static void prvSVCHandler( unsigned long *pulParam )
{
unsigned char ucSVCNumber;
/* The stack contains: r0, r1, r2, r3, r12, r14, the return address and
xPSR. The first argument (r0) is pulParam[ 0 ]. */
ucSVCNumber = ( ( unsigned char * ) pulParam[ portOFFSET_TO_PC ] )[ -2 ];
switch( ucSVCNumber )
{
case portSVC_START_SCHEDULER : *(portNVIC_SYSPRI1) |= portNVIC_SVC_PRI;
prvRestoreContextOfFirstTask();
break;
case portSVC_YIELD : *(portNVIC_INT_CTRL) = portNVIC_PENDSVSET;
break;
case portSVC_RAISE_PRIVILEGE : __asm volatile
(
" mrs r1, control \n" /* Obtain current control value. */
" bic r1, #1 \n" /* Set privilege bit. */
" msr control, r1 \n" /* Write back new control value. */
:::"r1"
);
break;
default : /* Unknown SVC call. */
break;
}
}
static void prvSVCHandler(uint32_t *pulParam )
{
uint8_t ucSVCNumber;
/* The stack contains: r0, r1, r2, r3, r12, r14, the return address and
xPSR. The first argument (r0) is pulParam[ 0 ]. */
ucSVCNumber = ( ( uint8_t * ) pulParam[ portOFFSET_TO_PC ] )[ -2 ];
switch( ucSVCNumber )
{
case portSVC_START_SCHEDULER : *(portNVIC_SYSPRI1) |= portNVIC_SVC_PRI;
prvRestoreContextOfFirstTask();
break;
case portSVC_YIELD : *(portNVIC_INT_CTRL) = portNVIC_PENDSVSET;
/* Barriers are normally not required
but do ensure the code is completely
within the specified behaviour for the
architecture. */
__asm volatile( "dsb" );
__asm volatile( "isb" );
break;
case portSVC_SYSCALL : {
/* Read the syscall index from the instruction that raised this syscall. */
uint16_t syscall_index = ((uint16_t*)pulParam[portOFFSET_TO_PC])[0];
pulParam[portOFFSET_TO_PC] = vApplicationStartSyscall(syscall_index);
/* Modify the control register to raise the thread mode privilege level */
__asm volatile
(
" mrs r1, control \n" /* Obtain current control value. */
" bic r1, #1 \n" /* Set privilege bit. */
" msr control, r1 \n" /* Write back new control value. */
:::"r1"
);
/* Now we're going to return from this ISR. If everything goes right, we'll land in
the address returned from vApplicationStartSyscall in privileged mode. */
}
break;
default : /* Unknown SVC call. */
break;
}
}
static void prvSVCHandler( uint32_t *pulParam )
{
uint8_t ucSVCNumber;
/* The stack contains: r0, r1, r2, r3, r12, r14, the return address and
xPSR. The first argument (r0) is pulParam[ 0 ]. */
ucSVCNumber = ( ( uint8_t * ) pulParam[ portOFFSET_TO_PC ] )[ -2 ];
switch( ucSVCNumber )
{
case portSVC_START_SCHEDULER :
*(portNVIC_SYSPRI1) |= portNVIC_SVC_PRI;
prvRestoreContextOfFirstTask();
break;
case portSVC_YIELD :
*(portNVIC_INT_CTRL) = portNVIC_PENDSVSET;
/* Barriers are normally not required
but do ensure the code is completely
within the specified behaviour for the
architecture. */
__asm volatile( "dsb" );
__asm volatile( "isb" );
break;
case portSVC_RAISE_PRIVILEGE :
__asm volatile
(
" mrs r1, control \n" /* Obtain current control value. */
" bic r1, #1 \n" /* Set privilege bit. */
" msr control, r1 \n" /* Write back new control value. */
:::"r1"
);
break;
default : /* Unknown SVC call. */
break;
}
}
