linux上使用arm汇编的几个小函数

void CPUSwitchToPrivilegedMode(void)
{
    asm("    SWI   #458752");
}

void CPUReadCPSR(void)
{
    unsigned int i = 777;
    asm("    mrs     %0, CPSR\n\t"
        :"=r"(i));
    printk(KERN_INFO "CPSR = %#x\n", i);
}