->fpscr = (regarm_t)FPU->FPDSCR;
#endif
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
/* The exit sequence is different depending on if a preemption is
required or not.*/
if (chSchIsPreemptionRequired()) {
/* Preemption is required we need to enforce a context switch.*/
ctxp->pc = (regarm_t)_port_switch_from_isr;
}
else {
/* Preemption not required, we just need to exit the exception
atomically.*/
ctxp->pc = (regarm_t)_port_exit_from_isr;
}
/* Note, returning without unlocking is intentional, this is done in
order to keep the rest of the context switch atomic.*/
return;
}
port_unlock_from_isr();
}
void Reset_Handler( void )
{
#if main_stack_size + proc_stack_size > 0
/* Initialize the process stack pointer */
__set_PSP((unsigned)__initial_sp);
__set_CONTROL(CONTROL_SPSEL_Msk);
#endif
#if __FPU_USED
/* Set CP10 and CP11 Full Access */
SCB->CPACR = 0x00F00000U;
#endif
#ifndef __NO_SYSTEM_INIT
/* Call the system clock intitialization function */
SystemInit();
#endif
/* Call the application's entry point */
__main();
}
/**
* @brief PendSV vector.
* @details The PendSV vector is used for exception mode re-entering after a
* context switch.
* @note The PendSV vector is only used in compact kernel mode.
*/
void PendSV_Handler(void) {
struct port_extctx *ctxp;
#if CORTEX_USE_FPU
/* Enforcing unstacking of the FP part of the context.*/
FPU->FPCCR &= ~FPU_FPCCR_LSPACT_Msk;
#endif
/* The port_extctx structure is pointed by the PSP register.*/
ctxp = (struct port_extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
}
/**
* @brief PendSV vector.
* @details The PendSV vector is used for exception mode re-entering after a
* context switch.
* @note The PendSV vector is only used in compact kernel mode.
*/
void PendSVVector(void) {
struct extctx *ctxp;
#if CORTEX_USE_FPU
/* Enforcing unstacking of the FP part of the context.*/
SCB_FPCCR &= ~FPCCR_LSPACT;
#endif
/* Current PSP value.*/
ctxp = (struct extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
/* Restoring real position of the original stack frame.*/
__set_PSP((unsigned long)ctxp);
}
/**
* @brief PendSV vector.
* @details The PendSV vector is used for exception mode re-entering after a
* context switch.
* @note The PendSV vector is only used in compact kernel mode.
*/
void PendSV_Handler(void) {
/* The port_extctx structure is pointed by the PSP register.*/
struct port_extctx *ctxp = (struct port_extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
#if CORTEX_USE_FPU
/* Restoring the special register FPCCR.*/
FPU->FPCCR = (uint32_t)ctxp->fpccr;
FPU->FPCAR = FPU->FPCAR + sizeof (struct port_extctx);
#endif
/* Writing back the modified PSP value.*/
__set_PSP((uint32_t)ctxp);
}
void nOS_InitSpecific(void)
{
#if (NOS_CONFIG_DEBUG > 0)
size_t i;
for (i = 0; i < NOS_CONFIG_ISR_STACK_SIZE; i++) {
_isrStack[i] = 0xFFFFFFFFUL;
}
#endif
/* Copy MSP to PSP */
__set_PSP(__get_MSP());
/* Set MSP to local ISR stack */
__set_MSP((uint32_t)&_isrStack[NOS_CONFIG_ISR_STACK_SIZE] & 0xFFFFFFF8UL);
/* Set current stack to PSP and privileged mode */
__set_CONTROL(__get_CONTROL() | 0x00000002UL);
/* Set PendSV exception to lowest priority */
*(volatile uint32_t *)0xE000ED20UL |= 0x00FF0000UL;
}
/**
* @brief Exception exit redirection to _port_switch_from_isr().
*/
void _port_irq_epilogue(void) {
port_lock_from_isr();
if ((SCB_ICSR & ICSR_RETTOBASE) != 0) {
struct extctx *ctxp;
#if CORTEX_USE_FPU
/* Enforcing a lazy FPU state save. Note, it goes in the original
context because the FPCAR register has not been modified.*/
(void)__get_FPSCR();
#endif
/* Current PSP value.*/
ctxp = (struct extctx *)__get_PSP();
/* Adding an artificial exception return context, there is no need to
populate it fully.*/
ctxp--;
ctxp->xpsr = (regarm_t)0x01000000;
#if CORTEX_USE_FPU
ctxp->fpscr = (regarm_t)SCB_FPDSCR;
#endif
__set_PSP((unsigned long)ctxp);
/* The exit sequence is different depending on if a preemption is
required or not.*/
if (chSchIsPreemptionRequired()) {
/* Preemption is required we need to enforce a context switch.*/
ctxp->pc = (regarm_t)_port_switch_from_isr;
}
else {
/* Preemption not required, we just need to exit the exception
atomically.*/
ctxp->pc = (regarm_t)_port_exit_from_isr;
}
/* Note, returning without unlocking is intentional, this is done in
order to keep the rest of the context switch atomic.*/
return;
}
port_unlock_from_isr();
}
/**
* Boots the image described by the supplied image header.
*
* @param hdr The header for the image to boot.
*/
void
hal_system_start(void *img_start)
{
typedef void jump_fn(void);
uint32_t base0entry;
uint32_t jump_addr;
jump_fn *fn;
/* First word contains initial MSP value. */
__set_MSP(*(uint32_t *)img_start);
__set_PSP(*(uint32_t *)img_start);
/* Second word contains address of entry point (Reset_Handler). */
base0entry = *(uint32_t *)(img_start + 4);
jump_addr = base0entry;
fn = (jump_fn *)jump_addr;
/* Jump to image. */
fn();
}
/**
* @brief SVC vector.
* @details The SVC vector is used for exception mode re-entering after a
* context switch.
* @note The PendSV vector is only used in advanced kernel mode.
*/
void SVC_Handler(void) {
struct port_extctx *ctxp;
#if CORTEX_USE_FPU
/* Enforcing unstacking of the FP part of the context.*/
FPU->FPCCR &= ~FPU_FPCCR_LSPACT_Msk;
#endif
/* The port_extctx structure is pointed by the PSP register.*/
ctxp = (struct port_extctx *)__get_PSP();
/* Discarding the current exception context and positioning the stack to
point to the real one.*/
ctxp++;
/* Restoring real position of the original stack frame.*/
__set_PSP((uint32_t)ctxp);
/* Restoring the normal interrupts status.*/
port_unlock_from_isr();
}
