How to realize atomic&spin_lock operation in s32R MCU's

[15370749]

I user S32R274, it's a muti core MCUs and has hardware lock between cpus.

but , i think a mechanism  like spin_lock/spin_lock_irqsave  and atomic is needed in 

muti-core MCU. 

so I test like 

static __inline__ int atomic_add_return(int a, atomic_t *v)
{
int t;

__asm__ __volatile__(
"1: lwarx %0,0,%2 # atomic_add_return\n\
add %0,%1,%0\n"
" stwcx. %0,0,%2 \n\
se_bne 1b"
SMP_ISYNC
: "=&r" (t)
: "r" (a), "r" (&v->counter)
: "cc", "memory");

return t;
}

but it seems not a atomic operation in a concurrent scenario。

So,do anyone know how to do it and pls tell me .

thanks a lot

[lukaszadrapa]

Hi,

notice that reservation logic is not implemented between the cores. It can be used only on single core for multitasking.

Between the cores, it's necessary to use semaphores:

https://www.nxp.com/docs/en/application-note/AN4805.pdf

Regards,

Lukas